Adult depression — KFP-style written assessment

KFP 1 (10 marks)

A 46-year-old accountant presents with six weeks of low mood, morning fatigue and reduced enjoyment of her usual activities. She wakes at 4 am but denies any thoughts of self-harm. PHQ-9 is 11 (moderate). She has no history of elevated mood. TSH and FBC are normal; she drinks two glasses of wine a night. ^{[1] [2]}

1. State the DSM-5 criteria she must meet for a major depressive episode and how her PHQ-9 score should be used. (4) ^[1]
2. Outline your first-line management options with their comparative evidence base. (4) ^{[13] [11]}
3. What will you tell her about expected onset and review timing? (2) ^[18]

Model answers

1. DSM-5 requires five or more symptoms in the same two-week period representing a change from prior functioning, including depressed mood or anhedonia, causing clinically significant distress or functional impairment, not attributable to substances or another medical condition and not better explained by mania/hypomania. Her PHQ-9 of 11 sits in the moderate band (10–14); the instrument detects major depression at a cut-off of 10 with ~88% sensitivity and 0.85–0.88 specificity, so it structures severity and monitoring while the diagnosis remains clinical. ^{[1] [2]}
2. Most guidelines recommend initial treatment with either CBT or a second-generation antidepressant for moderate depression; neither provides consistently superior cost-effectiveness, and patient preference should steer the choice. If pharmacotherapy, sertraline or escitalopram are preferred — all 21 antidepressants beat placebo for efficacy, but these top acceptability profiles. Address alcohol as a perpetuating factor. ^{[13] [11]}
3. Meaningful benefit typically begins within 1–2 weeks, full response by 4–6 weeks. Book review at 2 weeks to check adherence, side effects, activation and risk — but do not reflexively switch early non-improvers: paroxetine non-improvers at 2 weeks did equally well on paroxetine, mirtazapine or combination by week 8. A documented plan replaces silent continuation. ^[18]