People with blood pressure at the high end of what used to be considered normal - now termed “Prehypertension” - run an increased risk of developing cardiovascular disease and having a Heart Attack, a new study indicates.

Hypertension is defined as blood pressure greater than 140/90 - the readings when the heart contracts and when it relaxes between beats. Prehypertension has been newly defined as blood pressure in the range 120-139/80-89.

“The evidence suggests that prehypertension is not a benign category but in fact has a greater risk of Heart Attack associated with it,” said Dr. Adnan I. Qureshi from the University of Medicine and Dentistry of New Jersey in Newark.

He said the finding “raises the question of whether these patients should be treated with antihypertensive medication to reduce their risk of Heart Attacks.” That would amount to treating 60 million more people in United States with blood pressure-lowering drugs.

Qureshi and his colleagues used data from 5181 participants in the Framingham Heart Study to examine the association between prehypertension, hypertension and the incidence of Stroke, Heart Attack and coronary artery disease.

They report in the American Heart Association’s journal Stroke that individuals with prehypertension were 3.5 times more likely to have a Heart Attack and 1.7 times more likely to develop heart disease than people with lower blood pressure.

Not surprisingly, people with prehypertension were also more likely to develop full-blown hypertension compared with those with normal blood pressure.

Prehypertension did not appear to significantly raise the risk of Stroke. “This is somewhat surprising, but it may be related to the small number of stroke events in the study,” Qureshi said in a statement.

“Prehypertension ... represents a unique category of pressure,” the researcher commented. “These persons do not meet the criteria for high pressure but they do not have normal pressure either. As it stands today, we routinely do not treat these patients with antihypertensive medication.”

Qureshi’s team says further studies are needed to “confirm the anticipated benefits of identifying and intervening in persons with prehypertension.”

SOURCE: Stroke, August 2005.