Ankle-arm blood pressure index as a correlate of preclinical carotid atherosclerosis in elderly Japanese men

Peripheral artery disease correlates with preclinical carotid atherosclerosis in Western populations. However, little is known about this correlation in Asian populations. In a cross-sectional population-based study, we examined the correlation between peripheral arterial disease and carotid intima-media thickness (IMT) among 726 Japanese men aged 60–79 years. None of them had a history of clinical peripheral arterial disease. The ankle-to-arm systolic blood pressure index (AAI) was used as a surrogate estimate of peripheral arterial disease. Compared to men with AAI ≥ 0.90, those with AAI < 0.90 were 1–4 years older, and had lower mean body mass index and higher prevalence of current smokers. The mean AAI correlated inversely and linearly with maximum IMT in the common and internal carotid arteries (CCA and ICA), and men with AAI < 0.90 had higher prevalence of maximum ICA IMT ≥1.5 mm than did those with AAI ≥ 0.90. The multivariate odds ratio (95% confidence interval) of maximum ICA IMT ≥1.5 mm was 2.9 (1.0–8.4), while that of maximum CCA IMT ≥ 1.1 mm was 1.4 (0.5–3.8) for men with AAI < 0.90 versus ≥ 1.30. The sensitivity was 65% and the specificity was 98% for low AAI to detect ICA IMT ≥1.5 mm. Low AAI is a strong correlate for internal carotid atherosclerosis and the AAI measurement may be of use to screen for preclinical peripheral atherosclerosis among Japanese elderly men.