Personality disorders in dysthymia and major depression

Objective: 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. Method: 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). Results: 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. Conclusion: 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.