Combined Lipid Lowering by Ezetimibe and Statin and Coronary Plaque Regression: A Meta- Analysis of Randomized Controlled Trials
Background: It is not clear whether the addition of ezetimibe to statin will result in greater reduction in coronary plaque. We aimed to perform a meta-analysis of all RCTs and prospective studies that evaluated role of dual lipid lowering strategy in atherosclerosis regression. Methods: We searched PubMed, EMBASE, Cochrane CENTRAL, Scopus and relevant references for RCTs (inception through December 20, 2015 without language restrictions) and performed meta-analysis using random effects model. Percentage change in plaque volume, change in lumen volume, percentage change in LDL, HDL and hsCRP were measured outcomes. Results: 3 RCTs and 1 prospective non randomized trial with a total population of 554 comprising mostly of Asian population were analyzed. Statin plus ezetimibe showed significantly greater lowering of plaque volume than statin alone (WMD -4.13 mm3 range of -7.42 mm3 to 0.85 mm3; p=0.01); there was a trend towards increased lumen volume in combination group without statistical significance [WMD 1.90 mm3 (-4.61 to 8.40); p=0.57).Combination strategy resulted in significantly higher percentage lowering of LDL at the end of follow up [WMD: -16.16(-22.47 to -9.85) p ≤ 0.00001]. No differences in percentage change in HDL and hsCRP were observed between two groups. Conclusion: Combination lipid lowering by statin plus ezetimibe causes significantly greater reduction in plaque volume and lowering of LDL cholesterol. Further larger studies are needed to validate the findings in all population groups.