Effects of haloperidol and risperidone on psychomotor performance relevant to driving ability in schizophrenic patients compared to healthy controls

The effects of antipsychotic treatment on the psychomotor performance and driving ability of schizophrenic patients is subject of investigation. The present study was designed to evaluate the effects of an atypical neuroleptic (risperidone) in comparison to a conventional dopamine antagonist neuroleptic (haloperidol) on several dimensions of psychomotor performance (visual perception, attention, reaction time, and sensorimotor performance) considered to be of relevance in evaluating driving fitness. Psychomotor performance was assessed by means of the ART 90 (act-and-react test), a computerized test battery which is frequently used in diagnosis of psychomotor performance. The 40 participating patients were examined at discharge following psychopathological stabilisation; 20 received haloperidol medication, 20 received the atypical neuroleptic risperidone. Nineteen healthy individuals were studied as a control group. Our findings indicate a remarkably reduced psychomotor performance in both groups of schizophrenic patients compared to healthy controls. We did find a significant but low correlation between age and some items of the RST3 and between age and the tracking performance on the PVT. The younger patients showed a better test performance than older patients. The BPRS-score was significantly correlated with only two items of the RST3. However, patients under treatment with risperidone showed significantly better results compared to patients treated with haloperidol. Only one (5%) subject passed all subtests without major failures and could be regarded as competent to drive. Among patients with risperidone, seven patients (35%) passed all test parameters without major failures. Clinical implications of these findings are discussed.