A difference in blood pressure between the left and right arm could mean an increased risk of heart disease and death, a study led by a Devon GP has found.

The findings add support to calls for blood pressure to be checked on both arms as standard practice.

Researchers at the University of Exeter Peninsula College of Medicine and Dentistry (PCMD) reviewed 28 papers looking at variations in systolic blood pressure between the arms.

A high blood pressure reading is one that exceeds 140/90mm of mercury. The first figure is called the systolic pressure.

They discovered that a difference in systolic blood pressure of 10mm of mercury (mm HG) or more between the arms is linked to hardening of the arteries supplying blood to the legs and feet, known as peripheral vascular disease (PVD).

Early detection of PVD is important because these patients could then benefit from stopping smoking, lowering their blood pressure or being offered statin therapy.

Researchers also found that a difference of 15mm HG or more was associated with an increased risk of pre-existing cerebrovascular disease, which affects the blood supply to the brain and is often associated with cognitive diseases such as dementia.

And they said a difference of 15 mm HG was also linked with an increased risk of death – "both as a result of cardiovascular problems and generally".

Dr Christopher Clark, clinical academic fellow at PCMD and a GP at Witheridge Medical Centre in Tiverton, Mid Devon, led the research.

He said: "We know that we're supposed to check both arms, purely to make sure that there isn't a discrepancy for anyone whose diagnosis or treatment depends on an accurate blood pressure reading. This is advice that unfortunately isn't always followed through."

Dr Clark said he hoped this paper would encourage people to follow that advice, and added that where this new research extends medical knowledge is in showing a possible link between differences between the arms and vascular diseases.

He said: "We set out to investigate whether there was an association between differences in systolic blood pressure between arms and vascular disease and mortality.

"Our findings indicate a strong association, and that differences of 10mm Hg or 15mm Hg or more might help to identify patients who are at risk and who need further vascular assessment.

"More research is required in order to transfer our findings to clinical practice, but in the meanwhile we will be flagging the results of our review to the UK Vascular Check programme."

The UK Vascular Check Programme for over-40s which includes a test for hypertension, or high blood pressure, already advises that these measurements be taken in both arms.

But Dr Clark said surveys have shown that the average GP does not do this.

The authors of the paper said their findings further support the need for both-arm blood pressure checks to be the norm – not least because most cases are "clinically silent" and such checks would better identify those at risk. The review was published in The Lancet online yesterday.

The study is supported by the Royal College of General Practitioners, the South West GP Trust and the National Institute for Health Research Peninsula Collaboration for Leadership in Applied Health Research and Care.