Major depression, double depression and personality disorders.

Personality disorders are much more common among depressive patients than among normal people. Until now, little research has been conducted into the prevalence of personality disorders among patients with both major depression and dysthymia (double depression). The subject of this study is whether depressive patients with dysthymia have more personality disorders than those with no dysthymia. The Vragenlijst voor Kenmerken van de Persoonlijkheid (a Dutch self-report based on the International Personality Disorder Examination) was completed for 211 outpatients with major depression. Approximately 60% of the patients suffer from one or more personality disorders. Depressive patients with dysthymia differ little from the patients without dysthymia, but patients with dysthymia have more cluster A disorders and are more avoidant. Depressive patients without dysthymia do not differ from the patients with dysthymia in terms of symptoms. Depressive patients with personality disorders have significantly more symptoms than the patients without these disorders. There is no interaction between dysthymia and personality disorder.