89 Incremental benefits and harms of the 2017 american college of cardiology/american heart association high blood pressure guideline

Abstract

Objectives The recent recommendations from the American College of Cardiology and the American Heart Association (ACC/AHA) to lower the thresholds for defining hypertension follows a general pattern across medical specialties, whereby disease definitions are more frequently widened than narrowed. Such widened definitions usually label people as unwell, even if they are at low risk of a disease, and thus have the potential to cause harm. We aimed to assess the incremental benefits and harms of the definition used by the ACC/AHA guideline as compared to that used by the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7) using the checklist. Method We compared the previous and new definitions for Hypertension using a newly developed 8-item checklist: What are the differences between the previous and the new definition? How will the new disease definition change the incidence and prevalence of the disease? What is the trigger for considering the modification of the disease definition? How well does the new definition of disease predict clinically important outcomes compared with the previous definition? What is the repeatability, reproducibility, and accuracy of the new disease definition? Benefit: What is the incremental benefit for patients? Harm: What is the incremental harm for patients? What is the net benefit and harm for patients? Results For the majority of adults newly classified as having high blood pressure under the ACC/AHA guideline (80% of those newly diagnosed who have 20% 10 year risk or history of CVD – 2.8 million Americans), the incremental benefits may often outweigh the incremental harms, leading to net benefit. For some people with high risk, (such as the elderly, diabetics, and people with renal disease), and for the 11% of newly diagnosed who have 10%–20% 10 year risk (3.4 million Americans), the benefits and harms may often be in rough balance. Conclusions The 2017 ACC/AHA guideline would classify 31 million additional people in the United States as having hypertension. For the majority of these people, who are at low risk and not recommended for drug treatment, physicians should not label them as having hypertension. Physicians should continue to support healthy choices with regard to diet and physical activity regardless of whether the patient’s systolic blood pressure is above or below 130 mmHg. When there is a question of starting blood pressure medication, the risk of cardiovascular disease should be estimated using a reliable risk calculator and the potential benefits and harms discussed with the patient. Some people are willing to accept a moderate increase risk of a cardiovascular event to avoid taking daily medications, increased doses or more medications, and others are not in this situation, informed and shared decision-making is essential.