should blood pressure be the same in both arms

Differences in blood pressure readings taken from the left and right arms may be a sign of heart and blood vessel disease and death risk, according to a new review of recent research.

Researchers found that a difference of 15 points or more in the readings between the left and right arms raised the risk of peripheral vascular disease, a narrowing or blockage of the arteries, by two-and-a-half times.

That same 15 point-difference in systolic readings (the top number in a blood pressure reading) also increased the risk of cerebrovascular disease by 60%. Cerebrovascular disease is associated with thinking problems, such as dementia, and an increased risk of stroke.

Researchers say the results suggest that doctors should routinely compare blood pressure readings from both arms to prevent unnecessary deaths.

Although the practice of taking blood pressure from both arms as a part of heart disease screening has been adopted in Europe, and some guidelines in the U.S. recommend it, American Heart Association spokesman Richard Stein, MD, says it’s not routinely done in the U.S.

“This is very interesting,” says Stein, professor of cardiology at the New York University School of Medicine. “It can translate immediately, as we learn more about it, into better detection of people at higher risk of disease.”

In the study, British researchers examined 20 studies covering differences in systolic blood pressure – the pressure of blood in arteries when the heart is contracting – between arms.

The results, published in The Lancet, showed that a difference of 15 points or more in the systolic readings between the left and right arms was associated with an increased likelihood of several heart-related risks,

The risk of peripheral vascular disease was two-and-a-half times higher.
The risk of cerebrovascular disease was 60% higher.
The risk of dying from heart and circulatory diseases rose by 70%.

The risk of peripheral vascular disease was also higher when there was a difference in blood pressure readings of 10 points or more.

If peripheral vascular disease is detected at an early stage, treatments such as stopping smoking, lowering blood pressure, or offering statin medication can reduce death rates.