MBBS SAQ · Psychiatry
Major depressive disorder — diagnosis, suicide risk and first-line management
NEET-PG / INICET SAQ on MDD: SIGECAPS threshold, severity grading, suicide risk, SSRI initiation and review, CBT, ECT indications, and bipolar exclusion.
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A 34-year-old primary-school teacher is brought by her sister after 6 weeks of pervasive low mood, loss of interest in teaching and hobbies, early-morning wakening (3 a.m.), reduced appetite with 4 kg weight loss, impaired concentration, fatigue, and excessive guilt that she is a "failure as a mother." She has had passive thoughts that "life is not worth living" but denies a plan, intent, or means. She drinks 2 units of wine on weekends, takes no regular medication, and has no history of elevated mood, psychosis, or previous psychiatric admission. Examination: BP 118/74, HR 78, afebrile, thyroid exam normal, no focal neurology. Thyroid function, glucose, FBC, and B12 are normal. Outline diagnosis, severity, risk assessment, and management. [1]
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Diagnosis: major depressive disorder (MDD), single episode, moderate-to-severe, without psychotic features. She meets the threshold of ≥5 SIGECAPS symptoms for ≥2 weeks, including both depressed mood and anhedonia, with functional impairment. There is no prior manic/hypomanic episode, so this is unipolar (not bipolar). Organic mimics (hypothyroidism, anaemia, B12 deficiency) have been excluded.[1]
SIGECAPS present: Sleep (early waking), Interest (anhedonia), Guilt, Energy (fatigue), Concentration, Appetite/weight, Psychomotor not stated, Suicidal ideation (passive). Depressed mood is additional. [1]
Severity: Moderate-to-severe — marked functional impairment at work/parenting, vegetative features (early waking, weight loss), and suicidal ideation. Not mild (no pure watch-and-wait). Not psychotic (no delusions/hallucinations). Not catatonic. [1]
Suicide risk assessment (mandatory at every contact):
- Ideation: present, passive ("life not worth living")
- Plan / intent / means: denied — currently lower acute intent, but risk is dynamic
- Protective factors: sister support, employment, children, help-seeking
- Risk factors: guilt, hopelessness themes, female sex with perinatal-age stress, recent functional decline
- Document capacity, safety plan, means restriction (medications/alcohol), and next review timing
- Red flags for urgent escalation: active plan, psychosis, severe self-neglect, postpartum harm thoughts, access to lethal means [1]
Immediate management — stepped care:
- Psychoeducation — illness model, delayed antidepressant effect (4–6 weeks), early side effects, when to seek help.
- Psychological therapy — offer CBT (or IPT); first-line for moderate depression alone or combined with medication.
- Pharmacological first-line — start an SSRI, e.g. sertraline 50 mg once daily (or escitalopram 10 mg OD; fluoxetine 20 mg OD). Prefer sertraline for relative safety in overdose and broad evidence base.[2]
- Review at 1–2 weeks for suicidality, adherence, and early adverse effects (GI upset, activation, sexual dysfunction, hyponatraemia risk later). Full efficacy assessed at 4–6 weeks; if partial response, optimise dose before switching.
- Continue effective antidepressant for at least 6–9 months after remission for a first episode; longer if recurrent.
- Lifestyle — sleep hygiene, activity scheduling, alcohol reduction, social support.
- When to escalate — no response after adequate trial → switch SSRI/SNRI or augment; ECT if severe, psychotic, catatonic, life-threatening refusal of food/fluid, or high suicide risk not controllable as an outpatient.[3]
Disposition: Can usually manage as outpatient with close review if risk remains passive, sister can support, and safety plan is agreed. Admit if risk escalates, support collapses, or severe self-neglect develops. [1]
Common errors
- Missing the 2-week / 5-symptom threshold, or diagnosing dysthymia (needs ≥2 years).
- Not excluding bipolar before starting an antidepressant (can switch into mania).
- Starting an antidepressant without a suicide risk assessment and early review plan.
- Expecting full response in days; not warning about the 4–6 week lag.
- Using a TCA first-line in a patient with suicidal ideation (higher overdose lethality).
- Forgetting CBT as a co-equal first-line option with medication.
- Not planning continuation therapy after remission (high early relapse risk). [1]
Examiner notes
- Reproduce SIGECAPS and the diagnostic threshold cleanly.
- State a concrete drug + dose + route + review interval.
- Name ECT indications even if not indicated in this case.
- Link risk assessment language to plan / intent / means / protective factors.
- Mention postpartum and elderly modifiers if asked as variants (irritability in adolescents; somatic presentation in elderly; screen bipolar history carefully postpartum). [1]
References
- [1]McCarron RM, Shapiro B, Rawles J, Luo J. Depression. Ann Intern Med, 2021.PMID 33971098
- [2]Mutz J, Vipulananthan V, Carter B, Hurlemann R, Fu CHY, Young AH. Comparative efficacy and acceptability of non-surgical brain stimulation for the acute treatment of major depressive episodes in adults: systematic review and network meta-analysis. BMJ, 2019.PMID 30917990
- [3]Cipriani A, Furukawa TA, Salanti G, et al. Comparative efficacy and acceptability of 21 antidepressant drugs for the acute treatment of adults with major depressive disorder: a systematic review and network meta-analysis. Lancet, 2018.PMID 29477251