Assessment of sleep quality using cardiopulmonary coupling analysis in patients with Parkinson's disease

OBJECTIVES: To assess the sleep quality of patients with Parkinson's disease (PD) and evaluate the effect of cardiopulmonary coupling (CPC) analysis on sleep quality and its correlation with subjective complaints in patients with PD. METHODS: Our study included 42 patients with PD and 30 healthy controls. CPC analysis and the Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the sleep quality of subjects. RESULTS: High‐frequency coupling (HFC) and sleep efficiency were significantly lower in the PD than in the control group, whereas very low‐frequency coupling (VLFC) and sleep latency were significantly higher in the PD than in the control group. PSQI scores were significantly higher in the PD than in the control group (all p < .05). The PSQI score showed a negative correlation with the HFC ratio in the PD group (r = −.478, p = .001). Factors related to the occurrence of PD with poor sleep quality were the unified Parkinson's disease rating scale (UPDRS) score and nocturia. CONCLUSIONS: The sleep quality of patients with PD was generally decreased. CPC analysis can reflect the subjective sleep quality of patients with PD and serve as an effective sleep monitoring tool.