Sleep disorders

By : Dr. Alireza Safaeian

Occupational Medicine Specialist

Physiological basis of sleep

Definition :sleep is a behavioral terms as a normal, recurring, reversible state of loss of the ability to perceive and respond to the external environment.

Physiological basis of sleep

• Sleep stage and cycles:

NREM (stage 1-4)

REM

• A night’s sleep in adult :4-6 cycles

• Each cycles :about 90 min

Physiological basis of sleep

Physiological basis of sleep

Physiological basis of sleep

EEG wave frequencies:

• Beta: 14-30 Hz (during wakefulness & drowsiness or in sleep with sedative-hypnotic)

• Alpha: 8-13 Hz (during quiet alertness with eye closed)

• Theta: 4-8 Hz (the most common sleep frequency)

• Delta: < 4 Hz (20-25% in stage 3 & >50% in stage 4)

Physiological basis of sleep

Wakefulness with closed eyes

• More than 50% of epoch is alpha waves

Physiological basis of sleep

NREM

synchronized, rhythmic EEG activity, partial relaxation of voluntary muscles and reduced cerebral blood flow, heart rate, blood pressure and respiratory tidal volume fall.

Physiological basis of sleep

NREM (stage 1) Disappearance of alpha rhythm and replacement by theta waves,

sharply V wave and POSTS(positive occipital sharp transient of sleep) slow horizontal rolling eye movement.

Physiological basis of sleep

NREM (stage 2) K-complexes (high amplitude, biphasic waves , at least 0.5 s) Sleep spindles (chains of rhythmic 12-14 Hz activity with

duration of 0.5 to 2-3 S)

Physiological basis of sleep

NREM (stage 3 – 4) Slow waves sleep High amplitude(>75 mic V) delta with frequency of 2 Hz

or less.

Physiological basis of sleep

REM sleep• The state of internal arousal• Classified as tonic and phasic• Poikilothermia • Dreaming • 90-120 min after sleep onset (20-25% of sleep)

Physiological basis of sleep

REM sleep• Low amplitude, mixed frequency theta waves mixed with alpha

waves.• Rapid eye movement• Lowest tone in EMG

Polysomnography

Polysomnography

Variable monitoring during PSG Neurological

EEG

EOG

EMG (sub mental & ant. Tibial) Respiratory

airflow

respiratory effort

oxyhemoglobin saturation

upper airway sound Cardiac

ECG

Sleepiness

Quantitative measures of sleepiness and alertness• Sleepiness scale

Epworth sleepiness scale

Standford sleepiness scale

Visual analog scale• Multiple sleep latency test (MSLT)• Maintenance of wakefulness test (MWT)• Pupillometry• Performance test

Epworth Sleepiness Scale ) اينكه نه ؟ بزنيد چرت يا و برويد خواب به كه دارد احتمال چقدر ، زير موقعيتهاي در گيري قرار صورت در

. اگربعضي ) حتي حاضراست درحال شما زندگي روش به مربوط قسمت اين بكنيد خستگي احساس فقطاثري چه حاالتي چنين كه دريابيد ، مشابه كارهاي به باتوجه كنيد ،سعي ايد نداده انجام < اخيرا مواردرا ازاين

؟ گذاشت خواهد شما رويكردن 1- مطالعه و نشستنزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنمتلويزيون 2- تماشايزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنمباكسيصحبتكردن 3- و نشستنزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنممحيطينشستن 4- در آرام ، ناهار از بعدزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنم-5) سخنراني ) جلسة يا سينما عمومينشستن مكان يك در فعاليت بدونزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنمتوقفباشيد .6- بدون يكساعت طوريكه به اتومبيل يك در مسافر عنوان بهزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنمرا ) 7- كار اين اجازة و بوده مناسب محيط طوريكه به استراحت براي كشيدن دراز ظهر از بعد

) باشيد داشتهزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنممتوقفاست 8- ترافيك در دقايقي براي كه هنگامي نقليه وسيلة يك درزنم 0- نمي بزنم- 1هرگزچرت چرت كه دارد كمي زنم- 2احتمال مي >چرت مي- 3معموال چرت اوقات اغلب

زنم

. با سؤاالت از امده بدست امتياز ميزان است شده مشخص پاسخ هر كنار در سؤال هر از فرد امتياز ميزان. ميگردد مشخص نهايي امتياز و شده زده جمع هم

Epworth sleepiness scale (ESS)

• The commonest scale to assess sleepiness• ESS correlates with the intensity of

psychological symptoms• Higher in woman than man• Useful for monitoring of response to treatment• Upper normal limit = 10-11 points• Excessive daytime sleepiness = ESS> 13

Multiple Sleep Latency Test

• The objective assessment of sleepiness and alertness (tendency to fall asleep)

• MSLT often contribute to diagnosis but is usually not sufficient .

• MSLT can help to determine the clinical significance of sleep disorder or to assess response to treatment .

• MSLT is not valid in children (<8 y)

MSLT Pre test conditions:• A nocturnal PSG is preceded.• The test is sensitive to sleep deprivation so adequate

total sleep for a week is needed (actigraphy is useful)• Sleep log (diary) of amount and pattern of sleep

during 2weeks before MSLT• Physical exercise not be performed on the day of test• No smoking and caffeine for at least 30 min before

test

MSLT

• Drug such as stimulants, hypnotics, major tranquillizers, opioids should be discontinued at least 2 weeks

• Fluoxetine (long half life) should be stopped earlier.• If stopping is impossible it is better not to perform

MSLT at all. (not interpretable)• Heavy caffeine use should be slowly weaned a week

before test.• Urine drug screen should be obtain.

MSLT

Performance of the MSLT• The patient is given 4-5 nap opportunities (20 min)

to sleep over the day, usually at 2 hours intervals (8am-10am-12 noon-2pm-4pm)

• The patient lies in bed in a dark quiet room with comfortable cloths and no shoes.

MSLT

Standard terms:• Sleep latency: the time from light out to the first

epoch of any stage of sleep (max= 20 min)• REM latency: the time from first sleep to the first

epoch of REM sleep (max= 15 min)• Mean sleep latency: average of sleep latencies

MSLT

Interpretation of SMLT:• Normal MSLT= mean sleep latency >15 min and

0-1 REM sleep• Mild sleepiness = mean sleep latency of 10-15 min• Moderate Sleepiness= mean sleep latency of 5-10

min• Severe (pathologic) sleepiness= mean sleep latency

<5 min

MSLT REPORT Patient Name: Mosleh, Sadegh Height: 178 Cm. Sex: Male B.M.I. 26 D.O.B. 01-01-1948 Study Date: 11-19-2008 Age: 60 Subject Code: 25 Weight: 81 Kg.

Nap 1 Nap 2 Nap 3 Nap 4 Nap 5 Means

Start Time 08:52:24 11:14:01 01:00:29 14:48:11 No Nap

End Time 09:17:11 11:37:11 01:27:25 15:09:11 No Nap Recording Length 25 23 26.9 21 No Nap 23.9

Total Sleep Time 13 No Sleep 20.2 5 No Nap 9.5

Onset to Sleep 5 20.0 5.2 4 No Nap 8.5 Onset to REM Sleep No REM No REM No REM No REM No Nap No REM

MovementStage 4Stage 3Stage 2Stage 1

RemWake

09:00 10:00 11:00 12:00 13:00 14:00 15:00

Hyp

nogr

am

Maintenance of Wakefulness Test (MWT)

• The patient is asked to remain awake as long as possible.

• MWT is not diagnostic test for degree of sleepiness but rather a test of ability to remain awake

MWT

MWT is used:

1) To assess fitness to fly a plane or drive a truck or bus.

2) To assess a pilots permission to regain their license before treating for sleep apnea. (by United State Federal Aviation Administration)

3) To assess efficacy of treatment for hypersomnia.

4) To assess narcoleptic patient who complain of tiredness, despite of high quantities of stimulant medication.

MWT

Performance of MWT• Nocturnal PSG before MWT is optional.• Four trials at 2 hours intervals to remain awake

with eye open.• The patient is sitting semireclining in bed, with

back and head supported by a bed rest cushion.• A night-light (7.5 W) behind the patient head.• Two variant of test: 20 min & 40 min

MWT

Interpretation of MWT:• Mean MWT latencies do not correlate with total

sleep time (sleep deprivation does not affect the result)

• The cut-off point for alertness in 20 min version is 11 min & in 40 min version is 22.5 min (15 percentile)

Actigraphy • A small devices as like as wristwatch.• It is worn during both the night and day.

Actigraphy

Sleep and Performance

• Sustained behavioral wakefulness (90 hours) resulted in:

• decreased :

sensory acuity

reaction time

motor speed

memory• occurrence of uncontrollable napping and semi-wake

dream

sleepiness is modulated by :

A circadian rhythm The stronger nadir occurs at night, between 10 P.M.

and 8 A.M., peaking around 4 A.M. The second occurs between 2 P.M. and 4 P.M.

The longer we have been awake (the fewer hours we have slept), the more our drive for sleep increases

SLEEP DISORDERS

Sleep disorders - overview

There are more than 100 different sleeping and waking disorders. They can be grouped into four main categories:• Problems falling and staying asleep (insomnia)• Problems staying awake (excessive daytime sleepiness)• Problems sticking to a regular sleep schedule (sleep

rhythm problem)• Unusual behaviors during sleep (sleep-disruptive

behaviors)

Sleep disorders - classification

1( Dyssomnias :difficulty to get to sleep, or to remain sleeping.

2( Parasomnias : abnormal movements, behaviors, emotions, perceptions, and dreams that occur while falling asleep, sleeping, between sleep stages, or during arousal from sleep

3( Medical or psychiatric conditions that may produce sleep disorders

4( Sleeping sickness : a parasitic disease which can be transmitted by the Tsetse fly.

Insomnia

Insomnia

• Defined as the subjective sense that sleep is difficult to initiate or maintain or that sleep itself is non refreshing.

• About one third of the adult population experiences insomnia (nearly 10% as a chronic problem)

• They sufferer from daytime consequences similar to those associated with chronic sleep deprivation, such as fatigue, performance decrements, and mood disturbances .

Insomnia (Pathophysiology)

Precipitating factor (5 Ps): • Physical• Psychological• Psychiatric• Pharmacologic• Physiologic

Insomnia (Diagnosis)

• NOTE Insomnia is a symptom and not a disorder itself• Careful evaluation of potential underlying causes or

contributors• The principal diagnostic tools are subjective assessment

of sleep quantity and quality. (Diaries of sleep-wake activity)

• Objective sleep-monitoring technology: polysomnography & actigraphy (a wrist-worn motion detector)

Insomnia (Treatment)

• You should seek help if your insomnia has become a pattern, or if you often feel fatigued or unrefreshed during the day and it interferes with your daily life.

Insomnia (Treatment)

General :• Correction of the underlying cause (medical or

psychiatric issues).• Simple changes in routine, living situation, and food

intake• Education of mechanics of sleep (sleep promoting

and interfering behaviors- Relaxation training, stimulus control, sleep restriction, and cognitive behavioral therapy are some examples.)

Insomnia (Treatment)

Specific :• Transient insomnia (a few days to a couple of weeks) :

sedatives/hypnotics like shorter acting benzodiazepines, non benzodiazepine receptor agonists, and the new melatonin receptor agonists

• Short-term insomnia (several weeks to a month): sedative/hypnotic therapy for the short term, behavioral therapies and education

• Long-term or chronic insomnia (months to years): - behavioral treatments such as sleep restriction, cognitive

therapy, relaxation therapies, stimulus control, and biofeedback (effective during a 6-8 week program)

-Sedative/hypnotic medication as reinforcement

Insomnia (Treatment)

• Over 40% of people with complaints of insomnia have been reported to self-medicate with over-the-counter products and/or alcohol

• Alcohol has sedating nature but it causes fragmented sleep and profound REM sleep rebound and nightmares and rapid tolerance

• Natural products, such as L-tryptophan, melatonin and valerian root

Obstructive Sleep Apnea

Obstructive Sleep Apnea

• The most common disorder resulting in daytime sleepiness among adult workers

• OSAS is characterized by repetitive brief periods (10 to 60 S) of cessation of airflow during sleep, which result in brief arousals.

• The subtle form of OSAS is upper airway resistance syndrome (UARS)

• Daytime consequences include excessive sleepiness, cardiovascular changes, and cognitive deficits

OSAS (Pathophysiology)

Blockage of the upper airway is result of:• Changes in muscle tone• Redundant tissue• Enlarged tonsils and adenoids• Anatomically small airway passage• Changes in the arousal threshold occurring

with the ingestion of alcohol or sedating drugs.

OSAS (Symptoms)

• Typical symptoms of untreated OSAS and UARS include loud, sporadic snoring, excessive sleepiness, and restless sleep.

• Consequences: Cardiovascular (hypertension, arrhythmia, and strokes) loss of memory, irritability, depression, and impotence.

OSAS (Treatment)

• Continuous positive airways pressure device )CPAP(• Surgical repairs of the upper airway

uvulopalatopharyngoplasty (UPPP)• Laser-assisted UPPP (LAUP)• Dental devices designed to increase airway space by

extending the mandible• Behavioral techniques such as weight loss or position

changes during sleep

Narcolepsy

Narcolepsy

• Debilitating lifelong CNS disorder of excessive daytime sleepiness affecting 0.03% to 0.05% of the worldwide population

• Onset peaking in the second decade but continuing into the fifth decade of life

Narcolepsy

Pentad of primary symptoms (not all must be present for diagnosis).

• severe sleepiness (all persons)• Cataplexy (65% to 90%)• hypnagogic hallucinations (30% to 60%) • sleep paralysis (30% to 60%) • fragmented nocturnal sleep (50% )

Narcolepsy (Pathophysiology)

• An autoimmune process that attacks the hypocretin (orexin) system in the hypothalamus.

• A strong association with HLA class II • Strong genetic involvement (not conclusive or

necessary for the diagnosis of narcolepsy)

Narcolepsy (Diagnosis)

• Nocturnal polysomnograms followed by a Multiple Sleep Latency Testing (MSLT)

• Positive MSLT, after a night in which other sleep disorders are excluded, requires a mean latency to sleep of under 8 minutes with at least two REM-onset naps

• Although cataplexy may be a pathognomonic but polysomnography is necessary.

• Currently, hypocretin-1 levels of cerebral spinal fluid

Narcolepsy (Treatment)

Treatment is very individualized and depends on the clinician's expectations for outcome as well as the patient's and family's goals

Therapy involves the combination of pharmacologic and behavioral techniques

Short (20 minutes) daytime naps.Regular sleep hours and daytime schedules

Antidepressant drugs (TCA and SSRI), improve the REM sleep related symptoms of cataplexy, hallucinations, and sleep paralysis

gamma-hydroxybutyrate (sodium oxybate) for cataplexy. and daytime sleepiness

Shift-work Sleep Disorder

• SWSD is characterized by complaints of insomnia or excessive sleepiness related to work hours scheduled during normal sleep periods and occurs despite optimizing the sleep environment.

• The FDA has recently approved modafinil (Provigil) for use as a wake promoter in this disorder

Impact of Insomnia on the Workplace

• Decrease peak performance at positions that require heightened vigilance for long time.

• The concerned about the impact of hypnotic therapy and any sedating effects.

• Any sleep loss may impact the general health of the worker through changes caused to immune function and the stress response.

Impact of Narcolepsy on the Workplace

The global impact of narcolepsy on the workplace will depend, on the person's age at symptom onset and diagnosis

Certain jobs for which a person with narcolepsy is unfit.

1-occupations requiring long periods of driving 2-monotonous attention to critical dials and gaugesIf cataplexy is uncontrolled, occupations that offer

episodes of intense emotional excitement should be avoided

Impact of OSAS on the Workplace

• The impact of untreated OSAS on the workplace can be serious due to the effects of unrecognized sleep loss

• High risk job :commercial driver who is male, middle aged, and overweight/obese

Sleep hygiene

1. Power Down• The soft blue glow from a cell phone, tablet, or digital clock

on your bedside table may hurt your sleep.• Tip: Turn off TVs, computers, and other blue-light sources

an hour before you go to bed. Cover any displays you can't shut off.

2. Nix Naps• You’ll rest better at night. But if you have to snooze while

the sun's up, keep it to 20 minutes or less. Nap in the early part of the day.

• Tip: Overcome an afternoon energy slump with a short walk, a glass of ice water, or a phone call with a friend.

3. Block Your Clock• Do you glance at it several times a night? That can make

your mind race with thoughts about the day to come, which can keep you awake .

• Tip: Put your alarm clock in a drawer, under your bed, or turn it away from view.

4. Try a Leg Pillow for Back Pain• Your lower back may not hurt enough to wake you up,

but mild pain can disturb the deep, restful stages of sleep. Put a pillow between your legs to align your hips better and stress your low back less.

• Tip: Do you sleep on your back? Tuck a pillow under your knees to ease pain.

5. Put Your Neck in 'Neutral'• Blame your pillow if you wake up tired with a stiff neck. It

should be just the right size -- not too fat and not too flat -- to support the natural curve of your neck when you're resting on your back. Do you sleep on your side? Line your nose up with the center of your body. Don’t snooze on your stomach. It twists your neck.

• Tip: Use good posture before bed, too. Don't crane your neck to watch TV.

6. Seal Your Mattress• Sneezes, sniffles, and itchiness from allergies can lead

to lousy shut-eye. Your mattress may hold the cause. Over time, it can fill with mold, dust mite droppings, and other allergy triggers. Seal your mattress, box springs, and pillows to avoid them.

• Tip: Air-tight, plastic, dust-proof covers work best.

7. Save Your Bed for Sleep • Your bedroom should feel relaxing. Don’t sit in bed and

work, surf the Internet, or watch TV.• Tip: The best sleep temperature for most people is

between 20-22 degrees.

8. Set Your Body Clock• Go to sleep and wake up at roughly the same time every

day, even on weekends. This routine will get your brain and body used to being on a healthy snooze-wake schedule. In time, you'll be able to nod off quickly and rest soundly through the night.

• Tip: Get out in bright light for 5 to 30 minutes as soon as you get out of bed. Light tells your body to get going!

9. Look for Hidden Caffeine• Coffee in the morning is fine for most people. But as soon

as the clock strikes noon, avoid caffeine in foods and drinks.  Even small amounts found in chocolate can affect your Zzzz's later that night.

• Tip: Read labels. Some pain relievers and weight loss pills contain caffeine.

10. Work Out Wisely• Regular exercise helps you sleep better -- as long as you

don’t get it in too close to bedtime. A post-workout burst of energy can keep you awake. Aim to finish any vigorous exercise 3 to 4 hours before you head to bed. 

• Tip: Gentle mind-body exercises, like yoga or tai chi, are great to do just before you hit the sack.

11. Eat Right at Night• Don’t eat heavy foods and big meals too late. They

overload your digestive system, which affects how well you sleep. Have a light evening snack of cereal with milk or crackers and cheese instead.

• Tip: Finish eating at least an hour before bed.

12. Rethink Your Drink• Alcohol can make you sleepy at bedtime, but beware.

After its initial effects wear off, it will make you wake up more often overnight.

• Tip: Warm milk or chamomile tea are better choices.

13. Watch What Time You Sip• Want to lower your odds of needing nighttime trips to the

bathroom? Don’t drink anything in the last 2 hours before bed. If you have to get up at night, it can be hard to get back to sleep quickly.

• Tip: Keep a nightlight in the bathroom to minimize bright light.

14. Lower the Lights• Dim them around your home 2 to 3 hours before

bedtime. Lower light levels signal your brain to make melatonin, the hormone that brings on sleep.

• Tip: Use a 15-watt bulb if you read in the last hour before bed.

15. Hush Noise• Faucet drips, nearby traffic, or a loud dog can chip away

at your sleep. And if you're a parent, you might be all too aware of noises at night long after your children have outgrown their cribs.

• Tip: Use a fan, an air-conditioner, or a white noise app or machine. You can also try ear plugs.

16. Turn Down Tobacco• Nicotine is a stimulant, just like caffeine. Tobacco can

keep you from falling asleep and make insomnia worse.• Tip: Many people try several times before they kick the

habit. Ask your doctor for help.

17. Beds Are for People• A cat's or a dog's night moves can cut your sleep short. They can

also bring allergy triggers like fleas, fur, dander, and pollen into your bed. 

• Tip: Ask your vet or animal trainer how you can teach your pet to snooze happily in its own bed.

18. Free Your Mind• Put aside any work, touchy discussions, or complicated decisions 2

to 3 hours before bed. It takes time to turn off the "noise" of the day. If you’ve still got a lot on your mind, jot it down and let go for the night. Then, about an hour before you hit the sack, read something calming, meditate, listen to quiet music, or take a warm bath.

• Tip: Even 10 minutes of relaxation makes a difference.

19. Use Caution with Sleeping Pills• Some sleep medicines can become habit-forming, and

they may have side effects. Ideally, pills should be a short-term solution while you make lifestyle changes for better Zzzz's. Ask your doctor what’s OK.

20. Know When to See Your Doctor• Let her know if your sleeplessness lasts for a month or

more. She can check to see if a health condition -- such as acid reflux, arthritis, asthma, or depression -- or a medicine you take is part of the problem.

Thanks for your attention