ABSTRACT: BACKGROUND: There have been conflicting results across the trials that evaluated prophylactic efficacy of short-term high-dose statin pre-treatment for prevention of contrast-induced acute kidney injury (CIAKI) in patients undergoing coronary angiography (CAG). The aim of the study was to perform an up-to-date meta-analysis regarding the efficacy of high-dose statin pre-treatment in preventing CIAKI. METHODS AND RESULTS: Randomized-controlled trials comparing high-dose statin versus low-dose statin or placebo pre-treatment for prevention of CIAKI in patients undergoing CAG were included. The primary endpoint was the incidence of CIAKI within 2-5 days after CAG. The relative risk (RR) with 95% CI was the effect measure. This analysis included 13 RCTs with 5,825 total patients; about half of them (n = 2,889) were pre-treated with high-dose statin (at least 40 mg of atorvastatin) before CAG, and the remainders (n = 2,936) pretreated with low-dose statin or placebo. In random-effects model, high-dose statin pre-treatment significantly reduced the incidence of CIAKI (RR 0.45, 95% CI 0.35-0.57, p<0.001, I(2)= 8.2%, NNT 16), compared with low-dose statin or placebo. The benefit of high-dose statin was consistent in both comparisons with low-dose statin (RR 0.47, 95% CI 0.34-0.65, p<0.001, I(2) = 28.4%, NNT 19) or placebo (RR 0.34, 95% CI 0.21-0.58, p<0.001, I(2)= 0.0%, NNT 16). In addition, high-dose statin showed significant reduction of CIAKI across various subgroups of chronic kidney disease, acute coronary syndrome, and old age (? 60 years), regardless of osmolality of contrast or administration of N-acetylcystein. CONCLUSIONS: High-dose statin pre-treatment significantly reduced overall incidence of CIAKI in patients undergoing CAG, and emerges as an effective prophylactic measure to prevent CIAKI.