Serum uric acid levels and the risk of type 2 diabetes: a prospective study.

PURPOSE: To evaluate the impact of serum uric acid levels on the future risk of developing type 2 diabetes independent of other factors.

METHODS: We used prospective data from the Framingham Heart Study original (n=4883) and offspring (n=4292) cohorts to examine the association between serum uric acid levels and the incidence of diabetes. We used Cox proportional hazards models to estimate the relative risk of incident diabetes adjusting for age, sex, physical activity, alcohol consumption, smoking, hypertension, body mass index, and blood levels of glucose, cholesterol, creatinine, and triglycerides.

RESULTS: We identified 641 incident cases of diabetes in the original cohort and 497 cases in the offspring cohort. The incidence rates of diabetes per 1000 person-years for serum uric acid levels <5.0, 5.0-5.9, 6.0-6.9, 7.0-7.9 and ≥8.0 mg/dL were 3.3, 6.1, 8.7, 11.5, and 15.9, respectively, in the original cohort; and 2.9, 5.0, 6.6, 8.7, and 10.9, respectively, in the offspring cohort (P-values for trends <.001). Multivariable relative risks per mg/dL increase in serum uric acid levels were 1.20 (95% confidence interval; 1.11-1.28) for the original cohort and 1.15 (95% confidence interval; 1.06-1.23) for the offspring cohort.

CONCLUSIONS: These prospective data from 2 generations of the Framingham Heart Study provide evidence that individuals with higher serum uric acid; including younger adults, are at a higher future risk of type 2 diabetes independent of other known risk factors. These data expand on cross-sectional associations between hyperuricemia and the metabolic syndrome, and extend the link to the future risk of type 2 diabetes.