sleep-wake disorders

Question 1

2 important sleep states

Answer 1

1. slow wave sleep.
2. REM sleep.

Question 2

insomnia

Answer 2

predominant complaint of dissatisfaction with sleep quantity or quality, with at least 1 of the following:
1. difficulty initiating/maintaining sleep.
2. early morning awakening with inability to return to sleep.

12 month prevalence: 6%. lifetime prevalence: 10%.

etiological: delayed body temperature rhythm, drug use, hyperthyroidism, environmental issues, recurrent napping, association between bed and wakefulness cues, dysfunctional beliefs about sleep.

treatment: sleeping pills, melatonin, antithyroid medications, elimination of environmental issues or naps, behavioural therapy for extinction of wakefulness cues, cognitive therapy for beliefs.

Question 3

hypersomnolence disorder (hypersomnia, hyperpathic hypersomnia)

Answer 3

excessive sleepiness despite 7 hours of sleep with at least one of the following:
1. recurrent periods or lapses of sleep during the day.
2. can sleep for more than 9 hours without feeling refreshed.
3. difficulty being fully awake after abrupt awakening.

three subtypes:
1. acute (<1 month).
2. subacute (1-3 months).
3. persistent (3+ months).

naps are not restorative.

Question 4

narcolepsy

Answer 4

recurrent episodes of need to sleep, lapsing into sleep, and napping in same day, plus one of the following:
1. cataplexy (losing muscle support while conscious).
2. hypocretin/cretin hormone deficiency.
3. nocturnal REM sleep latency of less than 15 minutes, average sleep latency of less than 8 minutes, and more than 2 sleep onset REM periods.

Question 5

sleep inertia

Answer 5

difficulty being awake (symptom of hypersomnolence disorder).

Question 6

hypersomnia and narcolepsy etiological factors and treatment options

Answer 6

etiological: genetic, orexin deficiency, histamine (wake promoting) system, hypothyroidism, used as coping mechanism (?).

treatment: modafinil (stimulant)/amphetamines, antidepressants (cataplexy), psychoeducation, coping strategies, adjustment to life circumstances.

Question 7

circadian rhythm disorders

Answer 7

sleep disruption due to alteration of circadian rhythm/misalignment between endogenous circadian rhythm and person’s sleep-wake schedule for three or more months. excessive sleep, insomnia, or both. 4 subtypes:
1. delayed sleep.
2. advanced sleep.
3. non 24 hour.
4. shift work.

etiological: suprachiasmatic nucleus (changes sleep-wake schedule in response to light), melatonin, changing work schedules.

treatment: melatonin, phase delaying, exposure to sunlight or bright light therapy, changing expectations regarding employment.