This transcript has been edited for clarity.
I’m Dr. Neil Skolnik. There are very few things that we treat more often than hypertension, so you’d think the guidelines would have been clear a long time ago. Less than 10 years ago, in 2014, JNC 8 (Eighth Joint National Committee) recommended target blood pressure for individuals under 60 to be less than 140/90, and for those older than 60, less than 150/90.
Then, based primarily on the SPRINT trial (which included only people with or at significantly elevated risk for atherosclerotic cardiovascular disease), in 2017 the American Heart Association’s hypertension guidelines lowered the target BP to less than 130/80 for most individuals. It’s a little more nuanced than that, but most of us don’t remember the nuance. I’ve written about my reservations with that statement in the AHA’s journal, Circulation.
Now the American Academy of Family Physicians has updated its recommendations, and they recommend a BP less than 140/90. This is not a small change, as it often takes additional medication to achieve lower BP targets, and additional medicines lead to additional adverse effects. I’m going share with you some details from the new guideline, and then I’m going share my opinion about it.
The AAFP guideline applies to adults with hypertension, with or without cardiovascular disease. In the comprehensive literature review, the trials ran for an average of 3.7 years, and about 75% of the patients in the trials did not have preexisting cardiovascular disease.
The key to their recommendations is that target BPs lower than 140/90 did not show a statistically significant decrease in total mortality. In regard to serious adverse events, though, lower targets led to a nominal increase that didn’t reach statistical significance. Serious adverse events were defined as death or events that required hospitalization or resulted in significant disability. In regard to all other adverse events, including syncope and hypotension, there was a significant increase, with a relative risk of 1.44 (a 44% increase in adverse events). This reflected an absolute risk increase of 3%, compared with the standard target group (specifically 9.8% vs. 6.8%), with a number needed to harm of 33 over 3.7 years.
Another potential harm of low BP targets was the need for an average of one additional medicine to reach lower BP targets. One systematic review cited an eightfold higher withdrawal rate because of adverse events in the lower-target BP groups.
The AAFP guidelines said that, in the comprehensive review of the literature, while there was no difference in mortality or stroke with lower BP targets, a small additional benefit was observed in myocardial infarction – a 16% lower incidence, with a number needed to treat of 137 over 3.7 years.
So that’s the background. Let me now go over the specifics of the AAFP recommendations.
AAFP gives a strong recommendation for a standard BP target of less than 140/90. They go on to say – and grade this next statement as a weak recommendation – that, while treating to a lower BP target does not provide additional mortality benefit, a target BP of less than 135/85 can be considered to lower the risk for MI, noting that lower BP may increase harms. They state that the lower BP target could be considered based on patient preferences and values.
The AAFP guideline is incredibly helpful. The difference in the recommendations of two large societies – American Heart Association and AAFP — stems from two things. I believe that AHA focused on the composite endpoints in trials such as SPRINT, which included only high-risk patients, and the AAFP uses mortality as the driving endpoint in a broader group of patients that included both high- and lower-risk patients.
In addition, it appears that the two organizations weigh adverse events differently in coming to their conclusions. Clearly, we see more adverse events when aiming for a lower BP level, and in my experience, patients care a lot about adverse events.
Interestingly, the International Society of Hypertension recommends an “essential” BP target of less than 140/90 for most individuals, and for those under 65, they provide the option of an “optimal” BP of less than 130/80. Remember that for certain comorbidities there are also other guidelines out there. The American Diabetes Association this year revised its target BP to less than 130/80 for people with diabetes; for prevention of recurrent stroke, guidelines from the AHA/American Stroke Association in 2021 recommend BP less than 130/80, and the International Society for Hypertension as well as the AHA recommends a BP of less than 130/80 for those with established atherosclerotic cardiovascular disease.
To repeat, though, the main topic for today is that as a general target, the AAFP guidelines recommend a BP less than 140/90.
Dr. Skolnik is professor, department of family medicine, Sidney Kimmel Medical College, Philadelphia, and associate director, department of family medicine, Abington (Pa.) Jefferson Health. He disclosed conflicts of interest with AstraZeneca, Teva, Eli Lilly, Boehringer Ingelheim, Sanofi, Sanofi Pasteur, GlaxoSmithKline, Merck, and Bayer.
A version of this article first appeared on Medscape.com.
*This article was updated on 2/7/2023.