Meta-Analyses of Statin Therapy for Primary Prevention Do Not Answer Key Questions: An Empirical Appraisal of 5 Years of Statin Meta-Analyses

Although meta-analyses of statins in primary prevention are designed to provide doctors and patients with better evidence about the risks and potential benefits of treatment, they may ignore important patient-centered outcomes and concerns. We examined all meta-analyses of statins for primary prevention over the last 5 years. We assessed whether each meta-analysis addressed five key points: whether authors examined endpoints based on the use of statin therapy, and not stratified by low-density lipoprotein reduction; whether authors included only studies of statin versus placebo, and not varying doses or brands of statin; whether authors considered commonly cited harms; whether secondary prevention patients were excluded; and, whether overall mortality was examined. We examined 189 articles to identify 24 meta-analyses of statins that made claims regarding primary prevention. Six studies (25 %) reported outcomes as a function of reduction in serum lipid levels rather than treatment received. Seven studies (29 %) included trials of high-dose versus low-dose statin in their analysis. Five studies (21 %) did not examine all-cause mortality. The majority of studies (n = 21, 88 %) failed to exclude patients with known cardiovascular disease, and 22 (92 %) studies failed to assess two of three common safety concerns. Nevertheless, most (n = 20, 83 %) meta-analyses supported the use of statins in primary prevention. Based on our findings, we conclude that most recent meta-analyses of statins for primary prevention do not adequately address the question they seek to answer.