Frustrated With Ih Diagnosis

19 posts in this topic

I'm new here, though I've been reading the forums for a few weeks. I am frustrated with my doctor who diagnosed me with idiopathic hypersomnia and would like to present my scenario to all of you.


I'm 27 years old, and have been experiencing daytime sleepiness regularly since I was 16 or 17, and have been napping daily since I was 19 or 20. I never really thought much of this until the past couple of years since I left university and have a desk job. I always thought I was a good sleeper because I fall asleep almost instantly and can take short, refreshing naps almost anywhere.


However, in the past couple of years, I've started needing 2 - 4 naps a day instead of just one or two and I've started falling asleep involuntarily at work and in other situations. I've also experienced the need to sleep rather than just a desire in the past couple of years. I've pulled over on the bike path for a nap, for instance, to prevent myself from falling asleep while riding.


Since I was a teenager, I have been experiencing sleep paralysis and hypnagogic/hypnopompic hallucinations regularly (perhaps SP between 1 and 3 times a week and HH once a month). I had assumed this happens to everyone, but have since learned this isn't the case. I also occasionally have what I'll call "night terrors" where I hop out of bed terrified about something and need to be consoled before going back to sleep. In about half of these night terrors I have only a vague recollection of that happening (in the other half I end up waking up all the way and remember the aftermath clearly).


With all of this in mind, I was referred last year to a doctor who knows about sleep disorders who then referred me to the sleep centre. I had a PSG/MSLT last week.


During the appointment with the first doctor, he asked me about cataplexy. I'm not sure if I have it, but I described how I always sit in the bench seats of booths at pubs so when I'm laughing with my friends I don't fall over when my head gets heavy. I experiencing the feeling of my jaw being heavy in some situations, particularly when I'm having sex/have an orgasm. I'm generally clumsy in social situations, particularly if I'm caught by surprise (e.g. running into a friend unexpectedly). I also had one dramatic experience of laughing that lead to me lying on the floor, unable to move until I stopped laughing (some of my muscles were still contracting involuntarily, but I couldn't move anything voluntarily except for my eyes). He seemed to think some of that might be cataplexy, might not, but was willing to investigate for narcolepsy so he sent me to the sleep centre.


The second doctor I saw was at the sleep centre. She told me I am "too thin to be a narcoleptic" when I first saw her (I am on the slim side of average), but ordered the PSG/MSLT anyway with some reluctance. I reviewed the results with her last week. I did not receive a copy of the results, but will repeat what I can remember:



Sleep latency: 5 minutes

REM onset: 260 minutes

PLM: 16/hour

Lower than usual percentage of REM (can't remember the distribution of the different stages of sleep)

No significant breathing events



Sleep latencies in each nap:

1: 1.0 minutes

2: 3.5 minutes

3: 3.5  minutes

4: 1.0 minutes

5: 11.9 minutes

Average: 4.2 minutes

No SOREMs observed


I was feeling pretty stressed out during the entire test. During the PSG, I was extremely itchy from the electrodes, etc. which made led me to ask the tech for suggestions on getting back to sleep after I went to the washroom. Apparently I'd been sleeping on and off during the time I thought I was awake. For the last nap on the MSLT I had lost track of the time and had run in from sitting in very bright sunlight only seconds before they plugged me into the machines and told me to go to sleep, which I think explains the longer sleep time for nap 5. I do recall dreaming during both the PSG and MSLT, including one dream in the MSLT that woke me up.


Because no SOREMs were observed and because of the long REM onset during the overnight, my doctor diagnosed me with idiopathic hypersomnia. I was surprised, particularly given that my understanding of "idiopathic" was that extensive testing would need to be done to determine there is no known cause. I didn't realize this is a diagnosis unto itself with a specific set of symptoms.


In any case, once I got home, I googled IH and found that it doesn't seem to describe me at all. I have a regular sleep time at night (7-7.5 hours), take a few short (5-15 minute), refreshing naps every day and almost never experience any sleep inertia, never mind sleep drunkenness. I sometimes wake in the morning without my alarm and if I'm still asleep when it goes off, I am up within 5 or 10 minutes. I feel I sleep easily, but I don't sleep deeply and I am frequently awakened.


I truly don't feel I have any problems with waking up, a problem that seems to be associated with idiopathic hypersomnia. I do, however, have a lot of trouble with staying awake, which seems more indicative of narcolepsy. I feel like my doctor saw my lack of SOREMs and because she didn't have a clear sense of what's actually going on, she'd call it idiopathic hypersomnia even though the rest of the symptoms don't seem to fit.


That said, I only want to figure out what's going on with my body and treat it in the most effective way possible. I am not committed to a narcolepsy diagnosis if that's not what's wrong with me.


I guess all of this was a long story to ask three things:


1. If you are presently diagnosed with narcolepsy, were you previously diagnosed with idiopathic hypersomnia?

2. If your diagnosis changed, what was the trigger?

3. If your diagnosis changed, or if it remains idiopathic hypersomnia, did it have any effect on your care and treatment?


Thankfully, I don't feel it's particularly urgent for me to have a proper diagnosis. I have no other symptoms or known health conditions, so I'm not too worried that my sleepiness is secondary to another condition. I was managing ok and holding down a job untreated with just scheduled naps and eliminating caffeine (gives me rebound sleepiness). Though the naps are inconvenient, my sleepiness is not threatening my livelihood or general health, it seems.


To my doctor's credit, she thought my sleepiness would benefit from treatment and prescribed Modafinil. The medication seems to be helping a lot so far, though I'm still trying to find a dose that doesn't make me jumpy yet lets me stay awake (this, incidentally, is another strike against the diagnosis of idiopathic hypersomnia, which apparently is not as responsive to medication as other causes of sleepiness). And though she was skeptical, she also provided a letter for my employer stating that I need nap opportunities during the day because I said naps are helpful. I am very grateful for these things which are already helping me feel a little more awake.


Thanks a bunch for reading.

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I am curious if you are on any medications that may have interfered with your sleep architecture. For example, some antidepressants and benzodiazapines reduce REM. If you happen to be on any of these, that could account for a lack of SOREM.

Your description of Cataplexy seems spot on.

My diagnosing sleep specialist was reluctant to give me a diagnosis even with 2 SOREMs. I pushed to have my concern of Cataplexy taken seriously. When she had a clear picture of Cataplexy, which is almost exclusive to N, she made the diagnosis of N with C.

My concern for you is that, if you have Cataplexy, it is currently untreated. Cataplexy can cause injury or create a dangerous situation. While you are in this gray area, please be careful of your safety. For example, I was sitting in a pool with my daughter and she suddenly made me laugh. I tilted over and started sinking, but caught myself before my head went under.

So, from here, I would make your concern for Cataplexy top priority. For some, it can take more than one MSLT to capture SOREM- it can be tricky. But if Cataplexy is clearly defined, the process may simplify.

I hope you get some answers soon.

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Hi "ilovenaps,"

I was diagnosed with narcolepsy 3 years ago.  I had the symptoms for years but I lived alone and didn't realize it was so abnormal to be sleeping all the time.  I didn't realize anything was "off" until people at work were asking why I was yawning all the time.  I never fell asleep randomly, as I always had control over my sleepiness, and I generally don't fall asleep unless I'm lying down.  I'm not the head-nodding type.  Finally when I mentioned to a doctor that sometimes I feel like I am falling asleep while I am driving (microsleep) and my car veers off to the shoulder when I'm on the highway without my ability to control it... the doctor referred me for a sleep study.  During the PSG, they found that I have sleep apnea, and they almost left it at that!!!  Thankfully, my follow-up appointment was with a really good doctor who said that my extent of sleepiness was not likely due to my sleep apnea, so she scheduled me for a PSG/MSLT.  


My MSLT sleep latencies were as follows:


Nap 1:  0.0

Nap 2:  0.5

Nap 3:  1.5

Nap 4:  1.0

Nap 5:  0.5


with 2 SOREMs during Naps 3 & 5.   I was on antidepressants and a mood stabilizer at the time so I don't know if those had any effect, which Hank had mentioned.  But I believe one of those sleep latency times is incorrect, because I actually fell asleep while they were doing the calibration  (blink 5 times/look to the right/look to the left) during the 3rd or 4th nap, then shortly woke again so they could finish the calibration and the tech didn't finish, just said "you can go to sleep now".  



To answer your first question, I was not diagnosed with Idiopathic Hypersomnia first.   The thing that I find strange is the way the sleep center staff got upset when I went outside in bright sunlight to move my car in the morning between my PSG and MSLT.   If you are truly narcoleptic, bright sunlight will not matter.  As you can see, even after being in bright sunlight and briskly walking 3 blocks to my car and back to the sleep center, I still had a 0.0 sleep latency for my first nap.  The fact that they have tinted windows in the waiting room to block out sunlight makes no difference at all to a narcoleptic.


However, my narcolepsy improved greatly since I got healing prayer at church the following year.  I will have another PSG/MSLT in a few weeks to see whether I still have sleep apnea and/or narcolepsy because I would like to treat my sleep apnea if it is still present.  I had refused to treat it because I thought it was "a drop in the bucket" compared to narcolepsy.  I believe that my narcolepsy status is now Idiopathic Hypersomnia, but we'll see and I'll let you know if my status changed!   What I remember from a few years ago is that it felt SO GOOD to sleep.  It felt better than sex.  It felt better than being awake and living life.  They wanted to treat me, but i couldn't see why I would want to be awake because I had nothing to stay awake for.  i was so happy to be at the sleep center for an MSLT because it felt like a big social event to me, like a sleepover! with other people in the waiting room with me, and movies and popcorn and conversation, and naps!  I told the tech it was like a sleepover and he looked at me like, "okay........weirdo".   


Narcolepsy affects your social life pretty drastically.  I used to take naps that lasted 2.5 hours.  I woke up refreshed but only for 1 hour before I'd have to nap again.

Now I am not looking forward to my next MSLT because I am not that tired and it will be a waste of my time.  Total difference in attitude, so I know my results will be different.  


What I can't understand is why people on internet message boards seem to WANT to be diagnosed with narcolepsy.  They make excuses for why they might not have fallen asleep faster.  If they are truly narcoleptic, no excuse or reason would prevent them from falling asleep.  I can't understand why anybody would want to be diagnosed with such an illness.  It is not sexy or something to strive for.  You can't MAKE it happen, and why would you want to?  It is a horrible, horrible condition.  The treatments for Idiopathic Hypersomnia and Narcolepsy are the same -  Stimulants.  I never heard that one is more responsive to stimulants than the other.  If you have cataplexy too, they can treat that with antidepressants, I think.


I have never had any other symptoms of narcolepsy other than EDS.   My muscles get weak when I have an adrenaline rush from fear or anger, but I'm not sure that's cataplexy or just a symptom of anxiety ("jelly legs").   I have never collapsed on the ground, but sometimes I voluntarily kneel down on the ground with my head down until my muscles get less weak.  


Best of luck to you!

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Livi, you are experiencing mild cataplexy...that's how mine started.

Nobody WANTS Narcolepsy. What they want is a diagnosis one way or the other so they KNOW what steps to take next. The Unknown is far scarier than the Known.

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I was desperate to receive the diagnosis which scared the !#@% out of me. I did not want it and I knew I had it - and I did not yet have the proof. I was horrible knowing something was very, very wrong with no proof or diagnosis that something is wrong. I was like waiting for a verdict when I knew I was innocent. Until the verdict (diagnosis) was made, I just did not know.


I agree with Ferret that what you described at the end of your post sounds like mild Cataplexy.  


Also, you mentioned the possibility of being "downgraded" from N to IH. I do not think it works that way. Idiopathic means of unknown cause. If you are N, then the cause is known. You may be very well managed and your tests results may improve since the last, but they will not negate the last results. The only way to downgrade to IH, I believe, would be to find error in the original tests to make them invalid. However, with 2SOREM it does seem valid.

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So they wouldn't prescribe you stimulants if you didn't have 2 SOREMs?   


The reason it is strange to me is because I had a very, very different experience.   When I was told to do another PSG with MSLT after my initial PSG that showed sleep apnea, I had overheard the doctor whispering to the receptionist "for possible diagnosis of narcolepsy."  The doctor saw that I overheard, and assured me that I was probably not narcoleptic.  I hardly knew what narcolepsy was at the time,  and i didn't give it a second thought.  Whatever happens, happens, in my book.   The medical tests will show it.   And whatever I have, I will be treated for.  

However, I think I know what you guys are saying, because when I did go in to get my result, I did hope for *something* just to show I wasn't making it all up.   I didn't want narcolepsy, but I wanted some scientific validation of my sleepiness so that I wouldn't feel like an idiot for being there for nothing.  Is that what you mean?   Or you don't trust that you will get treatment for what you have, if it's not narcolepsy?  


Maybe because I work in a research lab and do scientific experiments every day, I fully trust that medical tests will tell exactly what is going on.   Maybe other people don't have that level of trust in science and may question their results because of fear that the results are wrong and that they won't be treated for something that they think they have.   That's an unnecessary worry, in my opinion, unless human error is the cause, in which case the entire thing is videotaped and recorded so it can be reviewed if needed.


I think that I used to be narcoleptic and that my body has started making hypocretin again  -  that's my hope.  

Thanks for the input on the cataplexy~

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I have a more cautious view of test results than I previously held. I have worked in the medical field and put a high level of trust in my doctors and the tests I received. I now value the importance of a second opinion.

Several years ago I had a PSG for suspected sleep apnea by an ENT board certified in sleep medicine. There was no evidence of OSA but it did show significant sleep fragmentation and PLMS. I was then sent to a neurologist who tested me for elipeply with a 24hr sleep deprived EEG which was abnormal. It showed fronto-temporal slowing and bursts of bi-hemispheric slowing, microsleep and alpha intrusion. I was then sent for a CT and MRI to rule out brain tumor and aneurysm, which were negative. I received the diagnosis of a "sleep movement disorder" PLMD and prescribed Klonopin, a benzodiazepine, for sleep. It helped me sleep. When I continued to report daytime trouble concentrating and sleepiness, my dose was increased. When it continued, I was told to get more exercise. So I trained for and completed a triathlon. Then I started pushing harder with my neurologist because my Dx did not make sense to me. So, I went to a Sleep Medicine Specialist who told me I had been diagnosed with a symptom- PLMS were secondary to something else, not primary. What a total and complete shock- I had believed this for some time. I then learned that I was chemically dependant on Klonopin which required a 6 month slow taper to discontinue. And, while I was still on it my next PSG and MSLT would be invalid becuase Klonopin disrupts sleep architecture and supressed REM. They did however show an abnormally short sleep latency but of course no SOREM.

I went through six months of hell while going through benzo withdrawal which required 2.5 months off from work. Then I repeated the tests and it showed 2 SOREM. My worsening Cataplexy had been previously dismissed and then attributed to benzo withdrawal. I was desperate for confirmation that what I was experiencing was real- like a "not guilty" verdict.

So, I believe in the accuracy of test. However, the right tests are not always done. They do not always capture what is needed and need to be repeated. They are not always interpreted correctly. All doctors are not as equally qualified.

So, I think it is exceptionally important to be a well informed patient. To choose the right specialist. To get a second opinion when something does not sound right. And to ask a lot of questions and get a lot of answers.

If you actually started making hypocretin again, you would actually be the first on record. Once the cells are destroyed they are destroyed. I place a high value on hope, so I do not want to trample on that for you. However, it seems highly unlikely.

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I agree that it can be really difficult to get the right tests done with a symptom so vague as sleepiness, and I'm so sorry for all you had to go through to get the right diagnosis.  


But I was referring to people who actually had the PSG/MSLT who are frustrated that their result didn't turn out to be narcolepsy.   i don't understand why they think their test might be wrong, or why they are upset that they don't have a diagnosis of narcolepsy.  They have what they have.  It is what it is.  They can get treated for what they do have.

  You were talking about your medications interfering with your test results.  That could be the case, so it is a good idea to taper off them before a sleep study.  I was taking Prozac and Lithium at the time of my study which greatly disrupted my sleep and caused me some periods of insomnia during the night.  I still got the required 6 hours of sleep during the PSG but my sleep had been greatly fragmented and I had been awake for one hour from the insomnia caused by the meds.   It didn't change the fact that I had 2 SOREMs the next day, but maybe without being on the Prozac I would have had more SOREMs, who knows.  

I am now on a different medication which is also said to affect sleep, but it's a small dose and I will do my next study while taking it.  

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I'm not on any medication other than the new Modafinil, which was started after the test.


And to clarify, I don't want to be a narcoleptic. I also don't want to have idiopathic hypersomnia. I do, however, want to know what is causing me to have trouble staying awake.


What was positive about completing the PSG/MSLT was it confirmed my subjective experience of sleepiness objectively. For years I've been told that I am lazy because I take naps everyday. I have felt that if I just had more will power... or made my diet just a bit better... or got just a bit more exercise... or had slightly better sleep hygiene, or, or, or... if I did something else better I could just stop napping because I couldn't possibly be that sleepy. It's nice to be able to cut myself a bit of slack that way.


What is frustrating me is to hear that my sleepiness is idiopathic in nature after completing only one test. What is even more frustrating to hear is that idiopathic hypersomnia is actually a particular condition that has been described and has a relatively well-defined set of symptoms that do not match what I am experiencing. The hallmark symptom of IH seems to be long, unrefreshing naps, which is pretty much the opposite of what I complained to the doctor about. After reading about IH following my diagnosis, it does not seem to be a good fit for what I am experiencing.


As such, I am choosing to interpret my diagnosis as hypersomnia that is currently of unknown cause (idiopathic), because "idiopathic hypersomnia" per se doesn't seem correct. And as I mentioned earlier, given that only one test was performed I am not satisfied that the root cause of my sleepiness is truly undiscoverable. It's not that I don't trust tests and science, it's that I'm not convinced there has been sufficient testing done.


Further, unless a test is 100% specific and sensitive, there will be exceptions. From reading the forums and a bit of academic literature on the topic, it seems that some patients with narcolepsy do not initially present with 2 SOREMs and some people without narcolepsy will show 2 or more SOREMs on an MSLT. While 97% specific to narcolepsy, the criteria of 2 SOREMs and a sleep latency of less than 5 minutes on an initial MLST is only 70% sensitive (Aldrich, Chervin, & Malow, 1997). Medicine is good a developing diagnostic criteria to identify the majority of cases, but good science acknowledges when there are exceptions to those rules.



The goal of me writing here was for to better understand if misdiagnosis is common, if diagnoses typically evolve over time, and if there's really any difference in terms of treatment and care received if a narcoleptic is misdiagnosed with idiopathic hypersomnia. Maybe I truly have IH, maybe I have N, maybe I have sometime else entirely. But just in case this is a sneaky form of narcolepsy, I am curious to know if there are people who were initially diagnosed with IH but were later confirmed to have narcolepsy that received different (better?) treatment or care after their diagnosis was confirmed. What I am trying to do is figure out whether to let this IH diagnosis be, or whether I should push to find the root cause. Really, I just want the best outcome for my body, and if moving from an idiopathic diagnosis to a definitive one (what ever that may be) improves outcomes, that's what I want to pursue.


P.S. On the point about the bright sunlight in nap 5, I noted it because the doctor asked me what going on beforehand given the large discrepancy between that nap and the others. I explained to her I had been walking around and getting some sun and then rushed in because I was late. She said I shouldn't have been out in the sun, though no one else had mentioned that to me during the rest of the test. No "excuse," just a statement of what happened and the explanation I was given. In reality, I had actually been out in the sun prior to all 5 of the naps, but nap 5 was different in that it was the only one for which I hadn't had time to come in, use the washroom, and wait a few minutes for the techs to hook me back up to the machines. In the end, I don't think it really matters much, given that my sleep latency was below 5 minutes, an objective measure of sleepiness. 

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Well, the only thing I can tell you is that the symptoms described for narcolepsy and the symptoms described for IH do not fit me either.  i think that people experience their sleep disorders differently, and the difference between diagnoses is not so concrete or clear-cut.  


Narcoleptics are not "supposed" to take long naps, and I do.   But I don't fit the other symptoms of IH.   I also don't have the symptoms of narcolepsy other than EDS and mild cataplexy.  

So the impression I have is that there is a very fuzzy line between the two, and I don't really think it matters whether a person has narcolepsy or IH.   You already stated that you have scheduled naps at work.  That's more than I have as a narcoleptic.  You also are on stimulants.  I am not.   You are getting the treatment that you need for the diagnosis that you have.   I'm curious what other sleep tests you would like to have.

Of course, if you're trying to determine whether your sleepiness is due to a food sensitivity or some other cause, then it makes sense not to accept the diagnosis of IH right off the bat.   However, for narcoleptics, I don't see why more than one test would be necessary -  unless maybe your current medications are interfering.

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The only thing about tests and science that is variable is the human beings who are running the tests and the human beings who are interpreting them. Unfortunately human beings make errors.

Did any of you receive written instructions about how to prepare for the tests? What would happen during the tests? The do's and don'ts during the tests?

If not, it would be like having a random blood glucose done after eating two donuts and drinking a cappuccino when you're trying to rule out diabetes....duh! Should have been fasting...and that kind of thing happens all the time because people don't get told the rules.

Hank just posted a recent video and the speaker stated that they are pulling away from the sleep studies because of their unreliability.

The only way to know for sure is to have your CSF tested for Hypocretin or have clear cut Cataplexy.

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I did have detailed instructions and thought that was the norm.  Thanks for clarifying.


I did say this morning, ".....unless human error is the cause, in which case the entire thing is videotaped and recorded so it can be reviewed if needed."   


I would have loved to have an actual hypocretin level done -  unfortunately it requires a painful spinal tap.  


Best of luck to you all in determining what you actually have.   However, a diagnosis is just a label.  If the treatments are the same, then it doesn't matter what the label is.   

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"ilovenaps," it seems you know alot more about the diagnosis of narcolepsy than I do.


You stated, "some people without narcolepsy will show 2 or more SOREMs on an MSLT."    I was under the impression that the 2 diagnostic criteria for narcolepsy are 1.)  a short sleep latency, and 2.)  2 or more SOREMs during the MSLT.


It seems very simple and clear-cut to me, but a few of you have mentioned that doctors' interpretations can be different.  How so?


What is a "sneaky form of narcolepsy"?  


By the way, idiopathic hypersomnia IS its own diagnosis with its own set of diagnostic criteria.  Even if it's of unknown cause, it's still its own diagnosis.   You can always try to find what the cause actually is, but that would probably have to be done with other doctors and not the sleep center.  

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Hi Livi,


After receiving my diagnosis of IH, I had a look online to learn more about the condition. Instead of looking just to Wikipedia and leaving it at that, I had a look through the academic literature on the topic of IH generally and on the value of the MSLT as a test for narcolepsy and other causes of hypersomnolence.


What I found is that beyond narcolepsy with cataplexy, hypersomnolence is not well understood or described. Further, while the diagnostic criteria for narcolepsy are currently short sleep latency (<5 minutes or <8 minutes, depending on the clinician) and 2 or more SOREMs during an MSLT, the scientific literature indicates that these criteria should serve as guidelines only. Under these criteria, some patients with narcolepsy may be missed and some patients without narcolepsy (those with other disorders as well as healthy individuals) will test positive. While it does serve a purpose, the MSLT is not the be all, end all for evaluating hypersomnolence.


In my case, I was tested for narcolepsy and I met the short sleep latency criteria but did not meet the SOREM criteria.


A test such as the MSLT can be evaluated with two measures: sensitivity and specificity.


Sensitivity is a measure of how well a test identifies true positives. In effect, it indicates how many patients who actually have a particular condition will test positive using that measure. A criteria of two or more SOREMs and a sleep latency of 5 minutes or less on an MSLT is about 70% sensitive. In other words, the test will positively identify only about 7 in 10 narcoleptics during a particular test. This tells us the other 3 in 10 narcoleptics will exhibit one or zero SOREMs and/or a longer sleep latency. As such, there is a significant risk of false negative with this test. (Aldrich, Chervin, & Malow, 1997). Douglas (2001) notes that even after repeat MLSTs, the number of narcoleptics demonstrating a mean sleep latency of < 8 min and two or more SOREMs will not rise above 80%. When I referred to a "sneaky form of narcolepsy," I was referring this 20%-30% of cases that do not, and may never exhibit at least 2 SOREMs.


Specificity is a measure of how well a test identifies true negatives. In effect, it indicates how many patients without a particular condition will test negative using that measure. A criteria of two or more SOREMs and a sleep latency of 5 minutes or less on an MSLT is about 97% specific. In other words, if you tested 100 individuals without narcolepsy (who may or may not have other medical conditions), 97 of them will not meet this criteria and will test negative. While the specificity of this test is better than its sensitivity, we still find 3 out of 100 individuals without narcolepsy would test positive using this criteria. (Aldrich, Chervin, & Malow, 1997).


The moral of the story, if there is one, is that nothing is totally simple and clear-cut when it comes to the human body.


Also of note is of the 2,083 subjects tested in this particular study I am referring to is that due to the fact that narcolepsy is a rare disorder, 30% of those who met the diagnostic criteria of two or more SOREMs and a sleep latency of 5 minutes or less on an MSLT did not have narcolepsy (Aldrich, Chervin, & Malow, 1997). In other words, if a doctor saw 10 patients who met the criteria of short sleep latency and at least 2 SOREMs, in the end 3 of them would not have narcolepsy. As such, according to Aldrich et al. doctors should not use MLST findings alone to confirm or exclude a diagnosis of narcolepsy.


I do not contest that IH is a diagnosis unto itself. What I am uncomfortable with is the fact that this diagnosis is characterized by difficulty waking up and unrefreshing sleep/naps, which is not what I am experiencing. With all of this in mind, I had written here to ask about whether a wrong diagnosis of IH negatively impacts treatment or care for individuals who later turn out to have N, just in case that's me. In the end, it may turn out that IH is just the ticket, or maybe I have something else going on entirely. However, as it stands right now I'm not 100% convinced that IH is what is going on for me and was inquiring to get advice on whether to dig deeper or not.


In case anyone is interested, Douglas (2001) has summarized these findings about MSLT testing, as well as lots of other information about the causes of sleepiness in an easy to read article that is freely available: This piece was published in the American Journal of Respiratory and Critical Care Medicine, so it's reputable information.


If you're interested, you can view the abstract of the Aldrich et al. (1997) study I cited above here:

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ilovenaps, that's a really good explanation about the sensitivity and specificity of tests, and how they relate to the MSLT. Your explanation of those things, matches my understanding of those things too. I agree that the human body is complex, and is not simple or clear cut enough to always fit into the test criteria.


I was diagnosed with narcolepsy (based on my clinical symptoms, as well as my PSG/MSLT) without meeting the positive MSLT criteria. My duration of initial "sleep" in the naps wasn't long enough to count as "sleep " in the MSLT (they were "micro-sleeps"). For these "micro-sleeps" to be seen by my doctor, involved him looking at the raw data/brain waves, rather than just reading the report that is generated by the computer and/or technician. Your description of your symptoms sounds very much like mine.


Often IH and Narcolepsy are treated in the same way, so you won't necessarily be disadvantaged if you actually happen to have narcolepsy, but are treated for IH. Except, as Hank mentioned, if you have cataplexy that needs treatment. Perhaps if you continue to experience things that could be cataplexy, you could discuss those symptoms with your doctor again.

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I'm sticking to my opinion, you can have yours as well.   If your 5th nap was 11.9 minutes latency so I'm not sure how you "met the short sleep latency criteria."  But I do realize you have your reasons that you think are legitimate as to why your latency was so long.


Good for you for reading the literature.  It's great that you seem to enjoy analysis.  I do as well, and tend not to even look at papers prior to year 2000 since they are outdated and don't have the most accurate information (maybe 30% inaccuracy  ;))


I disagree with some of your interpretations of the paper regarding specificity, but I don't have the time to discuss.  Every test in the history of medicine has specificity and sensitivity parameters.  The general reason that some people with narcolepsy have a false positive is if the MSLT is administered without a PSG the night prior, which detects disorders such as periodic limb movement, sleep apnea or any other sleep disorder that can affect the patient's level of sleepiness the next day.  Also, questionnaires given by the doctor's office should obviously be answered accurately by the patient, for example if he/she has been seriously sleep deprived during the previous week or any other obvious circumstances that would affect the PSG which would then possibly negate the MSLT.  If the MSLT is done all by itself without the PSG, there can be no confidence in accuracy.  If you don't believe your test results for IH, then I hope you can find what the cause of your sleepiness is.  I'm not sure why you wrote on this board -  you said you were wondering whether a diagnosis of IH impacts treatment, but the treatments for IH and narcolepsy are the same -  your doctor could tell you that -  and that question was answered from the beginning.  Like I said, the diagnoses of the two are just labels.  

Best wishes to you in finding a diagnosis that you can believe and that helps you the best way possible.




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My sleep latency times were longer than Ilovenaps. On my 5th nap I had a sleep latency of 12 or 13 minutes and then I had a SOREM during that nap.

Anything under 5 minutes is diagnostic. Anything under 10 minutes is abnormallly sleepy. 20 minutes is normal.

I understand why Ilovenaps posted her questions- because she has questions about her diagnosis- and that is a main purpose of this forum. Especially in light over concerns of possible Cataplexy, understanding her diagnostic process is important.

When I went through my first round of tests, I was still not aware that I even had Cataplexy- it just never crossed my mind. I had never heard of Cataplexy.This forum was particularly helpful for me in clarifying what I was experiencing. Without that understanding, I would have continued denying symptoms that I actually had been experiencing. I knew I had clumsy falls and injuries which were embarrassing but never considered them as symptoms, so I did not mention them. I just couldn't figure out why I kept dropping my coffee and breaking my favorite mugs. I knew I heard music when I woke up sometimes (like my own personal XM radio) but I was not bothered by that or considered it a symptom, so I never complained about it.

Questioning has made me a better patient. And that has helped doctors to be better at helping me.

Livi, it is generous of you to allow Ilovenaps her opinion. And from my experience, there is value in second opinions and questioning.

Diagnoses of Narcolepsy are not always cut and dry. For some, like me, it was a process instead of an event. If I had questioned my original misdiagnosis, I would have gotten to the correct answer sooner. Coming to terms with a diagnosis also runs its own course and that is also a purpose of this forum.


While the treatment for N and IH may overlap, they are not exactly the same. Cataplexy is another story. And, Xyrem is not licensed for IH, although it may be prescribed. So, I think questioning and wrestling with it is important. If we are going to live with a diagnosis of IH or N or C that none of us would choose, then we can at least be confident that it is correct.

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What you may have is hypersomnolence due to orexin deficiency -- a mild form or narcolepsy, or narcolepsy that is still in the development stage.  This often gets lumped into the IH category.  The more orexin you've lost, the more disorganized your sleep architecture becomes, and the closer REM appears when you fall asleep.  I was diagnosed with IH but now I'm showing signs of mild cataplexy, so they changed my diagnosis to narcolepsy.

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I understand being frustrated with an IH diagnosis because the medications Medicare will cover for this do not work for me. I am about to undergo my second MSLT and AM hopeful for a either a Narcolepsy diagnosis (NOT because I wish for this, but because I was the proper treatment) OR to find out if there is an underlying cause to the IH that may be either cured or better treated.


The only medication that seems to work for me is Provigil (have been put on Ritalin (ARGH!), Nuvigil - which does keep me awake but the side effects and other personality problems a huge issue... this one IS approved and also tried massive doses of caffeine... which at this point has absolutely no wakefulness affect).


Provigil ALSO seems to help with getting a better night's sleep as well as improving congnitive function, memory, energy during the day without causing a "speedy" effect. I feel better and more functional than I have in YEARS when taking the med. First script approved and it was life-changing for me. But they refused any further refills. Ouch.


Do I have IH or Narcolepsy? I have no idea. But as mentioned by others in this forum, I ignored symptoms for years, not realizing it was NOT normal to experience them. Weird stuff like:


- just suddenly falling .... knees buckle and I'm down. Sudden loss of hand function that cause me to drop or spill things and multiple other things like that.


- extreme daytime sleepiness which started out intermittently but now is constant as well as lack of overall energy


- cognitive issues that worsened to the point where it caused me to lose my job.


-forced sleep attacks. THIS is what sent me finally to my doctor because when I fell asleep with no warning and no apparent drowsiness until just prior while DRIVING and woke up wide awake to find myself driving on the curb with the only thing keeping me from killing myself and others was my tires hugging the curb.) Have fallen asleep while eating. Often as a passenger in a car. On the toilet, At our Christmas celebration and my daughter's birthday dinner and other family functions. And often when sitting, watching TV and the minute I pick up a book, I am toast. Even after a full night's sleep. These started intermittently as well. But are now pretty constant. at my first sleep study I was not experiencing this during the time they said to fall asleep BUT I kept having micro naps in between those times ... sometimes they noticed and told me to wake up and sometimes they didn't even notice. But they weren't monitoring me at those times. ALSO had been on meds that now I found out can affect results of MSLT. 


- Started "hallucinating/dreaming" just prior to sleep. And sometimes when awakening. This has also been intermittent and is now pretty much all the time. So I am hopeful at this new sleep study, they will see that early REM sleep.


-And the WEIRDEST thing is the addition of these night-time hunger attacks. Literally attacks! I become ravenous and if I eat, I wake up with food all over my pillow and in my mouth. So I try to ignore these as best as possible.


-And other symptoms that I didn't even consider would be due to a medical condition but later found explained on this and other narcolepsy/IH sites. 


-But IH or Narcolespy? My naps short and very refreshing. NO trouble falling asleep at night. In the morning I am now feeling for hour that I am in a foggy sleep state. Not actually dreaming, but in a daze. Sometimes just staring off into space, sometimes trying to concentrate but unable, unable to hold my focus or a decent conversation, just basically unable to think clearly and function. And this usually improves later in the day but wow, does it make me useless for a large part of the day. Sometimes all day. PROVIGIL also eliminates this.


So do any of us WANT to have a disease or medical condition. NO! But correct diagnosis will lead us to the proper treatment or cure and also will help our friends and family understand WHY we are the way we are and that we are not lazy or unmotivated or crazy.

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