Prevalence of idiopathic REM behavior disorder: a systematic review and meta-analysis

International audienceStudy objectives: To provide an overall estimate of the prevalence of idiopathic REM Sleep Behavior Disorder (iRBD). Methods: Two investigators have independently searched the PubMed and Scopus databases for population-based studies assessing the prevalence of iRBD. Data about type of diagnosis (polysomnographic diagnosis, defined iRBD [dRBD]; clinical diagnosis, probable RBD [pRBD]), continent, age range of the screened population, quality of the studies, sample size, screening questionnaires and strategies have been gathered. A random effect model was used to estimate the pooled prevalence. Heterogeneity was investigated with subgroup analysis and meta-regression. Results: From 857 articles found in the databases, 19 articles were selected for the systematic review and meta-analysis. According to the type of diagnosis, five studies identified dRBD cases given a pooled prevalence of 0.68% (95%CI 0.38-1.05) without significant heterogeneity (Cochran's Q p=0.11; I 2 = 46.43%). Fourteen studies assessed the prevalence of pRBD with a pooled estimate of 5.65% (95%CI 4.29-7.18) and a significant heterogeneity among the studies (Cochran's Q p