Relationship of Arterial Stiffness Index and Pulse Pressure With Cardiovascular Disease and Mortality

BACKGROUND Vascular aging results in stiffer arteries and may have a role in the development of cardiovascular disease (CVD). Arterial stiffness index (ASI), measured by finger photoplethysmography, and pulse pressure (PP) are 2 independent vascular aging indices. We investigated whether ASI or PP predict new-onset CVD and mortality in a large community-based population. METHODS AND RESULTS We studied 169 613 UK Biobank participants (mean age 56.8 years; 45.8% males) who underwent ASI measurement and blood pressure measurement for PP calculation. Mean±SD ASI was 9.30±3.1 m/s and mean±SD PP was 50.98±13.2 mm Hg. During a median disease follow-up of 2.8 years (interquartile range 1.4-4.0), 18 190 participants developed CVD, of which 1587 myocardial infarction (MI), 4326 coronary heart disease, 1192 heart failure, and 1319 stroke. During a median mortality follow-up of 6.1 years (interquartile range 5.8-6.3), 3678 participants died, of which 1180 of CVD. Higher ASI was associated with increased risk of overall CVD (unadjusted hazard ratio 1.27; 95% confidence interval [CI], 1.25-1.28), myocardial infarction (1.38; 95% CI, 1.32-1.44), coronary heart disease (1.31; 95% CI, 1.27-1.34), and heart failure (1.31; 95% CI 1.24-1.37). ASI also predicted mortality (all-cause, CVD, other). Higher PP was associated with overall CVD (1.57; 95% CI, 1.55-1.59), myocardial infarction (1.48; 95% CI, 1.42-1.54), coronary heart disease (1.47; 95% CI, 1.43-1.50), heart failure (1.47; 95% CI, 1.40-1.55), and CVD mortality (1.47; 95% CI, 1.40-1.55). PP improved risk reclassification of CVD in a non-laboratory-based Framingham Risk Score by 5.4%, ASI by 2.3%. CONCLUSIONS ASI and PP are independent predictors of CVD and mortality outcomes. Although both improved risk prediction for new-onset disease, PP appears to have a larger clinical value than ASI.