Cardiovascular morbidity-mortality associated to ankle-brachial index in the general population

Background and objectives: Abnormal ankle-brachial index (ABI) is associated with a high risk of cardiovascular disease. This study has aimed to investigate the association between low ABI and risk of cardiovascular death in a general population attended in a primary care center.

Patients and methods: A total of 1,361 volunteers aged between 60 and 79 years without any evidence of peripheral artery disease who attended a primary care center participated in the study. They underwent a complete physical examination, together with standard blood tests and ABI was determined. The participants were contacted by telephone 4 years later and asked about any cardiovascular problems for that period. Causes of death and hospitalization were confirmed in the medical records in the primary care center and/or hospital.

Results: Information was obtained about the clinical evolution of 1,300 participants (mean age 69.9 years, 38.2% men). Mean follow-up was 49.8 months. There were 13 cardiovascular death and 49 major cardiovascular events. Low ABI (<0.9) was associated with a significant higher risk of cardiovascular death (adjusted relative risk 6.83; 95% confidence interval 1.36-34.30, P=.020), and with a higher risk of major cardiovascular events (adjusted relative risk 2.42; 95% confidence interval 0.99-5.91, P=.051). High or uncompressible ABI was not associated with higher cardiovascular risk.

Conclusions: A low ABI was associated with higher risk of cardiovascular death in the general population followed-up in a primary care center.