Impact of high blood pressure on the risk of mortality among Japanese people aged 65 years and older

Abstract

Aim: The purpose of this study is to investigate the impact of abnormal blood pressure on the risk of all-cause and cardiovascular mortality in a large cohort of older Japanese people aged ≥65 years. Methods: This cohort study enrolled 54 760 participants from Okayama City aged ≥65 years who underwent basic health checkups from April 2006 to March 2008. Based on blood pressure, the participants were divided into six categories, from C1 (lowest) to C6 (highest). To assess the association of blood pressure with all-cause and cardiovascular mortality, we used survival analysis to estimate hazard ratios (HRs) for all-cause mortality and subdistribution HRs (SHRs) for cardiovascular mortality on C3. We then repeated the analyses based on age groups (65–74 years, 75–84 years, and ≥85 years). Results: The fully adjusted HRs for all-cause mortality, which included all individual potential confounders, were 1.11 (95% confidence interval [CI]: 1.04–1.19) for C5 and 1.23 (95% CI: 1.09–1.38) for C6, respectively. The fully adjusted SHRs for cardiovascular mortality were 1.11 (95% CI: 1.01–1.21) for C4, 1.19 (95% CI: 1.05–1.34) for C5, and 1.36 (95% CI: 1.09–1.70) for C6. In the age-stratification, an increased risk of hypotension was observed with older age. The HR for C1 was 1.28 (95% CI: 1.16–1.41) for ≥85 years. Conclusions: Hypertension increased the risk of all-cause and cardiovascular mortality among those aged 65–74 and 75–84 years, but not among those aged ≥85 years. Geriatr Gerontol Int 2025; 25: 82–89.