Key Points
Question Are circadian abnormalities in older adults associated with an increased risk of developing Parkinson disease over time?
Findings In this longitudinal study of 2930 community-dwelling older men without Parkinson disease at baseline, the risk of incident Parkinson disease increased significantly with decreasing circadian amplitude, mesor, or robustness. Participants in the lowest quartile for these measures had approximately 3 times the risk of developing Parkinson disease compared with those in the highest quartile.
Meaning Circadian rhythm disruption in elderly individuals may represent an important prodromal feature for Parkinson disease, and future studies should test whether circadian disruption could also be a risk factor for Parkinson disease and whether strategies to improve circadian function affect the risk of Parkinson disease.