Diagnostic and prognostic value of uric acid in patients with acute dyspnea

Uric acid was shown to predict outcome in patients with stable chronic heart failure. Its impact in patients admitted in the Emergency Department with acute dyspnea, however, remains unknown.

We prospectively investigated the diagnostic and prognostic value of uric acid in 743 unselected patients presenting to the Emergency Department with acute dyspnea.

Uric acid at admission was higher in patients with acute decompensated heart failure (51% of the cohort) as compared with patients with noncardiac causes of dyspnea (median, 447 micromol/L vs 340 micromol/L, P <.001). The area under the receiver operating characteristic curve for the accuracy to detect acute decompensated heart failure was inferior for uric acid (0.70) than for B-type natriuretic peptide (area under the receiver operating characteristic curve 0.91, P <.001). Patients in the highest uric acid tertile more often required admission to the hospital (92% vs 74% in the first tertile, P <.001) and had higher in-hospital mortality (13% vs 4% in the first tertile, P <.001). Cumulative 24-month mortality rates were 28% in the first, 31% in the second, and 50% in the third tertile (P <.001). After adjustment in multivariable Cox proportional hazard analysis, uric acid predicted 24-month mortality independently of B-type natriuretic peptide (P=.003).

Our study first shows that uric acid, measured at Emergency Department admission or hospital discharge, is a powerful predictor of long-term outcome in dyspneic patients.