Obsessive-compulsive spectrum disorders: cross-national and ethnic issues.

Epidemiological and clinical data from a variety of cultural and geographic settings on obsessive-compulsive disorder (OCD), and many of the obsessive-compulsive spectrum disorders, suggest that this is a group of disorders with a good degree of transcultural homogeneity. However, the content and themes that predominate in patients with these disorders, and the course of illness, can be shaped by cultural, ethnic, and religious experiences. Across cultures, OCD is commonly comorbid with mood, anxiety, and impulse-control disorders. However, little is known about the mechanisms by which culture and ethnicity may affect the expression of OCD and related disorders. Cross-national comparative studies exploring culturally influenced differences in clinical course, treatment outcome, including ethnogenetic differences in drug response, and prognosis are needed.