Family history in recurrent depression.

The authors report morbid risks found for depression, alcoholism, and bipolar disorder in first-degree relatives of 179 probands with recurrent depression. Comparisons were made for relatives' gender, probands' gender, and probands' age at onset. Results showed overall morbid risks of 20.7% for non-bipolar depression, 15.4% for alcoholism, and 1.1% for bipolar disorder. Female relatives were found to be at greater risk for depression than males, while the reverse was true for alcoholism. Sex of proband had no effect. Risk to relatives of early-onset probands was significantly elevated compared to late-onset probands. Various cutoffs for ages at onset were examined, and the effect became more marked as the cutoff age was decreased to 20.