Background. Demographic data, family history, psychopathological features, comorbidity and course of obsessive-compulsive disorder (OCD) are investigated and data generated to support the possible existence of two subgroups with gender-related differences of a broader nature. Method. Two hundred and sixty-three OCD patients. consecutive admissions to the Institute of Psychiatry, University of Pisa over a period of 5 years, not excluding those with comorbid Axis I and Axis II conditions, were studied. Patients were evaluated with a specifically designed semistructured OCD interview. Results. We found a significantly greater history of perinatal trauma in men who also had an earlier onset. greater likelihood of never having been married and a higher frequency of such symptoms as sexual, exactness and symmetry obsessions and odd rituals; by contrast, women suffered a later onset of the disorder. were more likely to be married, had higher rates of associated panic attacks after the onset of OCD and a higher frequency of aggressive obsessions at the onset of their illness, and were less frequently associated with bipolar disorders. Conclusions. Pathophysiological mechanisms in OCD seem to differ by gender. Perinatal trauma might predispose to earlier onset in men, whereas in women there is a close association between OCD and panic disorder.
