Previous studies suggest that many untreated schizophrenia patients
exhibit motor disturbances. On the basis of these findings, the authors
hypothesized that preexisting extrapyramidal movement disorders may
increase the risk of developing neuroleptic-induced parkinsonism (NIP).
Thirty-five newly medicated psychotic patients underwent pretreatment
clinical and instrumental motor and psychiatric assessments. Posttreatment
ratings of parkinsonism were conducted at monthly intervals for the first 3
months and every 3 months thereafter. Thirteen patients (37%) developed
NIP. Advanced age and pretreatment extrapyramidal disturbances predicted
NIP. Life-table survival curves indicated that patients with pretreatment
instrumental rigidity developed clinically significant NIP earlier than
those without rigidity. These findings suggest that pretreatment motor
dysfunction may be a risk factor for drug-induced parkinsonism, especially
among older patients.