To study the clinical features of excessive daytime sleepiness (EDS) in patients with Parkinson′s disease (PD) complicated with chronic kidney disease (CKD), and assess the effect of renal function on EDS of patients with PD.

60 patients with PD complicated with CKD were enrolled as the subjects. According to the CKD stage, Epworth sleepiness scale (ESS) and other relevant scales were used to assess the clinical features of PD patients in order to evaluate the influence of renal function on EDS of the PD patients. Multiple-variables linear regression was also applied for analyzing factors involved in EDS of PD patients so as to determine the predictive factors influencing EDS.

Between the groups of PD patients who had EDS complicated with CKD, the differences in demographic data were not statistically significant. The incidence rate of EDS was 51.7% in the PD patients complicated with CKD. With decline of renal function of patients, the ESS score (F=4.578, P=0.001), Pittsburgh sleep quaiity index (PSQI) (F=3.399, P=0.025), unified Parkinson disease rating scale Ⅲ (UPDRSⅢ) score (F=3.745, P=0.015), and UPDRS Ⅱ score (F=3.244, P=0.030) all increased, while Parkinson disease quality of life questionnaire-39 (PDQL-39) score (F=0.792, P=0.279), the multiple sleep latency test (MSLT) time (F=5.672, P=0.001), and levodopa equivalents (LDE) (F=5.785, P=0.001) gradually reduced; and the patients′ quality of sleep at night, motor function, ability of daily life, and quality of life were also reduced accordingly.

EDS was common in PD patients complicated with CKD, which was not only related with pathological changes of the disease itself and disorders of the sleep centre regulation, but also with the poor quality of sleep at night as well as application of the anti-PD drugs. CKD may be a risk factor for EDS of PD patients.