The COSP-RBD Study: Concussions and Contact Sports in RBD vs Controls

The goal of this observational study is to investigate concussions and contact sports practices in REM sleep behaviour disorder (RBD). The main questions it aims to answer are: * What is the proportion of patients with RBD that have a history of concussions or exposure to contact sports? * Is this proportion higher to that in control patients without a diagnosis of RBD? Participants will undergo an interview with a sleep medicine specialist to answer questions about history of concussions and contact sports practices. Researchers will compare an RBD group and a control group (without RBD) to see if the proportion of concussions and exposure to contact sports differ.