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Effects of haloperidol and risperidone on cerebrohemodynamics in drug-naive schizophrenic patients
Shin-Min Lee1, Yuan-Hwa Chou, Min-Hui Li
1Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan.
Background:
Use of antipsychotics may be associated with cerebrovascular adverse events in psychotic patients. In this study, the effects of haloperidol and risperidone on the cerebral hemodynamics and the possible relationships between antipsychotics and cerebrovascular risks tendency were evaluated by Transcranial Doppler ultrasonography (TCD).
Methods:
Twenty drug-nai ve schizophrenic patients and 20 normal control subjects were included. The patients were divided into haloperidol- and risperidone-treated groups and received treatment for 8 weeks double-blindly. The subjects' cerebral blood flow mean velocities (MV) and pulsatility index (PI) were measured weekly by TCD. The Positive and Negative Syndrome Scale for schizophrenia (PANSS) was used to assess the patients' psychopathological symptoms.
Results:
Increased MV and decreased PI were found significantly in drug-nai ve schizophrenic patients than normal subjects before treatment (p<0.01). The decreased PI could be normalized after 8 weeks of antipsychotic treatment, while the increased MV could not. Treatment with haloperidol could significantly increase the PI than the treatment with risperidone (p<0.01) throughout the treatment course. The PANSS scores of both groups were significantly improved (p<0.05) at the endpoints of treatment.
Conclusions:
Our findings indicate that haloperidol may affect the cerebral hemodynamics in drug-naive schizophrenics more prominently than that of risperidone via TCD monitoring.
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