Feng SH, Chuang HJ, Yeh KC, et al. - Researchers used Taiwan’s Longitudinal Health Insurance Database 2005 in this retrospective cohort analysis to determine if there exists a higher risk of developing Parkinson disease (PD) in patients suffering from osteoarthritis (OA). The OA group comprised 33,360 patients who were 50-64 years old and had OA in 2002-2005. The comparison group included 33,360 age- and gender-matched, randomly sampled individuals without OA. The impact of having OA on patients’ subsequent risk of PD was estimated using multivariable Cox proportional-hazard regression analysis. Findings revealed an association of OA with an elevated risk of developing PD.