Utility of the REM sleep behavior disorder screening questionnaire (RBDSQ) in Parkinson's disease patients

Objective: We evaluated the usefulness of the REM sleep behavior disorder (RBD) screening questionnaire (RBDSQ) among patients with Parkinson's disease (PD). Methods: Forty-five patients with PD were evaluated (22 male and 23 female, 72.9 +/- 9.1 years old). After patients completed the RBDSQ we conducted interviews regarding RBD symptoms and performed polysomnographic examinations on the subjects. We then compared RBDSQ scores among the following groups: PD with RBD (n = 19), PD without RBD (n = 26), and idiopathic RBD (n = 31,22 male and 9 female, 67.8 +/- 6.5 years old), and estimated the cut-off score for an RBD diagnosis. Results: RBDSQ scores in PD with RBD and idiopathic RBD groups were similar and higher than those in the PD without RBD group (PD with RBD: 7.2 +/- 1.9, idiopathic RBD: 7.9 +/- 2.8, PD without RBD: 2.9 +/- 1.6). Cronbach's alpha for RBDSQ sub-scores was 0.73, suggesting a fair internal consistency. A receiver-operator characteristics curve revealed that a total score of 6 points on the RBDSQ represented the best cut-off value for detecting RBD (sensitivity = 0.842, specificity = 0.962). Conclusion: RBDSQ could be a useful tool for the screening of RBD in PD patients. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.