Relations of hyperuricemia with the various components of the insulin resistance syndrome in young black and white adults: The CARDIA study

PURPOSE: To assess the association of hyperuricemia with the various components of the Insulin Resistance Syndrome (IRS) in a biracial cohort of young adults. METHODS: Cross-sectional study in 4053 young black and white adults aged 18-30 years from the Coronary Artery Risk Development in Young Adults (CARDIA) study. RESULTS: Body mass index (BMI), fasting insulin, and triglycerides were significantly higher, and high density lipoprotein (HDL)- cholesterol lower in subjects with hyperuricemia (uric acid ≤ 7.0 mg/dl in males; ≤ 6.0 mg/dl in females) (all p < 0.001). BMI showed the strongest positive correlation with uric acid among the IRS components. Significant associations of hyperuricemia with these risk factors were observed in all sex-race groups, which persisted after controlling for possible confounders including age, education, physical activity, smoking, alcohol intake, oral contraceptive use, and creatinine. Further adjustment for BMI and/or waist- to-hip ratio caused a large decrease in the strength of the associations. Adjustment for insulin also lead to decreases; however, the influence of fasting insulin appeared weaker than obesity. Even after controlling for obesity, insulin, and the other components of the IRS, male subjects in both races in the upper tertile of triglycerides were still more likely to have hyperuricemia. CONCLUSIONS: The association of hyperuricemia with most aspects of the IRS may result predominantly from their covariation with adiposity and secondarily with insulin level. Elevated triglyceride level seems to have an independent relationship with hyperuricemia in males. The relationship between hyperuricemia and cardiovascular disease observed in previous studies may be secondary to its association with the IRS.