Objective

A meta-analysis of the association between metformin prescription and abdominal aortic aneurysm (AAA) growth and events (rupture or surgical repair) was performed.

Methods

Open source databases were searched for observational studies reporting the association between metformin prescription and AAA growth or events. Meta-analyses were performed using random effects models. The risk of bias of included studies was assessed using a quality assessment tool developed in a previous systematic review. Sensitivity analyses restricted to people with diabetes, leave one out analyses, and an individual patient risk factor adjusted sub-analysis were performed. Funnel plots assessed reporting bias.

Results

Eight studies comprising 153 553 patients were included, of whom 35 240 were and 118 313 were not prescribed metformin. Pooled weighted mean (± standard deviation) AAA growth was significantly reduced in patients prescribed metformin (0.9 ± 0.4 mm/year) compared with those not receiving the medication (1.8 ± 0.4 mm/year; weighted mean difference [WMD] 0.8 mm/year, 95% confidence interval [CI] 0.5 – 1.1; p < .001; I² = 89%). Leave one out analysis suggested that the significance of findings did not change after removal of individual studies. A sub-analysis within people with diabetes suggested that metformin reduced AAA growth (WMD 0.7 mm/year, 95% CI 0.3 – 1.0). Metformin prescription was associated with a reduced risk of AAA events (risk ratio 0.6, 95% CI 0.4 – 0.9, p = .028). Three, four, and one studies had low, moderate, and high risk of bias, respectively. Individual patient data analysis suggested that metformin prescription slowed annual AAA growth by 0.5 mm/year (95% CI 0.2 – 0.7). The GRADE summary suggested that the certainty of evidence that metformin limited AAA growth and prevented AAA events was very low.

Conclusion

Observational studies suggest that metformin prescription is associated with a clinically important significant reduction in both growth and clinically relevant events in people with AAA. These findings support the need for randomised trials to examine the benefit of metformin.

中文翻译：

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编辑推荐——二甲双胍处方与腹主动脉瘤生长和临床事件之间的关联：系统评价和荟萃分析

客观的

对二甲双胍处方与腹主动脉瘤 (AAA) 生长和事件（破裂或手术修复）之间的关联进行了荟萃分析。

方法

在开源数据库中搜索报告二甲双胍处方与 AAA 生长或事件之间关联的观察性研究。使用随机效应模型进行荟萃分析。纳入研究的偏倚风险使用先前系统评价中开发的质量评估工具进行评估。进行了仅限于糖尿病患者的敏感性分析、遗漏分析和个体患者风险因素调整后的子分析。漏斗图评估了报告偏倚。

结果

包括 8 项研究，包括 153 553 名患者，其中 35 240 名患者和 118 313 名患者未开具二甲双胍处方。与未接受药物治疗的患者相比（1.8 ± 0.4 毫米/年；加权平均差异 [WMD] 0.8 毫米/年），服用二甲双胍的患者的合并加权平均（± 标准差）AAA 生长显着降低（0.9 ± 0.4 毫米/年） , 95% 置信区间 [CI] 0.5 – 1.1；p < .001；I ²  = 89%）。留一分析表明，在删除个别研究后，结果的重要性没有改变。一项针对糖尿病患者的子分析表明，二甲双胍降低了 AAA 的增长（WMD 0.7 毫米/年，95% CI 0.3 – 1.0）。二甲双胍处方与 AAA 事件风险降低相关（风险比 0.6，95% CI 0.4 – 0.9，p  = .028）。三项、四项和一项研究分别具有低、中和高偏倚风险。个体患者数据分析表明，二甲双胍处方使每年 AAA 的增长减慢了 0.5 毫米/年（95% CI 0.2 – 0.7）。GRADE 总结表明，二甲双胍限制 AAA 生长和预防 AAA 事件的证据质量非常低。

结论

观察性研究表明，二甲双胍处方与 AAA 患者的生长和临床相关事件的临床重要显着减少有关。这些发现支持需要进行随机试验来检验二甲双胍的益处。