Blood Pressure Often Differs Widely Between Two Arms: Study

blood pressure checkBlood pressure readings between the two arms can be different, and that disparity can sometimes be a warning sign of heart trouble down the road.

That’s the finding of an analysis of 24 past studies: When people have at least a 5-point difference in blood pressure between the two arms, their risk of heart attack, stroke or premature death inches up. And the greater the difference, the more those risks climb.

Experts said the findings give more support to something that’s been advocated, but not commonly done by doctors and nurses: Checking patients’ blood pressure in both arms.

“Unfortunately, blood pressure is not routinely measured in both arms,” said Dr. Jeffrey Berger, a cardiologist who was not involved in the study. “But I think it should be.”

Berger directs the Center for the Prevention of Cardiovascular Disease at NYU Langone Health in New York City. He said he always checks blood pressure in both arms, and thinks it should be a matter of routine in all patients.

“It’s such a simple thing to do,” Berger said.

It’s not that the blood pressure difference, itself, is the problem. But a discrepancy between arms might be a sign of early atherosclerosis that is developing asymmetrically, Berger explained.

Atherosclerosis refers to a hardening and narrowing in the arteries that, eventually, could lead to heart disease or stroke.

Measuring blood pressure in both arms gives doctors “a simple way of noticing possible arterial stiffening,” said Dr. Christopher Clark, lead researcher on the new analysis.

There’s no way to “fix” between-arm discrepancies, but that’s not the point, said Clark, a clinical senior lecturer at the University of Exeter Medical School in the United Kingdom.

Instead, he explained, doctors can consider between-arm differences one “marker” of a patient’s heart disease risk.

And then what? Berger said it depends on a patient’s overall health. Eating more healthfully and getting regular exercise is always wise, he said, but some people might need medication, like a statin, to ward off cardiovascular trouble.