Axis I and II comorbidity in a large sample of patients with obsessive-compulsive disorder

No study has reported yet on the prevalence of both comorbid DSM-IV axis I and personality disorders in a large cohort of OCD patients, and little is known about differences in clinical characteristics between OCD patients with and without comorbid symptoms.

To examine the cross-sectional prevalence of comorbid DSM-IV axis I, and personality disorders in a population of patients with primary obsessive-compulsive disorder (OCD).

420 outpatients with OCD were evaluated for comorbid pathology, demographic, and clinical characteristics.

Forty-six percent of the patients were diagnosed with a comorbid disorder. Twenty-seven percent met the criteria for at least one comorbid axis I disorder, 15.6 percent for a comorbid personality disorder, and 20.4 percent for both a comorbid axis I disorder and a personality disorder.

A limitation of the current study is that the sample was drawn from a psychiatric department specialised in anxiety disorders, which might have underestimated the rate of comorbid diagnoses.

Comorbid diagnoses occur less frequently than would be expected on the basis of comparable comorbidity studies in OCD. Associated axis I comorbidity did not affect clinical severity of OCD, but was related to higher levels of depression and anxiety, whereas axis II comorbidity impaired to a higher extent the overall functioning.