Metformin is associated with favorable outcomes in patients with COVID-19 and type 2 diabetes mellitus

  1. Zhiyuan Ma
  2. Nishit Patel
  3. Pranathi Vemparala
  4. Mahesh Krishnamurthy

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Abstract

Coronavirus disease 2019 (COVID-19) is a new pandemic the entire world is facing since December of 2019. Several risk factors are identified in developing severe disease and one of which is preexisting type 2 diabetes mellitus. Metformin is known to have host-directed anti-viral and anti-inflammatory properties. However, whether these effects offer lower mortality remains unclear. In this retrospective study, we aim to address whether metformin use prior to admission decreases mortality in patients with COVID-19 and pre-existing type 2 diabetes mellitus. A total of 1356 hospitalized patients with COVID-19 and pre-existing type 2 diabetes mellitus was analyzed by multivariable regression. Covariates that potentially confound the association were further adjusted using propensity score matching or inverse probability of treatment weighting. We found that metformin therapy prior to admission in patients with COVID-19 and type 2 diabetes mellitus was significantly associated with less primary outcome events including in-hospital mortality and hospice care enrollment with an odds ratio (OR) of 0.25 (95% CI 0.06–0.74) and less in-hospital length of stay, compared to the non-metformin group. Our results provide supporting evidence that metformin may confer increased survival in patients with COVID-19 and type 2 diabetes mellitus treated with metformin prior to hospitalization.

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  1. Version published to 10.1038/s41598-022-09639-2
  2. ScreenIT

    SciScore for 10.1101/2021.05.20.21257490: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    EthicsIRB: This study was approved by the SLUHN institutional review board
    Consent: SLIR 2020-100) and was granted a waiver of informed consent.
    Sex as a biological variablenot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.

    Table 2: Resources

    No key resources detected.

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    Several limitations are present in our study. First, although efforts were made to balance and control for potential confounding factors by multiple variable adjustments and propensity score matching, due to the inherent nature of retrospective observational studies, residual confounders are likely to exist and could not be balanced. Second, a positive effect was observed in the meta-analysis with an overall reduction of mortality, but the size of the retrospective studies that were included in the meta-analysis varied considerably, resulting in moderate-to-high heterogeneity (I2 = 56%, P=0.04). Future prospective randomized controlled trials are needed to determine any definitive clinical beneficial outcomes in patients with COVID-19 and pre-existing T2DM treated with metformin. In conclusion, our findings demonstrate that metformin therapy prior to admission in patients with COVID-19 and pre-existing T2DM is associated with a significant reduction of in-hospital mortality and provide clinical evidence in support of metformin as first line anti-diabetic agent for patients with COVID-19 and pre-existing T2DM.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    Results from scite Reference Check: We found no unreliable references.

    About SciScore

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  3. Version published to 10.1101/2021.05.20.21257490v1 on medRxiv