Identifizierung der REM-Schlaf-Verhaltensstörung mittels REM-Sleep-Behavior-Disorder-Screening-Questionnaire

Rapid eye movement sleep behavior disorder is a rare and insufficiently investigated disease. Present data suggest that RBD represents a risk factor or an early clinical manifestation of an evolving neurodegenerative disorder, mostly an alpha-synucleinopathy. In such case REM sleep behavior disorder precedes neurodegenerative disorders for many years. On present knowledge video-polysomnography is required to confirm the diagnosis of RBD, which is obviously unsuitable to be used for screening patients on a broad basis. Therefore, no precise data on the prevalence of RBD in the general population are available. According to previous estimates, prevalence has been assumed to range from 0,5 to 8,9%. The need of a simple and economic tool for diagnosis of RBD is therefore important. The REM sleep behavior disorder screening questionnaire has been validated to be helpful in this purpose. The objective of this research was to investigate the RBDSQ's usefulness as screening tool in order to define the prevalence of RBD. Between October 2008 and October 2010 the RBDSQ was applied to subjects in the outpatient and inpatient setting. Inclusion criteria were age between 50 and 75 years at screening time and a signed written informed consent form. Every subject had to answer the questions without help. We analyzed 551 questionnaires. RBD prevalence estimation calculated by using the RBDSQ ranged between 22 – 28% and clearly exceeds previously known data. A video-polysomnography of five subjects performed on a random basis confirmed the diagnosis of one RBD, one obstructive sleep apnoe syndrome, one periodic limb movement disorder and one insomnia. Furthermore another case with clinically compatible RBD diagnosis was revealed but did not fulfill all RBD criteria. The hit rate for clinical RBD by RBDSQ seems likely to be affected by medication, secondary diseases and further confounders. The present work shows that the REM sleep behavior disorder screening questionnaire is capable of identifying subjects with RBD, however other disorders seem to be detected as well. A video-polysomnography is still indispensable in order to verify the RBDSQ's results.