Association of mortality outcomes with arterial parameters derived from the 24-hour ambulatory blood pressure monitoring

Objective: Arterial stiffness, as a subclinical target organ damage, was an independent predictor of cardiovascular events. Parameters calculated from the 24-hour ambulatory blood pressure monitoring (ABPM), such as ambulatory arterial stiffness index (AASI), symmetrical AASI (sAASI), the 24-hour pulse pressure (PP) and its components expressed as elastic PP (elPP) and stiffening PP (stPP), can be used to indirectly assess arterial stiffness. Up to now, few studies have compared the associations of health outcomes with these parameters. Design and method: Out-patients who completed 24-hour ABPM (Mobil-O-Graph, Germany) at Ruijin Hospital (Shanghai, China) from 2017 to 2020 were recruited. All-cause and cardiovascular mortality (ICD10 codes I00-I99) was ascertained according to the death registry in Shanghai Municipal Center for Disease Control and Prevention. Standardized hazard ratios (HR) and 95% confidence intervals were computed with Cox regression models and adjusted for 24-hour mean arterial blood pressure and other confounders. Results: Among the 29,519 participants (mean age 52.9 years, 46.8% males) followed up for a median of 2.8 years, 244 participants died, and 78 died from cardiovascular events. In unadjusted analyses, all studied ambulatory arterial parameters were all associated with all-cause (HR, 1.41-1.87; P<0.001) and cardiovascular (HR, 1.55-2.17; P<0.001) mortality. After multivariable adjustment, AASI, the 24-hour PP, elPP and stPP remained significantly associated with all-cause (HR, 1.18-1.35; P<0.014) and cardiovascular (HR, 1.28-1.38; P<0.048) mortality, while the associations became non-significant for stPP in relation to cardiovascular death, and for sAASI with all-cause and cardiovascular outcomes. Conclusions: Arterial parameters derived from the 24-hour ABPM were independently associated with mortality outcomes, with some differences in the associations among different parameters.