Ankle brachial index identifies CVD risk earlier

THE high prevalence of peripheral arterial disease (PAD) in primary care patients should prompt more frequent and earlier use of ankle brachial index (ABI) in the assessment of cardiovascular risk, experts say.

The comments follow a European study that found as many as one in five of 6880 men and women aged 65 years or older had PAD, with more than half of these being asymptomatic.

The authors said measurement of ABI provided prognostic information for asymptomatic PAD that could not be derived from conventional risk factors alone.

“This early form of PAD has been underestimated, under-diagnosed and under-treated because of a mistaken belief it is relatively benign,” they said.

“But high mortality and vascular event rates show the risk these patients face and the importance of treating the condition early.”

Professor Richard Harper, emeritus director of cardiology at Monash Medical Centre, said ABI had probably been underused, given it attracted a Medicare rebate and added additional information to standard risk factors.

“ABI could be a useful screening test [to detect atherosclerosis] in men over 50 with one or more cardiovascular risk factors or strong family history, and women with two or more,” he said.

“The Heart Foundation needs to look at it because it’s simple, cheap and more suitable as a screening test than angiography or calcium scores as part of a prevention strategy,” he said.

The Heart Foundation’s national manager of clinical programs, Dr Nancy Huang, said: “ABI shows promise as being a cheap, simple way to diagnose atherosclerosis, but... more trials are needed to see if adding ABI improves management.”

Circulation, online 9 November