Rapid eye movement sleep behaviour disorder in young- and older-onset Parkinson disease: a questionnaire-based study

Rapid eye movement sleep behavior disorder (RBD) is common in Parkinson disease (PD).

To determine the frequency of clinically probable RBD (cpRBD) in young-onset (21 to < or =40 years; YOPD) and older-onset PD (>40 years; OOPD) and characterize its pattern.

A total of 156 patients with PD (YOPD-51, OOPD-105) were clinically examined and the presence of RBD was diagnosed using the minimal criteria for diagnosis of RBD (International Classification of Sleep Disorders, ICSD-1). RBD screening questionnaire based on the minimal criteria was used. The bed-partners were also interviewed with Mayo sleep questionnaire. Other scales included Unified Parkinson Disease Rating Scale part III (UPDRS III), Hoehn & Yahr stage, Mini Mental Status Examination, Pittsburgh Sleep Quality Index, Parkinson Disease Sleep Scale, Epworth Sleep Scale, Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale.

cpRBD was diagnosed in 30 (19.2%) patients, majority being OOPD rather than YOPD (86.7% vs. 13.3%; P=0.01). The frequency of RBD was significantly higher (P=0.016) in OOPD (24.8%) compared to those with YOPD (7.8%). Most often (72.4%) RBD occurred after the onset of parkinsonian symptoms. RBD was independently associated with higher global PSQI scores, total ESS scores and total PDSS scores after adjusting for the effects of age, gender, Hoehn & Yahr stage and duration of illness.

Patients with RBD were older with later-onset motor symptoms, a more advanced stage, poorer sleep quality, and more frequent daytime sleepiness. Older-onset PD had a higher frequency of RBD than young-onset PD.