Multiple comorbid sleep disorders adversely affect quality of life in Parkinson's disease patients

Abstract

Sleep disorders are common non-motor symptoms in patients with Parkinson's disease (PD). The characteristics and impact of multiple comorbid sleep disorders remain to be elucidated. Our goal was to investigate the characteristics of various sleep disorder comorbidities, and their association with motor complications and the impact on the quality of life in PD patients. In this multicenter, observational, cross-sectional study, data concerning the clinical characteristics of complicated sleep disorders were collected from PD patients treated at 40 different hospitals in Shanghai. Sleep disorders were evaluated using the PD Sleep Scale-2, Epworth Sleepiness Scale, Rapid Eye Movement Sleep Behavior Disorder Questionnaire-Hong Kong, and the International Restless Legs Scale. Among the 1006 subjects evaluated, 77.53% exhibited signs of sleep disorders, and most had multiple sleep disorders (n = 502, 49.9%). A smaller percentage of patients with sleep disorders had a single disorder (n = 278, 27.6%). Furthermore, an increased number of sleep disorders, including nighttime problems, excessive daytime sleepiness, rapid eye movement sleep behavior disorder, and restless legs syndrome was a significant contributor to a poor quality of life (β = 4.33, CI: 3.33-5.33, P for trend <0.001), even when controlling for multiple factors. Moreover, motor complications partially mediated this relationship (indirect effect: β = 0.355, 95% boot CI: 0.134, 0.652).Our study showed that a large proportion of PD patients suffer from multiple comorbid sleep disorders, which greatly decreases the quality of life in PD patients and is partially mediated by motor complications.

Keywords: Parkinson's disease.

Fig. 1. Prevalence and overlap of sleep disorders in patients with PD.

EDS excessive daytime sleepiness, pRBD probable rapid eye movement sleep behavior disorder, RLS restless legs syndrome.

Fig. 2. Motor complications partially mediated the effect of multiple comorbid sleep disorders on quality of life.

a Stratification analyses of positive associations between an increased number of sleep disorders and quality of life by motor complications status. Number of sleep disorders (0–4; nighttime problems, EDS, pRBD, and RLS). b Motor complications as a mediator between an increased number of sleep disorders and quality of life. All associations were adjusted for sex, age, disease duration, modified HY stage, UPDRS part III, NMSS, MMSE, L-dopa medication status, dopamine agonist medication status, and levodopa equivalent daily dose.