In adults with REM sleep behavior disorder, what is a recommended next step?

• A. Immediate antipsychotic therapy
• B. No further evaluation
• C. Sleep study not indicated
• D. Evaluation for underlying neurodegenerative disease

Answer: (D)

RBD in adults often serves as an early sign of an underlying neurodegenerative process, particularly synucleinopathies such as Parkinson disease, dementia with Lewy bodies, or multiple system atrophy. Because of this strong association, the next step after identifying REM sleep behavior disorder is to evaluate for an underlying neurodegenerative disease and arrange ongoing neurological follow-up. This approach helps detect emerging motor, cognitive, or autonomic symptoms early and allows for appropriate counseling and management. Starting antipsychotic therapy would not address the underlying risk and can worsen REM-related symptoms, and while a sleep study is important for confirming the diagnosis, the key immediate action is to assess for potential neurodegenerative disease.