Ankle-Brachial Index Changes in Patients with Diabetes Presenting with Acute Coronary Syndrome During the Early and Late Phases

Abstract

Background: The Ankle-Brachial Index (ABI) is a simple, noninvasive measure used to assess lower-extremity and systemic atherosclerosis. However, ABI is rarely used in patients with acute coronary syndrome (ACS), and current guidelines provide no specific recommendations for its use in this setting. Objectives: This study evaluated changes in ABI among patients with diabetes and ACS and compared the diagnostic performance of ABI between the acute and late phases of ACS. Methods: In this descriptive study, 100 patients with diabetes who were hospitalized for ACS were evaluated. Patient characteristics, including age, sex, vascular disease history, and smoking status, were extracted from medical records. The ABI was measured within the first 48 hours of hospitalization (acute phase) and reassessed 4 - 6 weeks later (late phase). Acute- and late-phase ABI values were compared to evaluate changes associated with peripheral arterial disease (PAD). Results: Among 100 patients with diabetes and ACS, 37% had an ABI < 0.9 during the acute phase, indicating PAD, compared with 34% during the late phase. Nine patients with severe PAD during the acute phase remained in the severe category during the late phase. One of the 18 patients with moderate PAD during the acute phase improved to mild PAD, and 3 patients with mild PAD during the acute phase had normal ABI values during the late phase. The sensitivity of acute-phase ABI for diagnosing PAD in patients with diabetes and ACS was 100%, and the specificity was 94%. Acute- and late-phase ABI values differed significantly, with higher values during the late phase. Conclusions: Acute-phase ABI lacks sufficient accuracy for diagnosing PAD in patients with diabetes and ACS, particularly in mild-to-moderate cases. These findings highlight the limitations of ABI assessment during the acute phase of ACS and indicate the need for further evaluation in this population.