REM sleep behavior disorder (RBD) is a novel type of Parasomnias characterized by abnormal behavioral manifestations during REM sleep. RBD affects 0.4-0.5% of the elderly population with a typical age of onset in 50s-60s. RBD presents with a spectrum of dreamenacting behavioral manifestations, including sleep shouting, fisting, kicking or falling out of bed with a high prevalence of sleep-related injuries to themselves or/and bed-partners.
Accumulating evidences suggests that idiopathic RBD (iRBD) is an integrated part of disease progress in α-synucleinopathy neurodegeneration, such as Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). Longitudinal clinical studies suggests that the estimated 5-year risk of developing any neurodegenerative disorder in iRBD patients range from 8.5%-38%, which increase to 38%-65% at around 10- year follow-up