Blood pressure should be measured in both arms, says study

PTI

BloodPressure, BP

London, 02 Feb 2012: Doctors should measure blood pressure in both arms as routine, as a difference between the left and the right arm could indicate an increased risk of vascular disease and death, a new study has claimed.

 

Existing guidelines state that blood pressure should be measured in both arms, but it is not often done. The findings mean that measurement of blood pressure in both arms should be part of routine care, the researchers said.

 

For their study, published in The Lancet, a team led by Dr Christopher Clark at the Peninsula College of Medicine and Dentistry at University of Exeter in the UK reviewed 28 study papers and found that a difference of 15mm of mercury or more in systolic blood pressure (SBP) between the arms is linked to hardening of the arteries supplying blood to legs and feet.

 

“Our findings suggest that a difference in SBP of 10 mm Hg or more or 15 mm Hg or more between arms could identify patients at high risk of asymptomatic peripheral vascular disease and mortality who might benefit from further assessment, said the authors.

 

Dr Clark and his team found that a difference in systolic blood pressure of 10 millimetres of mercury (mm Hg) between arms could identify patients at high risk of asymptomatic peripheral vascular disease.

 

A difference of 15mg Hg would also indicate an increased risk of cerebrovascular disease, a 70 per cent increased risk of cardiovascular mortality and 60 per cent increased risk of death from all causes, the authors said.

 

Peripheral vascular disease (PVD) is the narrowing and hardening of the arteries that supply blood to the legs and feet. There are often no symptoms. Early detection of PVD is important because interventions to promote smoking cessation, lower blood pressure, or offer statin therapy can reduce mortality, the authors noted.

 

However, the researchers pointed out that most of the cases are clinically silent, and gold-standard non-invasive identification of this disease requires detection of a reduced ankle-brachial pressure index (ratio of BP in ankle to BP in arm) at rest or after a stress test.

 

This complex technique requires time, experience, and training; it is not routinely undertaken in primary-care assessment of hypertensive patients and is not proposed within the UK vascular check programme.

 

Thus, the findings of this new study further support the need for both-arm blood pressure checks to be the norm, said Dr Clark. However, other experts said more research is needed to clarify whether substantial differences between arms should prompt aggressive management of cardiovascular risk factors.

 

“Overall, Clark and colleagues’ systematic review and meta-analysis supports existing guidelines stating that blood pressure should be measured in both arms. Ascertainment of differences should become part of routine care, as opposed to a guideline recommendation that is mostly ignored,” said Prof Richard J McManus of University of Oxford and Prof Jonathan Mant of University of Cambridge.