The impact of antipsychotics on psychomotor performance with regards to car driving skills

Cognitive and psychomotor impairments are a core feature of most patients with schizophrenia and may have an important influence on driving ability. The present study investigated the effects of neuroleptic monotherapy on psychomotor functions related to car driving skills in schizophrenic patients. Consecutively admitted schizophrenic inpatients (n = 120) were tested under steady state plasma level conditions before discharge to outpatient treatment. Patients met the International Classification of Diseases, Tenth Revision criteria for schizophrenia. The study followed a naturalistic nonrandomized design. Data were collected with the computerized Act & React Testsystem and were analyzed according to medication, severity of illness, and age. Only 32.5% of the schizophrenic inpatients passed the tests without major impairments. Patients treated with atypical neuroleptics or clozapine showed a better test performance on skills related to driving ability when compared with patients on typical neuroleptics. Differences were most pronounced in measures of divided attention, stress tolerance, and attention. Data also suggest that treatment with clozapine had an overall positive impact on measures of reactivity and stress tolerance. These results show that even under steady state pharmacologic conditions psychomotor functions of most schizophrenic patients partly remitted must be considered as impaired. To evaluate these effects, a systematic neuropsychologic examination is recommended.