Assessment of Sleep Disorders DR HUGH SELSICK

Assessment of Sleep Disorders DR HUGH SELSICK

Goals Understand the importance of history taking Be able to take a basic sleep history Be aware the technology used to assess sleep disorders. Understand the uses and limitations of the way we use that technology.

History Clinically we divide sleep disorders into: Insomnia Hypersomnia Parasomnia Circadian Rhythm Disorder All of these can lead to fatigue during the day.

Typical Night What time do you go to bed? What do you do when you go to bed e.g.. read, watch TV, turn lights out straight away? Is there a bed partner? How long does it take to fall asleep? (Sleep onset latency). How many times do you wake during the night? What wakes you? How long are you awake for each time? What do you do? (Wakefulness after sleep onset). What time do you wake up in the morning? Is this spontaneously or to an alarm? What time do you get up? (Rising time-bed time = time in bed). How long do you think you sleep in total? (Total sleep time). TST/TIBx100= Sleep efficiency

Typical Day How do you feel during the day? What time of day do you feel most tired and least tired? Do you nap during the day? Are these planned or unplanned naps? When do they occur?

Fatigue vs Sleepiness It is vital to distinguish between fatigue and sleepiness. Fatigue has innumerable causes; sleepiness is very likely to be due to a sleep disorder. Here the Epworth Sleepiness Scale can be helpful as it gets the patient to focus on whether they actually fall asleep. The ESS asks the patient the likelihood of falling asleep in eight scenarios. If the patient has not been in a particular situation in recent times they are asked to imagine how likely they would be to fall asleep if they had. There is some debate as to where the cut-off between normal and excessive sleepiness is: usually excessive sleepiness deemed to be from 11 or 12/24 up.

0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing SITUATION CHANCE OF DOZING Sitting and reading Watching TV Sitting inactive in a public place (e.g a theater or a meeting) As a passenger in a car for an hour without a break Lying down to rest in the afternoon when circumstances permit Sitting and talking to someone Sitting quietly after a lunch without alcohol In a car, while stopped for a few minutes in traffic

0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing SITUATION CHANCE OF DOZING Sitting and reading 2 Watching TV 3 Sitting inactive in a public place (e.g a theater or a meeting) 2 As a passenger in a car for an hour without a break 3 Lying down to rest in the afternoon when circumstances permit 3 Sitting and talking to someone 2 Sitting quietly after a lunch without alcohol 2 In a car, while stopped for a few minutes in traffic 1

0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing SITUATION CHANCE OF DOZING Sitting and reading 0 Watching TV 1 Sitting inactive in a public place (e.g a theater or a meeting) 0 As a passenger in a car for an hour without a break 0 Lying down to rest in the afternoon when circumstances permit 0 Sitting and talking to someone 0 Sitting quietly after a lunch without alcohol 0 In a car, while stopped for a few minutes in traffic 0

0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing SITUATION CHANCE OF DOZING Sitting and reading 1 Watching TV 2 Sitting inactive in a public place (e.g a theater or a meeting) 0 As a passenger in a car for an hour without a break 0 Lying down to rest in the afternoon when circumstances permit 2 Sitting and talking to someone 0 Sitting quietly after a lunch without alcohol 1 In a car, while stopped for a few minutes in traffic 2

Sleep Apnoea Do you snore? Has anyone told you that you stop breathing in your sleep? Have you ever woken up choking? Do you sweat a lot in your sleep? How many times do you pass water at night? Do you often wake with a headache?

Restless Legs and Periodic Limb Movements Do you get a sense of discomfort that makes you want to move your legs? When is it worst? (RLS worse at night) Does movement temporarily relieve the discomfort? Does your partner complain you have twitchy legs in your sleep? When you wake are there signs of restless sleep e.g. blankets on floor, sheets pulled out? Do your legs twitch of their own accord in the evenings or are you woken by leg twitches?

REM Parasomnias Do you have nightmares? How often? Do they wake you or make you afraid to sleep? Give an example. Do you ever fight or shout in your sleep? Have you ever hit the wall or thrown yourself out of bed? (REM Behaviour Disorder) Do you remember dreaming and did the actions correlate with the dream? What time of night does it occur? (More likely in second half of night)

Slow Wave Sleep Parasomnias Do you ever sleep walk/eat etc.? Do you ever wake up screaming or feeling afraid? Is there any dreaming associated with it? (Typically not) When does it occur? (Typically first half of night)

Nocturnal Epilepsy Does your partner report any unusual movements during the night? Are the movements always the same? (Stereotypical movements) How quickly do they start and finish? (Tend to be 2-3 min) Is there a history of daytime seizures? How frequently do they occur? (Tend to occur several times a night, most nights).

Hypnagogic/Hypnopompic Hallucinations As you are falling asleep or waking up, do you ever feel like there is an evil presence in the room, see things, feel things or hear things that aren t there? How often do they occur? (Most people have them occasionally; frequent hallucinations can be a sign of narcolepsy)

Sleep Paralysis As you are falling asleep or waking up do you ever find you are completely paralysed and can t move or talk? Does it feel like you can t breathe? If you had to lift your finger one inch or say a word could you? (This is to differentiate it from sleep inertia). How often does it happen? (Sporadic episodes are benign, but frequent episodes may indicate narcolepsy)

Cataplexy If something makes you laugh, makes you angry or surprises you do you suddenly go weak and have difficulty holding your head up, do you legs turn to jelly etc.? Is your vision/hearing affected? (Vision affected in cataplexy; hearing not affected). Do you go weak or do you feel sleepy?

Technology Actigraphy Oximetry Respiratory study Polysomnogram

Actigraphy Small wristwatch with 3D accelerometer. May have light sensor and event button.

Oximetry Measures oxygen saturation and pulse rate through the night.

Respiratory Study Pulse oximetry Nasal air flow Chest and abdominal movement bands

Polysomnogram EEG EMG (typically submental) EOG Can add: ECG Respiratory channels (airflow, oxygen saturation, respiratory movement bands) Limb EMG Video Extended montage EEG.

Using Actigraphy Can be used to monitor periodic limb movements at home. Mostly used to monitor sleep/wake cycles in community. Good for confirming diagnosis of circadian rhythm disorders. Useful for monitoring sleep prior to a polysomnogram. Not fully validated in all conditions.

Oximetry Good screening tool for OSA/CSA. Doing two nights adds value in terms of identifying positional or REM related OSA. Pulse rate variability can indicate sleep stages, sleep disruption and periodic limb movements. Not sufficiently sensitive if BMI<25.

Respiratory Study More accurate and detailed respiratory assessment. Better at differentiating obstructive, central and mixed apnoeas. Can be done at home. Can detect sleep apnoea in slimmer individuals.

Polysomnogram 1 Gold standard Only technique that measures actual sleep. Therefore good for measuring the impact of a sleep disorder on sleep. Overnight polysomnogram used to monitor sleep architecture, parasomnias, sleep apnoea, PLMS, epilepsy (with extended montage), insomnia. Used to quantify sleep.

Polysomnogram 2 Multiple Sleep Latency Test: series of daytime nap opportunities. Used to quantify daytime sleepiness and look for early onset of REM sleep (suggestive of narcolepsy). Limited by differing protocols, artificial environment; anxiety can cause false negatives. Maintenance of Wakefulness Test: series of challenges to stay awake. Used to monitor patient s ability to remain awake e.g. when driving. Unclear how well it translates into real life. 24 hour EEG: used to detect sleepiness, epilepsy and quantify total daily sleep time. Can be useful to differentiate between sleep attacks and dissociative episodes.

Biochemical Tests RLS/PLMS: Ferritin, folate, B12, U&E, glucose CSF orexin HLA typing for narcolepsy: HLA DQB1*0602

Conclusion The assessment of sleep disorders is largely done in the consulting room. Sleep studies are largely for confirmation. A decent sleep history can be taken in a few minutes and should be part of the assessment of any patient with daytime fatigue or a subjective sleep complaint.

Questions?