Ankle-arm index as an indicator of atherosclerosis: its application as a screening method

The ankle-arm blood pressure index (AAI) is seldom used to screen for atherosclerotic diseases other than lower extremity arterial disease. This study was conducted to investigate whether the AAI can be used as a screening test for atherosclerotic diseases in general. The subjects were 446 male workers in a copper smelter. Fundoscopic examinations, electrocardiograms, serum cholesterol and triglyceride measurements, and AAI measurements were conducted. Information on past medical histories of diabetes mellitus and ischemic heart disease, smoking, alcohol intake, duration of sleep and physical activity were collected. The AAI correlated well with the results of the fundoscopic examinations, and an AAI of 1.00 gave the maximum sensitivity specificity product. The same AAI value also gave the maximum products for ST segment depression in electrocardiograms and the past history of ischemic heart disease. Multiple logistic regression analysis showed that a low AAI value was related to higher systolic blood pressure and current smoking but was inversely related to alcohol intake. Our study validated the AAI in predicting persons with risk factors of atherosclerotic diseases. The AAI measurements can be conducted at low cost, using simple techniques, and are noninvasive. We propose that the AAI be widely used to screen for atherosclerotic diseases.