Structured Abstract
Background:
Cardiovascular disease (CVD) is the leading cause of mortality and morbidity in the United States but is potentially preventable with statin therapy. The U.S. Preventive Services (USPSTF) commissioned this review to inform the development of new recommendations on use of statin therapy for prevention of CVD in adults.
Purpose:
To evaluate benefits and harms of statin therapy for prevention of CVD in adults without prior cardiovascular events.
Data Sources:
We searched the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and MEDLINE to June 2016 and manually reviewed reference lists.
Study Selection:
Randomized, controlled trials on the benefits and harms of statin therapy versus placebo or no statin in adults without prior cardiovascular events.
Data Extraction:
One investigator abstracted data and a second investigator checked data abstraction for accuracy. Two investigators independently assessed study quality using methods developed by the USPSTF.
Data Synthesis (Results):
Nineteen trials with followup from 6 months to 6 years compared statin therapy versus placebo or no statin. Statin therapy was associated with decreased risk of all-cause mortality (risk ratio [RR], 0.86 [95% CI, 0.80 to 0.93]; absolute risk difference [ARD], -0.40%; number needed to treat [NNT], 250), cardiovascular mortality (RR, 0.82 [95% CI, 0.71 to 0.94]; ARD, -0.20%; NNT, 500), stroke (RR, 0.71 [95% CI, 0.62 to 0.82]; ARD, -0.38%; NNT, 263), myocardial infarction (RR, 0.64 [95% CI, 0.57 to 0.71]; ARD, -0.81%; NNT, 123), and composite cardiovascular outcomes (RR, 0.70 [95% CI, 0.63 to 0.78]; ARD, -1.39%; NNT, 72). Relative benefits appeared to be consistent in subgroups defined by demographic and clinical characteristics, including populations with cardiovascular risk factors without marked hyperlipidemia. Statin therapy was not associated with significantly increased risk of serious adverse events (RR, 0.99 [95% CI, 0.94 to 1.04]), myalgia (RR, 0.96 [95% CI, 0.79 to 1.16]), or liver-related harms (RR, 1.10 [95% CI, 0.90 to 1.35]). Statins were not associated with increased risk of diabetes (RR, 1.05 [95% CI, 0.91 to 1.20]), though statistical heterogeneity was present (I2=52%), and one trial found that high-intensity statins were associated with increased risk (RR, 1.25 [95% CI, 1.05 to 1.49]). No trial directly compared titrated versus fixed-dose statin therapy. Based on an analysis of individual patient data from randomized trials, greater reductions in low-density lipoprotein cholesterol levels with statin therapy are associated with reduced risk of CVD events, which may provide some indirect evidence that higher-intensity therapy may be associated with better clinical outcomes than lower-intensity therapy.
Limitations:
Restricted to English language, statistical heterogeneity in some pooled analyses, and limited formal assessment for publication bias.
Conclusions:
In adults at increased CVD risk but without prior CVD events, statin therapy is associated with reduced risk of all-cause and cardiovascular mortality and CVD events. Benefits appear to be present across diverse demographic and clinical subgroups, with greater absolute benefits in patients at higher baseline risk, and do not appear to be restricted to patients with marked hyperlipidemia.
Contents
- Acknowledgements
- 1. Introduction
- 2. Methods
- 3. Results
- Key Question 1a. What Are the Benefits of Treatment With Statins in Reducing the Incidence of CHD- or CVA-Related Morbidity or Mortality or All-Cause Mortality in Asymptomatic Adults Age 40 Years or Older Without Prior CVD Events?
- Key Question 1b. What Are the Benefits of Treatment With Statins That Target LDL-C Versus Other Treatment Strategies in Adults Age 40 Years or Older Without Prior CVD Events?
- Key Question 1c. Do the Benefits of Treatment With Statins in Adults Age 40 Years or Older Without Prior CVD Events Vary in Subgroups Defined by Demographic or Clinical Characteristics?
- Key Question 2. What Are the Harms of Statins in Adults Age 40 Years or Older Without Prior CVD Events?
- Key Question 3. How Do Benefits and Harms Vary According to Potency of Statin Treatment?
- Contextual Question 1. What Is the Comparative Accuracy of Different Cardiovascular Risk Assessment Methods?
- Contextual Question 2. How Do Lipid Levels Change Over Time in Adults Age 40 Years or Older?
- 4. Discussion
- References
- Appendix A. Detailed Methods
- Appendix B. Abbreviations of Trial Names
- Appendix C. Evidence and Quality Tables
- Appendix D. Meta-Analysis Figures
Suggested citation:
Chou R, Dana T, Blazina I, Daeges M, Bougatsos C, Grusing S, Jeanne TL. Statin Use for the Prevention of Cardiovascular Disease in Adults: A Systematic Review for the U.S. Preventive Services Task Force. Evidence Synthesis No. 139. AHRQ Publication No. 14-05206-EF-2. Rockville, MD: Agency for Healthcare Research and Quality; 2016.
This report is based on research conducted by the Pacific Northwest Evidence-based Practice Center (EPC) under contract to the Agency for Healthcare Research and Quality (AHRQ), Rockville, MD (Contract No. HHSA-290-2012-00015-I, Task Order No. 2). The findings and conclusions in this document are those of the authors, who are responsible for its contents, and do not necessarily represent the views of AHRQ. Therefore, no statement in this report should be construed as an official position of AHRQ or of the U.S. Department of Health and Human Services.
The information in this report is intended to help health care decisionmakers—patients and clinicians, health system leaders, and policymakers, among others—make well-informed decisions and thereby improve the quality of health care services. This report is not intended to be a substitute for the application of clinical judgment. Anyone who makes decisions concerning the provision of clinical care should consider this report in the same way as any medical reference and in conjunction with all other pertinent information (i.e., in the context of available resources and circumstances presented by individual patients).
This report may be used, in whole or in part, as the basis for development of clinical practice guidelines and other quality enhancement tools, or as a basis for reimbursement and coverage policies. AHRQ or U.S. Department of Health and Human Services endorsement of such derivative products may not be stated or implied.
None of the investigators have any affiliations or financial involvement that conflicts with the material presented in this report.
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5600 Fishers Lane, Rockville, MD 20857; www
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Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239; www
.ohsu.edu/epc