REM sleep behaviour disorder: the importance of early identification in primary care

REM (rapid eye movement) sleep behaviour disorder (RBD) is characterised by vivid dreams and dream enactment behaviour such as kicking, shouting, and punching.1 It can result in injuries to the person with RBD and their bed partner, and is associated with reduced quality of life and severely disrupted sleep. It is important to recognise potential RBD because it is also strongly associated with neurodegenerative disease (NDD): RBD affects approximately 50% of people with Parkinson’s disease (PD), 80% of people with dementia with Lewy bodies (DLB), and almost 100% of people with multiple system atrophy (MSA).2,3 RBD is also an early sign of neurodegenerative disease and can occur in otherwise healthy individuals when it is known as idiopathic or isolated RBD (iRBD). This isolated form is associated with an 80–90% risk of progression to an NDD, such as PD or DLB, within 10 years of first diagnosis.3 iRBD commonly presents in males >50 years and is estimated to occur in 2% of the general population.4 Thus, identifying iRBD provides a rare opportunity to modify future risk of neurodegeneration and there are anticipated opportunities for patients with iRBD to enrol in neuroprotective drug trials to prevent progression to an overt NDD.