Regional homogeneity in patients with obsessive-compulsive disorder and depression: a resting state functional magnetic resonance imaging study

Abstract Objection: To explore the brain functional impairment in patients of obsessive-compulsive disorder (OCD) with and without depressive symptoms, and then analyze the correlation between the degree of impairment and the severity of symptoms. Method: In this study, 14 patients with OCD who met the ICD-10 diagnostic criteria for "obsessive-compulsive disorder" were included; the OCD with depression (OCDd) group consisted of 15 patients; and 17 healthy controls (HC) matched for age and education were included. The Yale-Brown OCD Scale (Y-BOCS) and the 24-item Hamilton Assessment of Depression Scale (HAMD) were administered to the OCD group and the OCDd group. Resting-state functional brain magnetic resonance imaging was performed in three groups of participants. Result: The OCDd group had lower scores on the HAMD, Y-BOCS, and obsessive-compulsive thinking subscales than the OCD group ( P < 0.05). Scores on the OCDd subscale were negatively correlated with HAMD scores ( R = -0.568, P = 0.027). The OCDd group had higher ReHo values in the lingual gyrus than the OCD group. The OCDd group had higher ReHo values in the lingual gyrus than the HC group, while the OCDd group had higher ReHo values than the HC group. These differences were statistically significant ( P <0.05). After correction for multiple comparisons, there was no significant difference between the OCDd and HC groups ( P >0.05). In the OCD group, the ReHo value of the tongue was negatively correlated with the Y-BOCs total score and the compulsive behavior subscale score ( R = -0.609, -0.552, P = 0.016, 0.033). Conclusion: Abnormal ReHo values in the lingual gyrus and right medial superior frontal gyrus were found in patients with OCD. No effect of OCD symptoms on the local coherence of brain function was observed, which may indicate that OCD symptoms are not responsible for the changes in local coherence of the brain, but are caused by depressive symptoms. In the OCD group, ReHo values of the lingual gyrus were negatively correlated with scores on the Y-BOCs total and obsessive-compulsive subscales, suggesting that abnormal local coherence of the lingual gyrus may be related to the severity of OCD.