Premorbid personality assessments of first onset of major depression.

This is a report on personality traits associated with the first onset of major depression in a sample of high-risk subjects. The subjects are the first-degree relatives, spouses, and their controls of patients with affective disorders. None of these subjects had any history of mental disorder as of their initial evaluation. In the subsequent six years, 29 subjects had a first onset of major depression. These first onset subjects were compared with 370 subjects who continued to be free of illness during the six-year follow-up. Personality traits were assessed at the initial evaluation (ie, before the onset of depression in subjects with first onset) by means of scales from five self-report inventories. Lower emotional strength and resiliency significantly differentiated the first onset from the never ill group; overall differences were not found on measures of interpersonal dependency or extraversion. Age was a significant predictor of first onset, both alone (younger age predicted first onsets) and in interaction with personality measures. Among younger subjects (17 to 30 years of age), personality variables did not significantly discriminate between the two comparison groups. Among older subjects (31 to 41 years of age), however, decreased emotional strength, increased interpersonal dependency, and increased thoughtfulness were associated with first onset of depression.