Stroke risk is lower for healthy older adults with blood pressure under 140 mm Hg than in the disputed 140 to 149 mm Hg range, particularly for minorities and women, according to a cohort study.
In the prospective population-based Northern Manhattan Study cohort of 1,750 people 60 and older, and free of stroke, diabetes, and chronic kidney disease (CKD) at baseline, the adjusted odds of incident stroke over a median 13 years of annual follow-up were a significant 70% higher with a systolic blood pressure of 140 to 149 mm Hg than with lower blood pressures.
The association was only seen among Hispanics and non-Hispanic blacks, with odds ratios of 2.61 and 1.93, respectively, Ralph L. Sacco, MD, of the University of Miami, and colleagues reported online ahead of print in the March issue of Hypertension.
Likewise, the higher stroke risk in the 140 to 149 mm Hg range was significant for women (adjusted hazard ratio 1.98, 95% CI 1.22-3.24) but not for men (aHR 1.33, 95% CI 0.65-2.72).
The Northern Manhattan Study analysis started soon after an unofficial 2014 report from members of the disbanded Eighth Joint National Committee panel made the controversial recommendation to relax the treatment threshold from 140 to 150 mm Hg for people 60 and older who don't have diabetes or CKD, Sacco noted in a press release.
The findings suggested that such a shift "could have a detrimental effect on stroke risk and may contribute to stroke disparities across race-ethnicity and sex," Sacco's group concluded in the paper.
"In general, our findings support adherence to the current American Heart Association guidelines that consistently recommend treatment for blood pressure above 140/90 mmHg in order to improve cardiovascular health and reduce stroke," Sacco said in the release.
Prior analyses have also predicted that loosening the blood pressure cuff to 150 mm Hg systolic could have a big public health cost in cardiovascular events. Although the SPRINT trial showed mortality and overall cardiovascular risk reduction with an even lower target, under 120 mm Hg, for selected older or high-risk adults, the impact on stroke was not significant, Sacco's group noted.
However, following SPRINT and recent supporting meta-analyses, "it is now timely to rethink blood pressure thresholds and targets," Rhian M. Touyz, MD, PhD, and Anna F. Dominiczak, MD, both of the University of Glasgow, wrote in an editorial commentary released online ahead of the April issue of Hypertension.
"Exactly what the future recommendations will be remain uncertain because the data from the recent studies still need to be digested and further analyzed in the context of current evidence-based studies," they noted, "but it is very likely that there will be a strong move toward more aggressive control of hypertension to lower blood pressure targets.
"With the awaited new American College of Cardiology/American Heart Association guidelines soon to be finalized, reassessment of existing guidelines and more SPRINT substudies to be published, the landscape of diagnosing and treating hypertension may change significantly in the near future."