Sleep Measures of Patients with Schizophrenia Treated with Risperidone, Clozapine, or Haloperidol

Objective: In this cross-sectional observational study, we intended to compare objective and subjective sleep measures in schizophrenic patients treated with clozapine, risperidone or haloperidol. Methods: We used polysomnography and the Chinese version of Pittsburgh Sleep Quality Index (CPSQI) scores, to compare schizophrenic patients receiving risperidone (n=15), haloperidol (n=13) and clozapine (n=12). All patients were diagnosed according to the DSM-IV criteria, and clinical symptoms were evaluated by Brief Psychiatric Rating Scale (BPRS). Results: No signifi cant differences were found in the comparison of three treatment groups in demographic characteristics, antipsychotic potency, the BPRS scores and CPSQI and its sub-factors. Compared to the clozapine treated group, both haloperidol-and risperidone-treated group had a significantly less stage 2 sleep and less stable non-REM sleep (stage 2, 3 and 4). Only patients treated with haloperidol showed significantly more stage 1 sleep than the clozapine-treated group. Conclusions: Signifi cant differences were not found in subjective perceptions of sleep quality among schizophrenic patients treated with clozapine, risperi-done or haloperidol. Clozapine was found to induce enhancement of non-REM sleep, especially an increase of stage 2 sleep. The D4 and the 5-HT receptor antagonist affinities of clozapine contribute to most of its clinical properties on sleep. Larger patient samples, longitudinal design, and baseline recordings are needed in future studies to confirm of this cross-sectional observational study.