Effect of statin therapy on contrast-induced nephropathy after coronary angiography: a meta-analysis.

BACKGROUND Although the pleiotropic effects of statins are postulated to be renoprotective, clinical studies have demonstrated conflicting results. We undertook a meta-analysis of published trials to evaluate the impact of statin therapy on the incidence of contrast-induced nephropathy (CIN) in patients undergoing coronary angiography. METHODS We searched MEDLINE and EMBASE databases through December 2010 for articles evaluating the effect of statins on the incidence of CIN in patients undergoing coronary angiography. Odds ratios (OR) with 95% confidence intervals (CI) were calculated using random effects modeling. RESULTS Three randomized controlled trials involving 770 patients (330 in the statin group and 340 in the control group) and 7 non-randomized studies involving 31,959 patients (11,936 statin-pretreated and 20,023 statin-naïve). The definition of CIN varied somewhat among the studies. Based on the pooled estimate across the 3 randomized controlled trials, statin therapy did not significantly reduce the incidence of CIN compared to control (OR=0.76, 95% CI: 0.41-1.41, p=0.39). No significant heterogeneity was found in the randomized studies (I(2)=0%, p=0.48). The pooled analysis of the non-randomized studies showed a marginally significant benefit associated with statin therapy (OR=0.60, 95% CI: 0.36-1.00, p=0.05). There was significant heterogeneity among the non-randomized studies (I(2)=88%, p<0.00001). CONCLUSIONS Our meta-analysis suggests that statin therapy might be associated with a significant reduction in the incidence of CIN in patients undergoing coronary angiography. Further studies are warranted to clarify this issue.