Introduction

Diabetes has been linked with poorer outcomes in coronavirus disease (COVID-19) patients. However, the question to whether continue or withdraw metformin therapy in COVID-19 patients with type 2 diabetes mellitus remains contentious. This study aims to investigate the association between metformin and poor COVID-19 outcomes.

Methods

Eligible studies published up to 21 October 2020 were included and appraised for validity, importance, and applicability. The included studies were further ranked according to the level of evidence (LOE).

Results

Nine studies were included for further assessments, of which seven studies stated that metformin was not associated with poor COVID-19 outcomes (LOE II-V), while the other two with poorer designs stated otherwise (LOE V). Although metformin may increase the risk of developing acidosis and lactic acidosis (LOE IV), the observed risks were more accentuated in patients with severe COVID-19 disease or kidney impairment and in patients with > 2 daily metformin doses. Interestingly, one study revealed that metformin may even yield therapeutic role in reducing the risk of COVID-19 mortality (LOE II), although further studies are required to confirm these findings.

Conclusions

Our findings indicated that metformin may be safely continued in COVID-19 patients. The benefit of metformin therapy with simultaneous continuous monitoring of COVID-19 severity and kidney function may outweigh the risks of lactic acidosis, of which incidence is relatively rare.

中文翻译：

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是否需要重新考虑在 COVID-19 2 型糖尿病患者中使用二甲双胍？

介绍

糖尿病与冠状病毒病 (COVID-19) 患者的不良预后有关。然而，对于 COVID-19 2 型糖尿病患者是否继续或停止二甲双胍治疗的问题仍然存在争议。本研究旨在调查二甲双胍与 COVID-19 不良结局之间的关联。

方法

纳入了截至 2020 年 10 月 21 日发表的符合条件的研究，并对其有效性、重要性和适用性进行了评估。纳入的研究根据证据水平（LOE）进一步排序。

结果

九项研究被纳入进一步评估，其中七项研究表明二甲双胍与不良 COVID-19 结果无关（LOE II-V），而另外两项设计较差的研究则另有说明（LOE V）。尽管二甲双胍可能会增加发生酸中毒和乳酸性酸中毒 (LOE IV) 的风险，但观察到的风险在患有严重 COVID-19 疾病或肾功能不全的患者以及每日二甲双胍剂量 > 2 的患者中更为突出。有趣的是，一项研究表明，二甲双胍甚至可能在降低 COVID-19 死亡风险 (LOE II) 方面发挥治疗作用，尽管需要进一步的研究来证实这些发现。

结论

我们的研究结果表明，二甲双胍可以安全地用于 COVID-19 患者。二甲双胍治疗与同时持续监测 COVID-19 严重程度和肾功能的益处可能超过乳酸酸中毒的风险，乳酸酸中毒的发生率相对罕见。