Hypertension clinical practice guidelines are inconsistent among different professional organizations, making medical decision-making difficult. The Joint National Committee (JNC) defines stage 1 hypertension as a systolic blood pressure of 140-149 or a diastolic blood pressure of 90-99. However, in 2017, the American College of Cardiology (ACC) and the American Heart Association (AHA) released new Hypertension Clinical Practice Guidelines, which redefined stage 1 hypertension as a systolic blood pressure of 130-139 or a diastolic blood pressure of 80-89. This change was largely based on the controversial 2015 SPRINT trial in which three blood pressures were taken five minutes apart in a room without any medical professionals after a patient had five minutes of quiet rest. This method of blood pressure measurements is entirely unrealistic in a typical outpatient clinic and has been demonstrated to be up to 10/5 mm Hg lower than if measured with standard office-based protocols.
Much to the chagrin of the ACC/AHA, these lower blood pressure targets have not been universally adopted and were not endorsed by the American College of Physicians (ACP) and American Academy of Family Physicians (AAFP). In response, the ACC/AHA Task Force on Performance Measures set out to revise the 2011 performance measures to better align with the new ACC/AHA clinical guidelines rather than the JNC guidelines. The 2019 ACC/AHA Clinical Performance and Quality Measures contains 22 new quality measures to assess the ability of the American healthcare system to diagnose and treat hypertension in accordance with the new ACC/AHA classification of stage I hypertension. The measures include six process quality measures, 10 structural quality measures, and six performance measures specifically designed for use by national programs such as the Centers for Medicare and Medicaid Services (CMS).
As many organizations including CMS have not adopted the new ACC/AHA 130/80 stage 1 hypertension targets, the writing committee created “harmonizing measures” which are aligned with the prior JNC 140/90 target blood pressure. However, the other measures are termed “enhancing measures” and are meant to emphasize improved outcomes with the lower target blood pressure of 130/80. Out of the 12 performance and process quality measures, seven of these measures use the new ACC/AHA targets. In addition, one of the prior measures was completely retired as it was not in alignment with the 2017 Hypertension Clinical Practice Guidelines.
While the goal of the revised measures is to improve diagnosis and treatment of high blood pressure in the United States, these measures were developed with the new ACC/AHA stage I hypertension diagnosis in mind. The writing committee wants to push physicians away from the higher JNC target and towards the 2017 Hypertension Clinical Practice Guideline recommendations, and these performance measures reflect that. Keep in mind that if CMS were to adopt these performance measures, there would be potentially significant financial implications as many provider incentives are based on meeting these kinds of performance measures.
Driving blood pressure lower and lower is not without risk (read this EBM Focus article for a discussion of possible risks highlighted in previous studies). Concerns about the generalizability of the outcomes of the SPRINT trial are a big reason that the ACP and AAFP did not endorse the 2017 ACC/AHA guideline recommendations. However, these concerns extend to potentially overlooked clinical consequences for patients, including overtreatment, acute kidney failure, hypotension, and electrolyte abnormalities. On a broader scale, it’s important to remember that new doesn’t always mean better. When clinical practice guidelines differ, it is critical that healthcare professionals are able to understand the reasons behind the differences, or at least to know the clinical resources available to help guide them in clinical decision-making.
