Abstract P531: Contralateral Differences in Ankle Systolic Blood Pressure and Pulse Wave Velocity: Associations With Incident Heart Failure and Mortality

Introduction: Contralateral differences in systolic blood pressure (SBP) are a risk assessment tool and indicative of underlying cardiovascular issues. Most of the available studies focused on brachial blood pressure and its clinical impact. This study evaluated whether interankle SBP differences and contralateral differences in pulse wave velocity (PWV) are associated with incident heart failure (HF) and all-cause and cardiovascular mortality in a community-dwelling sample of older adults. Methods: Sample included 5,077 participants (75.2 ± 5.1 years old) of the Atherosclerosis Risk in Communities (ARIC) study. The OMRON VP-1000 plus was used to measure PWV and blood pressure in the ankles. PWV was assessed between the brachial artery and ankle (baPWV) and heart and ankle (haPWV) on the right and left sides. Cut points for contralateral differences in PWV were set at the 90th percentile in our sample. Outcomes included incident HF (first definite or probable hospitalization for acute decompensated HF), all-cause and cardiovascular mortality (until December 31, 2020). Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). Results: Over a mean follow-up of 7.5 ± 2.1 years, incident HF was diagnosed in 457 participants, and 1,275 all-cause and 363 cardiovascular deaths occurred. The prevalence of interankle SBP difference ≥10 and ≥15 mmHg was 24.9% (1,268) and 12.0% (605), respectively. The prevalence of contralateral differences in baPWV (>240 cm/s) and haPWV (>80 cm/s) was 10.1% (513) and 9.1% (464), respectively. Interankle SBP difference ≥10 mmHg (HR 1.13; 95% CI 1.00-1.29), ≥15 mmHg (HR 1.25; 95% CI 1.06-1.48), contralateral difference in baPWV >240 cm/s (HR 1.18; 95% CI 1.00-1.41), and haPWV >80 cm/s (HR 1.21; 95% CI 1.01-1.44) were each independently associated with all-cause mortality after adjustment for demographics, traditional cardiovascular risk factors, and extreme values of ankle-brachial index ≤0.9 or >1.40. Contralateral differences in ankle SBP ≥15 mmHg (HR 1.55; 95% CI 1.16-2.06), and haPWV >80 cm/s (HR 1.40; 95% CI 1.02-1.91) were both independently associated with cardiovascular mortality. Crude analysis revealed that those with contralateral differences in ankle SBP ≥10 and ≥15 mmHg, baPWV >240 cm/s, and haPWV >80 cm/s had a significantly higher risk of HF (p<0.05 for all). However, these HF relationships were no longer statistically significant after adjustment for confounders. Conclusions: Contralateral differences in ankle SBP and PWV were independently associated with all-cause and cardiovascular mortality risk even after accounting for traditional cardiovascular risk factors and the ankle-brachial index. These results underscore the significance of evaluating contralateral differences in ankle SBP and PWV as potential markers of increased mortality risk among older adults.