Ten-year change in serum uric acid and its relation to changes in other metabolic risk factors in young black and white adults: the CARDIA study

Elevated serum uric acid is commonly seen in association with obesity, glucose intolerance, hypertension and dyslipidemia. There is currently no satisfactory explanation for the relation of uric acid and the metabolic syndrome (MetSyn). This study aimed to evaluate the relations of change in serum uric acid with changes in components of the MetSyn in young adults. We studied 1,249 male and 1,362 female black and white subjects aged 17-35 years (baseline) from the Coronary Artery Risk Development in Young Adults (CARDIA) Study, which attended a 10-year follow-up. Metabolic factors assessed at both time periods included BMI, waist circumference, blood pressure, fasting glucose, insulin, and lipids. Confounders examined (baseline and change variables) were serum creatinine, alcohol, smoking, physical activity, and oral contraceptives. Mean uric acid increased the most in black males (+0.5 mg/dl), followed by white males (+0.3 mg/dl) and black females (+0.2 mg/dl) (all P < 0.01), with the least change among white females (+0.1 mg/dl) (ns). Although change in all of the metabolic factors was associated with change in uric acid in the anticipated directions, in multivariable analyses only BMI and triglycerides had a significant independent association with uric acid in all race-sex-groups. Among confounders, only change in serum creatinine showed a strong independent association with uric acid. In conclusion, besides weight gain and renal excretion, increasing uric acid concentrations in young adults are strongly related to corresponding changes in triglycerides. The correlation of uric acid and triglycerides was found within the normal range and could not be explained by obesity.