Suicide in subtypes of major affective disorder. A comparison with general population suicide mortality.

We investigated the risk of suicide among 705 patients with primary unipolar depression, 302 patients with secondary unipolar depression, and 586 patients with bipolar affective disorder (BAD). The suicide rates among the study subjects were compared with that of the general population of Iowa, the area from which the subjects were selected. An increased risk of suicide was found in all psychiatric groups, except the group of female patients with BAD, which was associated with a lower risk of suicide than unipolar disorders. Thirty suicides (73.2%) occurred during the first two years of follow-up; this trend was particularly pronounced in female patients with primary unipolar depression and male patients with BAD.