An assessment of a screening method for peripheral arterial disease of the lower limbs in patients aged at least 65 years at the Yaoundé Central Hospital, Cameroon

Abstract

The automatic measurement of the Ankle-Brachial Index (ABI) constitutes a reliable, simple, safe, rapid, and inexpensive alternative diagnostic screening test compared with the Doppler method for peripheral arterial disease (PAD). We aimed to compare the diagnostic performance of automatic ABI measurement tests to Doppler ultrasound for PAD in patients aged ≥ 65. This was an experimental comparative study of Doppler ultrasound's performance to the automated ABI test in diagnosing PAD in patients aged ≥ 65 years followed up at the Yaoundé Central Hospital, Cameroon, between January to June 2018. An ABI threshold < 0.90 defined a PAD. We compare the sensitivity, and specificity of the high Ankle-Brachial Index (ABI-HIGH), low Ankle-Brachial Index (ABI-LOW), and the mean Ankle-Brachial Index (ABI-MEAN) for both tests. We included 137 subjects with an average age of 71.7 ± 6.8 years. In the ABI-HIGH mode, the automatic device had a sensitivity of 55% and a specificity of 98.35% with a difference between the two techniques of d = 0.024 ( P = 0.016). In the ABI-MEAN mode, it had a sensitivity of 40.63% and a specificity of 99.15%; d = 0.071 ( P < 0.0001). In the ABI-LOW mode, it had a sensitivity of 30.95% and a specificity of 99.11%; d = 0.119 ( P < 0.0001). Compared to the Doppler method, the ABI-HIGH mode of the automatic measuring device had better diagnostic performance and can thus be used as a screening test for PAD patients aged ≥ 65 years in our context.