A2102 Association between high normal ankle-brachial index and incident hypertension

Abstract

Objectives: We hypothesized that the increase in ankle-brachial index (ABI) with age occurs as a result of increasing arterial stiffness and wave reflection. The aim of this study is to investigate the relationship between ABI and incident hypertension in a screened cohort. Methods: We analyzed the data of 1344 participants without hypertension at baseline who underwent ABI measurement by an automatic oscillometric method at least twice with an interval of over a period of 36 months at health checkup, the baseline measurement in 2008–2010 and the second one in 2011–2015. Participants with ABI ≤0.9 (n = 3) and ABI ≥1.4 (n = 1) were excluded. Hypertension was defined as systolic pressure ≥140 mmHg and/or diastolic pressure ≥90 mmHg in the supine position and/or use of antihypertensive medications. Results: Mean age of participants was 51 ± 10 yeas, with a range of 19–80 years, and 55% were women. ABI was lowest in participants aged less than 40 years, and increased with age in both sexes. At the second visit (median 47 months follow-up period), 224 (17%) participants developed hypertension. Baseline ABI was positively correlated with the rates of change in brachial systolic pressure and incident hypertension. Compared with participants with the lowest quartile of baseline ABI, the adjusted odds ratio for incident hypertension was higher in participants with the highest quartile of baseline ABI before and after multivariate adjustment for age, sex, baseline systolic pressure, heart rate, brachial-ankle pulse wave velocity (baPWV), BMI, prevalence of diabetes, dyslipidemia, and low eGFR (<60 ml/min/1.73m2) (odds ratio 2.1, 95% confidence interval 1.19 to 3.61, P = 0.010). Conclusion: Baseline ABI was positively and independently associated with the rate of SBP change and incident hypertension.