Author Response: In Vivo Distribution of α-Synuclein in Multiple Tissues and Biofluids in Parkinson Disease

Regarding the sensitivity of IHC aSyn methods in participants with idiopathic REM sleep behavioral disorder (RBD), we agree that these are encouraging for the early detection of α-synucleinopathies but point out that not all participants with PD or dementia with Lew bodies (DLB) have RBD and those who do tend to have more widespread and severe aSyn brain histopathology as compared with those without RBD.6 This may also be true for prodromal participants with and without RBD.