title: Occurrence and clinical correlates of REM sleep behaviour disorder in patients with Parkinson's disease over time.
abstract: OBJECTIVE
  To examine the occurrence and clinical and demographic correlates of REM sleep behaviour disorder (RBD) in patients with Parkinson's disease (PD) in a community-based cohort over 8 years.
  
  
  METHODS
  231 patients with PD were included in a population-based prevalence study in 1993. Patients were then followed prospectively and reexamined after 4 and 8 years. Semi-structured interviews for information on clinical and demographic data were applied at all study visits. Standardised rating scales of parkinsonism, depression and cognitive impairment were used. The diagnosis of probable RBD (pRBD) was based on a sleep questionnaire. Proportional-odds ordinal logistic regression models for clustered data were used to study the relationship between pRBD and various demographic and clinical variables.
  
  
  RESULTS
  231 patients were evaluated for RBD in 1993 and, after 4 and 8 years, 142 and 89 patients, respectively, were available for re-evaluation. The frequency of pRBD varied from 14.6% to 27% during the study period. Probable RBD was related to male gender, higher dopaminergic treatment and less severe parkinsonism.
  
  
  CONCLUSIONS
  We found that the frequency of pRBD varied over time and that it is associated with male gender, less parkinsonism and higher levodopa equivalent dose. Our findings indicate that dopaminergic therapy may contribute to the expression of RBD and that RBD is symptomatic in earlier stages of PD.
authors.affiliation: The Norwegian Centre for Movement Disorders, Stavanger, Norway, PB 8100, N-4068 Stavanger, Norway. gjmi@sus.no
authors.forename: M D
authors.initials: MD
authors.lastname: Gjerstad
authors.forename: B
authors.initials: B
authors.lastname: Boeve
authors.forename: T
authors.initials: T
authors.lastname: Wentzel-Larsen
authors.forename: D
authors.initials: D
authors.lastname: Aarsland
authors.forename: J P
authors.initials: JP
authors.lastname: Larsen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000978:Antiparkinson Agents / Q000008:administration & dosage / Q000009:adverse effects; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018491:Dopamine Agonists / Q000008:administration & dosage / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage / Q000009:adverse effects; D008137:Longitudinal Studies; D008297:Male; D009460:Neurologic Examination / Q000187:drug effects; D009483:Neuropsychological Tests; D009664:Norway; D010300:Parkinson Disease / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D020734:Parkinsonian Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D011446:Prospective Studies; D020187:REM Sleep Behavior Disorder / Q000175:diagnosis / Q000453:epidemiology*; D012737:Sex Factors
chemical_list: D000978:Antiparkinson Agents; D018491:Dopamine Agonists; D007980:Levodopa