Combination of ankle brachial index and diabetes mellitus to predict cardiovascular events and mortality after an acute coronary syndrome

Objective: Diabetes mellitus and low ankle brachial index (ABI) are both conditions associated with an increased cardiovascular risk. In the setting of an acute coronary syndrome (ACS), diabetes is associated with increased mortality, but little is known regarding a low ABI. The aim of the study was to evaluate the prevalence of diabetes and low ABI in patients after an ACS and their prognostic value.

Methods: 1156 patients ≥40 years admitted with an ACS were screened with ABI previous to hospital discharge to investigate the presence of peripheral arterial disease (PAD) (ABI value≤0.9). 1054 were finally followed for one year. Patients were stratified according to diabetes and PAD status. The primary endpoint of the study was all-cause mortality.

Results: The prevalence of diabetes was 36% and PAD was 39.9%. After a median follow up of 382 days, 59 patients died (5.6%), the majority from a cardiovascular event. In both diabetic and nondiabetic patients, the presence of PAD was significantly associated with an increased incidence of the primary event. After adjustment for several prognostic variables, patients with diabetes and PAD had an increased risk of mortality (HR 4.05 (95% CI 1.86-8.83)). PAD and diabetic patients had an intermediate and similar incidence of cardiovascular events.

Conclusions: Our results show that the presence of an ABI≤0.9 predicts cardiovascular risk to the same extent as diabetes, and the combination of diabetes and PAD is a powerful tool after an ACS to predict the occurrence of an adverse event.