Communicating Statin Evidence to Support Shared Decision-Making

Bruce Barrett; Jason Ricco; Margaret Wallace; David Kiefer; Dave Rakel


BMC Fam Pract. 2016;17(41) 

In This Article


The practice of medicine rests on foundations of knowledge accumulated over centuries, from simple observation to large and rigorous randomized controlled trials (RCTs). Following the principles of evidence-based medicine, systematic reviews of RCTs allow for authoritative interpretation of best available evidence. And yet, even with well-proven medical interventions, there are potential harms as well as benefits, which may be valued quite differently by individual patients. This, combined with varying levels of understanding among clinicians and patients, yields substantive complexity and uncertainty at the individual decision-making level. This paper uses the example of statins for preventing cardiovascular events (heart attacks and strokes, primarily), to discuss the principles and practice of evidence-informed shared decision-making, emphasizing the importance of individual values, and the effective communication of probabilities.

Cardiovascular (CV) disease, causing heart attack, stroke and other CV events, is the leading cause of death and disability in the developed world.[1,2] Of the conventional risk factors, age, sex, and family history (genetic predisposition) are fixed, but blood pressure, cholesterol, blood sugar, tobacco use, stress, depression, diet, and exercise are all considered targets in the effort to reduce the impact of heart attack, stroke, and other patient-oriented CV outcomes.

For people with the CV risks of dyslipidemia, hypertension and diabetes, numerous pharmaceutical interventions are available. For people with moderate to severe hypertension, several classes of drugs appear to be effective in reducing stroke and heart attack risk.[3,4] For mild hypertension, evidence of pharmaceutical effectiveness is less clear.[5,6] Drugs aimed at diabetes can improve glycemic control, and may improve some microvascular outcomes, but have marginal effects on CV outcomes.[7,8] While several types of cholesterol-targeting drugs have been shown to modify the lipid profile in favorable directions, only statins (HMG co-A reductase inhibitors) have been shown to reduce CV event rates.[2,9–11]

In the past several years, there has been a minor increase in evidence available regarding statins for preventing CV events, and a major change in the translation of evidence into guidelines.[12–14] The recent 2013 American Heart Association and American College of Cardiology (AHA/ACC) guidelines endorse statin treatment when 10 year CV event risk is as low as 7.5 %,[15] and the 2014 U.K. National Institute for Health and Care Excellence (NICE) guidelines suggest that clinicians "Offer atorvastatin 20 mg for the primary prevention of CVD to people who have a 10 % or greater 10-year risk of developing CVD".[2] Only a few years earlier, guidelines from the same organizations supported statins only for people with 20 % or higher 10 year CVD event risk.[16,17]

This article focusses on statins for preventing CV events, but the principles of evidence-informed shared decision-making apply widely. See Table 1. The aims of this article are to:

  1. Summarize current evidence regarding statins for preventing CV events

  2. Identify limitations of the most recent guidelines

  3. Outline an evidence-informed approach towards shared decision making

  4. Use two case examples to illustrate this approach

  5. Suggest a few potentially fruitful future directions for the development and use of clinical guidelines and decision aids