Sleep, sleep disorders

Professor Yasser Metwally

Each of us will spend about 27 years of our lifetime sleeping…..

…..And 1/3 part of the population has sleep disorder

About the sleep…

„Why we sleep remains one of nature’s greatest mysteries”(MG Frank, The function of sleep, 2006)

Somatic theories of sleep functionNeural metabolic theories: detoxification and

regenerationCognitive theories of sleep function: learning

and brain development

Regulation of sleep

Cirkadian timing: lasts about 24 hours• Hypothalamus

• Suprachiasmatic nucleus

• Pituitary gland: melatonin

Ultradian timing: lasts less than 24 hours • Prepontin nuclei• Raphe nuclei• L. coeruleus

Normal human sleepSleep cycle – occurs about every 90 minutes, approximately 4-6 cycles occur per major sleep episodeMicroarousal

1. NREM (70-80%) • slow wave sleep• heart rate, BP, breathing ↓• body temperature, muscle tone ↓

2. REM (20-25%) • rapid eye movement, paradox, fast wave sleep• heart rate, BP, breathing ↑, metabolic rate ↑ • dreaming, erection• muscleatonia, BUT: myoclonus!

NREM

I. stage (3-8%) ~ drowsiness, sleepiness EEG: α-activity, muscle tone, eye movement ↓, myoclonus!

II. stage (45-55%) ~ EEG: K-complexes, sleep spindles, no eye movement

III. stage (5-10%) EEG: delta waves

IV. stage (15-20%) slow wave sleep

1. Tonic stage (desyncronized EEG ~ low voltage, frequency ↑, muscle atonia)

2. Phasic stage (rapid eye movements ~ fast, saccadic eye movements ~, irregular breathing, heart rate ↑, myoclonus, apnea, hyperpnea, dreaming!!!)

REM

Sleep disorders

Polysomnography

• multiparametric monitoring during 1 sleep period (1 night)

• EEG• Electrooculogram• EMG• ECG• Respiratory effort

• SpO2

• Body position• Snoring

More than 80 sleep disorders are known (International Classification of Sleep Disorders, 2nd Edition

American Academy of Sleep Medicine, 2005)

I. Insomnias (33%)

II. Sleep related breathing disorders (1,4-40%)

III. Hypersomnias (0,3-16,3%)

IV. Cirkadian rhythm sleep disorders

V. Parasomnia

VI. Sleep related movement disorders

VII. Isolated symptoms, normal variants

VIII. Other sleep disorders

Traditional classification of sleep disorders

• Dyssomnias: abnormalities in the quantity, quality or timing of sleep. They are associated with difficulty initiating or maintaining the sleep or daytime sleepiness.

• Parasomnias: abnormal behavioral or physiological events occurring during sleep but don’t involve the sleep mechanisms per se.

I. Insomnias

• Difficulty in initiating sleep or in staying asleep or waking up earlier

• Nonrefreshing, nonrestorative sleep

• Fatigue, concentration or memory impairment

• Mood disturbances, motivation, initiative reduction

• Daytime sleepiness

• Tension headache

I. Insomnias

• Prevalence: 33%• Accompanied with daytime consequences:

10%• Last less than 1 month: 4% (transient

insomnia)• Last more than 1 year: 85% (persistent

insomnia)• Male:female = 1:1.4• Increase with age: above 65 years: 50%

I. Insomnias

1. Primary (idiopathic)2. Secunder

1. Inadequate sleep hygiene (10%)2. Paradoxical insomnia (10%)3. Insomnia due to mental disorder (30-40%)4. Psychophysiological insomnia (15%)5. Insomnia due to drug or substance6. Insomnia due to medical conditions 7. Sunday night insomnia

Treatment

• Treating the medical or psychiatric conditions (sec. insomnias)

• Nonpharmacologic: – behavioral treatments: normalizing the

circadian rhythm – sleep hygiene– cognitive behavior therapy– sleep restriction therapy

• Pharmacologic treatment

Pharmacologic treatment

Benzodiazepines1. midazolam, triazolam ~ rebound

insomnia2. cinolazepam, quazepam

3. brotizolam, temazepam

4. nitrazepam ~ drowsiness

Pharmacologic treatment

Selective GABAA agonists: nonbenzodiazepines

– no rebound insomnia– zolpidem, zopiclon

Melatonin receptor agonist– ramelteon

II. Sleep related breathing disorders (International Classification of Sleep Disorders, 2nd Edition

American Academy of Sleep Medicine, 2005)

3. Sleep related hypoventilation/hypoxemia

1.

2.

Apnea-hypopnea index (AHI)

- Numbers of apneas and hypopneas/ 1 sleeping hour

Severity of sleep related breathing disorders:

- Normal: AHI<5/h- Mild: AHI: 5-15/h- Moderate: AHI:16-30/h- Sever: AHI>30/h

Sleep, 1999:22:667-89.

OSAHS: symptoms

Daily• Excessive daytime

sleepiness• Unrefreshing sleep• Memory disturbances• Morning headache• Depression• Decreased libido• Stomach ache

Nightly• snoring• apneas• choking, gasping• arousals• sweating• dry mouth• palpitation• nycturia

OSAHS: diagnostic criteria

(1. or 2.) and 3.

AASM, Sleep, 1999:22:667-89.

Risk factors of OSAHS

• Obesitas• Age• Male gender• Pozitive family history of OSAHS• Alcohol consumption before bedtime• Race• Smoking• Sedatives• Craniofacial anomalies• Hypothyroidism, acromegaly

Treatment of bening snoring

• Weight loss, alcohol withdrawal

• Position training

• Nasal, pharyngeal surgery (UPPP)

• Oral appliances

Treatment of OSAHS: nasal CPAP

IV. Cirkadian rhythm sleep disorders• Primary

– Delayed sleep phase type – Advanced sleep phase type – Irregular sleep phase type

• Secondary– Jet lag type– Shift work type

• Treatment – Sleep hygiena – Cronotherapy– Light therapy– Melatonin, zolpidem

V. Parasomnias

1. In NREM1. Myoclonus

2. Enuresis nocturna

3. Pavor nocturnus, night terrors

4. Sleep walking - somnambulism

5. Bruxism

2. In REM1. Nightmares

2. REM sleep behavior disorder

VI. Sleep related movement disorders

• Restless legs syndroma– Therapy: dopamin agonists

• Periodic limb movement disorder

• Sleep related leg cramps

• Sleep related rhythmic movement disorder