The variability of ankle–arm blood pressure difference and ankle–brachial index in treated hypertensive patients

The purpose of this study was to investigate whether ankle–arm blood pressure (BP) difference (An–a) and ankle–brachial index (ABI) are consistent in treated hypertensive patients with obvious BP variation. This study enrolled 414 hypertensive patients (200 males; mean age, 61.3 ± 13.3 years) admitted to our hospital. BP of four limbs was simultaneously measured using four automatic BP measurement devices on the day of admission, and three and six day after admission. The An-a differences on systolic BP (SBP), diastolic BP (DBP), mean artery pressure (MAP), and pulse pressure (PP) in both sides were calculated, respectively. The relative decrease amplitude (RDA) of BP was calculated using the formula: RDA = (BP1 − BPn)/BP1. The ABI of the right side was calculated. From the first to the third measurement, arm SBP and DBP levels of both arms significantly decreased (right arm: SBP: 163.7 ± 18.4, 147.7 ± 15.3 vs. 135.4 ± 11.7 mm Hg; P < .05; DBP: 86.6 ± 13.4, 79.9 ± 11.6 vs. 74.5 ± 9.6 mm Hg; P < .05); at the same time, the ankle SBP (right ankle: 182.1 ± 22.1, 147.7 ± 15.3 vs. 153.4 ± 16.6 mm Hg; P < .05) and DBP (84.8 ± 13.4, 79.9 ± 11.6 vs. 75.8 ± 9.8 mm Hg; P < .05) of both sides also significantly decreased. The mean An–a of three measurements of both sides was consistent at the levels of about 20 mm Hg on SBP and PP, 7 mm Hg on MAP, and 0 mm Hg on DBP. However, sABI gradually increased from the first to the third measurement.In treated hypertensive patients, the An–a differences on SBP, DBP, PP, and MAP are generally consistent, but sABI is associated with underlying SBP levels.