The ankle-arm blood pressure index is strongly predictive for cardiovascular mortality in men

In recent years some reports suggested that the presence of peripheral arterial disease (PAD) or a decrease in the ankle-arm blood pressure index (AAI) are associated with a substantial increase in cardiovascular mortality. The end-point of the study was to evaluate whether the AAI is an independent predictor of mortality in adult men. Date and cause of death were ascertained for a cohort of 215 male outpatients who underwent ultrasonographic examination of lower extremity circulation in the Noninvasive Vascular Diagnostic Laboratory of our University Department. The study was designed over a 10-year period of observation: total and cardiovascular mortality were considered. An AAI of 0.90 or less was selected as cutpoint for the definition of PAD. The death rates were significantly higher among patients with PAD than in normal subjects. After adjusting for age and other covariates (Cox proportional-hazards models), the baseline AAI was strongly, independently, inversely correlated with all-cause mortality (relative risk = 0.09, 95% confidence interval /CI/ = 0.03-0.3), cardiovascular disease mortality (relative risk = 0.02, 95% CI = 0.001-0.15) and ischemic heart disease mortality (relative risk = 0.03, 95% CI = 0.005-0.24). The independent association did not change after the exclusion of patients with history of previous cardiovascular events at baseline and after excluding patients who survived one year or less since the baseline evaluation. Our results confirm that a decreased AAI is associated with a substantial increase in cardiovascular mortality. Routine evaluation of the AAI could be of help for identifying high risk patients.