Influence of aging on the improvement of subjective sleep quality by atypical antipsychotic drugs in patients with schizophrenia - Comparison of middle-aged and older adults

Objective: The authors investigated the influence of aging on the improvement of subjective sleep quality by atypical antipsychotic drugs in patients with schizophrenia. Methods: Subjects were 86 inpatients ( mean age: 61.4 years) who had been receiving treatment with conventional antipsychotic drugs and who met DSM-IV criteria for schizophrenia. Their antipsychotic medication was changed from conventional antipsychotics to one of four atypical antipsychotic drugs ( olanzapine, perospirone, quetiapine, or risperidone). Patients were grouped by age ( older or younger than 65 years). Subjective sleep quality and psychopathology were assessed twice: 1) at baseline, and 2) 8 weeks after switching to the atypical antipsychotic drugs. Subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI), and the Positive and Negative Syndrome Scale (PANSS) was used to measure psychopathology. Results: The proportion of the patients who experienced improved subjective sleep quality was significantly higher in the elderly than in the middle-aged group. Logistic-regression analysis revealed that the improvement in subjective sleep quality through administration of atypical antipsychotic drugs was predicted by increased age, daytime dysfunction, and longer sleep latency at baseline. Conclusion: These results demonstrate that atypical antipsychotic drugs are beneficial to the quality of sleep in elderly patients with schizophrenia.