Personality disorders in dysthymia and major depression

The purpose of the present study was to investigate the comorbidity of personality disorders in patients with primary dysthymia compared to those with episodic major depression.

A total of 177 out-patients with primary dysthymia and 187 outpatients with episodic major depression were administered a structured diagnostic interview for DSM-III-R Axis II disorders. In addition, all of these patients completed the BDI, and those with the appropriate level of education also completed the Minnesota Multiphasic Personality Inventory (MMPI).

A significantly higher proportion of dysthymic patients than patients with major depression met the criteria for a personality disorder, for borderline, histrionic, avoidant, dependent, self-defeating types and for personality disorders of clusters B and C. Further analysis revealed that the above differences were mainly due to the subgroup of patients with 'early-onset dysthymia'. Finally, patients with a personality disorder, both dysthymics and those with major depression, had significantly higher scores on the BDI and on the majority of the MMPI scales compared to those without a personality disorder.

The data indicated that (i) dysthymia--mainly that of early onset--is associated with significantly higher personality disorder comorbidity than episodic major depression, and (ii) the presence of a personality disorder is related to more severe overall psychopathology.