BRADYKINESIA AND MENTAL SLOWNESS IN PATIENTS WITH OBSESSIVE-COMPULSIVE DISORDER

Background: Clinical and experimental findings suggest that Obsessive-Compulsive Disorder (OCD) is due to an abnormality of the cortico-striato-thalamo-cortical circuit. Bradykinesia and mental slowness can be present in patients with basal ganglia disorders affecting the cortico-striato-thalamo-cortical circuit. Aim of this study is to investigate whether bradykinesia and mental slowness are present in patients with OCD. Methods: Participants comprised 19 non-depressed anti-psychotic free patients with OCD. Bradykinesia was assessed with the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS). Mental slowness was investigated with the WAIS-R and the Y-BOCS. Psychiatric evaluation was performed with: SCID-I, Y-BOCS, HAMD, HAM-A, and MMPI. Cognitive functions were assessed with the WAIS-R. Results: Bradykinesia and mental slowness were present respectively in the 39% and 89% of the patients. Bradykinesia was positively correlated to Y-BOCS mental slowness score (rho=0.48, p< 0.05), and inversely related to the WAIS-R Performance IQ score (rho=-0.65, p< 0.01). Patients with bradykinesia scored significantly lower in the Similarities and Digit symbol coding WAIS-R subscales as compared to non-bradykinetic patients. in our sample pathological doubt was not associated with IQ measures nor with bradykinesia. Twelve out of 19 patients (63%) showed impairments in the nonverbal function scores. Conclusions: The novel findings of this study is that bradykinesia can be present in patients with OCD, and it is correlated with mental slowness and nonverbal performance impairment. These preliminary data support the notion that dysfunction of basal ganglia is possibly present in OCD patients