Longitudinal change in blood pressure is associated with cardiovascular disease mortality in a Chinese cohort

Abstract

Background A number of studies have demonstrated a J-shaped curve between blood pressure and all-cause mortality, but few studies have used longitudinal change in blood pressure to study mortality in the Chinese population. Methods We performed a 30-year follow-up study to examine the association between blood pressure (at baseline and longitudinal change) and risk of mortality in the Linxian General Population Trial Cohort. At baseline, a total of 29,584 healthy adults were enrolled in the Linxian General Population Trial in 1985 and followed through the end of 2014. The final analysis was restricted to 29,439 participants(55% women) after exclusion of outliers. We also examined the potential effects of BP trajectory patterns during the period of 1985-1999 on sequent risk of mortality. Adjusted Cox proportional hazards models were used to estimate hazard ratios(HRs) and 95% confidence intervals(95%CIs). Results Compared to participants with normal blood pressure, patients with prehypertension, stage 1, stage 2, or stage 3 hypertension had an increased risk of all-cause mortality, with HRs of 1.09(1.05-1.14), 1.34(1.28-1.40), 1.69(1.60-1.79) and 2.14(2.01-2.28), respectively. Relative to stable BP of normotension, having a rise in BP from normotension to hypertension or from prehypertension to hypertension both conferred an increased risk of total and cardiovascular disease and stroke mortality (Total: HRs=1.22(1.12-1.34) and 1.36(1.23-1.51); Cardiovascular disease: HRs=1.42(1.17-1.73) and 1.55(1.24-1.93); Stroke: HRs=2.29(1.88-2.80) and 2.61(2.11-3.24), respectively). Conclusions These findings emphasize that development of incident hypertension in middle age could increase the risk of total, cardiovascular disease, and stroke mortality, and suggest that current blood pressure targets could be revised.

Baseline and longitudinal change in blood pressure and mortality in a Chinese cohort

“…A pooled analysis of seven cohorts from Norway, Austria and Sweden has suggested a higher risk of cancer mortality with the elevated BP 25. However, there is little support for hypertension and cancer incidence risk in a Swedish Trial of old patients22 and a recent Chinese study from the Linxian Nutrition Intervention Trial 12. Several mechanisms may explain the inverse associations observed for cancer in our study.…”

“…BP change over time may have greater power in predicting total and cardiovascular mortality. Limited studies in China have examined the potential effect of change in BP 12. In our study, we included subjects with at least two measurements of BP to examine the potential effect of BP change.…”

“…A recent study in Chinese normotensive people with diabetes showed that low BP or a decline in BP was associated with an increased risk of all-cause mortality,10 and Tielemans et al 11 and Fan et al 12 also demonstrated that BP trajectories were strong predictors of all-cause mortality. Although previous studies have examined the association between BP change and risk of mortality, most studies have been conducted in Western populations and the findings remain unclear.…”

Short‐term blood pressure changes have a more strong impact on stroke and its subtypes than long‐term blood pressure changes

“…Previous studies have confirmed and reinforced the importance of BP change by different forms for stroke. Limited prospective studies in the form of longitudinal elevated or decreased BP trajectories at several time points have emphasized that increase in BP is a major risk factor for adverse outcomes of CVD (including stroke) in China or Western countries . Another form of BP changes is the visit‐to‐visit blood pressure variability, and studies have found that higher variability of BP or SBP is a powerful predictor of cardiovascular events independently of mean SBP or DBP, which has been more common in previous studies .…”

“…Dynamic BP changes include more critical information for prediction of stroke risk, having higher accuracy and sensitivity . Several lines of evidence that visit‐to‐visit variability (VVV) of BP or trajectory changes in BP are associated with a higher incidence of CVD and a higher risk of mortality . However, few studies have concentrated on the effects of BP changes on stroke and its subtypes, and most of those studies were conducted either in Western countries or focused on the adverse outcomes affected by BP changes during the same time period or same multiple time periods .…”