Therapeutics - Insomnia

Question 1

What is the aetiology of insomnia?

Answer 1

Inability to ini/maintain sleep
Assoc w daytime problems

Question 2

Describe the physiology of sleep

Answer 2

24h
- Resetting of internal clocl by cues (day light)

Hormonal
- Melatonin secre increased during sleep and suppressed by bright light

Neurotransm
- Sleep promoting: GABA
- Wakefulness promoting: NE, DA, ACh, Histamine, orexin (also helps w appetite)

Non rapid eye movement sleep (nREM)
- 75% of total sleep time
- Low HR, BP, RR
- Stage 1: light sleep 5% TST (ini of sleep over 15-30min)
- Stage 2: deep sleep 45% TST
- Stage 3&4: slower EEG, delta sleep, 25% TST = RESTORATIVE SLEEP, release GH, restore protein synth, wound healing, immune fn, muscles relax

Rapid eye movement sleep (REM)
- 25% TST, Q90min
- a/w dreaming, memory consolidation, sensorimotor dev, nocturnal erections
- poikilothermic (cold blooded)
- HR, RR, BP can fluctuate

Cyclical 4-6 cycles/night, 70-120min per cycle
Oscillate bet REM and NREM

Question 3

What is the recommended amt of sleep?

Answer 3

18-65y.o.: 7-8h
>65y.o.: Min 8h

Question 4

What are the risk factors of insomnia?

Answer 4

Daytime problems
Anxiety, depression

Question 5

What are the signs and symptoms of insomnia?

Answer 5

A. Primary complaint of unsatisfying sleep quantity or quality, w presence of 1 or more of following
1. Difficulty w sleep ini
2. Difficulty w sleep maintenance
3. Early morning awakening

B. Sleep complaint assoc w social, occupational, academic, edu, behavioural or fnal distress or impairment
C. Sleep complaint occurs at least 3 nights per week and has been present for at least 3mo
D. Sleep difficulties happen even w ample opportunity to sleep
E. Sleep complaint is not attrubuted to or explained by another sleep-wake disorder, the adverse effect of a med or sub or co-existing psychiatric illness or medical condition
F. DSM-5 specifications on duration
- Episodic: 1mo-<3mo
- Persistent: lasting >=3mo
-Recurrent: >= 2ep within year

Excessive daytime sleepiness
Impaired concentration/memory
Fatigue

Question 6

What are the differential Dx associated w insomnia?

Answer 6

Asthma
Cough at night
Painful condition that wakes/disturbs sleep e.g. gout
Itchy skin
Wake up gasping for air (sleep apnea, orthopnea)
Wake up from shock due to nightmare

Question 7

What are the tests we may use for insomnia?

Answer 7

Objective
Polysomnography - comprehensive recording of EEG, electroculogram, electromyogram, SpO2, RR, HR

Subjective
Quality of sleep e.g. refreshing or otherwise
Excessive daytime sleepiness (EDS)

Question 8

What are the classifications for insomnia?

Answer 8

Transient <1week
Acute <4weeks
Chronic >4weeks

Question 9

What is the non-pharm recommendation for insomnia?

Answer 9

CBT
Sleep hygiene
Relaxation therapy
Sleep restriction thera
Stimulus control thera

Question 10

Discuss sleep hygiene strategies?

Answer 10

Avoid caffeine containing pdts, nicotine, alc esp later in day(after 5pm)
Avoid drinking fluids after dinner to prevent freq night time urination
Avoid places that make u rlly active after 5pm
Only use bed for sleeping. If you want to relax, sit on a chair.
Do not watch television on the bed.
Avoid execise and food 2-3h before sleep.
Create atmosphere conducive for sleep
Get up same time everyday incl weekends. Use alarm clock.
Avoid taking daytime naps. If take, do so before 3pm, limit to 1h.
Pursue regular physical activities like walking or gardening but avoid vigorous exercise too close to bed time.

Question 11

Describe the principles of pharmacological management.

Answer 11

Benzodiazepines
Z-hypnotics
Antihistamines
Melatonin (preferred if >55y.o.)
Lemborexant

Short term for 7-10d (1-2 weeks, up to 2-4 weeks), Benzos limit to 2 weeks

Question 12

Differentiate anxiolytics, hypnotics and neuroleptics.

Answer 12

Anxiolytics are taken for a patient to sleep at night time

Hypnotics are given for a patient to sleep at day time

Antipsychotics = neuroleptics, tranquilise without impairing consciousness