Serum uric acid / serum creatinine ratio as a predictor of cardiovascular events. Detection of prognostic cardiovascular cut-off values
Edoardo Casiglia, Valérie Tikhonoff, Agostino Virdis, Guıdo Grassı, Fabio Angeli, Carlo M. Barbagallo, Michele Bombelli, Arrigo F.G. Cicero, Massimo Círillo, Pietro Cirillo, Raffaella Dell’Oro, Lanfranco D’Elia, Giovambattista Desideri, Claudio Ferri, Ferruccio Galletti, Loreto Gesualdo, Cristina Giannattasio, Guido Iaccarino, Luciano Lippa, Francesca Mallamaci, Stefano Masi, Alessandro Maloberti, Maria Masulli, Alberto Mazza, Alessandro Mengozzi, María Lorenza Muiesan, Pietro Nazzaro, Paolo Palatini, Gianfranco Parati, Roberto Pontremoli, Fosca Quarti‐Trevano, Marcello Rattazzi, Gianpaolo Reboldi, Giulia Rivasi, Massimo Salvetti, Giuliano Tocci, Andrea Ungar, Paolo Verdecchia, Francesca Viazzi, Massimo Volpe, Claudio Borghi
Abstract
OBJECTIVE: In the frame of the Uric Acid Right for Heart Health (URRAH) study, a nationwide multicenter study involving adult participants recruited on a regional community basis from all the territory of Italy under the patronage of the Working Group on Uric Acid and Cardiovascular Risk of the Italian Society of Hypertension, we searched for the cut-off values of the ratio between serum uric acid (SUA) and serum creatinine (sCr) able to predict cardiovascular (CV) events. METHODS: Among 20 724 participants followed-up for 126 ± 64 months, after detecting cut-off by the receiver operating characteristic curves, we calculated by Cox models adjusted for confounders having CV events as dependent variable the hazard ratio (HR) of SUA/sCr > cut-off. We also verified if the role of cut-off varied with increasing SUA/sCr. RESULTS: A plausible prognostic cut-off of SUA/sCr was found and was the same in the whole database, in men and in women (>5.35). The HR of SUA/sCr > cut-off was 1.159 (95% confidence interval [CI] 1.092-1.131, P < 0.03) in all, 1.161 (95% CI 1.021-1.335, P < 0.02) in men, and 1.444 (95% CI 1.012-1.113, P < 0.03) in women. In increasing quintiles of SUA/sCr the cut-offs were >3.08, >4.87, >5.35, >6.22 and >7.58, respectively. The HRs significantly increased from the 3rd to the 5th quintile (1.21, 95% CI 1.032-1.467, P = 0.018; 1.294, 95% CI 1.101-1.521, P = 0.002; and 1.642, 95% CI 1.405-1.919, P < 0.0001; respectively), that is, over 5.35, whereas the 2nd quintile was not significantly different from the 1st (reference). CONCLUSION: Having SUA/sCr >5.35 is an independent CV risk indicator both in men and women. The cut-off is dynamic and significantly increases with increasing SUA/sCr.