Department of Epidemiology, University of Washington, Seattle, Washington;
Am J Hypertens. 2013 Oct;26(10):1210-7. doi: 10.1093/ajh/hpt092. Epub 2013 Jun 6.
Recent reports have linked variability in visit-to-visit systolic blood pressure (SBP) to risk of mortality and stroke, independent of the effect of mean SBP level. This study aimed to evaluate whether variability in SBP is associated with all-cause mortality, incident myocardial infarction (MI), and incident stroke, independent of mean SBP or trends in SBP levels over time.
The Cardiovascular Health Study is a longitudinal cohort study of vascular risk factors and disease in the elderly. Participants who attended their first 5 annual clinic visits and experienced no event before the 5th visit were eligible (n = 3,852). Primary analyses were restricted to participants not using antihypertensive medications throughout the first 5 clinic visits (n = 1,642). Intraindividual SBP variables were defined using each participant's 5-visit blood pressure measures. Cox proportional hazards models estimated adjusted hazard ratios (HRs) per SD increase in intraindividual SBP variability, adjusted for intraindividual SBP mean and change over time.
Over a mean follow-up of 9.9 years, there were 844 deaths, 203 MIs, and 195 strokes. Intraindividual SBP variability was significantly associated with increased risk of mortality (HR = 1.13; 95% confidence interval (CI) = 1.05-1.21) and of incident MI (HR = 1.20; 95%CI = 1.06-1.36), independent of the effect from adjustment factors. Intraindividual SBP variability was not associated with risk of stroke (HR = 1.03; 95% CI = 0.89-1.21).
Long-term visit-to-visit SBP variability was independently associated with a higher risk of subsequent mortality and MI but not stroke. More research is needed to determine the relationship of BP variability with cardiovascular risk and the clinical implications.
最近的报告表明，收缩压（SBP）的随访间变异性与死亡率和卒中风险相关，独立于平均 SBP 水平的影响。本研究旨在评估 SBP 的变异性是否与全因死亡率、新发心肌梗死（MI）和新发卒中相关，独立于平均 SBP 或 SBP 水平随时间的趋势。
心血管健康研究是一项针对老年人血管危险因素和疾病的纵向队列研究。符合条件的参与者需参加前 5 次年度临床就诊，且在第 5 次就诊前无任何事件（n = 3852）。主要分析仅限于在首次 5 次就诊期间未使用抗高血压药物的参与者（n = 1642）。采用每位参与者的 5 次就诊血压测量值定义个体内 SBP 变量。使用 Cox 比例风险模型估计个体内 SBP 变异性每增加一个标准差的调整后危险比（HR），调整了个体内 SBP 平均值和随时间的变化。
平均随访 9.9 年后，发生 844 例死亡、203 例 MI 和 195 例卒中。个体内 SBP 变异性与死亡率（HR = 1.13；95%置信区间[CI] = 1.05-1.21）和新发 MI（HR = 1.20；95%CI = 1.06-1.36）的风险增加显著相关，独立于调整因素的影响。个体内 SBP 变异性与卒中风险无关（HR = 1.03；95%CI = 0.89-1.21）。
长期随访间 SBP 变异性与随后的死亡率和 MI 风险增加独立相关，但与卒中风险无关。需要进一步研究以确定 BP 变异性与心血管风险的关系及其临床意义。
