Systolic Blood Pressure Variability and All-Cause and Cause-Specific Mortality: A Multi-Center Cohort Study of 1.4 Million Older Adults

Objective: While long-term blood pressure variability (BPV) is an independent risk factor for all-cause and cardiovascular mortality, the real world applicability remains underexplored, especially in older populations. We aimed to evaluate the association between visit-to-visit systolic blood pressure (SBP) variability and risks of all-cause and cardiovascular mortality in a large-scale multicenter cohort of Chinese older adults.Design and method: This study was based on the Multi-city Elderly Health Examination Cohort Study, which correlated elderly health management data from the Basic Public Health Services Project with mortality information from the China Population Death Information Registration System. We analyzed 1,473,648 individuals (mean age 72.97±5.56 years; 53.9% female). SBP variability was assessed using average real variability (ARV) based on three blood pressure measurements between 2017 to 2023. Follow-up began from the last SBP measurement to death or December 31, 2023. Participants were categorized into ARV quintiles, with the second quintile (Q2) as the reference. Multivariable Cox proportional hazards models were employed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality, adjusting for demographics, lifestyle factors, baseline comorbidities, and mean SBP. Fine-Gray competing risk models and wash-out period were applied to ensure the robustness of the findings. Results: During a mean follow-up of 2.7 years, 105,856 deaths occurred, including 47,414 from cardiovascular diseases (CVDs). J-shaped relationship was observed between ARV and all-cause and CVDs mortality (Pnon-linear<0.001), where the highest ARV quintile (Q5) exhibited significant increase in risk of mortality (HRall-cause:1.14, 95%CI: 1.12-1.16; HRcvd:1.19, 95%CI: 1.15-1.22) compared to Q2. These relationships remain robust in Fine-Gray competing risk models and after excluding deaths within the first year of follow-up. Subgroup analysis confirmed adverse effects of high BPV across sex, age, BMI, mean SBP and baseline comorbidities. Conclusions: Visit-to-visit SBP variability exhibits a J-shaped association with both all-cause and CVDs mortality among older adults. These findings suggest that both high and excessively low BPV increased mortality risk. Therefore, managing an optimal range of blood pressure fluctuations, in addition to achieving target SBP, may be a crucial strategy for enhancing longevity in the elderly population.