Stroke: New Evidence on Blood Pressure Limits

Countering the argument that hypertension is being overtreated, a University of Miami-Columbia University study found that changing the definition of high blood pressure would be a bad idea.

The debate arose after a report published in the Journal of the American Medical Association in 2014 advised doctors to aim for blood pressure readings of less than 150/90 mm HG for patients 60 or older without other illnesses. That raised the standard for “healthy” systolic blood pressure by 10 points from the previous guidance, and sparked controversy.

The research looked at the incidence of stroke in 1,706 people over age 60 who did not have a history of stroke, chronic kidney disease, or diabetes.

They found that stroke risk was 70 % higher for patients with a reading of 140 to 149 mm Hg than it was for patients with readings under 140 mm Hg. That increased risk was nearly equal to that faced by patients with readings of 150 mm Hg.

The study was done by Chuanhui Dong, PhD, at University of Miami and was reported by Ralph Sacco, MD, MS at the American Heart Association/American Stroke Association International Stroke Conference in Nashville, Tenn.

The study group, taken from Columbia University Medical Center’s catchment area in northern Manhattan, was racially and ethnically diverse—including populations that are prone to high blood pressure, Sacco said, particularly Hispanics (63%). The team found that 13 years into the research, the study group’s members had 176 strokes.

In tracking the relationship of blood pressure to stroke occurrence, he said, “The relative risk (1.7) for people with numbers of 140 to 149 was just as high as for those with 150.”

To say that patients with blood pressure in that range do not need to take medications and other steps to lower their blood “could be deleterious,” Sacco said.