Sex differences in inpatients with obsessive–compulsive disorder

Background: Sex differences in obsessive–compulsive disorder (OCD) have been observed across several domains, including epidemiology and clinical presentation (e.g., age of disorder onset, comorbid mental disorders, OCD symptom dimensions). However, findings have been mixed, particularly with regard to possible sex differences in treatment outcome.Method: Data of 2540 adolescents (16%, n = 417) and adults (84%, n = 2123) with OCD (59% female, n = 1508) who received inpatient treatment at the Schoen Clinic Roseneck (Prien am Chiemsee, Germany) between January 2015 and April 2024 were analyzed.Results: Female patients were younger, had a longer length of stay, were more likely to have OCD subtype with predominantly compulsive acts and comorbid anxiety-related and eating disorders and were less likely to have behavioral and emotional disorders with onset usually occurring in childhood and adolescence than male patients. When examining self-report questionnaires, female patients had higher scores for compulsions in general and compulsive washing in particular, and for depressive, somatic, and anxiety symptoms. There were no sex differences in changes in OCD-specific and other symptoms from admission to discharge based on both self-reports and therapist ratings.Conclusion: Despite sex differences in OCD symptom dimensions and comorbid symptoms, treatment response was comparable for female and male patients. These findings suggest that while sex may shape how OCD manifests, it does not appear to influence the degree of symptom improvement achieved during inpatient treatment.