More than 85 percent of African-American men and women are likely to develop hypertension in their lifetimes based on the new cutoff for high blood pressure established in the 2017 U.S. guidelines, researchers reported March 27 in JAMA Cardiology.
A substantially higher proportion of white and black men and women will have an office measurement above the 130/80 mm Hg threshold between the ages of 20 and 85, the analysis found, compared to the previous definition of 140/90 mm Hg set forth in the Seventh Joint National Commission (JNC7) guidelines. But the racial gap in hypertension prevalence also narrows among men with the new definition, suggesting more white men fall within the 130/80 to 140/90 range than black men.
“Quantitation of the cumulative lifetime risks for hypertension may help public health officials identify groups at high risk for hypertension who may benefit from more aggressive lifestyle modification, screening, and medical therapy to prevent associated illnesses later in life,” wrote lead author Vincent Chen and colleagues with Northwestern University Feinberg School of Medicine. “Existing estimates of lifetime risks for hypertension are based on JNC7 thresholds, are limited in racial diversity, or do not provide risk estimates over the entire adult life course.”
To update these estimates with the newer cutoffs, the researchers pooled data from three contemporary U.S. cohorts including large numbers of black and white participants who were enrolled at a median age of 25. The final analysis set featured 13,160 participants who were followed for a total of 227,600 person-years.
After adjusting for baseline hypertension prevalence and competing risks of death, the researchers estimated the lifetime risk of hypertension—defined as a single blood pressure measurement of 130/80 or higher or the initiation of antihypertensive medication—was:
- 83.8 percent in white men
- 86.1 percent in black men
- 69.3 percent in white women
- 85.7 percent in black women
Under the JNC7 definition for high blood pressure, lifetime risks for the same study cohort were 60.5 percent in white men, 74.7 percent for black men, 53.9 percent for white women and 77.3 percent for black women.
“The attenuation of difference in lifetime risk between African American and white men (with the more recent guidelines) should not be misinterpreted to indicate an attenuation of disparities in hypertension-associated illness,” the researchers cautioned, “because African American men may have higher mean blood pressure levels, poorer blood pressure control when receiving pharmacotherapy, and other unmeasured factors that may drive documented differences in incident stroke, coronary heart disease, chronic kidney disease, and heart failure across racial/ethnic groups.”
With the newly lowered bar for hypertension, Chen et al. estimated 30.7 percent of white men and 23.1 percent of black men in their 20s would have high blood pressure. The prevalence of hypertension at that age was much lower in women—12.3 percent in blacks and 10.2 percent in whites.
“The high prevalence of hypertension at ages 20 to 30 years underscores the importance of hypertension awareness and primordial prevention targeting children, adolescents, and young adults,” the authors wrote.
Chen and co-authors acknowledged their approach of using one measurement classify a participant as hypertensive may have resulted in an overestimation of the disease. The 2017 guidelines require an elevated BP on two or more clinical encounters to confirm hypertension.