Risk stratification for REM sleep behavior disorder in patients with Parkinson’s disease: A PRISMA-compliant meta-analysis and systematic review

This study aimed to compare whether the characteristics of Parkinson's disease (PD) patients between probably rapid eye movement sleep behavior disorder (RBD) and confirmed RBD versus non-RBD are differing using a meta-analytic approach. We systematically searched PubMed, EmBase, and the Cochrane library for eligible studies throughout October 2018 in this meta-analysis. The clinical characteristics of PD patients presented with probably RBD, confirmed RBD, or non-RBD were analyzed. The pooled odds ratios and weighted mean differences with corresponding 95 % confidence intervals were calculated for categories and continuous data, respectively. All the pooled analyses were conducted using random-effects model. Forty-seven studies recruited a total of 8019 PD patients were included in the final meta-analysis. The summary results indicated significant differences between probable RBD and non-RBD for PD duration, levodopa dosage daily, Hoehn-Yahr stage, UPDRS-III, UPDRS-motor score, UPDRS activity of daily living, Epworth Sleepiness scale, male percentage, dyskinesia, orthostatic hypotension, constipation, and fluctuations present. Moreover, confirmed RBD versus non-RBD showed significant differences for age, PD duration, levodopa dosage daily, Mini-Mental State Examination, Hoehn-Yahr stage, UPDRS-motor score, Epworth Sleepiness scale, male percentage, dyskinesia, hallucination, insomnia, dementia, orthostatic hypotension, falls, and fluctuations present. Furthermore, the difference of confirmed RBD versus non-RBD was significantly elderly than probable RBD versus non-RBD. Moreover, PD patients with confirmed RBD with lower Mini-Mental State Examination as compared with probable RBD corresponding PD patients without RBD. In addition, PD patients with confirmed RBD versus probable RBD was associated with high Hoehn-Yahr stage as compared with non-RBD. Finally, patients with confirmed RBD with high incidence of insomnia as compared with probable RBD corresponding PD patients without RBD. The results provide the comprehensive differences in the patients' characteristics among probable RBD, confirmed RBD, and non-RBD in PD patients.