Depressive personality in the relatives of outpatients with dysthymic disorder and episodic major depressive disorder and normal controls

Background. This study examined whether there is a familial relationship between depressive personality and the mood disorders. Method: Rates of depressive personality were compared in 161 relatives of outpatients with dysthymic disorder (DD), 75 relatives of outpatients with non-chronic major depressive disorder (MDD), and 90 relatives of normal controls. All probands and relatives were evaluated using structured diagnostic interviews for Axis I disorders and depressive personality traits. Results: The relatives of patients with DD exhibited a significantly higher rate of depressive personality than the relatives of normal controls, while the relatives of patients with MDD fell in between, and did not differ from, the other two groups. These results held after controlling for a lifetime history of mood disorder in the relatives, and could not be explained by an increased rate of depressive personality in the DD probands. Limitations: The sample size was modest, comorbid non-mood Axis I and II disorders in the relatives were not controlled, and DSM-IV criteria for depressive personality disorder were not yet available at the time the study was undertaken. Conclusion: These findings are consistent with the view that depressive personality is part of a spectrum of mood disorders with a shared familial liability, but suggest that this link is strongest with chronic forms of depression such as DD and double depression. (C) 1999 Elsevier Science B.V. All rights reserved.