Pathological ankle-brachial index is equivalent of advanced age in acute coronary syndromes

Abstract

Background: Age is one the factors associated with poor prognosis in acute coronary syndromes (ACS) and elderly patients are a high-risk collective with few parameters for mid-term cardiovascular stratification. We aimed to assess the predictive value of ankle-brachial index (ABI) in patients (> 75 years) for 1-year mortality after an ACS.

Materials and methods: Prospective, observational and multicentre study of ACS patients in whom ABI was assessed during hospitalization.

Results: A total of 1·054 patients were included, mean age 66·6 (11·7) years from whom 26·6% were > 75 years. Elderly patients showed more history of cardiovascular disease and higher prevalence of all risk factors, except current smoking. Angiography and revascularization were performed less frequently in the elderly. Patients > 75 years showed higher presence of three vessel coronary disease and received fewer guideline-recommended treatments. Patients who died through the follow-up, mean time 387·9 ± 7·2 days, had lower ABI (0·73 ± 0·24 vs. 0·92 ± 0·22; P < 0·01), also in the elderly patients (0·73 ± 0·24 vs. 0·86 ± 0·23; P < 0·01). Cox regression analysis identified age > 75 years (HR: 2·30; IC 95% 1·26-4·18; P < 0·01) and ABI < 0·90 (HR: 3·58; IC 95% 1·80-7·15; P < 0·01) as risk factors for to 1-year mortality. Mortality was similar in elderly patients with ABI > 0·90 and young patients with ABI < 0·90; the worst prognosis was observed in elderly patients with ABI < 0·90 (HR: 10·01; 95% CI 3·74-27·15).

Conclusions: Elderly patients represent a relevant collective of patients with ACS and are treated less optimally. ABI predicts 1-year mortality after an ACS in elderly patients.