In this issue of JFP, MacLaughlin and colleagues echo the recommendations of the 2017 American College of Cardiology/American Heart Association (ACC/AHA) guidelines on high blood pressure (BP).1
This guideline, however, is not endorsed by primary care organizations. Both the American College of Physicians (ACP) and the American Academy of Family Physicians (AAFP) released their own evidence-based guideline in 2017.2 (The European Society of Cardiology also declined to endorse the ACC/AHA guideline.3) So how do we make sense of the different recommendations? And how do we decide which guideline is most trustworthy?4
Evidence based vs evidence informed
Both guideline writing groups are highly respected and affiliated with influential organizations. Both claim their guidelines are based on scientific evidence and are crafted with the intention to improve health. The 2 guidelines, however, differ in their fidelity to the evidence-based process and in their willingness to generalize disease-centered interventions to non-diseased populations.
Evidence-based guidelines differ from evidence-informed guidelines. Evidence-based guidelines have an established methodology that includes well-designed specific critical questions, a literature review with clearly defined inclusion and exclusion criteria, an evidence grading system, and a systematic approach to creating recommendations. Evidence-based guidelines are limited in scope and are often controversial because the evidence may not comport with the narrative promulgated by experts. Indeed, the controversy surrounding the 2014 Eighth Joint National Committee (JNC 8) guideline that I co-chaired focused on the one recommendation with the strongest evidence.5,6
Comprehensive guidelines written by experts are by their very nature evidence-informed guidelines. The ACC/AHA guidelines are comprehensive, providing a panoply of recommendations. When such guidelines are written for primary care, the generalizability of specialized disease-centered knowledge is limited,7 and the risk of overdiagnosis and overtreatment rises,8 especially when the primary care community is not invited as equal partners in the guideline development process.
Trustworthy guidelines require management of conflicts of interests. A hidden contributor to guideline panel membership and content is organizational sponsorship. Advocacy organizations and specialty societies have governing boards that have fiduciary responsibilities to their organizations. Such responsibilities may supersede the responsibilities of guideline panel members and influence content. JNC 8’s appointed panel members chose to release the 2014 guideline independently, so as not to cede editorial authority to governing boards of associations with potential conflicts of interest.
As Paul Frame said, “An ounce of prevention is a ton of work.”9
Dr. Frame, a family medicine pioneer who applied evidence-based medicine to preventive practice, encouraged us to ask critical questions that must be supported by scientific evidence before implementing these practices in healthy populations.10 The ACC/AHA guidelines advocate recommendations based on untested assumptions: that improved health results from earlier “diagnosis” and disease labeling of individuals with risks (healthy patients), and that such patients should receive aggressive “prevention” with daily and lifelong medications requiring physician monitoring.11 To support their new diagnostic standards, the authors cite similar relative risk (RR) reductions (an outcome-based measure), while discounting the smaller absolute risk (AR) reductions (a population-based measure) in studies supporting lower BP goals.
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