Assessment of Sleep Disorders

Welcome to another Psych Matters podcast from the Royal Australian and New Zealand College of Psychiatrists. Psych Matters is a series of discussions on training and practice issues facing trainees and fellows of the college and other important topics in mental health. Sleep disorders are often misunderstood and underdiagnosed. Understanding sleep physiology is key to diagnosing and treating sleep disorders. Sleep disorders can be categorized into disorders of initiating and maintaining sleep, disorders of excessive sleep, parasomnias and disturbances of the sleep cycle. In this episode of Psych Matters, Dr. Robert Kaplan takes us through the diagnosis, approach and treatment methods for the various sleep disorders including insomnia, sleep apnea, narcolepsy, restless leg syndrome and REM sleep behavior disorder. We acknowledge Aboriginal and Torres Strait Islander peoples as the first nations and the traditional owners and custodians of the lands and waters known as Australia and Māori as Tangata Fenua in Aotearoa. We honor and respect the Elders past and present who weave their wisdom into all realms of life. I'm Robert Kaplan. I'm a forensic psychiatrist based at Western Sydney University. My original training was in liaison psychiatry which is where I learned a lot about sleep and about dealing with pain. So I've always had an interest in sleep disorders and I've also worked at sleep clinics. I always emphasize to medical students and trainees how little they are taught about sleep disorders and how important it is to have a good understanding. It's also worth pointing out that every resident, every registrar and every intern always has a sleep disorder from doing night duty. So the more you learn about this the more you can help yourself. Sleep occupies fully one third of our lives and yet is very poorly misunderstood. In fact it is only in the middle of the 20th century that we really were able to get into what constitutes different types of sleep and break it down. This has led to huge developments in that we can now assess sleep in every stage of the sleep cycle and this makes it very easy to make a diagnosis. Now you get two kinds of sleep problems. The first one is the obvious one. Either physical or psychological problems can interfere with sleep. It makes sense doesn't it, that if you're anxious, if you're fretting, if you're in pain you won't be able to fall asleep and this may wake you later. The second aspect is of course what we call a primary sleep disorder and here is something of a lacuna in the training of doctors and for that matter psychiatrists in that if you look at medical school curricula they never ever get a full lecture or a full set of teaching on how to assess sleep. So that's what I'm going to do now. The most important rule about sleep disorders is that if you understand sleep physiology everything falls into place. So let's look at how sleep operates. Much of it is very sensible. When you lie down and go to sleep you go to different levels of consciousness so you go from stage one which is the lightest all the way down to stage four and that's the deepest level of consciousness and there's a side issue to this. It's been recognized for many years by police and security that if you want to pick up somebody without a struggle and find them confused and not knowing what's going on you hit them at about two or three o'clock in the early morning when they're in stage four sleep. Now you go from stage one down to stage four after that you go into the famous REM sleep. Now what is REM sleep? Strictly speaking it means rapid eye movement and yes if you shine a light on somebody's eyelids you will see that they are flickering backwards and forwards but that's only the surface manifestation of sleep disorder. What is actually happening in REM sleep is almost like a physiological explosion. Everything goes wild breathing, gastric movements, heart rate, pulse, muscle tension, that kind of thing. So the intention in REM sleep is to clean out your short-term memory. It's a bit like somebody coming to an office room at the end of the day and emptying the bin so that the room is ready for the next day. This is why many people who have sleep disturbance for whatever cause will come in saying I think I'm losing my memory I can't concentrate. So REM sleep is terribly important. It's got a few other aspects to it. In the old days in sexual medicine it was the only way of knowing if men had an organic cause for impotence because you get erections during REM sleep. So they would put somebody in a sleep lab as soon as they went into REM sleep they would move in lift up the pillows and take a Polaroid picture of what they found. So REM sleep is terribly important. The other thing about REM sleep is that you have complete muscular paralysis. Why? Because you're disturbing your forebrain and that area of your temporal lobes where you keep memories. What happens when you disturb these memories? You dream you have very vivid dreams. When you have vivid dreams you've got to remain paralyzed otherwise you act out on them and as we will see this can have lethal consequences. So the sleep cycle goes stage one two three four REM sleep for the next couple of hours in the early morning REM sleep predominates and then towards the end of the time you slowly drift out of REM sleep and by the time you wake up whether it's 6 a.m. or 8 a.m. you've just come out of stage one sleep. The important thing about sleep medicine is this dichotomy that people have with the sleep cycle. What does that mean? Most people think your sleep is what 10 a 10 11 p.m. to 6 7 a.m. but it's not it's a 24 hour cycle and this can lead to some diagnostic confusion because let's say somebody has sleep apnea which leads to a lot of disturbed sleep at say 2 to 3 a.m. They will not be aware of it but at about say 3 4 p.m. in the afternoon they'll suddenly be struggling to stay awake and equally so if they fall asleep then it disrupts their sleep cycle and they can't get to sleep later that night. So it's very important to understand two things about sleep physiology one you cycle through from stage one to REM sleep and back again and two it's a 24 hour cycle and if you have a disturbance at one point along there it will feed down the cycle. Now how do we classify sleep disorders? Very simple according to disturbance of the sleep physiology. So the first category is called for convenience dims disorders of initiating and maintaining sleep pretty obvious stuff. Well everybody can have something that can stop them from falling asleep but maintaining sleep is a different problem. Now what are the key issues to look there? If somebody's unhappy or fretful we're sure they won't be able to fall asleep but if they've got a significant depressive illness they will have this classic middle insomnia followed by early morning waking. There are other causes of this including narcolepsy but that is the significant one and it's worth remembering that difficulty with sleep what we call insomnia is the commonest problem presenting in primary care after pain and of course this spins off into a whole medical economic and social problem with people being put on incorrect medications which often lead to addiction and permanent sleep disruption of the sleep cycle. Now the second category again to cheat to use the initials is does disorders of excessive sleep and this is something that's become much more noted lately in sleep clinical medicine because it's a very common problem that people come in and say I'm tired I've struggled to stay awake all day and of course there are a range of conditions that are associated with this. The first one to look at is again sleep apnea. Now what actually happens in sleep apnea? For anatomical reasons the back of the throat is constricted this can be due to being overweight, use of drugs, bad dentition, problems with jaw but really the combination of being overweight, smoking and drinking is pretty much the key factors. Somebody with sleep apnea can have 50 to 100 episodes during a night's sleep when they black out by what I mean is they become hypoxic to the point that they can almost die in their sleep. The problem is they don't know that. The other side of the issue is the call sign of sleep apnea is heavy snoring. Now snoring is pretty common in the community but you'll know somebody's got sleep apnea when they tell you when they go to a campsite they have to move their tent outside the fence or when they go to a hotel they get kicked out of their room so loud snoring with periods of apnea is just about diagnostic. So often your person with moderate sleep apnea will come to you and they won't say they snore they won't say they have these apnea thing they'll say my memory is going I've become impotent and I can't stay awake during the day. In fact if you work with sleep apnea patients you'll find it quite alarming there'll be a sleep in your waiting room and as I saw in a number of cases I turned around to get a pen and while talking at the desk and by the time I turned back they were asleep again so hypersomnia is a classic symptom. We can talk about treatment of sleep apnea later because it's pretty well known now what to do. Other things that cause excessive sleepiness firstly of course there is narcolepsy. Now it used to be thought that narcolepsy is an extremely rare condition this is not true Australia has more people with narcolepsy than it has multiple cases of multiple sclerosis and narcolepsy often presents to psychiatrists or even to the law first because people have these episodes of apnea of sorry of catalepsy where they collapse and then wake up as if nothing's happened and sometimes this can be picked up in public as some sort of strange behaviour. The other area of excessive sleepiness and tiredness is very much in the news this is the problems with conditions like chronic fatigue syndrome and fibromyalgia. Now this is not the place to get into a long discussion of the issues to do with chronic fatigue but it's worth pointing out that all the good research has shown it consists of three elements neuromuscular in other words muscular fatigue pain and difficulties walking secondly psychological anxiety and depression and thirdly sleep disturbance so it is a treatable condition if people will accept it's got these three elements and they should be looked at. One of the hazards that's now presented in this age of mass prescribing of amphetamines for just about any condition including ADHD is that some of them get put on amphetamines and well you can imagine the end result of that. So these are some of the conditions that lead to excessive sleepiness. The third category the sleep physicians like to call it things that go bump in the night and these are known as parasomnias. Now parasomnia is any behavior associated with sleep probably the commonest one psychiatrists will encounter is restless legs why because of course a lot of the medications we use cause this but restless legs never occurs on its own it's associated with tossing and turning and sleep twitching and jerking and bruxism grinding of the teeth so you sometimes can see just when you sit down with someone who's got this kind of problem that they've got a beautiful horizontal edge to their teeth which tells you they've been grinding it down. So the official term is periodic limb movement disorder and it can be a serious condition it makes people tired it makes people moody and they can grind their teeth so much that they destroy their TMJs so well worth looking out for. What most people remember about parasomnias of course is sleep talking and sleep walking and there's again an urban myth that people who sleep walk is it's a thing that happens when in childhood you grow out of it well not necessarily so and you often find if you've got an adult with sleep walking firstly it's associated with sleep talking and remember people with sleep talking don't necessarily articulate clear sentences they grunt and moan that also counts as sleep talking but there's a family history and they may have done it in childhood. Why is this so important? Because sleep walking kills it's the commonest cause of death in sleep and occasionally it's a cause of murder in sleep so sleep walking should be taken very seriously why do people who sleep walk get into trouble well they walk through windows they fall downstairs they go out on the road and they get knocked by cars so it's something not to underestimate there's some very good treatments but that's something for another talk. I hope that you're enjoying this podcast if you have a topic suggestion or would like to participate in a future episode of psych matters we'd love to hear from you please contact us by email at psych matters dot feedback at rnzcp.org what are the kinds of parasomnias are there there's of course enuresis bed wetting and there is nocturnal eating syndrome now this is very interesting and it's got some amusing aspects but in the long run it's not particularly funny what happens is that somebody gets up during the night and they'll go to the kitchen they'll open the fridge door they'll pull out food they might leave a terrible mess they might eat food they don't even normally like and sometimes they'll take it back to bed with them what happens the next morning they wake up and their partner is incandescent why have you done this why have you brought all this mess here and they have no idea that they've done it so this is a variant on sleep walking it's often associated with more severe pathology such as depression or eating disorders and the nice part about it is that it is treatable completely perhaps the most notorious parasomnia is called REM sleep behavior disorder now what happens here is you go into REM sleep and the muscular paralysis mechanism breaks down so you act out on your dreams and this started with a famous case many years ago in London where a man woke up to find he had strangled his wife and had no idea of what had happened and he would have been charged for murder had they not been able to show that he had REM sleep disorder who does it occur who gets it well there's a very nice statistic 90 percent of cases occur in men over the age of 60 with neurological or pending neurological disorders in other words Parkinson's dementia even Huntington's Korea so if somebody's got it and they don't appear to have anything wrong with them they need to be followed up very carefully and REM sleep behavior disorder is again very treatable interestingly it's the old style tricyclics particularly anaphronal that works very well but some of the newer medications do this as well so the other parasomnias but I want to go on to the last category now which is called whimsically cycles and this is disturbance of the sleep cycle in other words that 24 hour band we were talking about and every doctor will know this because of course they get night shift syndrome when you work at night it really throws your sleep pattern out of sync and it's now been recognized that this is a significant cause of both physical and psychological pathology and all sorts of steps are being taken to learn how to treat this or to deal with it because of course we can't stop people having to work on night shift what's another example of sleep cycle disorder jet lag anybody who travels will know all about that and they'll probably know that the new go-to treatment is melatonin and why melatonin because melatonin is secreted by the pineal gland and yes the pineal gland is the one that regulates your 24 hour cycle melatonin is still being understood it's very safe to use but nobody's entirely certain how well it works or what's the right dose there's one other type of sleep cycle disturbance that's interesting and this comes up in child psychiatry there's a kid who finds every morning it's a terrible struggle to wake up and to go to school and they're grumpy and miserable and yet as soon as the holidays come and they're allowed to sleep on they are perfectly well and this is called delayed sleep phase disorder what does that mean very simple your body clock for various reasons is set at the wrong time and it can really upset young people it can mess up their school life it can lead to mood disorders and just behavior problems and it is quite tricky but there is a protocol to work with their parents and with the kid to reset their sleep clock and there is some use for medications now that's a very quick rundown on diagnosis and categories of sleep disorder there's one last thing I want to talk about and this is what's known as psychophysiological insomnia what is this this is a kind of insomnia that arises for personal social or psychological reasons in other words unhappiness frustration restlessness the problem is that the key group get this are adults let's say from mid 60s or even earlier onwards and often they lead very empty lives so what they want when they go to bed at night is essentially to be anesthetized from 7 p.m. to 7 a.m. and here's where the problem starts they go to a doctor and they get put on a benzodiazepine and what happens if you keep taking benzodiazepines you completely wreck your sleep cycle and you create an artificial sleep architecture and of course in the long run you get addicted let me give you an example if you take Xanax for two weeks you can still see the changes in the sleep cycle if you do a sleep EEG six months later so there is a use for benzodiazepines in acute situations somebody's gone through a terrible trauma somebody's coping with grief and bereavement perfectly reasonable to use it it's the long-term use I don't need to remind people that valium diazepam has a 72 hour half-life so let's say you take 5 milligrams one night well you've got 30% of it left there the next night when you take another valium and you can see how it builds up in your system after that so psychophysiological insomnia is essentially an epidemic in the suburbs and it needs a really motivated intervention rather than just dishing out tablets it needs to look into their life it needs to teach them about sleep hygiene and also destroy this basic myth that people have if I don't sleep I will not only be unhealthy I could die that's absolute rubbish in fact anyone can cure their insomnia this way if they force themselves to stay up till they naturally fall asleep it doesn't matter how long it takes and it will not harm their health at all one further thing about treatment of sleep disorders is the so-called Z drugs I must say they've had a very bad press and for good reasons they call also cause all sorts of sleep disturbance including violent and suicidal behavior so they are used very freely in the community but I would urge anyone to be very cautious about that so that is a quick summary of how to assess and understand sleep and I'll end off by repeating the basic principles sleep is a 24-hour cycle and if you get disturbance at one point it can manifest visibly at another point secondly if you understand basic sleep physiology you can never really go wrong because all you're doing with a sleep disorder is looking at what point the sleep physiology is disturbed finally the problem of insomnia is inescapable whether you're an intern or resident in practice working in a hospital or an old age home and it's very important to take this seriously rather than just dishing out more tablets and hoping it will all go away because it won't unless you deal with it properly one last point about medication is there's a tendency to use tricyclic antidepressants as sleeping agents often say amitriptyline at a dose of 10 or 25 milligrams now the pain clinic people love doing this how much benefit this has for pain I really don't know because I don't think there's any convincing proof but the problem with using it for sleep is it does make people help people to sleep but it's got too many side effects and it's not worth it dry mouth low blood pressure constipation and particularly in old people they fall over they can even get arrhythmias so for producing sleep avoid the tricyclics you may have other reasons to use them properly that's fine but not for inducing sleep so on that note I'd like to finish off and wish everybody well and hope that this has brought some insight into the world of assessment of sleep thank you we hope you enjoyed this episode of psych matters feel free to share it with others and keep an eye out for future episodes psych matters is produced by the royal Australian and new zealand college of psychiatrists