Chronic Musculoskeletal Pain and Risk of Incident Parkinson's Disease: A 13-Year Longitudinal Study

Background: Chronic musculoskeletal pain often co-occurs with Parkinson's disease (PD); however, whether individuals with chronic pain have a higher risk of developing PD is unclear. Objectives: To investigate the associations between chronic pain and incident risk of three neurodegenerative parkinsonism categories including PD, multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Methods: This study included 355,890 participants (mean [standard deviation] age, 56.51 [8.07] years, 48.40% male) who did not have parkinsonism at baseline from a population-based cohort. Musculoskeletal pain in the hip, neck/shoulder, back, knee, or “all over the body” was assessed. Chronic pain was defined if pain lasted ≥3 months. Participants were categorized into four groups: no chronic pain, having one or two, three or four sites, and pain “all over the body.” The diagnosis of PD, MSA, and PSP used self-reports, hospital records, and death registries. Multivariable-adjusted Cox regression was performed for the analyses. Results: Over a median follow-up of 13.0 years, 2044 participants developed PD, 77 participants developed MSA, and 126 participants developed PSP. In multivariable analyses, there was a dose–response relationship between number of chronic pain sites and incident risk of PD (hazard ratio, 1.15; 95% confidence interval, 1.07–1.23). Participants with one or two pain sites and three or four pain sites had an 11% and 49% increased risk of developing PD, respectively. There were no associations between chronic pain and MSA or PSP. Conclusions: Chronic musculoskeletal pain was independently associated with PD, suggesting that chronic pain could be used to identify individuals at risk of developing PD.