AAFP to Review AHA/ACC Redefinition of High Blood Pressure

Academy Continues to Endorse JNC8 Hypertension Guideline

November 15, 2017 02:02 pm Chris Crawford

The American Heart Association (AHA), along with the American College of Cardiology (ACC) and nine other health professional organizations, unveiled a new hypertension guideline Nov. 13 during the AHA's Scientific Sessions 2017 in Anaheim, Calif.  

[Young black woman using a home blood pressure monitor]

The AAFP was not involved in the development of the newly released guideline, and, at this time, the Academy continues to endorse the "2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8)."(jamanetwork.com)

The AAFP's Commission on Health of the Public and Science will formally review the AHA/ACC hypertension guideline and subsequently provide any related guidance to members.

Overview of the AHA/ACC Guideline

Published online in the AHA's Hypertension journal, the new guideline(hyper.ahajournals.org) covers detection, prevention, management and treatment of high blood pressure (HBP). Specifically, it calls for HBP to be treated with lifestyle changes and with medication as needed beginning at 130/80 mmHg rather than the previous commonly accepted threshold of 140/90 mmHg.

According to the AHA, the new threshold will lead to 46 percent of the U.S. adult population being categorized as having hypertension. Using the previous threshold, that figure was 32 percent of American adults.  

Story highlights
  • The American Heart Association (AHA) and the American College of Cardiology unveiled a new hypertension guideline Nov. 13 at the AHA's Scientific Sessions 2017 in Anaheim, Calif.
  • Published online in the AHA's Hypertension journal, the new guideline calls for high blood pressure (HBP) to be treated with lifestyle changes and with medication as needed starting at 130/80 mmHg rather than the previous commonly accepted threshold of 140/90 mmHg.
  • The AAFP currently endorses the "2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8)."

The authors said they anticipate the new guideline will primarily affect younger adults -- with the prevalence of HBP expected to triple among men younger than 45 and to double among women younger than 45. Even so, they noted that there should only be a small increase in the number of U.S. adults who will require antihypertensive medication.

Family Physician's Perspective

According to Jennifer Frost, M.D., medical director for the AAFP Health of the Public and Science Division, current evidence doesn't support an absolute threshold for initiating treatment, whether 130/80 mmHg or 140/90 mmHg, because there's a continuum of risk.

"The greatest benefit comes from treatment of very high blood pressures and for those with high cardiovascular risk," she told AAFP News. "As blood pressures get lower, the benefit of treatment gets smaller. This guideline moves the threshold down the continuum, which may benefit some individuals, but may also lead to unnecessary treatment and associated harms."

Frost said family physicians should approach hypertension treatment on an individualized basis, taking into account patients' histories, risk factors, preferences and resources.

"Whether or not to intensify blood pressure treatment should be based on an informed discussion with patients, with a consideration of potential benefits and harms," she noted.

Additional Guideline Details

According to an AHA news release,(newsroom.heart.org) the AHA/ACC guideline was written by a panel of 21 scientists and health experts who reviewed more than 900 published studies.

The new guideline outlines the following blood pressure categories:

  • Normal: Less than 120/80 mmHg
  • Elevated: Systolic BP (SBP) between 120-129 mmHg and diastolic BP (DBP) less than 80 mmHg
  • Stage 1 hypertension: SBP between 130-139 mmHg or DBP between 80-89 mmHg
  • Stage 2 hypertension: SBP at least 140 mmHg or DBP at least 90 mmHg
  • Hypertensive crisis: SBP greater than 180 mmHg and/or DBP greater than 120 mmHg, with patients needing prompt changes in medication if there are no other indications of problems, or immediate hospitalization if there are signs of organ damage.

The guideline eliminates the category of prehypertension, which previously referred to an SBP between 120-139 mmHg or a DBP between 80-89 mmHg.

Other changes include

  • prescribing medication for Stage 1 hypertension only if a patient has already had a cardiovascular event such as a heart attack or stroke, or is at high risk of heart attack or stroke based on age, the presence of diabetes mellitus, chronic kidney disease or calculation of atherosclerotic risk;
  • recognizing that many patients will need two or more types of medications to control their blood pressure, and that people may take their pills more consistently if multiple medications are combined into a single pill; and
  • identifying socioeconomic status and psychosocial stress as risk factors for HBP, which should be considered in a patient's plan of care.

Additionally, the guideline highlights the importance of home blood pressure monitoring using proper technique and validated devices. The authors recommend recording the average of two to three blood pressure readings at least two times a day to get an accurate measure and avoid the phenomena of white-coat hypertension and masked hypertension.

Frost agreed on that point, saying that taking blood pressure in the clinical setting isn't the best predictor of outcomes.

"Having measurements from different times of day, in different settings, gives a more complete and reliable picture of an individual’s blood pressure," she said.

AAFP Endorsement of 2014 JNC8 Guidelines

The authors of the new guideline contend it succeeds the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC7), issued in 2003 and overseen by the National Heart, Lung and Blood Institute (NHLBI).

It's worth noting that in 2013, the NHLBI asked the AHA and ACC to take over the management of guideline preparation for hypertension and other cardiovascular risk factors. However, a guideline panel that included family physician representation had already been appointed by NHLBI and was in the process of updating the JNC7 guideline.

Rather than turning the effort over to ACC/AHA, panel members opted to continue their work and released the JNC8 guidelines in February 2014 without the NHLBI's support. The AAFP endorsed the guidelines in July 2014.

Key recommendations from the JNC8 report include

  • in the general population 60 and older, initiate pharmacologic treatment to lower BP at an SBP of 150 mmHg or higher or a DBP of 90 mmHg or higher, and treat patients to a goal SBP lower than 150 mmHg and a goal DBP lower than 90 mmHg; and
  • in the general population younger than 60, initiate pharmacologic treatment at a DBP of 90 mmHg or higher or an SBP of 140 mmHg or higher and treat to goals below these respective thresholds.

Related AAFP News Coverage
Extended In-office BP Monitoring Could Reduce Hypertension Overtreatment
Family Physician Calls for New BP Monitoring Standards, Protocols

(3/22/2017)

Evidence-based Hypertension Guideline Garners AAFP Endorsement
(9/10/2014)

2014 Hypertension Guideline Stands to Simplify Treatment, Says Expert
AAFP to Begin Rigorous Process of Reviewing for Possible Endorsement

(12/18/2013)

AAFP Calls on NHLBI to Release Long-awaited Clinical Practice Guidelines
Changes to Guideline Development Process Spark Concern

(9/3/2013)

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Clinical Preventive Service Recommendation: Hypertension

Clinical Practice Guideline: Hypertension in Adults Over 60