Editor's Choice – Cohort Study Examining the Association Between Abdominal Aortic Size and Major Adverse Cardiovascular Events in Patients with Aortic and Peripheral Occlusive and Aneurysmal Disease

Abstract

The aim of this study was to examine whether there were independent associations between abdominal aortic diameter, size index, and height index and the risk of major adverse events in patients referred for treatment of various types of aortic and peripheral occlusive and aneurysmal disease (APOAD). In total, 1 752 participants with a variety of APOADs were prospectively recruited between 2002 and 2020 and had a maximum abdominal aortic diameter, aortic size index (aortic diameter relative to body surface area), and aortic height index (aortic diameter relative to height) measured by ultrasound at recruitment. Participants were followed for a median of 4.6 years (interquartile range 2.0 - 8.0 years) to record outcome events, including major adverse cardiovascular events (MACE), peripheral artery surgery, abdominal aortic aneurysm (AAA) events (rupture or repair), and all cause mortality. The association between aortic size and events was assessed using Cox proportional hazard analysis. The ability of aortic size to improve risk of events classification was assessed using the net reclassification index (NRI). After adjusting for other risk factors, larger aortic diameter was associated with an increased risk of MACE (hazard ratio [HR] 1.17, 95% confidence interval [CI] 1.05 - 1.31), requirement for peripheral artery surgery (HR 2.05, 95% CI 1.90 - 2.22), AAA events (HR 3.01, 95% CI 2.77 - 3.26), and all cause mortality (HR 1.20, 95% CI 1.08 - 1.32). Findings were similar for aortic size and aortic height indices. According to the NRI, all three aortic size measures significantly improved classification of risk of peripheral artery surgery and AAA events but not MACE. Aortic size index, but not aortic diameter or aortic height index, significantly improved the classification of all cause mortality risk. Larger abdominal aortic diameter, size index, and height index are all independently associated with an increased risk of major adverse events in patients with established vascular disease.