The Depressed Client Who Has "Good Stretches"
Marcus, 34, has been in treatment for 9 weeks for a third major depressive episode in five years. Sertraline was raised to 100 mg six weeks ago; his PHQ-9 fell from 19 to 11. In passing he mentions "good stretches" - every month or so he goes two or three days sleeping four hours, talking fast, starting several projects at once, and feeling "wired but great." He has never been hospitalized or psychotic, and his worst overspending was about $400 on a credit card. His mother has bipolar I disorder. He drinks two or three beers on weekends. He asks whether he is "just depressed" and wants the dose raised again.
1. What belongs on your differential, and what specific information would separate the possibilities?
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Do not anchor on recurrent MDD just because the depression is obvious.
Candidate explanations:
- Bipolar II - requires a hypomanic episode of at least 4 consecutive days (3+ symptoms if mood is only elevated; 4+ if irritable). Two-to-three-day episodes do not meet the duration threshold.
- Other specified bipolar and related disorder (short-duration hypomanic episodes) - fits if episodes are 2–3 days with clear change in functioning and are not better explained otherwise. This is a clinically meaningful label, not a throwaway.
- Substance/medication-induced bipolar - establish the timeline: did the first "wired" stretch predate sertraline? Ask specifically about activation after each dose increase.
- Medical contributors - thyroid, anemia, stimulant or caffeine use.
Information to gather: prospective daily mood charting, collateral from a partner or sibling, a detailed family history (which relative, which illness, any lithium or hospitalization), and substance pattern. Cyclothymia is unlikely given episodic major depression and a 5-year history.
2. Given your leading hypothesis, what are the treatment implications, and how do you answer his request for another dose increase?
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The diagnosis matters less than the prescriber conversation it triggers.
- Antidepressant monotherapy in someone with probable bipolar-spectrum illness risks activation, mixed features, and cycle acceleration - so "raise it again" is not a neutral request.
- Do not stop or change his medication yourself. Contact the prescriber the same week with a structured summary: episode dates, symptoms, duration, relation to dose changes, family history.
- Raise mood stabilizer or atypical antipsychotic augmentation as a question for the prescriber, not a recommendation.
- Tell Marcus what you observed and why it changes the plan: "You've described two-to-three-day stretches that look like a mild high. That's why the plan usually changes - it isn't because you're not trying."
- Enroll him and a collateral informant in mood charting so any decision rests on prospective data, not recollection.
- Screen for risk: mixed features and impulsivity raise suicide risk even when the PHQ-9 improves.
3. Which instruments would you use, and what are their limits here?
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Screening is not diagnosing.
- MDQ - reasonable sensitivity but low specificity, especially in general outpatient settings; it produces many false positives. A positive screen only tells you to interview further.
- Structured interview (SCID-5 or MINI module) - needed to establish duration, symptom count, and impairment for each episode.
- Prospective mood diary or life chart - the strongest evidence here, since retrospective recall of 2–3 day episodes is unreliable.
- PHQ-9 - track depression severity but is blind to hypomania; pairing it with a bipolar screen is the point.
- AUDIT-C - brief, adequate for his weekend drinking.
Limits to state plainly: no self-report scale establishes episode duration; a normal screen does not rule out bipolarity when collateral history is positive. Document the discrepancy between his PHQ-9 improvement and the untreated hypomanic symptoms - that gap is the clinical finding.