The Mystery of Idiopathic Hypersomnia: Symptoms, Diagnosis, and Hope for the Sleepy

[00:00:00] So idiopathic hypersomnia, we should think of it this way. These are extremely sleepy people. They have what we call sleep inertia, which is sometimes also called as sleep drunkenness, meaning I wake up as if I'm drunk or I'm super groggy and it takes me forever to get going in the morning. These patients are snoozing alarm after alarm and they have multiple alarms. They have family members reaching out to them to wake them up.

[00:00:28] It's taking them 30 minutes, an hour or even longer to feel like they're fully there as far as their cognition is concerned. It is so sneaky and the symptoms are so weak. Plus, there are so many other symptoms that I would rather blame more common conditions. Unless you take a very holistic view of a patient and go back and look at the whole history, it can very easily be missed.

[00:01:12] Welcome back to The Hidden Sleep Disorders Show, where we uncover the science, diagnosis and treatment of sleep disorders that often hide behind chronic fatigue, poor sleep and unexplained exhaustion. Today, we're going to take a closer look at a condition that many people have never heard of, even though it may be affecting far more people than we realize, idiopathic hypersomnia. So if you've ever felt like you could sleep for 12 hours and still wake up exhausted, or if you've been told that your labs are normal, but you know something just isn't right, this episode may finally give you some answers to what you've ever felt.

[00:01:41] And the clarity you've been looking for. So it's always a pleasure to see you, Dr. Sani. How are you? I'm excited to have this conversation. I know that we've talked about this, but I feel like I'm probably going to benefit from this episode a lot. But nice to see you again.

[00:01:55] Nice to see you, Leila. I'm doing great. And, you know, I want to dedicate this episode to all the high performers of this world. You know, I used to think that especially idiopathic hypersomnia, that it would somehow derail a person's career trajectory, or make them not be as successful. But I've been proven wrong and wrong again.

[00:02:19] And I see a lot of high performers who struggle with this, but somehow they've been able to tackle this problem and come out at the top. So this one is dedicated to all those high performers. Awesome. And speaking about that, like you just touched on with high performers, I think that this is particularly common with high performers, right? But it could have kind of affects everyone. Is that right?

[00:02:43] That's true. Yeah, there is no rhyme or reason. In fact, the name itself tells you that idiopathic literally means I don't really know. And hypersomnia is so I don't really know why you're sleeping. So it is an exclusion disease where I have to rule out pretty much everything else before I can label somebody with idiopathic hypersomnia.

[00:03:08] So the name itself suggests. Now, having said that, you know, it has pretty distinct diagnostic criteria, which is sort of paradoxical for a disease condition we're calling idiopathic. But the reason we're calling it idiopathic is because we don't really have a good understanding of the pathology behind it as to what is triggering this problem.

[00:03:32] But we have identified the problem really well. And we've gotten pretty good at recording and making the diagnostic criteria relevant for this condition. Absolutely. And speaking about it, the term idiopathic hypersomnia, most people haven't really heard about it from their doctor. And you just touched on it. But is there anything that you didn't say in terms of what it is exactly or maybe how you would explain it to someone who's just hearing about it for the very first time?

[00:04:00] That's right. So idiopathic hypersomnia, we should think of it this way. These are extremely sleepy people, just like you would think of narcolepsy. And the only difference is when we do the sleep study, it shows certain features that are not narcolepsy. So excessive daytime sleepiness is the main feature that's present in all these patients.

[00:04:29] And these used to be a few years ago that we would break it down into that, hey, are you a long sleeper? Meaning you could potentially sleep 11 plus hours in a day and still wake up feeling unrefreshed. Or you could sleep all night long. You're still sleepy during the daytime and you would take long naps during the daytime and you wake up feeling even more groggy or even worse from those naps.

[00:04:58] And then you're questioning yourself, OK, why the heck am I even sleeping so much if it's not really helping me, if it's not restoring my tiredness or sleepiness? So that's really one of the main feature. There are other features that we'll go over as we go on in the show. I think a lot of people feel tired all the time and they wonder if they're just someone who really needs more sleep than the average person.

[00:05:24] But how do you distinguish between someone that feels like that or idiopathic hypersomnia from someone who may naturally just want to sleep longer and have a longer sleep need? That's right. And in sleep medicine, we call these long sleepers really long sleepers.

[00:05:41] But they're a normal variant, right? On a scale where we're looking at the hours that a person sleeps, we have short sleepers that only need five, six hours of sleep and they're good to go. We have then the normal ranges where most of us need anywhere between seven to eight and a half hours of sleep and we feel great after that. And then the long sleepers who need nine, ten hours of sleep and sometimes even more.

[00:06:09] But once they get that amount of sleep, they feel great. They can go about their business. Now, in contrast, these idiopathic hypersomnia patients, they could sleep however much they want. They never feel refreshed. They're never feeling that the burden of sleepiness ever lifted off from their shoulders.

[00:06:31] The other feature that's very common and that sort of helps me think about or suspect idiopathic hypersomnia is that they have what we call sleep inertia, which is sometimes also called as sleep drunkenness, meaning I wake up as if I'm drunk or I'm super groggy and it takes me forever to get going in the morning.

[00:06:56] In fact, that's one of the questions that I ask for a follow-up is that, hey, how long does it take for you to get going in the morning? And I'm always surprised by the answer. So it's not like I'm springing out of the bed and ready to take on the world. These patients are snoozing alarm after alarm and they have multiple alarms. They have family members reaching out to them to wake them up.

[00:07:21] And it's taking them 30 minutes or even longer to feel like they're fully there as far as their cognition is concerned. So that's another big feature that helps me distinguish between a normal long sleeper versus someone who might be dealing with what we call pathological sleepiness, which is idiopathic hypersomnia. And that's so interesting, too, because for someone that is struggling with that, that's their norm.

[00:07:48] They don't even probably realize that that's. That is so true. And it's amazing how much we can just accept. And the other challenge is these conditions start generally somewhere between the ages of 16 and 21 for majority of the folks. And then it makes it hard because there's so many other changes happening in my life, right? I'm growing up. I'm moving out to college. And then my lifestyle is shifting.

[00:08:18] So a lot of these other things get blamed for your symptoms without realizing that, hey, this might be more of a disease condition that I might be dealing with. Luckily, though, not 100% of these patients will have to suffer for all of their lives. There is some remission rate, meaning there are some people who would just get better over time over a period of 5 to 10 years.

[00:08:47] But generally, that remission rate is maybe only 20 to 30%. So whatever remains after that, which is a huge chunk of people, they will struggle with this condition for a long, long time as time goes on. Absolutely. And I think most people also assume that sleeping too much is probably the main symptom. But there seems to be more to it than that, right? So what are some of the most common symptoms that patients really experience?

[00:09:15] And which ones do you think really tend to surprise people the most? That's a great question. And other than excessive sleepiness and the sleep drunkenness or sleep inertia that we mentioned previously, there is another set of features that's hidden in this patient group.

[00:09:33] And these are what we call autonomic nervous system imbalance, which is that these patients might be suffering from conditions like balance problems, where it's like for some reason my balance is always off when I wake up in the morning or during the night even, or even throughout the day. Some of them complain of morning headaches.

[00:09:57] And then headache being such a common condition, I don't think anyone even consider that excessive sleepiness or a condition like idiopathic hypersomnia could be part of the headaches that I'm dealing with in the morning. But that's because of the autonomic nervous system balance. And then some of these patients will have where their heart is racing and causing what we call tachycardia, meaning fast heart rate.

[00:10:24] Or sometimes it's slowing down inappropriately, which is called bradycardia. And so these patients are going to see the cardiologist. They're doing all kinds of heart testing on these. And some of these patients I've seen in practice, they have what we call POTS or postural orthostatic syndrome, where their blood pressure drops in relationship to what position they're in.

[00:10:49] For example, if I go from laying down position to standing up, my blood pressure drops like crazy and I'm feeling dizzy or I'm feeling off balance or my heart is starting to race and I'm having palpitations and stuff like that. So there are all kinds of autonomic nervous system symptoms that show up in this population. Unless you're clearly asking for these or looking for these, you can easily just keep on blaming your heart condition

[00:11:16] or, you know, looking in a completely different direction versus the disease could be just hiding underneath all this. So those are some of the more common symptoms that are very relevant to my idiopathic hypersomnia patients. And I think with sleep disorders, and we talked a little bit about this last time, narcolepsy, I feel like, is the one that's most commonly known or talked about. And like I said, we talked about that a little bit in our last episode.

[00:11:42] And narcolepsy, obviously, involves excessive daytime sleepiness. So how is that different from idiopathic hypersomnia? And why do you think it's important for that distinction with patients? That's a great question, Layla. The narcolepsy type 1 especially. It's much easier to distinguish from idiopathic hypersomnia. Because the type 1 comes with cataplexy, which we discuss how your muscles feel weak in response to some emotion,

[00:12:11] for example, laughter or stress or anger. And my muscles are weak. So if cataplexy is present, it generally makes a clinician's life pretty easy. Then, hey, I'm dealing with narcolepsy type 1. The distinction gets much, much, much harder between narcolepsy type 2 and idiopathic hypersomnia. Because in some cases, the only difference that you can see between those two groups

[00:12:38] is only on the NAP study that we touched upon in our previous episode, is that during the NAP study for a narcolepsy patient, we notice that their brain enters into REM sleep very, very quickly. But that's not the case in idiopathic hypersomnia. So that's what really helps me distinguish between those two based on that sleep study. But clinically, sometimes they could look exactly the same.

[00:13:08] Beyond that, too, many patients, like we've talked about, especially with this condition, can go for years without a correct diagnosis. And I think it's also something that isn't talked about a lot or well known of. So why does idiopathic hypersomnia go undiagnosed for such a long time? Or like you said, maybe mistaken for something else completely? Yes. And, you know, this goes back to our discussion where it is so sneaky and the symptoms are so vague.

[00:13:36] Plus, there are so many other symptoms that I would rather blame more common conditions, right? People have more heart issues. People will have more psychiatric problems. So those are the ones who are going to get addressed first. And that, you know, takes time. So sometimes, even if you have a suspicion of idiopathic hypersomnia, you're still required almost to make sure you're not missing any metabolic disorders,

[00:14:06] for example, low thyroid hormones. Or you're not missing any psychiatric disorders like major depression. Or you're not missing any cardiac issues like autonomic nervous system imbalance I was talking about, like POTS and whatnot. So it becomes extremely challenging that unless you take a very holistic view of a patient and go back and look at the whole history, it can very easily be missed.

[00:14:32] So that's one of the reasons why it takes forever to diagnose someone with this. And even though it has pretty set diagnostic criteria, but I have to rule out sleep apneas. I have to rule out insufficient sleep being a big one in our society because we're consuming so much of the media. We're not really giving ourselves enough chance to have enough sleep.

[00:14:57] And that makes it really hard to get to the point where, hey, because the water is so muddy, it takes a while to start seeing things clearly. And touching on what you're saying now, it's so common that the symptoms are overlapping with other health issues, like some of the ones you mentioned. So what conditions is idiopathic hypersomnia most commonly mistaken for? Because I know they overlap with certain things, but what do you think it's most commonly mistaken for?

[00:15:25] And what does that mean for people who are living with it undiagnosed? So a few different ones. First, I'll start with the ones where we diagnose. And sometimes we have patients who we consider narcolepsy, which is a big one, because there is a massive overlap between those two. The second most common one is if you have residual sleepiness from obstructive sleep apnea. So there are plenty of patients who have obstructive sleep apnea.

[00:15:52] And even after they treat their sleep apnea, their sleepiness never goes away, which is a bummer for them because a lot of us are expecting that, hey, as soon as I treat my sleep apnea, I should see a lot more energy. I should see a lot more wakefulness. But that never really pans out for this subgroup. So that's another group. Third is people who have psychiatric conditions that are messing up or complicating the picture.

[00:16:19] The fourth big group is the people who have medications that could be contributing to excessive sleepiness. And there are all kinds of medications. In fact, if you look at pretty much every medication, if you read the fine print, somewhere it will be causing either insomnia or excessive sleepiness. And that makes it super challenging as well. So those are the main categories that are competing against this diagnosis.

[00:16:46] And that's so interesting, too, because the side effects, like you mentioned, of the medication are complete opposites. So it's really hard, I'm sure, to gauge that. That's right. And sometimes we have to even ask our patients or remove the medication to see if we notice an impact on their day. And sometimes we don't. In fact, one of the requirements or prerequisites for the NAP study is to take people off of their antidepressants

[00:17:15] for a certain amount of time so that it could clear up their system. And that is to ensure that we're getting the relevant data and the medication effect is being reduced to minimum. And so when someone finally does get to a sleep specialist and is being evaluated for specifically idiopathic hypersomnia, what does the diagnostic process typically look like? And what tests or evaluations really help to confirm the diagnosis?

[00:17:42] So the typical journey looks very similar for all these hypersomnia conditions like narcolepsy and idiopathic hypersomnia. Idiopathic hypersomnia, more specifically, I have to rule out and make sure there is no other sleep disorder that could explain some of these symptoms. So my first job is to make sure there is no sleep apnea.

[00:18:05] And if there is, then I want to get that under control completely before moving on to more testing for excessive sleepiness. Then I have to rule out any other metabolic conditions that could be contributing. Any medications. For example, a lot of patients who have chronic pain syndromes for whatever reason, chronic arthritis or some sort of previous injury and or if they had any trauma or accident that could cause hypersomnia too in the past.

[00:18:35] So those things have to be ruled out and make sure that they're being appropriately treated. And after that only, you go about doing the testing. So testing will be done in multiple sort of phases, if you will. The first phase where you're doing some basic testing, for example, a home sleep test to rule out sleep apnea, that could also ensure that I'm not dealing with insufficient sleep.

[00:19:01] For example, hey, if I'm dealing with a person who has poor sleep hygiene or poor sleep sort of timings where they're, you know, all over the place and not really maintaining a good sleep schedule, then we'll probably work on those things before we move on to the next steps. And then once you clear all that, then the next step is to do the nap study with an overnight sleep study to look at their sleep structure at nighttime.

[00:19:30] And then during the daytime, we do this nap study where we have you come in and take multiple naps where we're recording how quickly that brain is falling asleep and for the presence or absence of any REM sleep during those nap episodes. Now, where it gets different from narcolepsy is that not always MSLT and the sleep study, the nap study will yield the results that we are looking for.

[00:19:58] And that is also something we have to consider that sometimes if I get a negative nap study, but I have a very sleepy person in front of me, then there are other ways to approach it. And one of those ways is to do what we call a seven-day or seven-night actigraphy, which is we're monitoring. It's just like Apple Watch is tracking our sleep. So these are medical-grade devices available as well.

[00:20:26] And so those devices, basically, we have you track your sleep pattern or sleep cycles for both day and night for almost a week. And what we're trying to figure out is, hey, is this person averaging more than 660 minutes of sleep in a 24-hour cycle, which amounts to 11 hours of sleep in a 24-hour cycle? Now, it doesn't have to be 11 hours all at once.

[00:20:54] It could be eight, nine hours, and then another two, three hours of nap or even multiple naps. So it's over a 24-hour phase that we're trying to record. In U.S., the third test that I was going to mention, we don't really do that a whole lot because of the coverage problems from insurance. But in certain labs, especially in research studies, we could do what we call a 24-hour in-lab sleep study or PSG.

[00:21:22] And that is to track you for the whole extent of 24 hours to see when you're sleeping, how much you're sleeping. So it basically gives us a lot of freedom to, one, mimic the same sort of sleep schedule that you would at home. Plus, it allows us to see how the sleepiness behaves, how it pans out throughout the whole day and gives us a pretty good snapshot.

[00:21:52] But again, the criteria still is that, hey, I need to have more than 11 hours of sleep show up on that test for me to qualify for idiopathic hypersomnia diagnosis. Now, unlike narcolepsy, there is no spinal tap. There is no genetic test available, at least not in 2026, that we could run. And that's where the challenge is because we don't really have the clear understanding

[00:22:22] of the pathology behind it or pathophysiology behind it. So we have to rely on these indirect markers to figure this out. And that's what makes it probably the most challenging hidden sleep disorder that I deal with. Absolutely. And then once you have come to the conclusion and have this diagnosis for a patient, what kind of treatments or management strategies are available currently?

[00:22:47] And how much relief can patients actually realistically expect once they're on the treatment? So the treatment options are very similar to narcolepsy. And luckily, there is plenty of stuff now available. Because previously, if you go back 10, 20 years ago, all we could do is put people on stimulants like Adderall or Ritalin that we use for ADHD and some other conditions. But they come with their own side effects.

[00:23:15] Plus, they can tackle excessive sleepiness a little bit, but they don't really tackle all these other symptoms of sleep inertia, of autonomic nervous system imbalance, poor cognition, memory issues, headaches. All those things are then often left untreated, or there's a lot more to be desired by the patients to get to a decent level as far as their daytime functioning goes.

[00:23:44] But there are newer medications out there. In fact, only FDA-approved medication currently for idiopathic hypersomnia is Zywave, which is a liquid medication that you take at nighttime to make you sleep harder. And then magically, it helps you feel more alert and awake during the daytime. It also helps reduce my sleep inertia. But the challenge there is not everyone is going to respond to that medication.

[00:24:12] So even if I have the same diagnosis, and if I have 10 people with idiopathic hypersomnia, and I tried Zywave on each one of them, that doesn't mean everyone will respond to that. So some of them will respond and some will not. And the ones who do not respond, then we have to either add on some other medications to manage their daytime functioning, depending on how troublesome it is.

[00:24:38] And then, of course, there is always some new research happening too in this field that we can cover later. Also imagine, with that being said, and going back to what you said earlier about them taking other medications, maybe that can potentially counteract almost. Absolutely, absolutely. Yes, and sometimes we see that where, hey, I'm taking the insomnia medication to help me sleep. On top of that, I have chronic pain condition, and I'm taking pain medications or pain pills to help deal with my pain.

[00:25:07] I have heart problems that I'm dealing with, or I have cholesterol medications that could do it. I have mood disorders, or I have bipolar mood disorder. I'm taking antipsychotic that make people extremely sleepy. So yes, then sometimes we have to what we call deprescribe, where we're trying to take away some of the medications and see if we can make a meaningful impact in their wakefulness during the daytime. And then speaking about medications, let's go beyond that.

[00:25:37] So beyond medications and clinical treatment, what about lifestyle? What about certain lifestyle strategies or accommodations that can really help people with this diagnosis and how they can really manage their symptoms, but maintain a good quality of life? So the biggest one would be to prioritize sleep. If you are dealing with insufficient sleep, this will be impossible to manage if I have idiopathic hypersomnia.

[00:26:04] And even despite managing amounts of sleep or not being sleep-deprived, these patients are still going to deal with a massive burden of excessive sleepiness. But that's going to be worse, five-folds, ten-folds, even worse, if I don't manage my sleep schedule, if I do not prioritize that, hey, if, for example, if I need 10 to 12 hours and I sign up for three different projects and I just have no time to sleep,

[00:26:33] it'll make it impossible to, one, finish those projects in a meaningful way because you're so sleepy and tired, you can't really focus. So I think the best approach would be to make sure you're not fighting this condition with insufficient sleep on your side. So you have to have plenty of sleep, time for plenty of sleep. Now, obviously, real life, it's easier said than done. I could be a single mom working two jobs just to raise my child.

[00:27:02] I could be a dad doing multiple jobs to keep my family, especially how current environment is with the prices keeps going up. So all those things are going to impact, you know, the solutions that go around it. Obviously, if you are taking multiple medications, so you have to look at those and, you know, ask yourself, hey, is this all these five antidepressants that I'm taking,

[00:27:30] are they really making any meaningful difference in my life or are these driving me more sleepy? So those are some honest discussions that patients need to have with themselves first and then with their prescribers next to see, okay, if it's not really working, why do you keep prescribing this to me again and again? So those are some of the things or approaches that we need to have. Absolutely. And we touched on this a little bit too, but sleep medicine is something that's constantly evolving.

[00:27:59] And with this specific diagnosis or idiopathic hypersomnia, it's really only recently just received its first FDA approved treatment. So what about new research or emerging developments? Is there anything that you know of that's maybe coming up or any developments that give you hope for the future care for patients with this specific condition? Absolutely. And there is. There are the same orexin molecules that we are testing in our narcolepsy patients.

[00:28:28] We are also testing those in our idiopathic hypersomnia patients. And the initial reports are quite encouraging. And obviously nothing works 100% for everybody, but there are certain idiopathic hypersomnia patients that we're finding are responding to these newer agents or newer medications. So that brings me hope. But really what I'm trying to achieve from this is that,

[00:28:55] hey, we need to create more awareness because there is still so much left to be discovered about this condition, about this disease. So unless we have more clear understanding on the genetics, on the pathway as to why it's happening, it will be very challenging to come up with some concrete solutions as far as medications are concerned to really tackle this problem. So it truly is one of the hidden sleep disorders and super challenging to deal with

[00:29:24] as a patient and as a physician who would be dealing with that. Absolutely. And before we wrap up this episode, are there any other final thoughts or anything that you want to add on regarding this? So I would like to say idiopathic hypersomnia, sometimes it's a double whammy because one, you are so tired, you're so sleepy, you want the answer right away, but the disease itself is so challenging. And sometimes patients questions like,

[00:29:53] okay, I keep going one test after the other, and you're ordering these multiple sleep studies. But that is to ensure that we're arriving at that diagnosis properly. So sometimes I feel like it requires way more patients on our patient's behalf and on our clinician's behalf to not give up and keep really looking for it if it is a possibility or if it is a clinical suspicion based on the presentation of the symptoms.

[00:30:21] So I think it's easy to just do one sleep study and say, oh, you don't have sleep apnea, go home. Nothing else we could do about it, which is not true. So there are ways to look for it clinically with discussions, with history, with examination, ruling out other medical conditions that could mimic this condition. And then of course, there are some sleep testing, which is available in this day and age to help find out

[00:30:50] or discover this hidden sleep disorder. Absolutely. And it sounds like it's definitely a sleep disorder that affects far more people than most people even really realize. And one that far too often goes undiagnosed for years while patients are being told maybe nothing is wrong or thinking it's something else. So for anyone listening, if you've been living with this unexplained exhaustion, sleeping long hours without feeling fully rested or struggling to wake up in the morning, no matter how much sleep you get,

[00:31:19] this episode was for you specifically. And understanding that a condition like this does exist and that it can be diagnosed and treated is really just the first step towards getting the help that you deserve. So if you found this conversation helpful, make sure that you follow this show so you don't miss any future episodes. Thank you so much. It was another great conversation. I know it definitely makes me think so much more about my own sleep hygiene, just my overall sleep health as a whole. So everyone listening, make sure that you are following and sharing.

[00:31:48] And thank you so much for listening to the Hidden Sleep Disorders show. Dr. Sani, it's amazing to talk to you as always. And I can't wait for our next conversation. Glad to do that. Thank you.