FAMILIAL TRANSMISSION OF PANIC DISORDER - EFFECT OF MAJOR DEPRESSION COMORBIDITY

This study assesses the effect of major depressive disorder (MDD) como rbidity on familial transmission of panic disorder (PD). The following questions are addressed: (1) is PD familial, i.e., do relatives ofpat ients with PD show an increased risk for PD? (2) do PD and MDD share a common diathesis, i.e., do relatives of patients with PD without MDD show an increased risk for MDD? (3) is lifetime comorbid PD with MDD c onjointly familial, i.e., do relatives of patients with PD and MDD sho w an increased risk for the combined syndrome? Subjects were: (1) 152 relatives of 54 anxiety clinic patients with PD and MDD; (2) 193 relat ives of 72 patients with PD without MDD; (3) 231 relatives of 77 not i ll controls. Relatives were interviewed by clinicians, and best estima te DSM-III-R diagnoses were formulated by senior staff. Relatives of P D with MDD (13%) and PD without MDD probands (9%) showed significantly higher rates of PD than relatives of controls (3%). Relatives of PD w ith MDD probands (37%) showed significantly higher rates of MDD than r elatives of PD without MDD (24%) and controls (21%), with no differenc e between the latter two groups. Relatives of PD with MDD probands (9% ) showed significantly higher rates of PD with MDD than relatives of P D without MDD (3%) and controls (1%). We conclude that: (L) PD is fami lial; (2) PD in the absence of MDD does not incur increased risk of MD D to relatives; and (3) PD with MDD may represent a distinct, complex syndrome. (C) 1995 Wiley-Liss, Inc.