title: REM sleep behaviour disorder is associated with worse quality of life and other non-motor features in early Parkinson's disease.
abstract: BACKGROUND
  Concomitant REM sleep behaviour disorder (RBD) is commonly observed in patients with Parkinson's disease (PD). Although the brainstem structures responsible for the symptoms of RBD correspond to the premotor stages of PD, the association of RBD with motor and non-motor features in early PD remains unclear.
  
  
  METHODS
  The study evaluated 475 patients with PD within 3.5 years of diagnosis for the presence of probable RBD (pRBD) using the REM Sleep Behaviour Disorder Screening Questionnaire (RBDSQ). A neurologist and a trained research nurse carried out evaluation of each participant blinded to the results of the RBDSQ. Standardised rating scales for motor and non-motor features of PD, as well as health-related quality of life measures, were assessed. Multiple linear and logistic regression analyses were used to determine the relationship between pRBD and a variety of outcomes, controlling for confounding factors.
  
  
  RESULTS
  The overall frequency of pRBD was 47.2% (95% CI 42.7% to 51.9%). None of the patients had a previous diagnosis of RBD. Patients with PD and concomitant pRBD did not differ on motor phenotype and scored comparably on the objective motor scales, but reported problems with motor aspects of daily living more frequently. Adjusted for age, sex, disease duration and smoking history, pRBD was associated with greater sleepiness (p=0.001), depression (p=0.001) and cognitive impairment (p=0.006).
  
  
  CONCLUSIONS
  pRBD is common and under-recognised in early PD. It is associated with increased severity and frequency of non-motor features, poorer subjective motor performance and a greater impact on health-related quality of life.
authors.affiliation: Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Oxford, UK.
authors.forename: Michal
authors.initials: M
authors.lastname: Rolinski
authors.forename: Konrad
authors.initials: K
authors.lastname: Szewczyk-Krolikowski
authors.forename: Paul R
authors.initials: PR
authors.lastname: Tomlinson
authors.forename: Kannan
authors.initials: K
authors.lastname: Nithi
authors.forename: Kevin
authors.initials: K
authors.lastname: Talbot
authors.forename: Yoav
authors.initials: Y
authors.lastname: Ben-Shlomo
authors.forename: Michele Tm
authors.initials: MT
authors.lastname: Hu
mesh_terms: D000368:Aged; D003072:Cognition Disorders / Q000453:epidemiology / Q000503:physiopathology / Q000523:psychology; D015331:Cohort Studies; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D010300:Parkinson Disease / Q000150:complications* / Q000503:physiopathology / Q000523:psychology*; D011788:Quality of Life; D020187:REM Sleep Behavior Disorder / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology; D011795:Surveys and Questionnaires
keywords: PARKINSON'S DISEASE; QUALITY OF LIFE; SLEEP DISORDERS