Sleep Disorders

Question 1

Sleep

Answer 1

A normal, reversible, recurring behavioral state of disengagement and unresponsiveness to the environment that is characterized by typical changes in the electroencephalogram

Question 2

Function of sleep?

Answer 2

Physical restoration, optimizing of waking neurocognitive and emotional function, learning and emotional processing, health and survival

Question 3

Stages of sleep and associated EEG changes

Answer 3

Awake: Alpha waves (8-14 Hz)
Stage 1: Light sleep, less alpha activity, theta waves (4-7 hz)
Stage 2: Most sleep occurs in stage 2 (40-55%), theta activity, sleep spindles and K complexes
Stage 3+4: Deeper sleep, delta waves, limited muscle activity
REM

Question 4

REM sleep

Answer 4

20-25% of sleep occurs here, 4-6 episodes per night, EEG appears similar to stage 1 sleep. Dreaming, increased HR. , rapid shallow breathing

Question 5

When do stage 3 and 4 sleep occur?

Answer 5

In the first half of the night. REM increases as night progresses

Question 6

Sleep latency

Answer 6

The time from lights out to first NREM stage 1: usually 10-20 minutes

Question 7

REM latency

Answer 7

Time from sleep onset to first REM, usually 90-100 minutes

Question 8

Sleep efficiency

Answer 8

Amount of sleep/total time in bed *100

Question 9

Aging and sleep

Answer 9

Less sleep needed, stage 3-4 sleep gradually diminishes. Increased sleep latency, nocturnal awakenings, more stage 1 sleep. Decreased Delta sleep, decreased REM, decreased sleep efficiency

Question 10

Ways of measuring sleep

Answer 10

Epworth sleepiness scale
Polysomnography (EEG, Electrooculography, electromyography)
Multiple sleep latency test

Question 11

Primary sleep disorders

Answer 11

Dyssomias: Too much/too little sleep
Parasomnias: Abnormal behaviors or physiologic events that arise during specific sleep stages or during transitions between wakefulness and sleep

Question 12

Sleep Apnea

Answer 12

Repetitive episodes of complete or partial cessation of air flow during sleep that often result in oxygen desaturation and terminal with brief arousals.

Can be obstructive or central

Question 13

Apnea vs hypopnea

Answer 13

Apnea is cessation of breathing >10 seconds. Hypopnea is reduction in airflow > 10 seconds

Question 14

Consequences of obstructive sleep apnea

Answer 14

Right heart CHF, stroke, hypertension, increase in all mortality. Occurs in fat males

Question 15

What causes central sleep apnea?

Answer 15

Lower brainstem lesions

Question 16

Narcolepsy

Answer 16

Frequent attacks of irresistible daytime sleepiness. Can occur with cataplexy, sleep paralysis, hypnogogia. Often have normal polysomnogram. IMMEDIATE ONSET REM.

Question 17

Cause of narcolepsy

Answer 17

Dysfunction of hypothalamic neuropeptide orexin

Question 18

Ondine’s Curse

Answer 18

Total loss of automatic breathing, especially during sleep

Question 19

Kleine-Levin Syndrome

Answer 19

Repeated episodes of excessive daytime somnolence, coupled with hyperphagia, aggressiveness, and hypersexuality.

Question 20

Circadian Rhythm Disorders

Answer 20

A misalignment of the desired sleep wake schedule and the endogenous circadian rhythm related propensity for sleeping and waking.

Question 21

Non-REM sleep Parasomnia vs REM sleep parasomnia

Answer 21

NRSP: Night Terrors/Sleep walking, observed in young children, usually during the first two hours of sleep (DELTA). No dreaming, followed by confusion.

REMSP: Nightmare disorder/REM behavior disorder. Occurs during REM sleep. Vivid dream recall, no confusion post-attack. Occurs in older men.

Question 22

Sleep Hygiene

Answer 22

Good pre-bedtime habits