(HealthDay)—Ankle-brachial index (ABI) detected by an alternative method involving the lower of two systolic ankle pressures (LABI) is more sensitive and better for predicting peripheral artery disease (PAD), according to a study published in the Oct. 1 issue of The American Journal of Cardiology.

Vinodh Jeevanantham, M.D., from the University of Kansas Medical Center in Kansas City, and colleagues assessed the utility and difference between two ABI techniques for predicting PAD. ABI was assessed using the conventional method, derived as the ratio of the two systolic ankle blood pressures to the higher brachial pressure (HABI method), and using the LABI method. One hundred thirty patients (260 limbs) who underwent both ABI measurements were enrolled.

The researchers found that ABI was <0.9 (abnormal) in 68 and 84 percent of patients by HABI and LABI methods, respectively. Compared with the HABI method, the LABI method had higher sensitivity and overall accuracy to detect PAD. Compared with HABI, LABI-detected abnormal ABI was more likely to predict angiographic PAD and total PAD burden. Compared with the HABI method, LABI-detected abnormal ABI had higher sensitivity and accuracy for detecting PAD in patients with diabetes and below knee PAD.

"In conclusion, ABI determined by the LABI method has higher sensitivity and is a better predictor of PAD compared with the conventional (HABI) method," the authors write.