Familiality of major depressive disorder and gender differences in comorbidity

Objective: Gender differences exist in the prevalence and psychiatric comorbidity of major depressive disorder (MDD). This study investigates whether familiality of MDD contributes to observed gender differences in comorbidity. Method: Familial (f‐MDD) and non‐familial (nf‐MDD) MDD cases from a population sample were assessed for comorbid dysthymia, anxiety disorders and alcohol‐related disorders using the Composite International Diagnostic Interview (CIDI). Logistic regression analyses were performed to examine the effect of f‐MDD on gender differences in comorbidity, adjusted for confounders. Results: Women with f‐MDD reported significantly more comorbid dysthymia and generalized anxiety disorder (GAD) than their male counterparts; women with nf‐MDD reported significantly more comorbid simple phobias and agoraphobia than their male counterparts. Gender differences in comorbid panic disorder and alcohol‐related disorders occurred independently of the familial load. Adjustment for age of onset, severity and recurrence of MDD did not change these results. Conclusion: Models to explain comorbidity patterns of MDD differ by gender. Familiality of MDD should be taken into account.