Alternative ankle–brachial assessments show no significant added value in predicting mortality of hypertensive patients

Abstract

Background: Peripheral artery disease (PAD), assessed via the ankle–brachial index (ABI), is a recognised form of hypertension-mediated organ damage (HMOD). While alternative ABI calculations have shown improved sensitivity for PAD detection, their prognostic utility in hypertensive populations remains unclear. Methods: In this prospective cohort study of 21875 hypertensive individuals (ERV Study), we compared the prognostic performance of three ABI-based approaches: standard ABI using the higher ankle pressure (ABI-HIGH), ABI using the lower ankle pressure (ABI-LOW), and multivessel ABI scoring (number of vessels with ABI 0.90). The primary endpoint was all-cause mortality, assessed over a median follow-up of 5 years using interval-censored Cox regression. Results: PAD prevalence was 14.4% using ABI-HIGH and 28.3% using ABI-LOW, with 13.9% of patients identified only by the latter. All PAD definitions were independently associated with mortality. ABI, as a continuous variable, demonstrated the strongest association (hazard ratio, 1.87; 95% CI, 1.63–2.16). Multivessel ABI showed a dose–response relationship with mortality. However, overall discrimination was modest: time-dependent AUCs ranged from 0.608 to 0.635 for ABI-based models alone. When added to clinical predictors, BMI metrics improved the AUC to a range from 0.763 to 0.780, with the AUC to arange from 0.763 to 0.780,with added value between 6 and 11%. Conclusion: In hypertensive individuals, ABI-LOW and multivessel scoring identify more PAD cases and are independently associated with mortality. However, their incremental value in mortality risk prediction is limited. Alternative ABI methods may assist in identifying higher-risk subgroups warranting further vascular assessment.