The present study was performed in a group of bulimic (BN) females (1) to assess prevalence rates of comorbid obsessive-compulsive phenomena; (2) to investigate whether BN patients display a characteristic cluster of obsessive-compulsive symptoms; and (3) to determine whether obsessive-compulsive symptoms influence the clinical picture of BN. Thirty-eight DSM-IV BN females were interviewed by means of the Structured Clinical Interview for DSM-III-R (SCID) to assess the prevalence rate of obsessive compulsive disorder (OCD); the Yale-Brown Obsessive-Compulsive Symptom Scale (Y-BOCS) Symptom Check-List was also used to evaluate the presence of obsessive-compulsive symptoms. The phenomenology of BN females with obsessive-compulsive syndromes (OCS) as detected by the Y-BOCS was compared to that shown by a 'control' group of nonbulimic OCD females. Finally, the eating-related psychopathology of BN women with and without OCS was compared. The current prevalence rates of OCD and of subthreshold obsessive-compulsive syndrome (sOCS) in our sample were 10.5% and 15.8%, respectively. Thus, a total of 26.3% of BN females had a current OCS that comprised both clinical disorders and subthreshold syndromes. No differences were detected between obsessive-compulsive symptoms of these females and those of the control group of nonbulimic OCD females. BN females with OCS had higher ratings on the Eating Disorder Inventory (EDI) total score and on the 'drive for thinness' and the 'bulimia' items of the scale, as compared to BN females without OCS. In conclusion, it appears that a considerable proportion of BN females display OCS, which sometimes are not severe enough to fulfill diagnostic criteria for OCD. Moreover, in these patients, obsessive-compulsive symptoms are undistinguishable from those of OCD females, and exert a negative influence on the clinical picture of the bulimic disorder.
