Contrast Induced Nephropathy and 2-Year Outcomes of Iso-Osmolar Compared with Low-Osmolar Contrast Media after Elective Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES: This study investigated the relative incidence of contrast induced nephropathy (CIN) and long-term outcomes between iso-osmolar contrast media (IOCM) and low-osmolar contrast media (LOCM) undergoing elective percutaneous coronary intervention (PCI). METHODS: A total of 9,431 patients receiving elective PCI were enrolled in the cohort. The patients were divided into IOCM group and LOCM group. Propensity score matching (PSM) was applied to minimize the selection bias between groups. RESULTS: The multivariate analysis showed that the use of IOCM compared with LOCM did not affect the CIN incidence (odds ratio [OR], 0.912; 95% confidence interval [CI], 0.576–1.446; p=0.696). After PSM, the incidence of CIN was 1.5% and 4.0% in IOCM group (n=979) and LOCM group (n=979), respectively, p=0.001. IOCM significantly reduced the incidence of CIN compared with LOCM (OR, 0.393; 95% CI, 0.214–0.722; p=0.003). After 2 years of follow-up, the all-cause mortality was higher in IOCM group than LOCM group (2.1% vs. 0.9%, p<0.001). Cox regression analysis showed IOCM was not independent risk factor of 2-years all-cause mortality (OR, 0.849; 95% CI, 0.510–1.412; p=0.528). After PSM, the difference of all-cause death between groups disappeared (1.7% vs. 1.9%, p=0.739). Cox regression analysis showed that the use of IOCM compared with LOCM did not affect the incidence of 2-year all-cause mortality (OR, 1.037; 95% CI, 0.534–2.014; p=0.915). CONCLUSIONS: Compared with LOCM, IOCM significantly reduced the incidence of CIN after elective PCI, but had no significant effect on 2-year all-cause mortality.