Treated versus untreated major depressive episodes.

It is a plausible hypothesis that among treated cases of major depressive episodes (MDE) in the community, females will be overrepresented, episodes will be more severe, the course of the disorder will be more frequently chronic and the consequences in the depression more serious. This hypothesis was tested on the subjects of the Zürich cohort study, an enriched population sample (n = 591), which was examined 5 times between the ages of 20 and 35. We found a longitudinal prevalence rate for MDE of 20.2% (13.5% for males and 26.7% for females). 173 subjects met DSM-IV criteria for MDE and of those 66 (38%) had been treated for depression in the preceding 12-month period. 82% of the treated cases were females; in untreated subjects the sex ratio F/M was 1.2:1. Treated cases were found to be more severely depressed, they spent more days in depression over 1 year, experienced greater suffering and suffered more work and social impairment. However, in terms of family history of depression and age of onset, treated and untreated cases did not differ. Surprisingly, there was a trend to a more favorable course among treated subjects than in the untreated group. Compared with controls, untreated subjects demonstrated normal coping skills. The treated cases differed from both untreated subjects and controls in their aggression and neuroticism scores.