Serum uric acid independently predicts mortality in patients with significant, angiographically defined coronary disease

Background: Uric acid is a nontraditional risk factor implicated in the development of coronary artery disease (CAD). This study prospectively evaluated the predictive value of serum uric acid (SUA) levels for mortality after angiographic diagnosis of CAD.

Methods: Blood samples were collected from 1,595 consecutive, consenting patients with significant, angiographically defined CAD (stenosis 70%). Baseline and procedural variables were recorded and levels of SUA were measured. Patients were followed to death or to the time of contact (mean 2.6 years, range 1.8-5.0 years).

Results: Patients averaged 65 +/- 11 years of age, 78% were male and 170 subjects died during the follow-up period. In univariate analysis of prospectively defined quintiles, SUA predicted all-cause mortality (fifth quintile vs. first four quintiles: hazard ratio 1.9, p < 0.001). In multivariable Cox regression controlling for 20 covariables, independent predictive value for mortality was retained by SUA (hazard ratio 1.5, confidence interval 1.02-2.1, p = 0.04). In subgroup analysis based on diuretic use status, SUA independently predicted mortality among patients not using diuretics, while SUA was not a significant predictor of mortality among those who used diuretics.

Conclusions: In patients with significant, angiographically defined CAD, SUA predicted mortality independent of traditional risk factors. This suggests that elevated SUA may be a risk factor for mortality in patients with significant cardiovascular disease and may be a stronger secondary than primary risk factor in CAD.