Relation of Uric Acid Levels to Presence of Coronary Artery Calcium Detected by Electron Beam Tomography in Men Free of Symptomatic Myocardial Ischemia With Versus Without the Metabolic Syndrome

The objective of this study was to evaluate whether uric acid (UA) levels were associated with coronary artery calcium (CAC) in white men asymptomatic for coronary heart disease. We also evaluated whether this relation was dependent or not on the presence of the metabolic syndrome (MS). The study population consisted of 371 asymptomatic Brazilian men (48 ± 7 years of age) who underwent a routine evaluation. The average 10-year total risk of coronary heart disease calculated by Framingham risk score was 10.8 ± 7.8%. The age-adjusted prevalence of CAC in patients with a high UA level (fourth quartile ≥7.1 mg/dl, n = 91) was significantly higher than that in those with a normal UA level (58% vs 44%, p = 0.02). With respect to age, smoking, physical activity, and components of MS-adjusted analyses, a high UA level was independently associated with the presence of CAC (p = 0.043) and with increasing levels of CAC (p = 0.028). Prevalence of MS showed a graded increase according to serum UA values. In patients with the MS, after adjusting for age, smoking, physical activity, and white blood cell count, high levels of UA were strongly associated with the presence of any CAC (odds ratio 3.47, 95% confidence interval 1.26 to 9.53, p = 0.01) and with increasing levels of CAC (odds ratio 2.74, 95% confidence interval 1.15 to 6.50, p = 0.02). Conversely, there was no significant association of high UA levels in patients without the MS. However, the interaction between high UA level and the MS did not achieve statistical significance for the presence of CAC (p = 0.11) or higher levels of CAC (p = 0.16). In conclusion, our study suggests that, among asymptomatic moderate-risk men, high UA levels were independently associated with CAC in subjects with the MS.