Lower BP Targets Can Save Over 300,000 Lives a Year, Analysis Suggests

Tighter blood pressure control has the potential to save hundreds of thousands of lives and prevent more than half a million CVD events each year among adults in the United States, new data suggest.

In an interview with TCTMD, the study’s senior author said the findings underline the importance of following the stricter treatment recommendations from the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) hypertension guideline, and should be considered sufficient to persuade those not yet convinced that lower is better.

“Those numbers clearly show that reducing blood pressure to a lower level will substantially further reduce cardiovascular disease and mortality in the population,” said Jiang He, MD, PhD, (Tulane University School of Public Health and Tropical Medicine, New Orleans, LA). “I hope our data will be able to convince healthcare providers to follow the new guidelines.”

Benefits Outweigh Risks

In a paper published online May 23, 2018, ahead of print in JAMA Cardiology, He and colleagues, led by Joshua D. Bundy, PhD, MPH (Tulane University School of Public Health and Tropical Medicine), report the results of an analysis of the impact of treating patients according to the 2017 ACC/AHA hypertension guideline recommendation of < 130/80 mmHg rather than the 2014 evidence-based guideline from the Eighth Joint National Committee (JNC 8) recommendation of < 140/90 mmHg. Using data from the National Health and Nutrition Examination Surveys (NHANES) from 2013 and 2016, they created models to estimate how achieving the treatment goals of each guideline would affect morbidity and mortality in the US population.

Consistent with what has been previously suggested, the analysis confirmed that 45.4% of all adults over age 20 (105 million people) would be considered hypertensive, up from 32.0% (74 million people) under the JNC 8 guideline. The group most likely to be affected by this shift are middle-age men ages 40 to 59.

The percentage under the new guideline who would be considered eligible for pharmacologic therapy would increase from 31.1% to 35.9%, which represents 11 million additional people. The analysis suggests that these increases would be similar across racial and ethnic groups. Individuals age 60 and over would account for most of the increase in candidates for antihypertensive therapy, roughly 6.6 million, but the analysis suggests they would also be the group that would reap the greatest benefit in terms of reduction in CVD events and mortality under the new guideline.

Assuming 100% compliance with the 2017 guideline, there would be approximately 610,000 fewer nonfatal strokes, MIs, and CV deaths annually compared with 270,000 fewer events under the old guideline. Moreover, there would be 334,000 fewer total deaths vs 177,000 fewer under the old guideline. Given the low likelihood of 100% compliance, however, the researchers also calculated the impact of lower levels of compliance. With 50% achievement of the 2017 guideline, there would be approximately 305,000 fewer CVD events and 167,000 fewer deaths. In comparison, achieving 75% of the JNC 8 guideline would reduce CVD events by only 203,000 and deaths by 133,000.

Additionally, the number needed to treat (NNT) to prevent one CVD event was lower under the 2017 guideline than under the JNC 8 recommendations (70 vs 88). Similarly, the NNT to prevent one death was lower under the new guideline (129 vs 134).

The analysis also looked at the impact of the new guideline versus the old one on adverse events, finding that tighter BP control would likely contribute to 62,000 additional diagnoses of hypotension, 32,000 cases of syncope, 31,000 cases of electrolyte abnormalities, and 79,000 cases of acute kidney injury or failure.

To TCTMD, He said the magnitude of the health and survival benefits of lowering BP to the new goal, as demonstrated in the analysis, should far outweigh potential concerns among clinicians and patients regarding adverse events.

“If you look at the guidelines, they do recommend some individualized treatment strategies,” He said. “I still believe though, that even in the older population, less than 130 [mm Hg] is a reasonable goal.”

Treating the Untreated Should Take Priority

Acknowledging the contentious debate that has swirled around the newer guideline, Lawrence J. Fine, MD, DrPh (National Institutes of Health, Bethesda, MD), and colleagues write in an accompanying editorial that while the estimated benefits are based on multiple assumptions, “the major message is that the more complete achievement of either guideline treatment goal substantially reduces CVD events in the United States.”

Additionally, they say a recent estimate that 30,000 excess stroke deaths may have occurred in the US from 2013 to 2015 due to a slowing or stopping of the decline in stroke mortality “underlines the need to continue to make national progress in achieving better BP control rates.”

Fine and colleagues also say as important as it is to improve BP control for patients already on antihypertensive medications, identifying and treating those who are not on medication should be a high priority.

“For the 2014 and 2017 guidelines, nearly 17 and 28 million adults, respectively, are untreated,” they write. “Regardless of the guideline one prefers, we can agree that improved detection, treatment, and control are national and global priorities.”

Clyde W. Yancy, MD, MSc (Northwestern University, Chicago, IL) and Gregg C. Fonarow, MD (Ronald Reagan UCLA Medical Center, Los Angeles, CA), take this one step further, saying in an Editor’s Note that the morbidity and mortality benefits demonstrated by the new analysis amount to “an actionable clinical directive.” They add that “the benefit of hypertension therapy per the 2017 hypertension guidelines meets the bar to qualify as a robust prevention strategy.”

Yancy and Fonarow conclude that barriers to implementation of tighter BP targets should fall, and that “the time is on us to implement.”