DSM-III-R axis II comorbidity in dysthymia and major depression.

Objective: Dysthymia is generally believed to be associated with a high rate of DSM-III-R axis II comorbidity. However, it is unclear whether this rate is higher than that for other axis I disorders, how many dysthymic patients have personality disorders, and what the most common co-occurring axis II conditions are.

Methods: Ninety-seven outpatients with early-on-set dysthymia and 45 with episodic major depression were administered structured diagnostic interviews for axis I and II disorders. In addition, knowledgeable informants were independently interviewed about axis II conditions in the patients.

Results: A significantly greater proportion of dysthymic patients (60%) than patients with episodic major depression (18%) met criteria for a personality disorder. The most common axis II conditions among dysthymic patients were borderline, histrionic, and avoidant personality disorder. Informants' reports yielded similar results.

Conclusions: These data indicate that early-onset dysthymia is associated with significantly greater axis II comorbidity than episodic major depression. Further work is necessary to elucidate the processes underlying this association.