Neurological soft signs in OCD patients with early age at onset, versus patients with schizophrenia and healthy subjects.

Compelling evidence suggests that both schizophrenia and obsessive compulsive disorder (OCD) are related to deviant neurodevelopment. Neurological soft signs (NSS) have been proposed to be a marker of abnormal brain development in schizophrenia. The purpose of this study is to examine whether NSS are also a marker in patients with OCD, in particular, in early-onset OCD. The authors included 162 subjects and compared patients with OCD, patients with schizophrenia (SCZ), and healthy control subjects. They were all examined for NSS (Krebs' Scale), extrapyramidal symptoms (Simpson-Angus Scale), and were rated on the Abnormal Involuntary Movements Scale (AIMS). The authors found no differences between NSS total scores and subscores in OCD versus controls, whereas total NSS, motor coordination, and motor integration were significantly lower in OCD than in SCZ. OCD patients with early-onset (before age 13) did not differ from those with later-onset OCD. These results support the idea that NSS, as determined by current scales, is relatively specific to schizophrenia, although they do not preclude the existence of a neurological dysfunction in OCD. Further studies are required to determine the type of neurological signs that could be useful trait-markers in the phenotypic characterization of subtype OCD.