New blood pressure guidelines released

The American Heart Association, along with the American College of Cardiology and nine other associations, released the 2017 Hypertension Clinical Practice Guidelines on Monday, Nov. 13, during Scientific Sessions 2017. This marks the first time the guidelines have been updated since 2003 and the first reclassification of blood pressure since 1993.

The key takeaways from these guidelines focus on how blood pressure is evaluated and measured. The 2017 standards are now defined as:

  • Normal: Less than 120 systolic mm HG; less than 80 diastolic mm HG
  • Elevated: Systolic between 120-129 mm Hg; diastolic less than 80 mm Hg
  • Stage 1 Hypertension: Systolic between 130-139 mm HG; diastolic between 80-89 mm HG
  • Stage 2 Hypertension: Systolic at least 140 mm Hg or diastolic at least 90 Hg
  • Hypertensive crisis: Systolic over 180 mm Hg and/or diastolic over 120 mmHg

Previously, high blood pressure was defined as readings greater than 140 for the systolic measurement and greater than 90 for the diastolic measurement.

“It’s a new system,” says Paul Whelton, MB, MD, MSc, lead author of the guidelines, which were published in the American Heart Association journal Hypertension and in the Journal of the American College of Cardiology.

“It will take a while to get used to it, but I think it’s the right system. It will capture those at risk better than our former system,” he says, in the AHA video “Understanding the 2017 Hypertension Guidelines.”

The category of prehypertension has been eliminated. Individuals who were previously classified with prehypertension will now be categorized as having either elevated blood pressure or Stage 1 hypertension. Individuals previously diagnosed with hypertension will now fall into the Stage 2 hypertension category.

Why the change in nomenclature? “We didn’t like the previous term (prehypertension) because it suggests that you’re still OK. You’re ‘pre’ hypertension. You don’t have it yet,” explains Whelton. “It’s clear from the information that’s available now that you’re not normal. You’re in that Stage 1 category at about twice the risk for a heart attack as somebody with a normal blood pressure. That’s why we changed it.”

The change in categories is expected to triple the number of men under 45 who have high blood pressure and double the number of women under 45. However, this change isn’t expected to lead to a large increase in the number of individuals prescribed blood pressure medications. Instead, individuals affected at the lower end of the scale will be encouraged to make lifestyle changes to lower their numbers.

The guidelines introduce new methods to evaluate blood pressure. An individual’s blood pressure measurement needs to be based on an average of two or three readings on at least two different occasions. Individuals are strongly encouraged to take their own blood pressure at home using a validated device. This monitoring can reveal “masked hypertension,” where blood pressure registers as normal in a clinical setting but higher at home.

The guidelines will work best with an implemented team approach between clinicians and patients. According to Whelton, “The patient is really important in all aspects of diagnosis, understanding the true exposure of the body to blood pressure and, then of course, in the therapy of those who have high blood pressure.”

Other guideline changes include:

  • Only prescribing medication for Stage 1 hypertension if a patient has already had a cardiovascular event or is at risk of heart attack or stroke based on age or the presence of certain diseases
  • As many individuals will need multiple medications to manage their blood pressure, medications will need to be combined into a single pill so as to encourage individuals to take the pill consistently
  • Identifying socioeconomic status and psychosocial stress as risk factors for high blood pressure

The 2017 Hypertension Clinical Practice Guidelines are based on a study involving 21 multidisciplinary groups that evaluated more than 900 studies. Click here to watch the complete video of Whelton discussing the guidelines with John Warner, MD, president of the American Heart Association. The complete guidelines manuscript is available online, as well.