Clinical Association between Gout and Parkinson's Disease: A Nationwide Population-Based Cohort Study in Korea

Background and Objectives: This retrospective cohort study aimed to investigate the association between gout and Parkinson's disease (PD) in Korea. Materials and Methods: Overall, 327,160 patients with gout and 327,160 age- and sex-matched controls were selected from the Korean National Health Insurance Service (NHIS) database. PD incidence was evaluated by reviewing NHIS records during the period from 2002 to 2019. Patients with a diagnosis of gout (International Classification of Diseases-10 (ICD-10), M10) who were prescribed medications for gout, including colchicine, allopurinol, febuxostat, and benzbromarone for at least 90 days were selected. Patients with PD who were assigned a diagnosis code (ICD-G20) and were registered in the rare incurable diseases (RID) system were extracted. Results: During follow-up, 912 patients with gout and 929 control participants developed PD. The incidence rate (IR) of overall PD (per 1000 person-years) was not significantly different between both groups (0.35 vs. 0.36 in gout and control groups, respectively). The incidence rate ratio (IRR) was 0.98 (95% CI: 0.89-1.07). The cumulative incidence of PD was not significantly different between the groups. No association between gout and PD was identified in univariate analysis (HR = 1.00, 95% CI: 0.91-1.10, p = 0.935). HR increased significantly with old age (HR = 92.08, 198, and 235.2 for 60-69 years, 70-79 years, and over 80 years, respectively), female sex (HR = 1.21, 95% CI: 1.07-1.37, p = 0.002), stroke (HR = 1.95, 95% CI: 1.76-2.16, p < 0.001), and hypertension (HR = 1.16, 95% CI: 1.01-1.34, p = 0.04). Dyslipidemia exhibited an inverse result for PD (HR = 0.6, 95% CI: 0.52-0.68, p < 0.001). Conclusions: This population-based study did not identify an association between gout and PD. Age, female sex, stroke, and hypertension were identified as independent risk factors for PD, and dyslipidemia demonstrated an inverse result for PD.