Abstract: Diabetes & Metabolism 46 (2020) 423–426
Available online at
ScienceDirect
www.sciencedirect.com
Mini Review
Metformin and COVID-19: From cellular mechanisms to reduced
mortality
A.J. Scheen
Division of Diabetes, Nutrition and Metabolic Disorders, CHU Liège, and Division of Clinical Pharmacology, Centre for Interdisciplinary Research on Medicines
(CIRM), Liège University, Liège, Belgium
A R T I C L E I N F O
A B S T R A C T
Article history:
Received 8 July 2020
Accepted 12 July 2020
Available online 1 August 2020
Type 2 diabetes mellitus (T2DM) is associated with both poorer clinical outcomes during the COVID-19
pandemic and an increased risk of death in such hospitalized patients. While the role of glucose control
has been emphasized to improve the prognosis, the impact of different glucose-lowering agents remains
largely unknown. Metformin remains the first-line pharmacological choice for the management of
hyperglycaemia in T2DM. Because metformin exerts various effects beyond its glucose-lowering action,
among which are anti-inflammatory effects, it may be speculated that this biguanide might positively
influence the prognosis of patients with T2DM hospitalized for COVID-19. The present concise review
summarizes the available data from observational retrospective studies that have shown a reduction in
mortality in metformin users compared with non-users, and briefly discusses the potential underlying
mechanisms that might perhaps explain this favourable impact. However, given the potential
confounders inherently found in observational studies, caution is required before drawing any firm
conclusions in the absence of randomized controlled trials.
C 2020 Elsevier Masson SAS. All rights reserved.
Keywords:
Inflammation
Meta-analysis
Metformin
Mortality
SARS-CoV-2
Type 2 diabetes
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