Estimating the risk of peripheral artery disease using different population strategies

The objective of this study is to compare the clinical performance of different strategies, REASON, PREVALENT, Inter-Society Consensus (ISC), and the American College of Cardiology/American Heart Association (ACC/AHA) Guidelines, in the selection of candidates for peripheral artery disease (PAD) screening using ankle-brachial index (ABI).

Our work is a population-based cross-sectional study conducted in Extremadura (Spain) in 2007-2009. Participants were ≥50years old and free of cardiovascular disease. ABI and cardiovascular risk factors were measured.

In total, 1288 individuals (53% women), with a mean age of 63years (standard deviation (SD) 9) were included. The prevalence of ABI <0.9 was 4.9%. REASON risk score identified 53% of the sample to screen with sensitivity of 87.3%, quite similar to that identified in ISC and ACC/AHA strategies (both 90.5%), and specificity of 48.3%, higher than that of the ISC (30.9%) and ACC/AHA (31.1%) strategies. Although the Youden index was 0.4 for both REASON and PREVALENT risk scores, the latter's sensitivity was 60.3%, almost 30 points less than all other strategies.

REASON risk score was the strategy with the highest clinical performance and efficiency, with sensitivity of 87.3% and specificity higher than that of the ISC and ACC/AHA strategies. Although very specific, the PREVALENT strategy had low sensitivity making it difficult to be implemented as a screening tool.