Association of Ankle-Brachial Indices With Limb Revascularization or Amputation in Patients With Peripheral Artery Disease

Key Points Question Are ankle-brachial indices associated with limb outcomes in community-dwelling patients with peripheral artery disease as identified by computational approaches applied to electronic health records? Findings In this cohort study of 1413 community-dwelling patients, peripheral artery disease was identified and limb outcomes were retrieved by computational approaches applied to electronic health records. Ankle-brachial indices of 1.4 or greater were associated with limb amputation and ankle-brachial indices less than 0.5 were associated with limb revascularization. Meaning Severe disease and poorly compressible arteries detected by ankle-brachial indices were associated with adverse outcomes in community-dwelling patients with peripheral artery disease; ascertainment of peripheral artery disease phenotypes and outcomes by computational approaches applied to electronic health records is feasible.
Importance The prevalence and morbidity of peripheral artery disease (PAD) are high, with limb outcomes including revascularization and amputation. In community-dwelling patients with PAD, the role of noninvasive evaluation for risk assessment and rates of limb outcomes have not been established to date. Objective To evaluate whether ankle-brachial indices are associated with limb outcomes in community-dwelling patients with PAD. Design, Setting, and Participants A population-based, observational, test-based cohort study of patients was performed from January 1, 1998, to December 31, 2014. Data analysis was conducted from July 15 to December 15, 2017. Participants included a community-based cohort of 1413 patients with PAD from Olmsted County, Minnesota, identified by validated algorithms deployed to electronic health records. Automated algorithms identified limb outcomes used to build Cox proportional hazards regression models. Ankle-brachial indices and presence of poorly compressible arteries were electronically identified from digital data sets. Guideline-recommended management strategies within 6 months of diagnosis were also electronically retrieved, including therapy with statins, antiplatelet agents, angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers, and smoking abstention. Main Outcomes and Measures Ankle-brachial index (index ≤0.9 indicates PAD
This population-based cohort study evaluates whether ankle-brachial indices identified through electronic health records among community-dwelling patients with peripheral artery disease are associated with limb revascularization or amputation.