Increased Mortality Associated with High Blood Pressure that Declines While Remaining Above the Normal Range
Researchers here note the phenomenon in which blood pressure declines in very late life, in the last few years. In studying a Chinese population, they find that the greatest mortality risk attends those whose blood pressure is initially high and then begins to decline while still remaining above the normal range. The consensus of recent years is that lower is better, as the raised blood pressure of hypertension causes pressure damage and disruption of normal tissue maintenance throughout the body. Study data appears to support this hypothesis. Nothing is ever simple, of course, and two different individuals can exhibit quite different degrees and manifestations of cardiovascular aging in late life.
Optimal blood pressure (BP) management strategy among the elderly remains controversial, with insufficient consideration of long-term BP trajectory. In this study, we included 11,181 participants older than 60 at baseline (mean age, 80.98 ± 10.71) with 42,871 routine BP measurements from the Chinese Longitudinal Healthy Longevity Survey. Latent class trajectory analysis and Cox proportional hazard model were conducted to identify trajectory patterns and their associations with mortality. Furthermore, we also applied mixed-effects model to identify terminal BP trajectories among the elderly.
Compared with stable at normal high level trajectory, excess systolic BP (SBP) trajectory with decreasing trend was associated with a 34% (hazard ratio, HR = 1.34) higher risk of all-cause mortality. Considering the competing risk of non-CVD death, excess BP trajectory with decreasing trend had a more pronounced effect on cardiovascular disease (CVD) mortality, in which HR was 1.67. Similar results were also found in diastolic BP (DBP), pulse pressure (PP), and mean arterial pressure (MAP) trajectories. We further conducted a mixed-effects model and observed that SBP and PP trajectories first increased and began to decline slightly six years before death. In contrast, DBP and MAP showed continuous decline 15 years before death.
In conclusion, long-term BP trajectory was associated with all-cause mortality, especially CVD mortality. Keeping a stable BP over time may be an important way for CVD prevention among the elderly.