A prospective study on the association between hypertension, high-normal blood pressure, and life expectancy in middle-aged and elderly Chinese adults: findings from the China Health and Retirement Longitudinal Study (CHARLS)

This study aims to investigate the association between different blood pressure levels and all-cause mortality, as well as their impact on life expectancy, among middle-aged and elderly Chinese adults. The data from China Health and Retirement Longitudinal Study (CHARLS) (2011–2020) was used. Participants with complete baseline and follow-up data was included in this analysis. According to the baseline blood pressure participants were categorized into three groups: normal blood pressure, high-normal blood pressure, and hypertension. The Cox proportional hazards regression model was employed to assess the impact of different blood pressure levels on all-cause mortality risk and the model with age as the time scale was used to estimate the life expectancy gap. This study included a total of 9,972 participants aged 45 and above, comprising 4,924 males and 5,048 females. After multivariable adjustment, compared to the normal blood pressure, the hazard ratios (HRs) for all-cause mortality in the high-normal blood pressure and hypertension groups were 1.14 (95% CI: 0.97–1.34) and 1.69 (95% CI: 1.46–1.95), respectively. Life expectancy analysis indicated that, compared to individuals with normal blood pressure, the years of life lost due to high-normal blood pressure and hypertension were 2.26 (95% CI: 2.05–2.45) and 5.75 (95% CI: 5.54–5.96) years at age 45, 2.19 (95% CI: 2.05–2.35) and 5.46 (95% CI: 5.31–5.63) years at age 55, and 2.05 (95% CI: 1.94–2.16) and 4.79 (95% CI: 4.68–4.89) years at age 65. Sex-stratified analysis revealed that hypertension was associated with a greater reduction in life expectancy among females, whereas high-normal blood pressure had a more pronounced impact on males. Sensitivity analyses yielded results consistent with the primary analysis, further confirming the robustness of the study findings. This study confirms that in the middle-aged and elderly population in China, hypertension is significantly associated with an increased risk of all-cause mortality. Both high-normal blood pressure and hypertension lead to a reduction in life expectancy, with noticeable gender differences. These findings underscore the importance of early intervention for individuals with hypertension, even when blood pressure is in the high-normal range. Additionally, it is crucial to develop precise intervention strategies tailored to gender differences to reduce the burden of cardiovascular diseases and improve the overall health of the Chinese population.