Section of Geriatric Cardiology, Department of Cardiovascular Medicine, Azienda Ospedaliero-Universitaria Careggi, Via delle Oblate 4, 50141 Florence, Italy.
Nutr Metab Cardiovasc Dis. 2009 Nov;19(9):604-12. doi: 10.1016/j.numecd.2009.03.021. Epub 2009 May 8.
Randomized clinical trials (RCTs) aimed at the assessment of the efficacy of lowering blood glucose in the prevention of diabetic complications have always failed to detect a significant effect on cardiovascular events. Aim of this meta-analysis is the assessment of the effects of improvement of glycemic control on the incidence of cardiovascular diseases in patients with type 2 diabetes.
The RCTs were included in this meta-analysis if: a) the between-group difference in mean HbA1c during the trial was at least 0.5%, b) they had a planned duration of treatment of at least 3 years, c) if they had a cardiovascular endpoint. Data for analysis were extracted independently by two observers and potential contrasts were resolved by a senior investigator.
Five studies (17,267 and 15,362 patients in the intensive and conventional therapy groups, respectively) were included. Intensive treatment, which reduced mean HbA1c by 0.9% on average, was associated with a significant reduction of incident cardiovascular events and myocardial infarction (OR 0.89 [0.83-0.95] and 0.86 [0.78-0.93], respectively), but not of stroke or cardiovascular mortality (OR 0.93 [0.81-1.07] and 0.98 [0.77-1.23], respectively). In meta-regression analysis, a higher BMI duration of diabetes, and incidence of severe hypoglycaemia were associated with greater risk for cardiovascular death in intensive treatment groups.
Intensified hypoglycaemic treatment in type 2 diabetic patients leads to a significant reduction of the incidence of myocardial infarction, while it does not affect the incidence of stroke and cardiovascular mortality. Hypoglycemia induced by intensified treatment could be associated with increased cardiovascular mortality.
旨在评估降低血糖对预防糖尿病并发症疗效的随机临床试验（RCT）始终未能检测到对心血管事件的显著影响。本荟萃分析的目的是评估改善血糖控制对 2 型糖尿病患者心血管疾病发病率的影响。
如果 RCT 符合以下标准，则将其纳入本荟萃分析：a）试验期间组间平均 HbA1c 差异至少为 0.5%，b）治疗计划持续时间至少 3 年，c）如果有心血管终点。由两名观察者独立提取分析数据，如果存在潜在的差异，由一位资深研究员解决。
纳入了 5 项研究（强化治疗组和常规治疗组分别有 17267 名和 15362 名患者）。强化治疗平均使 HbA1c 降低 0.9%，与心血管事件和心肌梗死发生率的显著降低相关（OR 0.89 [0.83-0.95]和 0.86 [0.78-0.93]），但与卒中或心血管死亡率无关（OR 0.93 [0.81-1.07]和 0.98 [0.77-1.23]）。在荟萃回归分析中，更高的 BMI、糖尿病病程和严重低血糖发生率与强化治疗组心血管死亡风险增加相关。
强化降糖治疗可显著降低 2 型糖尿病患者心肌梗死的发生率，而不影响卒中发生率和心血管死亡率。强化治疗引起的低血糖可能与心血管死亡率增加有关。
