Yang Changqiang, Liu Kai, Song Yue, Gong Shenzhen, Ye Runyu, Zhang Zhipeng, Chen Xiaoping
West China Hospital, Sichuan University, Chengdu, China.
West China Second University Hospital, Sichuan University, Chengdu, China.
Front Neurol. 2020 Nov 13;11:566825. doi: 10.3389/fneur.2020.566825. eCollection 2020.
Increased blood pressure variability (BPV) might be a detrimental factor after acute ischemic stroke. Previous studies on the association between blood pressure variability in the acute ischemic stroke and functional outcome have yielded inconsistent results. We aimed to investigate the impact of day-by-day blood pressure variability within 7 days of onset on functional outcome at 3 months after acute ischemic stroke. Total 367 patients hospitalized for ischemic stroke within 48 h of onset were enrolled. The acute stage of ischemic stroke was defined as the time period from symptom onset to 7 days. During this period, blood pressure was measured twice daily (respectively, in the morning during 8:00 a.m.-10:00 a.m., in the afternoon between 15:00 p.m. and 17:00 p.m.). Day-by-day blood pressure variability, including standard deviation (SD) and coefficient variation (CV) were derived and compared to functional outcome. We dichotomized function outcome according to mRS score and unfavorable outcome was defined as mRS ≥3. The patients with unfavorable outcome had significantly higher systolic BPV (within 7 days of onset) than those with favorable outcome (15.41 ± 4.59 vs. 13.42 ± 3.95 mmHg for SD, < 0.001; 11.54 ± 3.23 vs. 10.41 ± 2.82 for CV, = 0.001). Multivariable logistic regression analysis revealed that systolic BPV was significantly and independently associated with the 3-month functional outcome [odds ratio (OR) = 1.15, 95% confidence interval (CI): 1.07-1.22, < 0.001 for SD; OR = 1.15, 95% CI: 1.06-1.26, = 0.001 for CV]. In addition, After adjustment for multiple confounding factors, including age, gender, risk factors, stroke features, baseline severity, recanalized therapy, hemorrhagic transformation, pulmonary infection, white blood cell, estimated Glomerular Filtration Rate and mean BP, day-by-day BP variability was significantly correlated with an unfavorable outcome in the top vs. bottom quartile of systolic BPV (OR = 3.33, 95% CI: 1.41-7.85, = 0.006 for SD; OR = 2.27, 95% CI: 1.04-4.94, = 0.037 for CV) during 3-month follow-up. Similar trends were also observed for diastolic BPV. More importantly, incorporating SD of systolic BP into the conventional prediction model could significantly increase the AUC for prediction of 3-month unfavorable outcome after acute ischemic stroke (0.84 vs. 0.86; = 0.0416). Increased day-by-day blood pressure variability of systolic or diastolic BP in the acute ischemic stroke was associated with higher risk for unfavorable outcome at 3 months independent of blood pressure levels. Combining SD of systolic BP with conventional risk factors could improve the prediction of unfavorable outcome.
血压变异性（BPV）增加可能是急性缺血性卒中后的一个有害因素。先前关于急性缺血性卒中血压变异性与功能结局之间关联的研究结果并不一致。我们旨在研究急性缺血性卒中发病7天内每日血压变异性对发病3个月后功能结局的影响。共纳入367例在发病48小时内因缺血性卒中住院的患者。缺血性卒中的急性期定义为从症状发作到7天的时间段。在此期间，每天测量两次血压（分别在上午8:00 - 10:00以及下午15:00 - 17:00）。计算每日血压变异性，包括标准差（SD）和变异系数（CV），并与功能结局进行比较。我们根据改良Rankin量表（mRS）评分对功能结局进行二分法分类，不良结局定义为mRS≥3。不良结局患者的收缩压变异性（发病7天内）显著高于良好结局患者（标准差SD：15.41±4.59 vs. 13.42±3.95 mmHg，P<0.001；变异系数CV：11.54±3.23 vs. 10.41±2.82，P = 0.001）。多变量逻辑回归分析显示，收缩压变异性与3个月时的功能结局显著且独立相关[比值比（OR）=1.15，95%置信区间（CI）：1.07 - 1.22，SD的P<0.001；OR = 1.15，95% CI：1.06 - 1.26，CV的P = 0.001]。此外，在调整了包括年龄、性别、危险因素、卒中特征、基线严重程度、再通治疗、出血转化、肺部感染、白细胞、估计肾小球滤过率和平均血压等多个混杂因素后，在3个月随访期间，收缩压变异性最高四分位数与最低四分位数相比，每日血压变异性与不良结局显著相关（OR = 3.33，95% CI：1.41 - 7.85，SD的P = 0.006；OR = 2.27，95% CI：1.04 - 4.94，CV的P = 0.037）。舒张压变异性也观察到类似趋势。更重要的是，将收缩压标准差纳入传统预测模型可显著提高急性缺血性卒中后3个月不良结局预测的曲线下面积（AUC）（0.84 vs. 0.86；P = 0.0416）。急性缺血性卒中时收缩压或舒张压的每日血压变异性增加与3个月时不良结局风险较高相关，且独立于血压水平。将收缩压标准差与传统危险因素相结合可改善不良结局的预测。
