Psychiatric disorders in relatives of probands with obsessive-compulsive disorder and co-morbid major depression or generalized anxiety.

The authors report findings from a blind, controlled study of obsessive-compulsive disorder (OCD). Prevalence rates of generalized anxiety disorder (GAD) and major depressive disorder (MDD) were compared among first-degree relatives of probands with OCD and co-morbid GAD or MDD, respectively. Rates of MDD were not increased in relatives of probands with OCD and MDD; neither were rates of GAD increased in relatives of probands with OCD and GAD, although rates of GAD were increased among relatives of probands with OCD compared to relatives of healthy controls. The authors explore the implications of the findings.