The clinical utility of symptom dimensions in obsessive-compulsive disorder.

Factor analyses in obsessive-compulsive disorder (OCD) have consistently identified several different symptom dimensions. Nevertheless the clinical utility of identifying such symptom dimensions remains somewhat unclear. On the basis of their principal symptoms, 343 OCD patients were divided into four symptom dimension subgroups; 1) contamination/washing, 2) hoarding, 3) symmetry/repeating and ordering, and 4) forbidden thoughts/checking. Clinical variables including 1-year treatment outcome were compared across these patient subgroups. Most patients (74%) could distinctively be categorized as falling into a particular symptom subgroup. The groups were differentially characterized by some demographic and clinical features. For instance, both the symmetry and hoarding groups were significantly associated with decreased global functioning and greater OCD severity. Moreover the hoarding group was significantly more likely than the others to show longer duration of illness, lower rate of marriage, poor insight, and poorer outcome. However, about a quarter of the participants could not be classified definitively into a particular group. Our findings provide partial support for the clinical utility of a simple measure of symptom dimensions in OCD. In clinical settings, however, the limitations of such a simple measure of predominant symptom dimensions should be borne in mind and further work on their validity and utility is needed.