Department of Internal Medicine, University of Perugia, Italy.
J Hypertens. 2011 Jul;29(7):1253-69. doi: 10.1097/HJH.0b013e3283469976.
Guidelines generally recommend intensive lowering of blood pressure (BP) in patients with type 2 diabetes. There is uncertainty about the impact of this strategy on case-specific events. Thus, we generated estimates of the effects of BP reduction on the risk of myocardial infarction (MI) and stroke in diabetic patients.
We selected studies which compared different BP-lowering agents and different BP intervention strategies in patients with diabetes. Outcome measures were MI and stroke. We abstracted information about study design, intervention, population, outcomes, and methodological quality for a total of 73,913 patients with diabetes (295,652 patient-years of exposure) randomized in 31 intervention trials.
Overall, experimental treatment reduced the risk of stroke by 9% (P = 0.0059), and that of MI by 11% (P = 0.0015). Allocation to more-tight, compared with less-tight, BP control reduced the risk of stroke by 31% [relative risk (RR) 0.61, 95% confidence interval (CI) 0.48-0.79], whereas the reduction in the risk of MI approached, but did not achieve, significance [odds ratio (OR) 0.87, 95% CI 0.74-1.02]. In a meta-regression analysis, the risk of stroke decreased by 13% (95% CI 5-20, P = 0.002) for each 5-mmHg reduction in SBP, and by 11.5% (95% CI 5-17, P < 0.001) for each 2-mmHg reduction in DBP. In contrast, the risk of MI did not show any association with the extent of BP reduction (SBP: P = 0.793; DBP: P = 0.832).
In patients with diabetes, protection from stroke increases with the magnitude of BP reduction. We were unable to detect such a relation for MI.
指南通常建议 2 型糖尿病患者积极降低血压（BP）。但对于该策略对具体病例事件的影响尚存在不确定性。因此，我们评估了降低 BP 对糖尿病患者心肌梗死（MI）和卒中风险的影响。
我们选择了比较不同降压药物和不同降压干预策略在糖尿病患者中的研究。主要终点为 MI 和卒中。我们提取了研究设计、干预、人群、结局和方法学质量等信息，共有 31 项干预试验的 73913 例糖尿病患者（295652 人年的暴露）被随机分组。
总体而言，实验组卒中风险降低 9%（P=0.0059），MI 风险降低 11%（P=0.0015）。与血压控制较松相比，更严格的血压控制降低卒中风险 31%[相对风险（RR）0.61，95%置信区间（CI）0.48-0.79]，而 MI 风险的降低则接近但未达到统计学意义[比值比（OR）0.87，95%CI 0.74-1.02]。在一项 meta 回归分析中，SBP 每降低 5mmHg，卒中风险降低 13%（95%CI 5-20，P=0.002），DBP 每降低 2mmHg，卒中风险降低 11.5%（95%CI 5-17，P<0.001）。相比之下，MI 风险与 BP 降低程度无相关性（SBP：P=0.793；DBP：P=0.832）。
在糖尿病患者中，降低 BP 幅度越大，对卒中的保护作用越强。而对于 MI 我们未发现这种相关性。
