1 Institute of Cardiovascular and Medical Sciences, Queen Elizabeth University Hospital, University of Glasgow, Glasgow, UK.
2 Brain Research Imaging Centre, The University of Edinburgh, Edinburgh, UK.
Int J Stroke. 2018 Jul;13(5):473-480. doi: 10.1177/1747493017729267. Epub 2017 Sep 5.
Higher blood pressure, blood pressure variability, and leukoaraiosis are risk factors for early adverse events and poor functional outcome after ischemic stroke, but prior studies differed on whether leukoaraiosis was associated with blood pressure variability, including in ischemic stroke. In the Third International Stroke Trial, blood pressure was measured in the acute phase of ischemic stroke immediately prior to randomization, and at 0.5, 1, and 24 h after randomization. Masked neuroradiologists rated index infarct, leukoaraiosis, and atrophy on CT using validated methods. We characterized blood pressure variation by coefficient of variance and three other standard methods. We measured associations between blood pressure, blood pressure variability, and leukoaraiosis using generalized estimating equations, adjusting for age, and a number of covariates related to treatment and stroke type/severity. Among 3017 patients, mean (±SD) systolic and diastolic blood pressure decreased from 155(±24)/82(±15) mmHg pre-randomization to 146(±23)/78(±14) mmHg 24 h later ( P < 0.005). Mean within-subject coefficient of variance was 0.09 ± 0.05 for systolic and 0.11 ± 0.06 for diastolic blood pressure. Patients with most leukoaraiosis were older and had higher blood pressure than those with least ( P < 0.0001). Although statistically significant in simple pairwise comparisons, no measures of blood pressure variability were associated with leukoaraiosis when adjusting for confounding variables ( P > 0.05), e.g. age. Our results suggest that blood pressure variability is not a potential mechanism to explain the association between leukoaraiosis and poor outcome after acute stroke.
更高的血压、血压变异性和脑白质疏松症是缺血性中风后早期不良事件和功能预后不良的危险因素，但先前的研究结果在脑白质疏松症是否与血压变异性相关方面存在差异，包括在缺血性中风中。在第三次国际中风试验中，在随机分组前的缺血性中风急性期测量血压，并在随机分组后 0.5、1 和 24 小时测量血压。蒙面神经放射学家使用经过验证的方法对 CT 上的指数梗死、脑白质疏松症和萎缩进行评分。我们使用广义估计方程来描述血压变化的变异系数和其他三种标准方法，调整年龄和与治疗和中风类型/严重程度相关的许多协变量。在 3017 名患者中，收缩压和舒张压从随机分组前的 155(±24)/82(±15)mmHg 降至 24 小时后的 146(±23)/78(±14)mmHg（P<0.005）。收缩压和舒张压的平均个体内变异系数分别为 0.09±0.05 和 0.11±0.06。脑白质疏松症最严重的患者比最不严重的患者年龄更大，血压更高（P<0.0001）。尽管在简单的两两比较中具有统计学意义，但在调整混杂变量后，血压变异性的任何测量指标与脑白质疏松症均无相关性（P>0.05），例如年龄。我们的结果表明，血压变异性不是解释急性中风后脑白质疏松症与不良预后之间关联的潜在机制。
