Analysis of magnetic resonance spectroscopy in patients with obsessive-compulsive disorder comorbid skin-picking disorder.

OBJECTIVES: To investigate the neurobiochemical characteristics of the anterior cingulate cortex (ACC) in patients with obsessive-compulsive disorder (OCD) comorbid skin-picking disorder (SPD), and to provide reference for the pathophysiological basis for OCD. METHODS: We examined the levels of glutamate and other neurochemicals in ACC of 30 adult OCD patients (13 with comorbid SPD, 17 without SPD), using proton magnetic resonance spectroscopy (1H-MRS) at 3T. The clinical evaluation and the quantitative analysis of metabolites were carried out in the two groups. RESULTS: OCD patients with comorbid SPD showed significantly lower ACC glutamate than the patients without SPD (P=0.001). In all OCD patients, glutamate was negatively correlated with scores of Hamilton Anxiety Rating Scale (r=-0.55, P=0.002). Moreover, the ACC glutamate of female patients was correlated with the total score of Yale-Brown Obsessive Compulsive Scale (r=0.69, P=0.041) in the OCD with comorbid SPD patients. CONCLUSIONS: Alterations of the glutamate content in the ACC are involved in the pathophysiological process of OCD with comorbid SPD, which provides evidence for the study on the pathogenesis of OCD and SPD.