Parasomnia overlap disorder with adolescent-onset presumed REM sleep behavior disorder converting to Parkinson's disease after 48 years

Abstract

Background: It is now recognized that the vast majority of individuals with typical RBD will develop a synucleinopathy; usually 11-16 years after symptom onset. Parasomnia Overlap Disorder (POD) with adolescent-onset dream enactment behavior with phenoconversion to neurodegenerative disease after a long latency has not been previously described.

Patient: We present a case of a 65-year-old man with presumptive POD who had co-morbid childhood onset sleep walking and adolescent-onset dream enactment behavior beginning at age 17, with subsequent evolution to an increasingly troublesome REM sleep behavior disorder (RBD) at age 64 with Parkinson's Disease (PD) developing a year later.

Results: Polysomnography performed at age 64 was consistent with a diagnosis of RBD. Dream enactment behavior preceded PD diagnosis by at least 48 years. Our case represents the youngest reported RBD case who developed PD.

Conclusions: We report the first case of adolescent onset, presumed RBD in the context of presumptive POD developing neurodegenerative disease. Adolescent-onset RBD may have similar prognostic implications as typical RBD, where future phenoconversion to a synucleinopathy is expected.

Keywords: Parasomnia overlap disorder; Parkinson's disease; REM sleep behavior disorder.