Gout and risk of Parkinson disease: A prospective study

BACKGROUND: Several reports suggest that higher levels of serum uric acid are associated with a lower risk of Parkinson disease (PD). None of these studies, however, evaluated the potential association between gout, a condition characterized by hyperuricemia, and the risk of PD. OBJECTIVE: To estimate prospectively the association between gout diagnosis and the risk of PD. METHODS: We conducted a case-control study nested in the General Practice Research Database, a computerized database that gathers information on more than 3 million Britons followed up by their general practitioners. PD cases occurring between January 1995 and December 2001 were identified, and matched with up to 10 controls by sex, age, practice, and start of follow-up. We obtained information on history of gout and use of anti-gout medication using the computerized medical records. RESULTS: During the study period, we identified 1,052 PD cases and 6,634 controls. Individuals with previous history of gout had a lower risk of developing PD (OR 0.69, 95% CI 0.48, 0.99). This association was evident among men (OR 0.60, 95% CI 0.40, 0.91) but not among women (OR 1.26, 95% CI 0.57, 2.81; p for interaction: 0.11). Initiation of anti-gout medication was associated with a lower risk of PD (OR 0.57, 95% CI 0.19, 1.70). CONCLUSION: Gout is associated with a lower risk of Parkinson disease (PD). Our findings provide additional support for a potential link between uric acid and PD. Further research is required to explore a potential effect modification by sex.