
Four early non-motor clues that may precede Parkinson’s by years
Non-motor signs can appear years before Parkinson’s motor symptoms. Loss of smell may begin up to about 20 years before diagnosis; REM sleep behavior disorder markedly increases future risk (many develop Parkinson’s within 5–10 years); constipation and orthostatic hypotension are also early markers with varying strength. These signs aren’t diagnostic alone, but multiple markers or a family history warrant medical evaluation, and smell tests are available through research programs.






