Validation of a polysomnographic score for REM sleep behavior disorder

Sleep. 2005 Aug 1;28(8):993-7. doi: 10.1093/sleep/28.8.993.


Study objectives: Rapid eye movement (REM) sleep behavior disorder (RBD) was described more than 2 decades ago, but only 1 report on 5 patients and 5 normal subjects has tested the effectiveness of a method by which relevant polysomnographic findings can be quantified. We sought to validate this method in a larger sample of patients and control subjects.

Design: Cross-sectional.

Setting: Academic hospital.

Interventions: A clinician interviewed 17 patients at risk for RBD secondary to neurodegenerative disorders and 6 controls to assess whether RBD was present by history. Bed partners completed a questionnaire that quantified RBD symptom severity. From 2 consecutive nocturnal studies in each patient, 2 different polysomnographic RBD scores were generated: the percentage of 30-second REM epochs with at least 15 seconds of tonically maintained electromyographic activity, and the percentage of 3-second REM mini-epochs that contained phasic electromyographic bursts.

Measurements and results: The tonic and phasic measures, combined together, were higher in patients with clinical determinations of probable or possible RBD (n=9) than in patients judged unlikely to have RBD (n=4, P = .023). The overall polysomnographic measure correlated with the symptom scores (rho = 0.42, P = .048). Specific polysomnographic RBD measures on night 1 correlated highly with those on night 2 (rho > 0.70, P < .0001).

Conclusions: This quantitative method to assess the severity of RBD polysomnographic features appears to be both valid and reliable in patients at risk for RBD because of neurodegenerative disorders.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.
  • Validation Study

MeSH terms

  • Aged
  • Cross-Sectional Studies
  • Electromyography
  • Female
  • Health Status
  • Humans
  • Male
  • Middle Aged
  • Polysomnography / methods*
  • REM Sleep Behavior Disorder / diagnosis*
  • Reproducibility of Results
  • Surveys and Questionnaires