Gout and open-angle glaucoma risk in a veteran population

Purpose A history of gout, arthritis due to hyperuricemia, has been associated with decreased risk for neurodegenerative diseases such as Parkinson's disease. We performed a population-based case-control study in the US Department of Veterans Affairs (VA) medical centers nationwide to assess if gout or hyperuricemia is similarly associated with the ocular neurodegenerative condition glaucoma. Methods We used ICD-9 codes to identify a nationwide cohort of patients examined at VA healthcare eye clinics between 2000 and 2015 with a diagnosis of open-angle glaucoma (OAG) or of glaucoma suspect. We used incidence density matching to choose controls. We used multivariable logistic regression to examine associations between a history of gout and uric acid (UA) levels on relative risk of OAG or glaucoma suspect. Results There were 1,144,428 OAG or glaucoma suspect cases and 1,144,428 matched controls. Veterans with a history of gout had a small significant decreased risk of OAG compared to controls (ORadjusted(adj) = 0.985, 95% CI: 0.974-0.996). Treated gout was similarly associated with small decreased risk (ORadj = 0.963, 95% CI: 0.950-0.976). A small subset of patients (11.9% of cases and 13.2% of controls) had UA labs available; veterans with the highest median UA levels (> 7.29 mg/dL) did not have statistically significant differences in relative OAG risk (ORadj = 1.014, 95% CI: 0.991-1.036). Conclusion Prospective research in other cohorts is needed to confirm our findings in veterans suggesting a history of gout is associated with a small decreased relative risk of glaucoma.