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insomnia & sleep disturbance

sleep disturbance may be primary insomnia, circadian disruption, obstructive sleep apnoea, restless legs, depression, anxiety, mania, ptsd, substance-related, medication-induced, or a symptom of medical disease — cbt-i and diagnosis of the driver are central

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About This Page

This is a clinician-written, evidence-based guide aligned to the MCC Examination Objectives. It is structured by clinical presentation — the way the MCCQE tests and the way patients actually present. Management reflects current Canadian guidelines (CMA, CFPC, CPS). Always cross-reference with institutional protocols and clinical judgment.

The Bottom Line

  • Insomnia is not automatically a hypnotic deficiency: identify depression, anxiety, mania, PTSD, pain, OSA, restless legs, circadian disruption, substances, and medications
  • Red flags include decreased need for sleep with increased energy, suicidal depression, psychosis, severe OSA symptoms, parasomnia injuries, and withdrawal states
  • First-line chronic insomnia treatment is CBT-I: stimulus control, sleep restriction, cognitive therapy, relaxation, and sleep hygiene as an adjunct
  • Hypnotics should be short-term, lowest effective dose, and avoided or used cautiously in older adults, pregnancy, OSA, substance use disorder, falls risk, and concurrent opioids/alcohol
  • Use a sleep diary and screen for snoring/witnessed apnoeas, restless legs, shift work, caffeine/cannabis/alcohol, and medication causes

Approach to the Presentation

The MCCQE1 framing of insomnia is broad: difficulty initiating sleep, maintaining sleep, early morning waking, non-restorative sleep, hypersomnia, parasomnias, circadian disorders, and sleep-related breathing disorders can all present as sleep disturbance. Characterise timing, duration, schedule, naps, shift work, screen use, caffeine, alcohol, cannabis, stimulants, withdrawal, pain, nocturia, menopause symptoms, mood, anxiety, trauma, and functional impairment. Ask specifically about snoring, witnessed apnoeas, choking, morning headaches, restless legs, dream enactment, nightmares, and decreased need for sleep.
Differential Diagnosis
diagnosislikelihoodkey featuresdistinguishing test
Mania / hypomaniamust-not-missReduced need for sleep without fatigue, increased energy, pressured speech, racing thoughts, impulsivity, irritability, grandiosityMood history, collateral, mental status exam
Major depression with suicide riskmust-not-missEarly morning wakening, low mood, anhedonia, guilt, appetite change, psychomotor change, suicidal ideationDepression and suicide risk assessment; PHQ-9 as monitoring tool
Alcohol/benzodiazepine/opioid withdrawalmust-not-missInsomnia with tremor, diaphoresis, anxiety, tachycardia, hallucinations, diarrhoea, mydriasis, piloerectionSubstance timeline, CIWA-Ar/COWS, medication records
Obstructive sleep apnoeacommonLoud snoring, witnessed apnoeas, choking/gasping, daytime sleepiness, morning headaches, hypertension, obesity or craniofacial riskSTOP-Bang + home sleep apnoea test or polysomnography
Chronic insomnia disordercommonDifficulty initiating/maintaining sleep or early awakening at least 3 nights/week for at least 3 months with daytime impairmentClinical diagnosis + sleep diary; exclude other primary drivers
Anxiety / panic / PTSDcommonRumination, hyperarousal, nightmares, trauma reminders, nocturnal panic, avoidance of sleep due to fearGAD-7/PTSD screen; trauma-informed history
Restless legs syndromecommonUrge to move legs, worse at rest/evening, relieved by movement; associated with iron deficiency, pregnancy, CKDClinical criteria + ferritin/iron studies
Medication/substance-induced insomniacommonStimulants, antidepressants, steroids, decongestants, beta-agonists, thyroid replacement, caffeine, cannabis rebound, alcohol fragmentationMedication/substance timeline
Circadian rhythm sleep-wake disorderless commonDelayed sleep phase, shift work, jet lag, irregular schedule; sleep normal when allowed preferred scheduleSleep diary/actigraphy and schedule history

Red Flags & Key History

Symptoms
Decreased need for sleep with increased energy or risky behaviour — mania/hypomania
Insomnia with suicidal ideation, psychosis, severe depression, or inability to function
Snoring with witnessed apnoeas, daytime sleepiness, or drowsy driving
Withdrawal symptoms after reducing alcohol, benzodiazepines, opioids, or cannabis
Parasomnia with injury, violent dream enactment, or new onset in older adult
Sleep onset insomnia with rumination and clock-watching
Signs
Elevated BMI, large neck circumference, hypertension, crowded oropharynx (OSA risk)
Pressured speech, psychomotor agitation, disinhibition
Tremor, diaphoresis, tachycardia in withdrawal
Pallor or signs of iron deficiency in restless legs syndrome

Approach to Investigation

First-line
Sleep diaryTrack bedtime, sleep onset latency, awakenings, wake time, naps, caffeine/alcohol/cannabis, exercise, and medications for 1-2 weeks
Mood, anxiety, mania, and substance screenAsk about depression, suicide, GAD, PTSD, mania/hypomania, alcohol/cannabis/stimulants, and sedative use
Medication reviewStimulants, antidepressants, corticosteroids, levothyroxine excess, beta-agonists, decongestants, diuretics, caffeine supplements
OSA screenSTOP-Bang or equivalent; ask bed partner about snoring, witnessed apnoeas, choking/gasping
Second-line
Targeted labsTSH if thyroid symptoms; ferritin/iron studies for restless legs; CBC/B12/renal function if symptoms suggest
Home sleep apnoea test / polysomnographyFor suspected OSA, complex sleep disorders, parasomnia injuries, or diagnostic uncertainty
Specialist
CBT-I referralFirst-line chronic insomnia treatment; may be delivered in person, group, or digital formats
Sleep medicine / psychiatry referralSevere OSA, parasomnia injuries, suspected narcolepsy, bipolar disorder, treatment-resistant insomnia, or complex medication dependence
1
Treat the driver
  • Mania, psychosis, severe depression, suicide risk, withdrawal, OSA, restless legs, pain, nocturia, and medication causes require targeted treatment
  • Reduce caffeine/energy drinks, alcohol-before-bed, cannabis dependence, and late stimulant dosing where relevant
2
CBT-I core components
  • Stimulus control: bed for sleep/sex only, leave bed if unable to sleep, fixed wake time
  • Sleep restriction/compression: match time in bed to actual sleep time, then gradually expand as efficiency improves
  • Cognitive therapy: address catastrophic beliefs about sleep; relaxation techniques; sleep hygiene as supporting measure
3
Medication principles
  • Short-term pharmacotherapy may be considered while CBT-I begins, using lowest effective dose and clear stop plan
  • Avoid chronic benzodiazepines/Z-drugs where possible; avoid in older adults, OSA, falls risk, substance use disorder, pregnancy when possible, and concurrent opioids/alcohol

Complications & Pitfalls

  • Missing mania: A patient who sleeps 2 hours and feels energised is not simply insomniac.
  • Reflex hypnotic prescribing: Chronic benzodiazepines and Z-drugs can worsen falls, cognition, driving risk, and dependence.
  • Overlooking OSA: Sedatives can worsen sleep-disordered breathing.
  • Sleep hygiene alone: Sleep hygiene is not CBT-I and is often insufficient for chronic insomnia.
MCCQE1 Exam Tips
  • 1Best first-line treatment for chronic insomnia is CBT-I, not a benzodiazepine
  • 2Reduced need for sleep + high energy is mania until proven otherwise
  • 3Snoring, witnessed apnoeas, morning headache, hypertension, and daytime sleepiness should trigger OSA assessment
  • 4Restless legs: symptoms worse at rest/evening and relieved by movement; check ferritin
  • 5Avoid benzodiazepines/Z-drugs in older adults and substance use disorder when possible
  • 6A sleep diary is a high-yield, low-cost next step
practicetest your knowledge on insomnia & sleep disturbanceApply what you've learnt with MCCQE1-style questions from the iatroX Q-Bank — psychiatric and beyond.
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Verified Sources & References

Centre for Effective Practice — Management of Chronic Insomnia
Canadian Family Physician — Treatment of Chronic Insomnia in Adults
DSM-5-TR — Sleep-Wake Disorders