Relation between high Ankle-Brachial Index and cardiovascular outcomes in the general population and cardiovascular disease: a meta-analysis.

INTRODUCTION

Conflicting findings have been reported on the association between high Ankle-Brachial Index (ABI) and cardiovascular outcomes. This meta-analysis aimed to assess the association of abnormally high ABI and cardiovascular outcomes in the general population and suspected or established cardiovascular disease (CVD) patients.

EVIDENCE ACQUISITION: A comprehensive literature search was conducted in PubMed and Embase databases through November 10th, 2018. All observational studies evaluating the association of high ABI with cardiovascular events including stroke, coronary heart disease (CHD), congestive heart failure, and composite of CVD/all-cause mortality in the general population and suspected or established CVD patients were included. We pooled risk ratios (RR) with 95% confidence intervals (CI) for the abnormally high ABI (> 1.3 or >1.4) versus the reference normal ABI category.

EVIDENCE SYNTHESIS: We identified 10 cohort studies enrolling 39,421 participants. A random effect model meta-analysis indicated that the pooled RR of composite of CVD/all-cause mortality was 1.07 (95% CI 0.83-1.38) in the general population and 1.26 (95% CI 1.03-1.55) in suspected or established CVD patients. Moreover, participants with abnormally high ABI did not increase the risk of stroke (RR 1.60; 95% CI 0.83-3.06) and CHD (RR 1.40; 95% CI 0.87-2.24) in the general population.

CONCLUSIONS

Abnormally high ABI appears to be associated with an increased risk of a composite of CVD/all-cause mortality in suspected or established CVD patients but not in the general population. However, additional well-designed studies are required to support the current findings.