Predictors of contrast-induced acute kidney injury in patients with coronary artery disease receiving contrast agents twice within 30 days

BACKGROUND: None of study mentioned about contrast-induced acute kidney injury (CI-AKI) in people who have received contrast agents twice within in a short period of time. This study is trying to identify the predictors. METHODS: We enrolled 607 patients between Oct. 2010 and Jul. 2015 who received contrast agents twice within 30 days in the Department of Cardiology of the General Hospital of Shenyang Military Region. The primary outcome was CI-AKI within 72 h after contrast agent exposure. Patients were divided into groups A (n = 559) and group B (n = 48) according to whether CI-AKI occurred after the second agent. RESULTS: Patients in group B (CI-AKI occurred after the second agent) had a more rapid heart rate and more usage of diuretics and digitalis. In group B, CI-AKI occurred more frequently after the first agent. Multivariate logistic regression showed that diuretic (P = 0.006) and intra-aortic balloon pump (IABP) usage (P = 0.012) were independent predictors of CI-AKI after the first agent. Angiotensin-converting enzyme inhibitor/Angiotensin II receptor antagonist (ACEI/ARB) usage (P = 0.039), IABP usage (P = 0.040) and CI-AKI occurring after administration of the first agent (P = 0.015) were independent predictors of CI-AKI after the second. Furthermore, dividing the patients into tertiles of the time interval between the two agents showed that CI-AKI occurred more frequently when the second agent was administered within 1–3 days after the first exposure than within 4–6 days (12.4% vs. 5.0%, P = 0.008) or ≥ 7 days (12.4% vs. 6.4%, P = 0.039). CONCLUSIONS: Diuretic and IABP usage are independent predictors of CI-AKI following exposure to a first contrast agent. The major predictors of CI-AKI after exposure to a second agent are time since the first contrast exposure, ACEI/ARB usage, and IABP usage. More importantly, a three-day interval between the two agents is associated with a higher incidence of CI-AKI following the second administration.