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Hypersomnia encompasses a group of disorders characterized by excessive daytime sleepiness that can significantly impair quality of life and neurologic function. In this episode, Dr. Margaret Kay-Stacey discusses how to recognize and evaluate hypersomnia, reviews key features of narcolepsy and idiopathic hypersomnia, and highlights the many neurologic conditions associated with excessive sleepiness. Learn practical approaches to diagnosis, treatment, and distinguishing primary hypersomnia disorders from more common causes such as insufficient sleep, sleep apnea, medications, and depression.
In this episode, Gordon Smith, MD, FAAN, speaks with Margaret Kay-Stacey, MD, author of the article "Hypersomnia" in the Continuum® August 2026 Sleep Neurology issue.
Dr. Smith is a Continuum® Audio interviewer and a professor and chair of neurology at Kenneth and Dianne Wright Distinguished Chair in Clinical and Translational Research at Virginia Commonwealth University in Richmond, Virginia.  
Dr. Kay-Stacey is an Assistant Professor of Neurology and Ambulatory Medical Director at the University of Chicago Medical Center in Chicago, Illinois.
Additional Resources
Read the article: Hypersomnia
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Host: @GordonSmithMD
 Full episode transcript available here
Dr Smith: So, what do myotonic dystrophy, Parkinson's disease, and traumatic brain injury have in common? It turns out that each can cause clinically significant and meaningful hypersomnolence. And did you know that narcolepsy has the same population prevalence in the United States as myasthenia gravis, something I commonly see in clinic? If you want to learn more about hypersomnolence and how it impacts the patients you care for and what to do about it, keep listening. 
Dr Jones: This is Dr. Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. 
Dr Smith: This is Dr. Gordon Smith. Today, I'm interviewing Dr. Meg Kay-Stacey about her article on hypersomnia, which appears in the August 2026 Continuum issue on the neurology of sleep. Meg, welcome to the podcast, and maybe you can begin by just introducing yourself to our audience. 
Dr Kay-Stacey: Yeah. Hi, I'm so glad to be here. So, like you said, I'm Meg Kay-Stacey. I'm a sleep neurologist at the University of Chicago. I'm also the AAN's Sleep Section vice chair. 
Dr Smith: Awesome. I didn't quite know what to expect in reading your article, except it was gonna be about people who are really sleepy. I was really amazed at how common these problems are, even, we'll get into this, disorders that I think of as being super rare. So, I know our listeners are gonna really enjoy hearing from you. I wonder if you could begin by just defining hypersomnia and maybe give us a flavor for the impact this has on patients who have primary disorders of hypersomnia. 
Dr Kay-Stacey: Yeah. I mean, so hypersomnia is really an excessive daytime sleepiness, so a feeling of excessive sleepiness, feeling like they can't stay awake during the day. And these patients' quality of life is quite impacted by these symptoms, and there's lots of different conditions that can cause it, but it can be quite detrimental to day-to-day living. 
Dr Smith: I honestly am sleepy a lot cause I work too hard or stay up late, and sleepiness seems to be a very common symptom. How do you sort out when a patient's excessive daytime sleepiness is pathologic related to lifestyle and the extent to which it may be a sleep apnea versus one of the other disorders that we'll talk about? 
Dr Kay-Stacey: Yeah. I mean, you really have to take a good history. So as neurologists, we know that, that we have to do that, but particularly a sleep history and really understand, first and foremost, how much sleep the patient is getting. Really important to understand, are they getting adequate sleep at night, right? Because chronic insufficient sleep can cause daytime sleepiness, right? And can make people appear like they might have a primary hypersomnia disorder when in fact they don't. So that's sort of first and foremost, and then it's assessing the other symptoms that they have. So, it's assessing nocturnal symptoms. You mentioned sleep apnea, so assessing for things like snoring and witnessed apneas, nocturia, and then assessing for what the quality of their sleep like. Is it refreshing? Is it not refreshing? How easy or hard is it to wake up in the morning? And then asking them again about daytime symptoms. Are you falling asleep inappropriately at work? Are, you know, you falling asleep while driving? Are you finding it hard to stay awake even after you've had a full night of sleep? To really try to differentiate what the symptoms might be from. And then it's also assessing things, sleep apnea, for example, physical exam findings. You know, are they obese? Do they have a larger neck circumference? Is the airway more crowded? And then we do have some measures, some scales, so there's the Epworth Sleepiness Scale that we'll use that assesses sleepiness, which is kind of a good way to at least initially assess how sleepy a patient might be during the day. 
Dr Smith: So that's great, and we'll talk a bit about sleep apnea, I hope. But when I hear hypersomnia, I always think about narcolepsy, and I wonder if maybe we can begin there. 
Dr Kay-Stacey: Yeah. 
Dr Smith: I was super interested to learn how common this is. About as common as myasthenia gravis. Actually, the population prevalence number is exactly the same as myasthenia. My Monday morning clinic is mostly myasthenia. So how do we recognize narcolepsy? Cause I'm worrying that I'm missing it. 
Dr Kay-Stacey: Yeah. So, narcolepsy, you know, there's two types. There's narcolepsy type 1 and narcolepsy type 2. So, narcolepsy type 1 is a little easier because you have cataplexy. But with both conditions, you're gonna see excessive daytime sleepiness. You're gonna ask about things like sleep paralysis, whether or not they're having sleep-related hallucinations, so hypnagogic or hypnopompic hallucinations. Are they having other sort of REM, intrusion phenomenon? You may also hear things like REM behavior disorder, so acting out their dreams at night, and then some degree of, you know, difficulty waking up in the morning, feeling like they need to nap. Naps are often more refreshing in patients with narcolepsy which is a feature that when we talk about idiopathic hypersomnia kind of helps to differentiate them. So, it's really just asking about sleepiness and assessing for these other symptoms that they can have associated with narcolepsy. 
Dr Smith: I was also interested to learn that narcolepsy is the most common cause of REM sleep behavior disorder in young patients, which is pretty cool. But I wonder, you used a term that I've never heard of, and I'm betting some of our listeners haven't, which is REM intrusion phenomenon. Could you tell us more about that?
Dr Kay-Stacey: Yeah. So, this is the idea that in narcolepsy, your sleep states are sort of, jumbled up, would be the way of thinking of it. You have these phenomenon where REM will persist into wakefulness. So, sleep paralysis is actually a perfect example of that, right? That you wake up and you feel like you're awake, but your body is still paralyzed, you can't move. Cataplexy is similarly a REM intrusion phenomenon, as are these hallucinations that I mentioned, the sleep-related hallucinations. 
Dr Smith: So what pearls do you have for recognizing cataplexy? What's the spectrum of cataplexy? 
Dr Kay-Stacey: Yeah. So, I think cataplexy, it's associated with emotion, right? And we most commonly think about it being associated with laughter, right, with positive emotion, but it's key to remember that it can happen with negative emotion too, with fright, being upset or angry. And usually when you're asking patients about it, you wanna phrase it to understand, are they having episodes where they feel like they have brief loss of muscle tone? And it can be subtle. It can be a head drop, their mouth opening, a hand dropping something, and it's brief. Usually it's seconds to just a couple of minutes. These aren't prolonged episodes, and they're not losing consciousness. They're awake, they're just having that brief loss of muscle tone. 
Dr Smith: So, what about orexin? I'm particularly interested in how often it's necessary to do an LP and look for CSF orexin levels. Is that a common thing in your practice, or do you rely on clinical phenomenology in a, you know, polysomnogram with multiple sleep latency testing to confirm a diagnosis of narcolepsy? 
Dr Kay-Stacey: Most commonly, you're gonna still do the PSG and the MSLT, obviously, because it's less invasive than doing the lumbar puncture. There are scenarios, right, where you may consider doing the LP. I think if someone has cataplexy and you're pretty confident in that and they have a positive PSG, MSLT testing done, you know, you really don't need the lumbar puncture, right? But if you're in that gray area that for whatever reason you have a really high suspicion they have narcolepsy, but for whatever reason the PSG, MSLT either couldn't be done or it was inconclusive, then I might think about doing the lumbar puncture. The other scenario is that there are some patients who have to be on REM-suppressing medications, like antidepressants, for example. In those patients, it can confound the results. And so, if you're not able to stop those for the MSLT testing, then that would be a scenario where I might use the lumbar puncture. Insurance is another reason that, again, if you have some of that inconclusive findings on the PSG, MSLT, that doing the lumbar puncture then can help to confirm the diagnosis, but only useful for type 1 narcolepsy, not type 2. 
Dr Smith: And type 2 is like type 1 but without cataplexy? 
Dr Kay-Stacey: Exactly. And then you kind of can think of it as sort of on a spectrum, I would say. There's sort of narcolepsy type 1, and there's idiopathic hypersomnia, and narcolepsy type 2 kind of falls in between. 
Dr Smith: Do you require the other core features of narcolepsy to make a diagnosis of type 2, like sleep paralysis, hallucinations? 
Dr Kay-Stacey: Right. You do. You don't necessarily have to have all of them, but you will see similar features, though most of them are more common in, in type 1 than in type 2. 
Dr Smith: So, I'm understanding you need to see, REM intrusion phenomena. 
Dr Kay-Stacey: Mm-hmm. Yes. 
Dr Smith: I love saying that. Makes me sound like I'm part of the sleep team. Now we're all part of the sleep team, aren't we? 
Dr Kay-Stacey: Yeah. 
Dr Smith: What about idiopathic hypersomnia? In reading about it and thinking about it, it sounds a lot like narcolepsy without those other features, but there, there are some differences. I wonder if you could give our listeners pearls into how to recognize that as opposed to maybe type 2 narcolepsy. 
Dr Kay-Stacey: Yeah. So idiopathic hypersomnia patients are also very sleepy during the day. They're more commonly going to describe that they sleep through the night, often for long hours, and that they wake up and still feel very unrefreshed. They'll have what we call, morning sleep inertia, or some people call it, you know, sleep drunkenness, where when they wake up in the morning, they feel like they're in a haze or a fog. It's really hard to get out of bed. They're often setting multiple alarms. And this is after having a full night of sleep, ten, twelve hours of sleep, and then they just feel tired and sleepy all day. If they nap, their naps will often feel unrefreshing, and when they take naps, they're often longer naps, and then they wake up and again will maybe feel some of that sleep drunkenness or inertia, and it makes it difficult for them to wake up. And then they don't have as many of the REM intrusion phenomena, but you still can sometimes hear things like sleep paralysis or the hallucinations in patients with idiopathic hypersomnia. And so that's where it does get tricky when you're trying to differentiate from narcolepsy. Really, the difference with narcolepsy and idiopathic hypersomnia when you do testing has to do with what you see on the overnight sleep study on the polysomnogram followed by that multiple sleep latency test. In the case of all three conditions, the MSLT should show a mean sleep latency of eight minutes or less. What separates narcolepsy from idiopathic hypersomnia is that in narcolepsy, the expectation's you'll have two or more sleep onset REM periods, so you go into REM sleep very quickly. Whereas in idiopathic hypersomnia, you'll have one sleep onset REM period or less. Traditionally, you'd think of that you wouldn't have any, but you theoretically could have one on that. So, that's sort of one way that we can differentiate the two. 
Dr Smith: That's really helpful, actually. Thank you. What about treatment? There are a whole bunch of different medications that you talk about in your article, including, medications that are in the pipeline, which is exciting. What's the treatment approach, maybe starting with narcolepsy? 
Dr Kay-Stacey: Yeah. So, with narcolepsy, there are more FDA-approved medications and options then there are for idiopathic hypersomnia, which is, you know, one of the things I hope will change over time with things that are in the pipeline. But with narcolepsy, traditionally often start first with an alerting agent such as modafinil or armodafinil to really help with those daytime symptoms. And then there are a number of other medications that can be used. Sometimes if the armodafinil, modafinil don't work, we'll advance into stimulant medications that are amphetamine containing. At night, there's a medication called sodium oxybate that you can take for narcolepsy. The low sodium oxybate is actually also approved for idiopathic hypersomnia. But sodium oxybate, the idea is that you're taking it at night, and it's helping to reduce the disrupted sleep that occurs in patients with narcolepsy, really kind of enhances slow-wave sleep at night and makes the sleep that patients are getting better quality, which then improves both excessive daytime sleepiness during the day as well as the cataplexy. And then there are some other medications, solrimfetol and pitolisant, that are also used in narcolepsy. I don't wanna necessarily get into the nitty-gritty of all of the mechanisms of action, but definitely read the article to learn more about that.
Dr Smith: So that's really helpful. What about cataplexy? Do these medicines also help with cataplexy, or is there a different approach for that symptom? 
Dr Kay-Stacey: Yeah. So, sodium oxybate definitely can be used, and the low-dose sodium oxybate can be used to help with the cataplexy. But then we'll also sometimes use medications in the antidepressant category as well. So, SSRIs, SNRIs, and tricyclic antidepressants can all also be used to help in the treatment of cataplexy. 
Dr Smith: And how about idiopathic hypersomnia? 
Dr Kay-Stacey: Yeah. So, for idiopathic hypersomnia, there are, you know, as I mentioned, less treatment options and not as many things FDA-approved. But, it was exciting, low-dose sodium oxybate was approved for idiopathic hypersomnia, so it's taken at night, similar to how it's used in narcolepsy, and does improve that excessive daytime sleepiness. And then we often will also use some of the other medications off-label, so modafinil, armodafinil, and the stimulant medications. But some of the other meds like the pitolisant and solrimfetol, those are not FDA-approved for the use in idiopathic hypersomnia. 
Dr Smith: So, I'm curious if we know what causes these conditions, so narcolepsy type 1, type 2, and idiopathic hypersomnia. I mean, the treatments all seem very kind of neuromodulatory in some way, you know, interacting with the REM system, for instance. What's the current thought regarding mechanism, underlying cause? 
Dr Kay-Stacey: So, narcolepsy type 1, it's due to the loss of orexin neurons in the hypothalamus. So that one is sort of the easiest of them that we know that those orexin-producing neurons are lost. There are thoughts that both with narcolepsy 1 and type 2, that there is autoimmune related concept and then also potentially some genetics, though it's not completely clear that it's one mechanism or another. But certainly, easiest is narcolepsy type 1 with that loss of orexin neurons. For idiopathic hypersomnia, we're not exactly sure actually what causes it. Again, some thoughts about maybe there being an autoimmune-related phenomenon for some patients, may begin for them after they've had infection, for example. And then some thoughts that perhaps GABA receptors are impacted in idiopathic hypersomnia. 
Dr Smith: Great. Well, that's super helpful, and I'm definitely gonna be on the lookout for narcolepsy. But let me pivot. I wonder if we might play a little bit of a game here. There's so many other things that cause hypersomnia, other disorders and situations, and rather than kind of march through them, I wonder if I could give you a name of a particular neurologic disease or situation and have you provide our listeners just a sentence or two about one thing they should know about hypersomnia in that disorder. You up for it? 
Dr Kay-Stacey: Sure. 
Dr Smith: So, let's begin with my backyard, myotonic dystrophy. 
Dr Kay-Stacey: Yeah. So myotonic dystrophy, we see an association actually with narcolepsy. So, certainly with patients with myotonic dystrophy, you'll see excessive daytime sleepiness, and should be screening them for narcolepsy. You should also be screening them for sleep apnea. 
Dr Smith: How about Parkinson's disease? 
Dr Kay-Stacey: Parkinson's disease, at least a third of those patients will describe excessive daytime sleepiness. They can also experience sleep attacks during the day, likely has to do with dopaminergic mechanisms. 
Dr Smith: So, I'm gonna ask a question in the middle of our game. So, in myotonic dystrophy, it's actually true narcolepsy. So, you would want to screen for that, and then if they meet the criteria, you would treat them similar to we spoke about earlier. All right. How about traumatic brain injury? 
Dr Kay-Stacey: Yeah. So traumatic brain injury, very common for patients to experience excessive daytime sleepiness. Those patients will also experience circadian dysregulation. So, when you're interacting, you know, with those patients, you definitely wanna get a good sleep history, understand is there a circadian component, or is it true excessive hypersomnia related to the brain injury? 
Dr Smith: How about multiple sclerosis? 
Dr Kay-Stacey: So, MS, not as common for it to be hypersomnia per se, more common to hear fatigue in these patients. I do think, again, sleep apnea is probably under-recognized in MS patients, so making sure you're screening for that. But not-- do not classically hear, you know, primary hypersomnia disorders, more so fatigue. But MS fatigue is treated similarly to some of our hypersomnia conditions, often use a modafinil or an armodafinil for that. 
Dr Smith: How about medications?
Dr Kay-Stacey: So, there's a lot of medications that can cause excessive daytime sleepiness, a lot of medications that we as neurologists give, right? We're very aware that our anti-seizure medications can potentially cause excessive daytime sleepiness. The antidepressants that we use to treat various neuropathic pain conditions and migraines can cause sleepiness. The antidopaminergic medications can cause sleepiness. Benzodiazepines can cause sleepiness. Muscle relaxers can cause sleepiness. So, lots of different, medications that we use to treat neurologic conditions can create sleepiness. 
Dr Smith: How about stroke? 
Dr Kay-Stacey: Stroke can cause sleepiness too. Also can cause fatigue, and sometimes it can be challenging to differentiate. There's also a higher incidence of sleep apnea in patients with stroke as well, so you definitely wanna make sure that you're screening for that. But yeah, depending on the location of the stroke too, that can also contribute to the sleepiness 'cause if it's anywhere sort of along the ascending reticular activating system, it could cause a problem.
Dr Smith: And maybe one more, depression. 
Dr Kay-Stacey: Yeah, so depression also can be tricky to differentiate from hypersomnia, and you do really wanna make sure when you're seeing these patients that you're assessing to make sure that it's not the depression that's causing them to be sleepy. You know, patients with depression will often spend long hours in bed and spend a lot of time sleeping, and so you do really kind of have to piece that together and figure out what's what. 
Dr Smith: Hey, that was fun, and I think we've probably convinced everyone who's listening to us that they probably should check out and read the article because guaranteed, no matter what you do in neurology, there's something in this article for you. One thing we didn't talk about, one of the kind of eight central causes of hypersomnolence that I thought worth kind of winding up with is insufficient sleep syndrome. I wonder if we might talk about this from the point of view of our listeners. And what advice do you have to neurologists and people who care for patients with brain disease regarding self-care and sleep self-care and not ending up with insufficient sleep syndrome? 
Dr Kay-Stacey: Yeah. Great question, and I think I have been thinking a lot about just sleep in general because sleep is so important to brain health, right? I know the AAN has been big proponents of the importance of sleep, and there was lots of talk about it at the annual meeting because of that. You know, the average adult needs somewhere between seven and nine hours of sleep per night. So, if you're getting less than that, you are at risk for insufficient sleep, and that insufficient sleep builds up over time. So, you can't recover from many months or years of insufficient sleep by sleeping for just one night. And so, it is really important to make sleep a priority because when you have chronic insufficient sleep, it can mimic some of these other conditions. You can see narcolepsy-like symptoms where you're falling asleep inappropriately, where it's impacting your quality of life, potentially impacting your ability to drive. So definitely very important to really try to target that seven to nine hours of sleep per night. And I think from a self-care standpoint, if you feel like you are getting that seven to nine hours of sleep per night and you're still feeling sleepy or still feeling unrefreshed or dozing off during the day, then you really should get assessed for an underlying sleep condition that might be causing you to feel that way. 
Dr Smith: So, Meg, this has really been such a great conversation, and it's a really great article. I wonder if we might wind up with one more question, which is if there was one thing our listeners should remember from our conversation, other than to kind of wait for their Continuum issue to arrive and immediately read this article, what would it be? What should they remember? 
Dr Kay-Stacey: I think that if a patient is telling you that they're sleepy or tired during the day, that you really need to dig in and figure out what it is. Is it something that they themselves are doing that's behaviorally induced? Is it something that's happening with their sleep at night? Or is it an underlying primary hypersomnia condition that you can treat, right? These conditions are treatable, and you can have really a significant impact on quality of life, which is, you know, the best part of our jobs when we can actually make our patients feel better. 
Dr Smith: Fantastic. Meg, thank you so much. I know that our listeners really enjoyed this. I know they'll enjoy the article as well. Thank you. Again, today, I've been interviewing Dr. Meg Kay-Stacey about her article on hypersomnia, which appears in the August 2026 Continuum issue on the neurology of sleep. Be sure to check out Continuum Audio episodes from this and other issues, and thanks to you, our listeners, for joining us today. 
Dr Monteith: This is Dr. Teshamae Monteith, Associate Editor of Continuum Audio. If you've enjoyed this episode, you'll love the journal, which is full of in-depth and clinically relevant information important for neurology practitioners. Use the link in the episode notes to learn more and subscribe. AAN members, you can get CME for listening to this interview by completing the evaluation at continpub.com/audiocme. Thank you for listening to Continuum Audio.

Insomnia affects neurologic health, quality of life, and daily functioning, but effective treatments are available. In this episode, Dr. Brandon Peters-Mathews discusses a practical approach to evaluating chronic insomnia, highlights the importance of identifying contributing conditions such as sleep apnea and mood disorders, and reviews cognitive behavioral therapy for insomnia (CBT-I), the recommended first-line treatment. Learn how addressing sleep can improve outcomes across a wide range of neurologic disorders.
In this episode, Katie Grouse, MD, FAAN, speaks with Brandon R. Peters-Mathews, MD, FAAN, FAASM, author of the article "Insomnia" in the Continuum® August 2026 Sleep Neurology issue.
Dr. Grouse is a Continuum® Audio interviewer and a clinical assistant professor at the University of California, San Francisco in San Francisco, California.
Dr. Peters-Mathews is the Section Head of Sleep Medicine at Virginia Mason Franciscan Health in Seattle, Washington.
Additional Resources
Read the article: Insomnia
Subscribe to Continuum®: shop.lww.com/Continuum
Earn CME (available only to AAN members): continpub.com/AudioCME
Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud
More about the American Academy of Neurology: aan.com
Social Media
facebook.com/continuumcme
@ContinuumAAN
Host: @BrandonPetersMD
Full episode transcript available here
Dr Grouse: Insomnia may be one of the most common medical issues experienced by patients, yet our knowledge about how to manage it remains limited. Today, I have the opportunity to speak with one of the world's leading experts on sleep disorders, Dr. Brandon Peters-Mathews, about the latest issue of Continuum on Neurology of Sleep. 
Dr Jones: This is Dr. Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. 
Dr Grouse: This is Dr. Katie Grouse. Today, I'm interviewing Dr. Brandon Peters-Mathews about his article on insomnia. This article appears in the August 2026 Continuum issue on Neurology of Sleep. Welcome to the podcast, and please introduce yourself to our audience. 
Dr Peters-Mathews: It's my pleasure to join you, and I'm happy to talk about this article. I think it's an interesting one for most folks. I am a board-certified sleep neurologist. I practice at Virginia Mason Franciscan Health in Seattle. I did my neurology training back at the University of Minnesota and my sleep training at Stanford University. I've been in practice for more than thirteen years at this point. It's hard to believe, but it's exciting to be able to speak with you today. 
Dr Grouse: This is definitely an important topic for everybody. Certainly, sleep and the lack of it affects all of our patients, and I can't imagine there's a single clinical neurologist who doesn't have to answer questions and help evaluate patients with this problem, so very high-yield topic for everyone. Now, having read your article, I'm curious if you had to choose one key point that you want the readers of your article to take away after reading it, what would it be? 
Dr Peters-Mathews: Emphasize for my patients that insomnia is a condition that we can work through and resolve, that if we really can understand the underlying contributing causes and resolve those issues, we can typically improve sleep. It's a process. It takes time. It takes some attention and, and sometimes even testing to figure out what's going on. But if we can dial into these root causes, we can typically help somebody to sleep much better. As part of that, we often employ a therapy called CBT-I, which we'll talk about here a little bit later. But that also helps us to identify some of these contributing factors that are leading to the poor sleep. 
Dr Grouse: And I definitely want to talk more about CBT, it's such an important topic. But even before we get into that, I'd love it if you could just walk us through a hypothetical case of a patient with insomnia. I think the type of patient that I think we've all seen in our clinical practice and somebody who says, "You know, I've had poor sleep. I've had insomnia for many years. I've tried all of the things you're supposed to try. You know, I've tried sleep hygiene. I've tried this. I've tried that. I've tried medications. Nothing seems to work." Could you walk us through how you would evaluate a patient like this and start to consider what to recommend?
Dr Peters-Mathews: So, some simple information that we can gather, would be information about when they're trying to go to bed, how long it's taking them to fall asleep initially. If they wake in the night and have trouble getting back to sleep, how often they wake in the night. If they're experiencing early morning awakenings, their final wake time, and when they actually get out of bed in the morning. That gives me a sense of the structure of their sleep pattern and whether or not they might be spending an excessive amount of time in bed for their own sleep need at their current age. The other factors that we might consider are sleep disorders, and typically, I would assess for other symptoms that would point me towards sleep apnea or restless legs and occasionally other disorders of sleep. We wanna make sure we're not missing comorbid conditions that might be affecting that person. These often include mood disorders. Sleep and mood walk hand in hand, and so anxiety and depression are important to identify and treat if present. We also want to make sure someone's not suffering from chronic pain or other conditions that might be impacting their sleep. So, I take a broad approach. I ask the same questions to each patient that comes to see me. I wanna make sure I'm not missing some of these details. And then some of these folks will require testing to further understand their sleep. Others may move on to a different therapy, and long-term may require even other interventions, including medications, to fully resolve their condition. 
Dr Grouse: You mentioned in your article circadian rhythm sleep disorders. How often are these really a factor in patients with chronic insomnia? And do you think that's something that we as kind of first-line clinicians should be screening for as well? 
Dr Peters-Mathews: So delayed sleep phase syndrome is the most common circadian disorder, and these are folks who are night owls by nature. They often develop their sleep patterns, as teenagers, if not before, and they may fade away in the working years but come back in retirement age. I would say that's a very common condition. It may affect as many as one in ten people. The other circadian disorders are pretty uncommon, so advanced sleep phase syndrome, where somebody is sleepy early and waking too early, that may only affect one in three hundred people. There are other conditions that affect specific populations, like non-twenty-four circadian pattern affects blind people. Typically, half of blind people have that condition. There are conditions that affect the regularity of sleep, so an irregular sleep-wake pattern that might occur more in folks with maybe an advanced dementia. So, there are populations where these conditions can be fairly common, but among the general population, that night owl tendency is by far the most common. 
Dr Grouse: That's really helpful. And just taking a step back, why is insomnia bad for us? So, we worry about this in our patients. We know it can make neurologic issues worse. But in general, like, what are the reasons that having poor sleep can affect our health?
Dr Peters-Mathews: Yeah, and it's not enough hours, certainly quantity, but also quality of sleep that matters. And I tell people that sleep is a pillar of health, just like nutrition and exercise. It's the other main contributor to our health and well-being. And so, it has its fingers in almost every aspect of our health. Insomnia on its own is a risk factor for other psychiatric conditions, including depression, anxiety, even disorders like bipolar and schizophrenia. Folks with insomnia are more likely to have alcohol or drug abuse issues and are at higher risk for things like chronic pain, suicide and, and social and occupational dysfunction. So, it's a disorder that has a really profound effect on how someone functions during the day, and again, may take a toll on their health over time. 
Dr Grouse: That makes sense, and I would assume that there are certain populations within our neurology practices where we should really be attuned to the risk of insomnia. Are there specific populations you'd recommend really make it a habit of screening for insomnia? 
Dr Peters-Mathews: I was joking with someone recently that anyone with a neurological nervous system can have issues, impacted by poor sleep. There are certain groups, so chronic headache patients are perhaps one that might warrant a further evaluation and management. Folks with multiple sclerosis or Parkinson's may have physical conditions that lead to more discomfort in sleep, fewer movements of their body in sleep, issues around nocturia that would disturb their sleep. Certainly, those with dementia, Alzheimer's disease and other dementias. Parkinson's and Lewy body dementia overlap a lot, as does multiple system atrophy. That can point us towards other conditions like REM sleep behavior disorder, but also insomnia can be an important feature of those disorders as well. And then folks with stroke often have disturbance to their sleep and may develop insomnia after experiencing a stroke. So those are specific populations where I think the yield is high to be looking for insomnia and other sleep disorders. 
Dr Grouse: Yeah, that makes sense. I think a lot of us think of insomnia as almost like, make sure we're not missing this as sort of a mimic of the problem, when in fact it's probably just more part and parcel of the problem and something we need to be thinking about treating as part of their disorder. So helpful to think about it in that light, at least in my own mind. Now, I want to get a little bit back to some of the therapies you've recommended, and I think first just stopping again at sleep hygiene. Your article has a really great list, I think, of sort of like a checklist of actions that people should be taking to make sure that they are managing their sleep hygiene well. And I definitely recommend our listeners look to that. How often do you think that focusing on sleep hygiene helps when you get a patient who says, "Hey, I have got terrible sleep. You know, what do I do?" 
Dr Peters-Mathews: It's pretty common for people to have access to this information through their own reading online, and most folks have worked through this by the time they've come to see me, and often a primary care provider or specialist may have given some of this guidance as well. It's pretty rare for them to not recognize something as obvious as having caffeine too late in the day by the time they're coming to my attention. The sleep hygiene generally is used as a control when we do research to look at how something like medication is working or CBT-I might be working. It's the comparative control. It's almost like the null intervention. So, it's not highly effective, and if folks are not finding it helpful, they've made those adjustments to their sleep environment or their habits, and they're continuing to have issues, there's typically more that needs to be done, and that's where CBT-I really comes in as a strong intervention for those people. 
Dr Grouse: And then getting on the topic of CBT-I, so helpful. I'm really glad that your article spent a lot of time talking about it as really a truly high-yield, great intervention for insomnia. And I really felt that the question shouldn't be: When is cognitive behavior therapy for insomnia helpful? But like, when isn't it helpful? What are your thoughts about that? 
Dr Peters-Mathews: Yeah. I always point out that the American College of Physicians has recommended CBT-I for adult patients as the initial treatment for chronic insomnia even before the use of a medication for nearly ten years. That recommendation came out in July of 2016. So, there are folks who may not be good candidates for it, who may be screened out because of other conditions that they have, and there certainly are folks who don't do as well with CBT-I. And adherence is important. Somebody needs to be able to follow the instructions and apply that to their lives. And certainly, there are a number of things that could interfere with that compliance. I would say untreated anxiety and pain are two things that often trip people up. It's like running a race with a broken leg. Despite their best efforts, if those are not addressed, they will continue to have issues around insomnia. And then one thing that often is unrecognized and may be missed is untreated sleep apnea. That is a common contributor to a chronic insomnia, especially in older folks, women beyond the age of menopause and men even starting in middle age, thirties and forties. We don't want to miss sleep apnea. Even insomnia that's, "I can't fall asleep at the beginning of night," that could still be sleep apnea, so that's something I really emphasize with my patients. 
Dr Grouse: Really great reminder about sleep apnea for sure. Something that always is beneficial to make sure we are not missing. Oftentimes I'll bring up a CBT for insomnia, and what is that? Like, what would we actually do, and what is a high-level overview of what happens with CBT-I? 
Dr Peters-Mathews: Yeah. So, I generally tell my patients that this is a six-week program. It's a structured program, almost like a boot camp for sleep, in which we are addressing underlying causes, recognizing what those are and, and working through those underlying causes. There is often tracking using a sleep log or sometimes wearable data.To guide decisions that are made in the program. It's very goal-directed, science-based therapy. We often introduce concepts around sleep drive, circadian rhythm dealing with a busy mind at night. There's concepts of mindfulness and relaxation training that are introduced. People often are able to taper or stop using sleeping pills as part of this therapy. And the nice thing is they walk away with a set of skills that they can apply the rest of their lives to sleep more normally. And so, there's good research that suggests even years after someone's completed a CBT-I course, they continue to sleep more normally. They have the tools that they need to sleep better even years beyond that education. 
Dr Grouse: You know, this just sounds so great. It almost sounds like why wouldn't someone benefit from this? But of course, like I would imagine many institutions experience, I've definitely run into difficulties with access for my patients for CBT-I, and we have long wait lists. And I imagine there's many places where there just aren't even any specialists that patients can get to, to help with this. What are the resources that our listeners can take advantage of for their patients to get access to these types of therapies? 
Dr Peters-Mathews: So, one thing I tried to really emphasize in the article is that there are resources that can be drawn in. I'll give you some examples. So, at our institution, we have three sleep specialists, full-time sleep specialists, who trained at Stanford to become CBT-I specialists, and so we have more resources than probably most institutions would have. We do shared medical appointment workshops so that we can manage the number of patients that we have to see. And, and unfortunately, not everybody has that opportunity. You might plug into resources in your community, and one of the resources I point to in the article is the International Directory that's managed by the University of Pennsylvania that has eight hundred and seventy-five CBT-I specialists listed with contact information, et cetera. And I think that's an amazing opportunity to access this therapy. Unfortunately, there are countries and certainly states that do not have a specialist, that there's no one in the state that provides this therapy. And then we need to extend other resources, and that could be online treatment programs that can be done independently, bibliotherapy, so accessing books that could guide people through the therapy, even accessing other apps and maybe even wearables that pair with an app that could provide some of this guidance. The Veterans Administration worked with Stanford and worked with the National Center for PTSD and developed an app called CBT-I Coach that is free and can be downloaded and, and gives, I think, good education, good guidance. So, there are resources that exist. It's somewhat finding what might work for your individual patient, how they're preferring to access this or their learning preferences. Do they want to read a book or not? And getting them into the right pathway. 
Dr Grouse: And I think that gets me into a whole other Pandora's box of the fact that they're already out there in the world are tons of different apps, wearable devices, all sorts of things that promise that they can help us with sleep, some that may have more, I think, data and evidence behind them than others. Do any of these apps or wearables in your mind show promise in our patients helping our patients track and diagnose and manage their insomnia? 
Dr Peters-Mathews: Yeah, there's a lot out there, and unfortunately, some of these devices actually can make sleep worse. People can develop a condition called orthosomnia or straight sleep, where they're trying to perfect their sleep and their sleep numbers, their metrics, and the wearables feeding them data that they continue to try to improve upon. And that fixation on those metrics can actually make their sleep quite a bit worse. A lot of these wearables and apps and other resources have not been well-studied. There's not research trials showing outcomes comparing to other standards of care. I would say the basic guidance of CBT-I, which many of these programs are based on, I think will be helpful to the majority of folks who are able to engage and complete that education. A lot of these are not dependent on that sort of framework or structure so that we may not actually be using the standards of CBT-I to try to improve sleep. They may be connecting you with other resources, like listen to this sleep story or this relaxation file or do some meditation, et cetera, which again, may be of some benefit, but it is not the same as a structured CBT-I experience. So, I think there are a few good resources that we highlight within the article, and I think there are probably others coming that may give individuals a more individualized, directed approach to managing their sleep issues. But it's almost like going to the App Store and there's thousands of apps. It's hard to know which one might be most based on science or the most beneficial to that individual. 
Dr Grouse: Well, I really appreciate in your article that you did have a great list of apps and things along those lines to try, so I do encourage our listeners to check that out as well. Some really, really great resources there in the article in many different areas. Now, I wanted to turn the conversation to a slightly different thing, which is medications for insomnia. Now, when are medications appropriate for treating insomnia? When should we be thinking about turning to these for our patients? 
Dr Peters-Mathews: So again, we would suggest that CBT-I would be first, and that failing improvement with CBT-I, that medications would be extended to a person affected by insomnia. And over-the-counter options as well as prescription medications might be used. Unfortunately, that's not how things unfold in the real world. Many people are jumping to medications first, whether that be an over-the-counter supplement or other medication, or they're seeing primary care and other specialists who's providing them a prescription for sleep aid. So there's data from the CDC going back to twenty twenty that suggests that about six point three percent of adults were taking a sleeping medication every day in the months prior to the survey. And women who were older than sixty five, white women, were more likely to be using a sleeping medication every day. That number was 13.5 percent of those surveyed. So, lots of folks are on medications, and certainly melatonin is widely used. Unfortunately, it's not regulated by the FDA in a sense that we don't have exact concentrations controlled. So, people can take melatonin that has no melatonin in it. They might take melatonin that's forty or more times the dose. There's variance within lots from the same manufacturer. There's a lot of trouble knowing exactly what you're getting when you try to take something like melatonin over the counter. Other sleep aids that we might reach to over the counter, like variants of diphenhydramine or doxylamine, and these are often the PM drugs that we think about. They have risks associated with population-based studies which suggest risk of dementia, risk of falling, risk of mortality with these drugs, especially in older populations. So again, that would give us potentially pause. The prescription medications that we go to, there are some that the American Academy of Sleep Medicine would recommend as more beneficial than harmful, and some are good for both initiating and maintaining sleep. Some have such a short half-life that they're really best as initiation drugs. And then others are better for maintenance of sleep, so reducing awakenings and wakefulness in the night. My own individual take, often people are coming to me on medications, typically over the counter, but often prescriptions, and have even tried and failed many of those medications before they finally come to see a specialist. And so, I don't often reach to medications until I've exhausted CBT-I, until we've completed a sleep test to make sure we're not missing something like sleep apnea, until we've ruled out some other potential contributing causes. But there are patients I have who really will not sleep without medication support and sometimes even multiple medications that work in complementary ways to try to normalize their sleep. And so, in some cases it is necessary, but it is not meant to be a first line for anyone. 
Dr Grouse: Yeah, and I think all of our listeners can relate to the fact that we often see patients who've been on sleep medicines for many, many years and take them every night. It's good to know that there is sort of a procedure here to consider and perhaps again, back to the plug to CBT-I as being the right starting point to see if there's some that we can help get off of these meds, although, as you mentioned, maybe not always going to be successful. Well, I really appreciate our conversation about this. It's been really great to read this article about insomnia. Again, I encourage our listeners to check it out. Some really great resources for many different therapies, thinking about other alternative diagnoses and different medical conditions where insomnia really needs to be considered. And I really appreciate you writing this article. It's been a pleasure to talk with you today. 
Dr Peters-Mathews: It's my pleasure to share this information with folks, and I hope that you find it useful in your clinical practice or even your personal life as the need arises. 
Dr Grouse: Again today, I've been interviewing Dr. Brandon Peters-Mathews about his article on insomnia. This article appears in the August 2026 Continuum issue on Neurology of Sleep. Be sure to check out Continuum Audio episodes from this and other issues, and thank you to our listeners for joining today. 
Dr Monteith: This is Dr. Teshamae Monteith, Associate Editor of Continuum Audio. If you've enjoyed this episode, you'll love the journal, which is full of in-depth and clinically relevant information important for neurology practitioners. Use the link in the episode notes to learn more and subscribe. AAN members, you can get CME for listening to this interview by completing the evaluation at continpub.com/audiocme. Thank you for listening to Continuum Audio.

Central sleep apnea is a complex and often underrecognized sleep-related breathing disorder that differs from obstructive sleep apnea by involving reduced respiratory drive rather than upper airway obstruction. In this episode, Dr. Ran Liu reviews the underlying mechanisms of central sleep apnea, including the role of ventilatory control instability, discusses its association with neurologic conditions such as stroke, multiple sclerosis, ALS, and myasthenic disorders, and highlights key considerations for diagnosis and management. Learn how emerging technologies, personalized treatment strategies, and advances in sleep medicine are improving outcomes for patients with this heterogeneous group of disorders.
In this episode, Teshamae Monteith, MD, FAAN, speaks with Ran R. Liu, MD, FRCPC, MSc, author of the article "Central Sleep Apnea" in the Continuum® August 2026 Sleep Neurology issue.
Dr. Monteith is the associate editor of Continuum® Audio and an associate professor of clinical neurology at the University of Miami Miller School of Medicine in Miami, Florida.
Dr. Liu is an Adjunct Clinical Assistant Professor at McMaster University in Hamilton, Canada, and an Adjunct Lecturer at the University of Toronto in Toronto, Canada.
Additional Resources
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Host: @headacheMD
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 Full episode transcript available here
Dr Monteith: You may be familiar with obstructive sleep apnea, but central sleep apnea is often less understood and frequently underdiagnosed. In this podcast, we break down the key clinical pearls to sharpen your diagnostic reasoning, discuss why central sleep apnea matters, and to explore some of the fascinating advances transforming the field.
Dr Jones: This is Dr. Lyell Jones, editor-in-chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. 
Dr Monteith: This is Dr. Teshamae Monteith. Today, I'm interviewing Dr. Richard Liu about his article on central sleep apnea. This article appears in the August 2026 Continuum issue on Neurology of Sleep. Welcome to our podcast. How are you? 
Dr Liu: Good. Thank you, Dr. Monteith, for having me today. 
Dr Monteith: Please introduce yourself to our audience. 
Dr Liu: Hello, everybody. My name is Richard Liu. I am a sleep neurologist. I am working out of Toronto at both Sunnybrook Health Science Center and MedSleep. I did my residency at Queen's for neurology and my sleep medicine fellowship at Harvard University. 
Dr Monteith: Great. And what got you interested in sleep? 
Dr Liu: Thank you very much for asking. For me, sleep medicine is a field where essentially everything is connected. Certainly, impaired sleep can affect many other conditions, including many neurological conditions. And even within sleep medicine, when somebody has a sleep disorder, often the entire system is connected. So as an example, if you have insomnia and fragmented sleep and periodic limb movements of sleep, certainly these conditions can impact sleep apnea. And certainly, for today's topic of central sleep apnea, this is an extremely complicated disorder where it's a very in-depth integration between neurological and respiratory physiology, among other systems as well. 
Dr Monteith: So, I guess you're kind of like the cornerstone, sleep being the cornerstone of neurology. Everyone has to sleep. That's for sure. Great. So why don't we talk about what central sleep apnea is, and how prevalent is it as a collective group of disorders compared to obstructive sleep apnea? 
Dr Liu: So, one way to think about central sleep apnea is that this is a heterogeneous group of etiology. But the primary concept here for central sleep apnea is that there's a reduction in respiratory drive. This is in contrast to obstructive sleep apnea, where essentially this is some form of airway obstruction in the presence of relatively intact respiratory drive. And of course, there's mixed apneas where they may contain features of both. But of course, now we know that even obstructive sleep apnea, there's a certain degree of drive dependence somewhat blurring these distinctions. The overall prevalence of central sleep apnea is about five to ten percent of all patients with sleep- disorder breathing. And certainly, it could be higher in some neurological conditions, such as things like stroke, multiple sclerosis, and multisystem atrophy. 
Dr Monteith: Great. So certainly, it's out there. Why don't you tell us about the objectives of your article? 
Dr Liu: Absolutely. Thank you for asking. I think the main objective of this article is really to highlight that central sleep apnea is a complex syndrome resulting from a large group of heterogeneous etiologies. And of course, again, it could be associated with many neurological conditions. And really here, I want to highlight advancements, both medicine and technology, on both the side of diagnosis of central sleep apnea, as well as the multimodal targeted treatment. 
Dr Monteith: And what do you want our listeners to take away from this talk and certainly your article? What are the key essential points? 
Dr Liu: Thank you very much for asking. I think that one way of looking at central sleep apnea to etiologically divide this into both hypocapnic and hypercapnic central sleep apnea. And of course, loop gain being a major driver for a hypocapnic central sleep apnea, and that one can actually think about hypocapnic central sleep apnea beyond a phenotypic spectrum with obstructive sleep apnea, with many patients having overlapping features of both obstruction and central component. On the other hand, hypercapnic central sleep apnea, often also known as hyperventilation syndrome, can span etiology from chemoreflex dysfunction to a broad range of neuroanatomical localization, such as central nervous system, peripheral nervous system, neuromuscular junction, and muscle disorders. 
Dr Monteith: And what are some of the symptoms of central sleep apnea? Do any of them differ from obstructive sleep apnea? 
Dr Liu: Thank you for asking, that's an excellent question. So certainly, central sleep apnea symptoms can overlap with obstructive sleep apnea symptoms. And of course, given the large range of underlying etiology, often the CSA symptoms depend on the underlying etiology. There may be less snoring compared to obstructive sleep apnea patients, especially the hypocapnic CSA patients. Of course, these patients, like OSA, may have frequent awakenings, gasping and choking their sleep, and nocturia, and so on.These patients may have daytime sleepiness, insomnia-like symptoms, or they could be asymptomatic. Interestingly, the hypocarbnic central sleep apnea patients, they're a bit more prone to have the insomnia-like symptoms, whereas the hypercarbnic central sleep apnea patients, they tend to have a bit more of the daytime sleepiness and morning headaches. 
Dr Monteith: You spoke about some of the neurological disorders that might be associated with central sleep apnea, like stroke and multiple sclerosis. What about some of the more traditional risk factors associated with obstructive sleep apnea or conditions associated with it, like obesity and hypertension? Or does that just mix the picture? 
Dr Liu: There is many overlap between risk factors between obstructive sleep apnea and central sleep apnea, and certainly one of the things that I highlight in this article is really that often it's not just black and white, that this could be a spectrum with overlapping disease between both conditions. So certainly, in our neurological world, stroke is the most common thing that may be associated with central sleep apnea. But overall, cardiovascular issues such as heart failure, atrial fibrillation, these things can also be associated with central sleep apnea. And again, from the neurological perspective, if we were to divide from hypocarbnic versus hypercarbnic central sleep apnea, by thinking about the hypercarbic central sleep apnea, again, this is where we're thinking about hypoventilation syndromes. You know, anything that can cause neuromuscular weakness, this is something that we should have a high alarm for, that potentially there may be a hypoventilation component. So, things like any myasthenic syndromes and ALS. 
Dr Monteith: Great. Why don't we also talk about the classification? When was the last time central sleep apnea's classification was updated, and what should we know about the classification? 
Dr Liu: The most recent classification for central sleep apnea is written in the International Classification of Sleep Disorders, third edition. In this edition, it's classified with six central sleep apnea syndromes. So, these are the CSA with Cheyne-Stoke breathing, CSA due to high altitude periodic breathing, primary CSA, CSA due to medication or substance, CSA due to medical disorder without Cheyne-Stoke breathing, and treatment-emergent central sleep apnea. These classifications more so describe the circumstance of when CSA occurs. A more etiological classification that we can consider would be classifying them by the underlying pathophysiology, which is dividing this from hypercarbnic central sleep apnea versus a hypocarbnic central sleep apnea. Certainly, both set of classification are discussed in this article. 
Dr Monteith: Yeah. You discussed at length, the major physiological factors that our audience is just going to have to read. I don't want them to hear this too much while they're driving or on the treadmill, cause its super high level. But why don't we just start with some very basic factors that we need to know about this circuitry? 
Dr Liu: Perhaps I can start with this concept of loop gain, which is the most important concept under hypocarbnic central sleep apnea. For any one of my colleagues who's listening to this, they're probably laughing right now cause they think that loop gain is my favorite word. So, loop gain is an engineering term referring to the sensitivity of a feedback loop. So, in the context of sleep medicine, this is an overly sensitive respiratory control to carbon dioxide and oxygen fluctuation. There are three components. The main one is controller gain. This is a chemosensitivity predominant to CO2. The second is plant gain, which is the lung's effectiveness for carbon dioxide excretion. And the last is what's called the mixing gain. This is circuitry delay from the time the signal travels from the pulmonary artery to the peripheral and central chemoreceptors. So conceptually, one may think, let's say something decreases your ventilation, so for example, apnea or hypopnea. With this, as you can imagine, when you stop breathing, your CO2 builds up, and this builds up according to the curve of the plant gain. And of course, this build of CO2 signal takes time to go from your lung to your chemoreceptor. That's your mixing gain. And of course, here it meets the overly sensitive chemoreceptors. This is your controller gain. As a result, this results in amplification of your ventilation to the initial respiratory disturbance. So, you have a overshoot of ventilation. All of a sudden, you're blowing out too much carbon dioxide, then you become hypocarbnic. At one point, if you blow out way too much carbon dioxide, your CO2 goes below what's called a PCO2 apneic threshold. After this, if your CO2's below, you essentially stop breathing. And of course, after that, you can imagine your CO2s are building up again. So, when this loop goes over and over, you generate what's called a chemoreflex-driven respiratory oscillation, where you create a crescendo, decrescendo-like flow pattern, which is underneath what we see in periodic breathing in central sleep apnea. 
Dr Monteith: So, without going into too much detail, what is the key way to target restoration of equilibrium? Are there anatomical targets, physiologic targets that we're trying to manipulate here?
Dr Liu: Again, thank you very much for that wonderful question. There's certainly many approaches that we could do to improve the stability of the system. Certainly, there are treatments for ventilation, either CPAP or in the case of hypocarbon central sleep apnea, things like adaptive servo ventilation. There is also medications that we can certainly discuss later that can double down the entire system for loop gain. Positional therapy can help for many of these patients. For the appropriate patient, improving their arousal threshold can actually reduce arousal-induced amplification of loop gain. Many of these patients, again, if appropriate, certainly weight loss may be helpful, and these are among many things that we can potentially do to improve the ventilatory stability of these patients. 
Dr Monteith: Okay, great. But let's also talk about the general overall approach to diagnosing, and much of it is by history, as you mentioned. There's also sometimes a need, as you say, to differentiate out how much is obstructive. So, what is the thinking process there when you're approaching a patient? 
Dr Liu: So perhaps I can start with in terms of the diagnostic modalities that we could use for this. So, the gold standard for diagnosis of central sleep apnea is still our polysonogram. The home sleep apnea test sometimes may be harder to distinguish between obstructive and central events. In addition, on a PSG, you have EEG. This allows you to assess for sleep quality and arousals, as well as the EMGs, which can help you pick up periodic limb movements of sleep. And of course, all of these things themselves can affect the central sleep apnea and can be a potential treatment factor. 
Dr Monteith: Before we get into treatment, can you just give us, like, the top five or six drugs or drug classes we need to look for so that, you know, we can discontinue or try something else for our patients that might be complicating their presentation? 
Dr Liu: Certainly medications, in some cases, can help central sleep apnea, but other cases can certainly be a precipitant of central sleep apnea. So, one thing to consider would be opioid medication. They can certainly cause very complicated central sleep apnea, something called ataxic breathing, where you have irregularity to the tidal volume and the rate of breathing. Other medications such as Oxybate, baclofen, valproic acid, gabapentin, all of which can certainly contribute to central sleep apnea. And of course, in the stroke world, something that we should always think about is that Tetagelor can also contribute to central sleep apnea. And outside of this, things like muscle relaxants, anesthetic agents can also be a contributor. 
Dr Monteith: Great. Now let's get into some of the treatment. 
Dr Liu: I like to divide treatment into targeting a hypercarbnic central sleep apnea and a hypocarbonic central sleep apnea. For hypocarbonic central sleep apnea, the first line is CPAP treatment. But for many patients, CPAP therapy is insufficient. There's also adaptive servo ventilation, which is an advanced device designed for hypocarbonic central sleep apnea. For hypercarbic central sleep apnea, again, first line is CPAP treatment, with more advanced devices being a bilevel therapy as well as volume-assured pressure support ventilation. There are also medications that can reduce loop gain, with the most researched one being acetazolamide. We can also reduce arousal thresholds, which could be appropriate for certain patients. And for certain patients, improving arousal threshold can be helpful as, especially in hypocarbic central sleep apnea, that arousals can amplify loop gain. Weight loss can be helpful for both hyper- and hypocarbonic central sleep apnea, and we have great new medication on the market for this. Other therapy can include supplemental oxygen that can be added to PAP devices, as well as phrenic nerve stimulation, positional therapy, as well as carbon dioxide modulation. 
Dr Monteith: Excellent. So, it sounds like there's a lot of opportunity to help patients. Now, what are you most excited about in terms of latest development for detection as well as for intervention? 
Dr Liu: Thank you very much. I'm actually excited about many things in sleep medicine. Perhaps the thing that I'm most excited about in detection in sleep medicine would be the wearable technologies. So, these technologies may use photoplethysmography to detect peripheral artertonometry. This is where we're measuring the pulsatile arterial volume signals as a surrogate of cardiac and respiratory function. And when paired, that was often desaturation. With these technologies, we can actually detect the staging, autonomic arousals, and HI. So of course, these technologies do not have flow, and they do not have EEG. But they're very powerful technology that allows us to do multi-night testing from home. And of course, understanding both the potential limitation of these technology in the context of patients can be very useful. In terms of treatment-wise, we're learning so much about the underlying contributing drivers of different forms of central sleep apnea. So again, this is highlighted in my article that many of these patients needs multimodal targeted treatment, both between either a PAP device in addition to other things such as medication, oxygen, positional therapy, and so on. 
Dr Monteith: Great. So, I mean, I think there's so much to this field. Your article is very extensive. Thank you very much for writing this. I know it may have taken a bit of time, and I appreciate you being on our podcast. 
Dr Liu: Thank you very much. 
Dr Monteith: Again today, I've been interviewing Dr. Richard Liu about his article on central sleep apnea. This article appears in the August 2026 Continuum issue on Neurology of Sleep. Be sure to check out Continuum Audio episodes from this and other issues. And thank you to our listeners for joining today. 
Dr Monteith: This is Dr. Teshamae Monteith, Associate Editor of Continuum Audio. If you've enjoyed this episode, you'll love the journal, which is full of in-depth and clinically relevant information important for neurology practitioners. Use the link in the episode notes to learn more and subscribe. AAN members, you can get CME for listening to this interview by completing the evaluation at continpub.com/audioCME. Thank you for listening to Continuum Audio.

Advances in sleep technology are transforming how neurologists identify and manage obstructive sleep apnea, a condition that affects up to 70% of patients with certain neurologic disorders and can negatively impact cognitive and neurologic outcomes if left untreated. In this episode, Dr. Joyce Lee-Iannotti discusses the growing role of wearable and nearable sleep-monitoring devices, when home sleep studies are appropriate, and how emerging technologies are expanding access to diagnosis and treatment. Learn practical strategies for screening patients, interpreting sleep data, and partnering with sleep specialists to improve long-term neurologic health through better sleep.
In this episode, Casey S. Albin, MD, FAAN, speaks with Joyce K. Lee-Iannotti, MD, FAAN, FAASM, author of the article "Sleep Diagnostics and Monitoring Technology in Obstructive Sleep Apnea" in the Continuum® August 2026 Sleep Neurology issue.
Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia.
Dr. Lee-Iannotti is a Professor of Neurology at the Barrow Neurological Institute, University of Arizona College of Medicine, and Creighton School of Medicine in Phoenix, Arizona.
Additional Resources
Read the article: Sleep Diagnostics and Monitoring Technology in Obstructive Sleep Apnea
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Host: @caseyalbin
Guest: @jleeiannotti
Full episode transcript available here
Dr Albin: Through the neurology of sleep issue, I think we have all been convinced that we all need better sleep, both for ourselves and for our patients. And fortunately, there is an abundance of new technology that can enable us to diagnose sleep problems, and then also make sure that our patients are getting the rest that's going to give them the best chance at a good cognitive recovery, and improve their cognitive function even if they are not currently suffering from a neurologic condition. Today, I am so excited to dive deeper into this topic. 
Dr Jones: This is Dr. Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. 
Dr Albin: Hello, this is Dr. Casey Albin. Today I'm interviewing Dr. Joyce Lee-Iannotti about her article on sleep diagnostics and monitoring technology in obstructive sleep apnea. This article appears in the August 2026 Continuum issue on neurology of sleep. Welcome to the podcast, I'd love to just start by having you introduce yourself to our audience. 
Dr Lee-Iannotti: Sure. Thank you so much for having me, Dr. Albin. I'm Joyce Lee-Iannotti. I'm a professor of neurology at Barrow Neurological Institute. I am boarded in general neurology, stroke, and sleep, but I spend most of my time in the sleep world, so I jokingly say that I get more sleep doing sleep than I certainly did in stroke. 
Dr Albin: Absolutely. I mean, wow, what a fascinating career, and I suspect that we're actually gonna get to some of how all of those pathophysiologies might overlap in the world of sleep. But you had the really exciting task of trying to distill this exciting, rapidly evolving field of sleep diagnostics, and I suspect it's relevant to many of the patients who end up in the neurology clinic, and I suspect that it's actually pretty relevant to many of our listeners who themselves might actually be wearing sleep tracking devices. And all of us probably wonder, well, how can we use that data to improve our own cognitive function and certainly make our patient's life even better? Before we even get into some of the meat and potatoes of this, I thought it would be really helpful for us to define some terms that come up in your article, one of which is wearables. We might figure that out, but the other is nearable. Walk us through what's a wearable, what's a nearable, how are they different? 
Dr Lee-Iannotti: I'm happy to do that. First of all, the article is entitled Sleep Diagnostics and Monitoring Technology, and this was a super fun article for me to write because it's very practical, and it's generalizable to everybody. So, I'm going to start with a wearable, and a wearable is really a device that is simply worn on the body. And we're all familiar with wearables like smart watches, they're rings, they're patches, they're headbands, and the most validated form of a wearable that you've probably heard about is actigraphy, which we use in the sleep clinic. 
Dr Albin: Tell us a little bit more. So, what is actigraphy? I've heard the word before, but don't actually know what it means. 
Dr Lee-Iannotti: Actigraphy has been a tool that we've used in the sleep clinic for a really long time. Traditionally, we used it to monitor circadian rhythm patterns in people who are night owls or morning larks. And then more currently, we actually use it to track sleep patterns in people with suspected narcolepsy. So, before they come in for a sleep study, we actually have them wear an actigraphy for about a week just to get a sense of their sleep duration and their circadian pattern. 
Dr Albin: Got it. And what is it monitoring? Our movement or the patterns that we may or may not make? 
Dr Lee-Iannotti: It's really based on movement. You're exactly right. 
Dr Albin: Cool. Okay, so most of this is based on gold standard monitoring with actigraphy. What other things can be incorporated into these wearable devices? 
Dr Lee-Iannotti: Yeah, the technology is really advanced, and every day it changes, which is super exciting. So, on top of movement, these wearables can look at temperature. They can look at even EEG, like limited EEG, heart rate variability, and a really big word that we like to use in sleep technology, which is PPG, or photoplethysmography data, and that's really looking at heart rate variability and oxygenation, saturations, and following those levels as well. 
Dr Albin: Wow, so you basically can get most of the data that you might have historically needed to go to a sleep lab to get. 
Dr Lee-Iannotti: Most of them. They're still a surrogate. You'll hear me emphasize in the article as well that the gold standard remains the in-lab polysomnogram, but these are good surrogate markers that patients can wear long term to look at trends and patterns. 
Dr Albin: Absolutely. And we're gonna unpack a little bit about who specifically those are best for and, really what it gives you in the clinic. But before we jump into that, what's a nearable, and how is that different? 
Dr Lee-Iannotti: Yeah. Nearables are really exciting too. So, these are devices that monitor sleep but don't require direct contact on the body. So, these are devices that our patients will use, but it'll be at the bedside table. They're devices that actually go underneath the mattress, or they can be in, like, the ambient environment to detect sleep patterns. 
Dr Albin: Oh my gosh. How is it doing that if it's not actually something you're wearing?
Dr Lee-Iannotti: I know. It seems a little Big Brother-ish, doesn't it? 
Dr Albin: Yes. 
Dr Lee-Iannotti: So, they use a technology called radio frequency signals, sometimes radar, sometimes sonar, pressure sensors, even microphones, and they're picking up things like respiration, movement, snoring, and that's how they can decipher sleep patterns. 
Dr Albin: Crazy. I mean, I guess the benefit of that is that it's less disruptive to the user 'cause it's not actually on them and having contact with them, and I suspect there's probably some downsides in terms of just it's a more limited data set you're getting. 
Dr Lee-Iannotti: Absolutely. Yeah, you're exactly right. It's more convenient because it's not touching them, so, in theory, they're gonna sleep more comfortably. But I would like to think that the most validated forms of devices that we use to track sleep have to have some form of contact with the body, and this technology is new and probably needs a few layers of more sophistication to be as accurate as the wearables. 
Dr Albin: Absolutely. I feel like we're going to have this conversation in five, maybe even less than that, years, and this data will have become like, oh, we all have something in our room that's monitoring everything. The world is crazy. All right. One of the places where your article really stood out to me is that sleep diagnostics have really taken off, particularly when we're thinking about obstructive sleep apnea. And I think we all might sort of scratch our heads and be like, "This is a neurology podcast. Why should I, as a neurologist, care about obstructive sleep apnea?" But I think you laid out a very convincing argument in the article. Walk us through why we should care about this. 
Dr Lee-Iannotti: Absolutely. So, for neurologists, sleep matters, and I hope that my article translates that. Obstructive sleep apnea, which I'm gonna call OSA, is incredibly common in all of our neurologic patients, whether you see epilepsy, Parkinson's, stroke, Alzheimer's, neuromuscular, or even chronic headache patients. The prevalence of sleep apnea is as high as 70% in these patients. 
Dr Albin: Wow. That's incredible. That is an incredibly high number. 
Dr Lee-Iannotti: And if I can add, Dr. Albin, there's growing literature in multiple studies across the literature that show that untreated sleep apnea negatively impacts neurologic outcomes in our patients. So, it is really important to ask the question about sleep, and if the red flags pop up, to then screen for sleep apnea in particular. 
Dr Albin: I think that that's a great point for us to drill down on, and obviously you're a sleep neurologist. You're very used to screening people in the clinic. But say someone comes in, and I'm gonna have you put your former stroke hat on, and say someone comes into the stroke clinic, and you're just making sure that they're optimized on their aspirin or dual antiplatelet therapy, and you're doing secondary risk modification. How would screening for OSA fit into that? 
Dr Lee-Iannotti: It would be a part of that screening process to look at preventative ways to prevent strokes, whether it be primary or secondary prevention. So, we did a survey a while back, and it actually showed that 17% of stroke neurologists are screening for sleep apnea. It has quadrupled, fortunately, in the last few years due to public awareness and a lot of education that the AAN has done, in fact. So, at this point, I would say not asking about sleep apnea to a stroke patient is similar to not asking about diabetes. 
Dr Albin: So, we really have to be cognizant and conscious about saying, you know, "Do you snore at night? Do you have episodes of apnea, or does someone witness you stop?" Are there things that you ask that maybe I wouldn't be aware and thinking of? 
Dr Lee-Iannotti: Those are the right questions, and then very practically, very easy questionnaires to implement that literally take a minute that your nurses or medical assistants can administer to the patient, and the most commonly one that is used in stroke patients is called the STOP BANG, S-T-O-P B-A-N-G, which is a validated questionnaire to screen for symptoms. 
Dr Albin: Absolutely. So okay, so this is easy to do. We should all be doing this. If you're not, now's the time. And I suspect if they screen positive, next steps, it can be hard to get into a sleep lab, and we're gonna talk about some workarounds, but I think some of our listeners may never have spent time in the actual sleep lab. So, let's say you refer a patient and you actually can get them in for a gold standard in-lab sleep study. What's gonna happen in that sleep study? 
Dr Lee-Iannotti: Yeah. And I just want to preface this by saying that my article hopefully highlights that we've come a long way where we understand that there are many neurologic populations then that can undergo home ambulatory sleep studies with just as much accuracy as an in-lab polysomnogram. But with that, I wanna say an in-lab polysomnogram is actually a highly sophisticated physiologic recording overnight, typically, unless somebody is a day sleeper. So, if I could take a minute to kinda describe the data that we're monitoring throughout the night. There is a limited EEG. We concentrate on frontal, central, occipital leads to look at sleep staging. We have eye leads. We have EMG leads on the chin and the leg. We look at EKG, flow monitors, belt, and then we also do pulse oximetry, snoring mics, and even body position sensors. So, a lot is going on. 
Dr Albin: This is incredible. Yeah, it truly is. I mean, this is like... I'm a neurointensivist, and so I think that you have just really outdone what I consider multimodal monitoring in your sleep study patients. I'm not even sure our neuro ICU patients accumulate that much data. All right, so tell me, they go through, and they can get this. But like you said, there's actually a lot of data that you've presented that, you know, not everyone needs to go to the in-lab sleep study. So how do you decide who actually needs to be in a sleep lab versus who can do this at home? And then how do you set them up with getting this done at home? 
Dr Lee-Iannotti: Yeah. The home sleep studies are really more accessible ways for us to assess for sleep apnea in our neurologic patients, especially patients who live in very rural areas and don't have access or have very long wait times for an in-lab polysomnogram. With that being said, though, Dr. Albin, I will say that there are a subset of patients who have to go into the lab, and those are patients where you suspect a sleep disorder other than obstructive sleep apnea, so like parasomnias or central sleep apnea, patients with severe cognitive or physical debilitation, like our stroke patients who are hemiplegic and won't be able to apply the home sleep study. But for the most part, I do feel like a home sleep study is a good beginner study to screen the patient. And if there are red flags, then you can always get the in-lab afterwards. 
Dr Albin: That's super helpful. And just from a pragmatic standpoint, will insurance cover the home sleep study? 
Dr Lee-Iannotti: They will, yes, and it's all about documenting. So, if I could get really practical, for neurologists, it really just requires documenting snoring, for one, whether it's noted by the patient or by their bed partner, and then any form of hypersomnia, which is daytime sleepiness or even a sense of fatigue, having low energy or napping during the day. 
Dr Albin: I suspect so many of our patients meet those criterias. That seems, like, wildly simple to do. 
Dr Lee-Iannotti: Yes. And if you wanna be the favorite referral person to your sleep neurologist or your sleep specialist, then take another step and do that STOP-Bang. And if you record a score greater than three, that automatically gets them at least a home sleep study. 
Dr Albin: It's amazing. And then when you get this data, again, this is really practical, pragmatic stuff, how do you get the report? Does it integrate in your electronic medical record? Does the patient bring it in? How do you get that data back? 
Dr Lee-Iannotti: Yeah, so this is where technology is amazing, Dr. Albin. Now we have disposable devices. Sometimes they sync to the WatchPat, or the greater Wi-Fi. So we can get them all through password-protected internet forums that transmits the data, so sometimes the patients don't even have to come back to give us the data. And then we have different forms where we can actually relay the results as well, either through the electronic medical record or through systems themselves to relay those results directly to the patient. 
Dr Albin: Yeah, and your article really laid out in beautiful tables, like, all the different devices that are available to patients, and it's honestly mind-blowing how many of these companies and devices exist. So, seems like the world is your oyster in terms of picking from them. 
Dr Lee-Iannotti: Absolutely. I think there's... The last time I counted, there was over 20 different home sleep study devices for obstructive sleep apnea. And it's a great thing to have, but sometimes too many choices can be a little bit confusing. So that's where I do say partner with your sleep specialist close by, and they will find the right type of home sleep study device for your particular patient. 
Dr Albin: Drilling down a little further, let's say your patient does get diagnosed with OSA. One of the things that really stuck out to me is that there's a whole range of now devices that are new that make this treatment easy so that we can actually prevent and treat neurological conditions by just improving patient sleep. So, walk us through a little bit about how that landscape has changed. 
Dr Lee-Iannotti: Sure. And I'll start with the gold standard of treatment, which is still CPAP, which is continuous positive airway pressure. Not only can we monitor the pressure, look at adherence, change the humidification for the patient all remotely through, again, password-protected internet forums, but we can even change the pressure with patients 300-plus miles away. 
Dr Albin: Wow. 
Dr Lee-Iannotti: It's really cool, right? It prevents patients, especially with significant neurologic debilitation, from having to come into the office for adjustments. The other thing I wanted to mention, Dr. Albin, is for patients, a lot of patients like positive feedback on a daily basis. And a lot of these companies, if you are on CPAP, have come up with a smartphone app that you can look at how many hours you used your CPAP device. They give you a score, and they even tell you how many times you had stoppage of breathing that night. 
Dr Albin: I think that this is what's really exciting about where we are in neurology and, like, neurologic care, is we have gotten so much better at getting patients their own data and allowing people to really see that data, integrate lifestyle changes, and see how it impacts them. And that positive feedback loop, I think, is a really powerful tool for our patients to say, "Look, this makes me better," or, "Oh, this makes me worse." I'm just really excited by how much data we can give directly to our patients. 
Dr Lee-Iannotti: I agree. It's so empowering. You know, as a CPAP user myself, you want that positive affirmation that all of your efforts at night and cleaning your mask and your machine paid off, and everybody likes to see an A+ on their report card. 
Dr Albin: I love that. Now I'm going to ask you on the flip side, I imagine, and I myself am a sleep tracker, like I have my little device and I look at, you know, the score in the morning and I kind of perseverate on like what makes it better, what makes it worse, and I can imagine that sometimes in sleep clinic, people are coming in to you and they have just pages and pages and, you know, they're flipping through all their data from the last year. And I imagine that's pretty overwhelming when you have just the insane amount of data that these devices can generate. So, from another pragmatic, practical standpoint, how are you integrating all that data when someone comes in for a sleep visit? 
Dr Lee-Iannotti: I love that question. So first of all, I will say myself, and I think a lot of my sleep colleagues, we love objective data, right? Because it's something that we can see. We can see whether it matches their subject's symptoms. Sometimes it can be a lot of reassurance that, "Look, you actually got more sleep than you thought you did." But sometimes patients will bring in like a month's worth, and that's really hard to analyze, you know, in a 30 or 60-minute visit. So oftentimes what I do is I look at like the last week or last two weeks, and I look at trends. And I think a lot of the apps for whatever device you decide to use have done a really good job in terms of visual graphics to show how much sleep on average you're getting, how much deep sleep or REM sleep or wake-up times that you have. So, I, again, I feel like the technology has really helped us consolidate a lot of data, but also be efficient with the messaging that we relay to our patients. 
Dr Albin: Absolutely. And I know personally, at least for the sleep tracker I wear, it also allows you to diary. So, you can say like, "Oh, last night I had a glass of wine," or, "Yesterday I had a really hard workout," or, "I stayed out late with friends," or, "I was on call." Turns out call is really, really bad for my sleep. But it does allow you to sort of track what behaviors, and I wonder how much of that informs what you're counseling patients to do in terms of trying to notice the things that either improve their sleep performance or their subjective feeling of restlessness or restfulness, and how all of that plays into what you're doing in the clinic. 
Dr Lee-Iannotti: I love all of those comments. It is validation for the patient. Again, it's empowering for them to look at, what did I do last night to get more REM sleep than the night prior? I want to mention that the best people who do this so well are professional athletes, and they look at, how am I going to cater my day to make sure that I'm sleeping well, that I reduce my risk of injury and concussion and increase my reaction time? And I feel like all of us should do that. That's such a great philosophy, to analyze how we can do things better. 
Dr Albin: I love that. This whole issue, but this article in particular, really emphasized to me that sleep, again, it's not a passive time that we're taking a nap. It's a really active form of sort of neurologic healing. There's important removal of toxins through the lymphatics. And like there's a lot happening in sleep, and there are so many more tools that allow us to unpack that sort of peak performance of sleep, which again, sort of is that athletic mentality of like, how can I make this better? Not just to treat a neurologic condition, but also really importantly, to prevent one. 
Dr Lee-Iannotti: I often refer to sleep as icing on the cake. With our patients, when you're doing everything right, for example, a multiple sclerosis patient, they're on the right medications, they are exercising, they're participating in rehab, their mood is good, but they're just not getting to the quality-of-life metric that they want to be, it usually is sleep. And if you can add that as a neurologist to your piece of the algorithm to help your patient, it really does improve their quality of life and ultimately their neurologic outcome. I'm a true believer of that. 
Dr Albin: I was a true believer. I've been made even more of a true believer through your article and getting to talk to you. I always like to close by asking the person I'm interviewing, what's one really exciting thing in this field? What are you kind of most looking forward to as you think about sleep medicine and its impact in neurology in the next five or 10 years? 
Dr Lee-Iannotti: Oh, I love that question, too. So, the thing I'm most excited about in the field of sleep, and specifically sleep neurology, is the power of preventative care. When I did a lot of stroke, I would see young people, older people, healthy people, people with a lot of genetic risk factors come in, and one minute they were totally normal. The second minute, they're paralyzed and can't speak. And for a lot of these patients, I would ask, "Why am I seeing you now? Why couldn't I have seen you 10 years earlier, worked on risk factors, and prevented this outcome?" And I truly believe that is exactly where sleep lies. If you work on sleep, whether you're an adolescent, 20 year old, 30, et cetera, you are ultimately going to prevent horrible cardiovascular, cerebrovascular, neurologic diseases in the long run. 
Dr Albin: So important. I really want to direct our listeners back to your article because all of the articles are really practical, but this one in particular looks at how do you do this? What are your options? How do you get this to patients? It really is sort of a step-by-step guidebook on like, A, why this is important, how you should screen, what you should do if someone screens positive for needing to have a sleep study.There's so much more technology that allows really anyone anywhere to have access to the testing that they need to get the right diagnosis, to improve their sleep, to improve their cognitive outcomes, to improve their neurologic health. It's pretty amazing. 
Dr Lee-Iannotti: It is amazing. And in the article, I do allude to certain devices and then websites that are very helpful. If I can announce, Dr. Albin, I'm super excited about this. Through work with the American Academy of Sleep Medicine, endorsement with the AAN, we are coming out with a new clinical guideline specifically on home sleep study devices and looking at the validation studies. So, I think that's going to be very helpful. But I hope that everybody after listening to this picks up the phone, call your friendly sleep specialist, and align with them and partner with them. And this will ultimately help your patients, I guarantee it. 
Dr Albin: Again, today I've been interviewing Dr. Joyce Lee-Iannotti about her article on sleep diagnostics and monitoring technology in obstructive sleep apnea. This article appears in the August 2026 Continuum issue on Neurology of Sleep. Be sure to check out Continuum Audio episodes from this and other issues. And thank you to our listeners, and thank you, Dr. Lee-Iannotti, for joining us today.
Dr Lee-Iannotti: Thank you. 
Dr Monteith: This is Dr. Teshamae Monteith, Associate Editor of Continuum Audio. If you've enjoyed this episode, you'll love the journal, which is full of in-depth and clinically relevant information important for neurology practitioners. Use the link in the episode notes to learn more and subscribe. AAN members, you can get CME for listening to this interview by completing the evaluation at continpub.com/audiocme. Thank you for listening to Continuum Audio.

Obstructive sleep apnea affects approximately one in four adults and is especially common among patients with neurologic disorders, including stroke, Parkinson disease, dementia, epilepsy, and neuromuscular conditions. In this episode, Dr. Stephanie Stahl discusses why neurologists should routinely screen for OSA, highlights key symptoms and risk factors, reviews important considerations when interpreting sleep studies, and outlines current treatment options beyond CPAP. Learn how recognizing and treating sleep apnea can improve quality of life, optimize management of neurologic disease, and reduce long-term health risks.
In this episode, Aaron L. Berkowitz, MD, PhD, FAAN, speaks with Stephanie M. Stahl, MD,
FAASM, author of the article "Obstructive Sleep Apnea" in the Continuum® August 2026 Sleep Neurology issue.
Dr. Berkowitz is a Continuum® Audio interviewer and a professor of neurology in the Department of Neurology at the University of California, San Francisco, in San Francisco, California.
Dr. Stahl is an Associate Professor of Clinical Medicine and Sleep Medicine Fellowship Program Director at Indiana University School of Medicine in Indianapolis, Indiana, where she also serves as Sleep Laboratory Medical Director in the Division of Pulmonary, Critical Care, Sleep, and Occupational Medicine.
Additional Resources
Read the article: Obstructive Sleep Apnea
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Earn CME (available only to AAN members): continpub.com/AudioCME
Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud
More about the American Academy of Neurology: aan.com
Social Media
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@ContinuumAAN
Host: @AaronLBerkowitz
 Full episode transcript available here
Dr Berkowitz: Obstructive sleep apnea is very common. It can cause or contribute to common neurologic symptoms, such as headache and impaired cognition, and it's a risk factor for stroke. And yet, if you're like me, you may not know too much more about sleep apnea than that. Today, I have the pleasure of talking to sleep expert Dr. Stephanie Stahl to learn what every neurologist should know about OSA. 
Dr Jones:  This is Dr. Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. 
Dr Berkowitz: This is Dr. Aaron Berkowitz. Today I'm interviewing Dr. Stephanie Stahl about her article on obstructive sleep apnea. This article appears in the 2026 Continuum issue on Neurology of Sleep. Welcome to the podcast, Dr. Stahl, and could you please introduce yourself to our audience? 
Dr Stahl: Yeah. Thank you for having me. I'm a sleep medicine physician and neurologist and medical director of the Indianapolis Sleep Lab at Indiana University Health. I serve as the director of the Sleep Medicine Fellowship program. I'm faculty advisor for our very first student interest group in sleep medicine at Indiana University School of Medicine. I'm also actively involved in some national leadership roles, including the incoming chair of the American Academy of Sleep Medicine's Education Committee and co-chair of the Academy's Inter-Scorer Reliability Gold Standard Panel. So, I really appreciate this opportunity. I look forward to our discussion. 
Dr Berkowitz: Me too, and we appreciate the opportunity too to get to talk to you. You have so much expertise in this area, and I certainly encourage our listeners to look at your article, which is very comprehensive and up to date, and I learned a ton from it. I didn't get much exposure to sleep neurology as a trainee, and I've always worked in academic centers where we have a sleep group and we can refer patients there. So, I have to admit, sleep may probably be the area of neurology I know the least about, and felt like I was learning something new from pretty much every line of your article, and I know our readers will too. So, your article has a lot of excellent detail for our readers on the diagnosis and treatment of this very common condition. But I'd like to keep our interview relatively high level today and focus on the essentials for the practicing general neurologist. So, to start, can you just give us a sense of what obstructive sleep apnea is, and what every neurologist should know about it? 
Dr Stahl: Yeah. So obstructive sleep apnea is characterized by either partial or full obstructions in the upper airway. That may sound pretty simple, but this leads to a whole bunch of issues. It leads to oxygen desaturations, arousals from sleep, leading to sleep fragmentation. This can then lead to sympathetic nervous system activation, cerebral hypoperfusion, leading to a whole bunch of symptoms or neurologic conditions. 
Dr Berkowitz: Great. And you mentioned this in your article, but just to emphasize, how common is obstructive sleep apnea in the general population? 
Dr Stahl: Yeah. So, about a quarter of the general population have obstructive sleep apnea. Much more common in many neurologic conditions. 
Dr Berkowitz: Yeah, so very common disorder. We are seeing patients with it quite frequently, whether that's the reason they are seeing us in neurology or not. And this leads to my next question, which is what neurologic symptoms or presenting concerns of a patient should make us think about OSA and the differential diagnosis, and what factors based on the history or the exam or the context would make you suspicious for OSA as the cause of a neurologic symptom? In other words, the patient's presenting with classic symptoms of OSA, and that's why they're seeing a neurologist or seeing a primary care doctor, but is coming for evaluation of, say, headache or other symptoms. And what symptoms would make you think of wanting to consider OSA, and then what aspects of the history or otherwise would make you want to evaluate the patient for OSA? 
Dr Stahl: I think a really important takeaway is for neurologists to know that obstructive sleep apnea is very common in neurologic conditions and has that potential to worsen a lot of these conditions or their associated symptoms. And so, it should be on our radar. There are certainly some basic questions and signs and symptoms that we can ask patients about or, or take a look at on exam. And so particular symptoms include snoring. Anybody that snores loudly or frequently, that's a strong risk factor for obstructive sleep apnea. If someone's seeing them stop breathing in their sleep, if they are waking up a lot throughout the night. There are some other symptoms that we may not necessarily attribute upfront to obstructive sleep apnea, such as nocturia, nocturnal reflux, night sweats. There are some daytime symptoms, of course, too, like unrefreshing sleep, daytime sleepiness, morning headaches, an important one in neurology. And then we take a look at the patient's exam. And so, some things that neurologists might want to be thinking about are people with obesity are certainly at a risk for obstructive sleep apnea. But it's also very important to know that someone does not need to have obesity in order to have obstructive sleep apnea. We look at neck size, other morphologic characteristics, such as how much that we can see in the back of their mouth. Can we see their uvula? Does their tongue size appear large in their mouth? And then some other risk factors too, such as male gender, older age, family history, post-menopausal state in women. All that being said, though, sometimes in neurologic conditions, we don't have all of those symptoms or risk factors to be thinking about. And so, in certain neurologic conditions such as stroke where obstructive sleep apnea is very common and has the potential to increase the risk of another stroke, we may need to be thinking about testing these patients even with minimal symptoms or other risk factors. 
Dr Berkowitz: That's very helpful. So, you mentioned their headache might be the presenting symptom, right, to a neurologist, and we should certainly be thinking about obstructive sleep apnea as a potential diagnosis, even the cause of the patient's headache, particularly you said patients with morning headache. I often try to think about in patients presenting with, for memory loss, or other cognitive concerns, and that may be due more to inattention from poor sleep, so asking about sleep and symptoms of sleep apnea in those contexts. Are there any other presenting neurologic symptoms not particularly related to sleep? I'm thinking of headache, memory loss, other symptoms that would make you think, "Oh, I should actually screen this patient for sleep apnea also." 
Dr Stahl: Yeah, other symptoms to think about in pediatrics, hyperactivity, people that have impaired vigilance, as you alluded to, that poor attention. Sometimes people get misdiagnosed with ADHD, and it's actually just a manifestation of obstructive sleep apnea. 
Dr Berkowitz: You alluded to this, Dr. Stahl, that stroke, for example, patients are at higher risk of developing sleep apnea as a result of stroke, and it's also a risk factor for stroke. What other neurologic conditions, primary neurologic diseases, put patients at a higher risk of OSA? And again, similar to the last question I asked you, what are some clues that we should evaluate for? We might be following a patient for their post-stroke care over time and not necessarily thinking about diagnosing a separate condition in them since we're following them for their stroke or their degenerative disease. What are the conditions that put patients at a higher risk of OSA as a result of the condition, and then when would you think about screening them for it? 
Dr Stahl: Some particular neurologic conditions where obstructive sleep apnea are very common, in addition to stroke and, and TIA, include Parkinson disease. It can worsen a lot of the motor, cognitive symptoms, sleep disruption that we can see in Parkinson disease. Very common in all causes of dementia, but in particular Alzheimer disease and Lewy body dementia. Very common in neuromuscular conditions. We should definitely have obstructive sleep apnea and all forms of sleep-disordered breathing high on our radar. In conditions like myotonic dystrophy. Charcot-Marie-Tooth is another one where obstructive sleep apnea is very common. Myasthenia gravis, it can worsen the symptoms of that. In particular, a pearl is if somebody has morning weakness in myasthenia gravis, obstructive sleep apnea should be high on your radar. And also, as you mentioned, any forms of headaches. There are some other things too. If somebody has poor seizure control, especially nocturnal seizures, you might have obstructive sleep apnea on your radar as well. 
Dr Berkowitz: So, I think you've covered essentially every category of neurologic disease, right? We have cerebrovascular, movement, neurodegenerative, neuromuscular, epilepsy, all conditions where either the disorder itself, such as stroke or the, correct me if I'm wrong, the neurodegenerative disease puts the patient at risk. Or the patient may be at risk for exacerbations of their disease, as you mentioned in myasthenia. I love that pearl. Not fatiguable at the end of the day, but if the patient with myasthenia is telling you they're feeling weaker at the beginning of the day, then think about obstructive sleep apnea and that obstructive sleep apnea worsening control of epilepsy due to poor sleep. So really a lot of bidirectional interactions with this common condition. Okay, so if we're concerned about obstructive sleep apnea, again, myself, a general neurologist speaking perhaps on behalf of other general neurologists, we see a patient with headache or reporting memory loss that we find to be impaired attention, or we see exacerbation of their underlying primary neurologic disease. As you mentioned, we think, "Oh, I've listened to this podcast. I've read Dr. Stahl's article. I should probably be thinking about OSA in this patient, and I should order a sleep study." Now, I admit when I get the sleep study back, I scroll to the bottom, I see they do have obstructive sleep apnea, I'm going to send them over to a sleep specialist. But for the general neurologist, what are some high-yield pearls and some pitfalls to be aware of when we get sleep studies for obstructive sleep apnea, and we are looking at the results?
Dr Stahl: The first thing is to understand that there are two main types of sleep studies: in-lab polysomnography and home sleep apnea test. In-lab studies are typically what we consider the more accurate type of study. Main reason for that is that we have EEG, so we can see if someone is awake versus asleep. Most home sleep apnea tests do not utilize EEG, and so when we're looking at respiratory events, apneas or hypopneas, we're looking at over the total recording time rather than the total sleep time. So, we know we're going to capture some time where a person is awake, where we don't have sleep apnea events, and that can be a big amount of time in people with insomnia, poor sleep efficiency. And as a result of that, it can lead to an underestimation of the apnea-hypopnea index. That's really important for people to understand that that means we can end up with a false negative home sleep apnea test, or it can put them in a category of lower severity than what they actually have. And so, if you get a home sleep study report back that's negative for sleep apnea and you remain concerned, you need to go on to do an in-lab study, where about twenty to fifty percent of people will go on to have a positive in-lab study. You can also get false positives with home sleep apnea tests too, and so ideally, we should only be doing home sleep apnea tests in people that are at high risk of having obstructive sleep apnea to decrease our chance of false positive study. When we get that sleep study report, what's important to take a look at? So the main number that we look at currently is the apnea-hypopnea index. The number of apneas, which are full obstructions in that upper airway, or hypopneas, partial obstructions in the upper airway where either there's an oxygen desaturation or an arousal associated with that. Less than five is considered to be normal. Anything five or more gives them a diagnosis of obstructive sleep apnea, and then we stratify them based on the AHI. But it's important to take a look at more than just the apnea-hypopnea index. And while my eyes too on various reports like echocardiograms want to jump to the impression, it is important to take a look at that full report, see what their oxygen levels averaged and what they dipped down to. The arousal index, which is how many times a patient may have woken up briefly throughout the night. Take a look at the histogram, usually an image at the bottom of their report that shows what sleep fragmentation may have been like so that you can take that all in and make that decision. How important are these study findings, and is this a person that would benefit from treatment? 
Dr Berkowitz: That's a fantastic overview of sleep studies and some of the highlights to look out for, even if we won't be understanding every detail as you would to know most importantly the caveats about home sleep testing having a fairly high percentage of false negative and false positive results. So being wary if our suspicion is high, and that test is normal or inconclusive to get an in-lab sleep study. And if our suspicion is low or maybe we haven't ordered the test and the patient has had it done elsewhere, and the history doesn't really match up to know that there are false positives on the home studies as well, and again, an in-lab study to settle the diagnosis. Is that right? 
Dr Stahl: Yes. 
Dr Berkowitz: Okay. Now, for most neurologists, probably if we diagnose OSA, we will be referring the patient to a sleep specialist like yourself for treatment. I think we're all familiar with CPAP and patients being on CPAP. Your article mentions a number of treatment modalities I admit I have not heard of before or maybe heard of in passing, acknowledging most general neurologists are not going to be prescribing or knowing with the nuance that you do as an expert how to decide which treatment a patient would most benefit from or most qualify for. So, can you just give us a broad overview, again, for the general neurologist acknowledging we might see a patient whose past medical history says OSA being treated with fill in the blank. What are the different treatment modalities, and how do you think, just so we can learn from you in broad brush strokes, about particular treatments for particular patients? 
Dr Stahl: As you mentioned, most people are familiar with positive airway pressure or PAP therapy, and that does remain our most efficacious treatment. The way I explain it to patients is why PAP therapy is the most effective treatment is it's the only treatment that can take all of the tissues of that upper airway and open them up. Whereas all of our other treatments, we're going to target smaller spaces of that upper airway. So, our first option is if we can get somebody on PAP therapy, we know that that's going to be the best option for the majority. PAP therapy works by basically acting as an air splint to open up the air tissues. Know that masks are not interchangeable. There are masks that cover the nose and go over the nose and mouth and under the nose. Full face masks that cover the nose and mouth, they do typically require higher pressures, also tend to be less comfortable for a lot of patients as well. In addition to different PAP masks, there's different modalities of positive airway pressure therapy too. There are machines that auto-adjust, some that provide fixed pressure, bi-level PAP that provides a higher inspiratory pressure, lower expiratory pressure. Then outside of PAP therapy, there are, as you alluded to, a lot of options and more, continuing to come down the pipeline as well. Mandibular advancement devices or a form of oral appliances has been around for a while. This is device that somebody wears in their mouth. It's preferably customized for their teeth and titratable, meaning that they can make adjustments that pulls their mandible forward in relation to the maxilla in order to pull those tongue tissues further away from the back of the upper airway. That's ideally managed by a qualified sleep dentist or someone that specializes in oral appliance management. Other treatments include surgical options, including hypoglossal nerve stimulation, which is an implanted device that causes the tongue to protrude repetitively throughout their sleep period to hopefully open up the airspace. There's some other surgical options too that open up various places of the upper airway. There's a daytime treatment of obstructive sleep apnea, transoral neuromuscular electrical stimulation that changes the muscle fiber type of the tongue. And then there's some adjunctive treatments that can be helpful too, such as positional therapy, oral facial myofunctional therapy that helps a person breathe better through their nose and may help train the upper airway muscles. 
Dr Berkowitz: Great. Well, that's a very helpful overview, and again, I refer our listeners to your article, which talks about all of those modalities in very comprehensive detail. So, Dr. Stahl, as we wrap up our conversation, you have a captive audience of neurologists and neurology trainees here. What would you like to leave us with that every neurologist should know about obstructive sleep apnea? 
Dr Stahl: The most important, again, is for neurologists to know that obstructive sleep apnea is so common in your patient population, and it can have a significant negative impact on quality of life and health, including many neurologic conditions. And at the same time, obstructive sleep apnea is very treatable. We have so many options nowadays that we can usually get someone onto adequate treatment. And treatment has that potential to improve several neurologic symptoms and disorders, even at times when you don't think that there's an opportunity to improve symptoms such as say in, headache. So, neurologists really should be screening for signs and symptoms of obstructive sleep apnea, as well as considering testing in high-risk, potentially asymptomatic or minimally symptomatic patients. 
Dr Berkowitz: That's a fantastic overview of some of the many pearls that you shared with us today, as well as in your article. So, thank you so much again. Today, I've been interviewing Dr. Stephanie Stahl about her article on obstructive sleep apnea. This article appears in the August 2026 Continuum issue on neurology of sleep. Be sure to check out Continuum Audio episodes from this and other issues. And thank you so much to our listeners for joining today, and thank you again, Dr. Stahl. 
Dr Stahl: Thank you again for having me. 
Dr Monteith: This is Dr. Teshamae Monteith, Associate Editor of Continuum Audio. If you've enjoyed this episode, you'll love the journal, which is full of in-depth and clinically relevant information important for neurology practitioners. Use the link in the episode notes to learn more and subscribe. AAN members, you can get CME for listening to this interview by completing the evaluation at continpub.com/audioCME. Thank you for listening to Continuum Audio.