Dawson S L, Manktelow B N, Robinson T G, Panerai R B, Potter J F
University Departments of Medicine for the Elderly, The Glenfield Hospital, Leicester General Hospital, Leicester, UK.
Stroke. 2000 Feb;31(2):463-8. doi: 10.1161/01.str.31.2.463.
In hypertensive populations, increasing blood pressure (BP) levels and BP variability (BPV) are associated with a greater incidence of target organ damage. After stroke, elevated 24-hour BP levels predict a poor outcome, although it is uncertain whether shorter-length BP recordings assessing mean BP levels and BPV have a similar predictive role. The objectives of this study were to compare the different measures of beat-to-beat BP and BPV on outcome after acute ischemic stroke and assess whether these parameters were affected by stroke subtype.
Ninety-two consecutive admissions with a CT-confirmed diagnosis of acute ischemic stroke were recruited, of whom 54 had cortical infarction, 29 subcortical, and 9 posterior circulation infarction. Casual and two 5-minute recordings of beat-to-beat BP (Finapres, Ohmeda) were made under standardized conditions within 72 hours of ictus, with mean BP levels taken as the average of this 10-minute recording and BPV as the standard deviation. Outcome was assessed at 30 days as dead/dependent or independent (Rankin </=2). The effects of BP, BPV, and stroke subtype on outcome were studied with the use of logistic regression. Stroke subjects were subsequently divided by BP quartiles and within each quartile into low- and high-variability groups; the influence of high BPV on outcome was also assessed.
The odds ratio for death/dependency was significantly higher in cortical strokes compared with subcortical and posterior circulation strokes even after controlling for differences in BP and BPV (OR 4.19, P=0.002). Beat-to-beat systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP +/- SD) levels were higher in the dead/dependent group compared with the independent group (MAP 106+/-20.4 mm Hg vs 97+/-19.1 mm Hg, P<0.02), as was MAP variability: 6.1 (interquartile range 4.5 to 7.4 mm Hg) versus 4.9 (3.8 to 6.4 mm Hg, P=0.02). The odds ratio for a poor outcome was 1. 38 (P=0.014) for every 10-mm Hg increase in MAP and 1.32 (P=0.02) for every 1-mm Hg increase in MAP variability. Casual BP measurements had no prognostic significance. For the group as a whole when separated into BP quartiles, those with a high MAP and DBP but not SBP variability within each quartile had a worse prognosis compared with those with a low BPV.
A poor outcome at 30 days after ischemic stroke was dependent on stroke subtype, beat-to-beat DBP, and MAP levels and variability. Important prognostic information can be readily obtained from a short period of noninvasive BP monitoring in the acute stroke patient. These findings have important implications, particularly regarding the use of hypotensive agents in the acute stroke period.
在高血压人群中，血压（BP）水平升高及血压变异性（BPV）增加与靶器官损害发生率升高相关。卒中后，24小时血压水平升高预示预后不良，尽管评估平均血压水平和BPV的较短时长血压记录是否具有类似预测作用尚不确定。本研究的目的是比较急性缺血性卒中后逐搏血压和BPV的不同测量指标对预后的影响，并评估这些参数是否受卒中亚型影响。
连续纳入92例经CT确诊的急性缺血性卒中患者，其中54例为皮质梗死，29例为皮质下梗死，9例为后循环梗死。在发病72小时内，于标准化条件下进行一次随机及两次5分钟的逐搏血压（Finapres，Ohmeda）记录，平均血压水平取该10分钟记录的平均值，BPV取标准差。在30天时评估预后，分为死亡/依赖或独立（Rankin≤2）。采用逻辑回归研究血压、BPV和卒中亚型对预后的影响。随后将卒中患者按血压四分位数分组，并在每个四分位数内分为低变异性组和高变异性组；还评估了高BPV对预后的影响。
即使在控制了血压和BPV差异后，皮质卒中患者死亡/依赖的比值比仍显著高于皮质下和后循环卒中患者（比值比4.19，P = 0.002）。死亡/依赖组的逐搏收缩压（SBP）、舒张压（DBP）和平均动脉压（MAP±SD）水平高于独立组（MAP 106±20.4 mmHg对97±19.1 mmHg，P < 0.02），MAP变异性也是如此：6.1（四分位数间距4.5至7.4 mmHg）对4.9（3.8至6.4 mmHg，P = 0.02）。MAP每升高10 mmHg，预后不良的比值比为1.38（P = 0.014），MAP变异性每升高1 mmHg，比值比为1.32（P = 0.02）。随机血压测量无预后意义。对于总体患者，按血压四分位数分组后，每个四分位数内MAP和DBP高但SBP变异性低的患者与BPV低的患者相比，预后更差。
缺血性卒中后30天预后不良取决于卒中亚型、逐搏DBP、MAP水平及变异性。在急性卒中患者中，通过短期无创血压监测可轻易获得重要的预后信息。这些发现具有重要意义，尤其是在急性卒中期使用降压药物方面。
