REM sleep behavior disorder was associated with Parkinson's disease: a community-based study.

<bold>Background: </bold>Our study was aimed to validate a modified RBD (REM sleep behavior disorder) single question (RBD1Q-C), study the prevalence of probable RBD (pRBD) in a rural community based on RBD1Q-C and investigate the association between pRBD and Parkinson's disease (PD).<bold>Methods: </bold>The validation study of RBD1Q-C included 32 Chinese participants (14 idiopathic RBD patients and 18 controls). All participants underwent a polysomnogram (PSG). We then conducted a door-to-door survey to estimate the prevalence of pRBD assessed by RBD1Q-C, and its association with PD among 19614 residents who lived in Malu community of Shanghai, China.<bold>Results: </bold>RBD1Q-C demonstrated a high sensitivity of 100%, a moderate specificity of 55.6%. The agreement between RBD1Q-C and PSG-based RBD diagnosis was good (k = 0.552). PPV of the RBD1Q-C was 63.6% and NPV was 100%. The prevalence of pRBD in Malu community was 4.9%. In people over 50 years old, presence of pRBD was significantly associated with increased risk of having PD (odds ratio = 2.61, 95% CI: 1.56-4.39).<bold>Conclusion: </bold>RBD1Q-C was shown to be a useful screening tool. Based on the RBD1Q-C, we found that pRBD was not rare in Chinese rural population and associated with odds of PD, calling for more attention from patients, caregivers and physicians. [ABSTRACT FROM AUTHOR]