Decreased cortical thickness in obsessive compulsive disorder: a meta-analysis of brain structural magnetic resonance imaging studies.

Motivation: Although studies indicate abnormalities in cingulo-opercular and default mode networks in obsessive-compulsive disorder (OCD), neuroimaging evidence of brain structural alterations is still limited and contradictory. Goal(s): To compare cortical thickness (CTh) between patients with OCD and healthy controls. Approach: We performed a meta-analysis on CTh and conducted subgroup analyses and meta-regression analyses to explore the effects of confounding factors on CTh. Results: Our study found decreased CTh in the left posterior cingulate cortex (PCC), left dorsal anterior cingulate cortex (dACC), and right pars opercularis in OCD. Medicated-subgroup analysis showed no between-group differences in dACC, though reduced CTh of PCC and pars opercularis remained. Impact: Our study found decreased CTh in cingulo-opercular and default mode networks in patients with OCD, which helped explore the neural mechanism of OCD, and also suggested that medication might have an impact on CTh alterations in OCD.