Obsessive–compulsive symptoms are induced or aggravated by stress, and the pituitary is a key component of the hypothalamic-pituitary-adrenal axis. We examined pituitary volume in drug-naïve and medicated male patients with obsessive–compulsive disorder (OCD).Methods
Volumetric magnetic resonance imaging studies were conducted on 62 male control subjects, medicated male patients (N = 50) and drug-naïve male patients (N = 12) with OCD.Results
Pituitary volume was significantly smaller in drug-naïve patients with OCD (464.97 ± 55.82 mm3) compared to medicated patients (577.84 ± 129.11 mm3, P = 0.004) and control subjects (543.04 ±113.70 mm3, P = 0.027), and no difference between control subjects and medicated patients (P = 0.174).Conclusion
The results indicate that drug-naïve male patients with OCD exhibit decreased pituitary volume. This finding suggests that dysregulation of the HPA axis in OCD may influence pituitary volume. In addition, the increased pituitary volume in medicated patients may reflect the effect of drugs on the pituitary.