Comparative study of sleep disorder and its effect on health-related quality of life in patients with Parkinson's disease between early-stage and middle- and late-stages

Objective To compare the characteristics of sleep disorder and its effect on health-related quality of life in patients with Parkinson's disease (PD) between early-stage and middle- and late-stages. Methods One hundred and fifty-one patients collected in our hospital from September 2014 to May 2016 were divided into PD patients at early stage (grading 1-2, n=82) and PD patients at middle- and late-stages (grading 3-5, n=69) according to Hoehn-Yahr (H-Y) grading. Mini-Mental Status Examination (MMSE), Hamilton Anxiety Rating (HAM-A) scale and Hamilton Depression Rating (HAM-D) scale, Unified Parkinson's Disease Rating Scale III (UPDRSIII), H-Y grading, Non-motor Symptoms Questionnaire (NMS) and Parkinson's Disease Sleep Scale (PDSS) were used to evaluate cognition states, emotion states, movement functions, disease severity, nonmotor symptoms and sleep disturbances of patients from the two groups. The 39-item Parkinson's Disease Questionnaire (PDQ-39) was used to evaluate the quality of life of PD patients. Results The incidence of sleep disorder in PD patients at middle- and late-stages was significantly higher than that in PD patients at early stage (P<0.05), and the total scores of PDSS in PD patients at middle- and late-stages were significantly lower than those in PD patients at early stage (P<0.05). Fragmented sleep (31.7% and 47.8%) and excessive sleepiness at daytime (38.7% and 43.5%) were the most common problems in patients from the two groups. Sleep disorder was negatively correlated with duration, and scores of HAM-A, HAM-D, UPDRSIII and H-Y grading, while it was positively correlated with MMSE scores in patients from the two groups (P<0.05). Sleep disorder was negatively correlated with NMS scores and daily levodopa equivalent dose in PD patients at middle- and late-stages (P<0.05). Multivariate regression analysis indicated that PDSS total scores were negatively correlated with HAMD scores and positively correlated with MMSE scores in all patients (P<0.05). PDSS total scores were negatively correlated with duration in PD patients at middle- and late-stages (P<0.05). Sleep disorder was negatively correlated with total scores of PDQ39, mobility, activity of daily living, communication ability and body discomfort in PD patients at middle- and late-stages (P<0.05). Conclusions The quality of sleep disorder in PD patients at middle- and late-stages is worse than that in PD patients at early stage, and the quality of life is further reduced than that in PD patients at early stage. The course of disease has a great influence in sleep disorder of PD patients. Key words: Parkinson's disease; Sleep disorder; Quality of life