Neurologic soft signs in schizophrenic patients treated with conventional and atypical antipsychotics.

Neurologic soft signs (NSS) are considered a somatic feature associated with schizophrenia (DSM-IV) that are present in neuroleptic-treated, as well as untreated or first-episode patients. The aim of this study was to determine the incidence and severity of NSS in groups of schizophrenic patients treated with either a conventional neuroleptic medication, haloperidol (n = 37), or atypical antipsychotic medications, risperidone (n = 19), clozapine (n = 34), and olanzapine (n = 18). NSS were assessed with the Neurological Evaluation Scale (NES), whereas extrapyramidal symptoms (EPS), which occur more commonly with conventional neuroleptic treatment, were evaluated using the Simpson-Angus Scale. NES scores were not significantly different between groups. Slight differences were found for 2 items only. The haloperidol group showed higher scores for the "Romberg test," whereas the clozapine group showed higher scores for "short-term memory." There were significant correlations between EPS and NES total score in the haloperidol and risperidone groups. These results demonstrate an overall overlapping of NSS among the groups, confirming their substantial independence from neurologic implications of neuroleptic treatment.