Inter-rater reliability for identification of REM sleep in Parkinson's disease

Recently described functional connections between basal ganglia and brainst em circuits provide a neurobiologic basis for the absence of REM sleep aton ia in Parkinson's disease (PD), However, identifying atypical REM sleep in PD may be problematic. Reliable sleep staging has never been demonstrated i n such patients. In this study, 3 experienced scorers independently evaluat ed overnight polysomnograms from 10 (PD) patients. Results indicated good a greement for distinguishing REM from NREM sleep and waking. Reliable differ entiation among NREM stages was more difficult to achieve. The results sugg est that, despite suspension of REM sleep atonia accompanying PD, trained s corers can distinguish REM from wakefulness and NREM sleep.