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

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.