Systolic blood pressure differences between the left and the right arm could be signs of vascular disease and increase the risk of dying, according to new research published online The study is a detailed review of 28 blood pressure studies. It found "significant evidence" that different readings on both arms are associated with increased risk of peripheral vascular disease (PVD), the narrowing of arteries that supply blood to the legs and feet, and cerebrovascular disease, which affects the blood supply to the brain.
More alarming is the finding that inconsistent blood pressure readings between the two arms increase the risk of a cardiovascular death by a whopping 70 per cent. The risk of death from any cause is increased by 60 per cent.
These risks were associated with a difference of 15 points or higher in blood pressure readings from each arm.
The authors of the study, led by Dr. Christopher E. Clark of the University of Exeter in the U.K., say measuring blood pressure on both arms should be the new standard in doctors' offices and hospitals.
"The message is important and it is telling you that the horse is getting out of the barn in terms of managing the risk of hypertension," he said.
It's the difference between the two measurements -- not which arm is higher or lower -- that counts, The Lancet study says.
Early detection of PVD is important because medications and lifestyle changes -- such as weight loss or smoking cessation -- can reduce its impact and the risk of death, the study's authors say.
They warn that most cases of PVD are "clinically silent." The disorder can be diagnosed by measuring the ratio of blood pressure in the patient's ankle and arm at rest or after a stress test.