Blood pressure was measured at the posterior tibial artery by Doppler ultrasonography in 124 elderly subjects (37 men and 87 women) living in two retirement homes in Naples (Italy). Ankle-to-arm systolic pressure ratios below 0.97 and 0.90 was considered as a probable and definite pathological sign of peripheral arterial disease, respectively. Half of the subjects (48% of men and 51% of women) gave a value below 0.97, while a third (35% of men and 33% of women) had a value below 0.90. By multiple regression analysis, mean blood pressure, plasma cholesterol levels and cigarette smoking were all negatively correlated with ankle systolic pressure values with a progressively lower significance. Most of the patients with pathological Doppler examination were asymptomatic at a questionnaire for intermittent claudication.