Short-term prognosis in primary and secondary major depression.

Among inpatients treated without ECT, those with primary unipolar depression had significantly better outcomes at discharge than did those with secondary depression. This difference grew more striking during a 6-month follow-up; patients with secondary depression were clearly less likely to recover from the index depressive episode and had substantially higher symptom levels at the time of follow-up. In contrast, patients with DSM-III melancholia resembled depressed patients without melancholia on all outcome measures.