Most studies analyze existing use with diabetic patients. Many
results are subject to confounding by indication — metformin is
typically used early in the progression of type 2 diabetes. Prophylaxis
results typically include continuing use after infection and
hospitalization, and greater benefit is seen for more serious outcomes.
The beneficial effect of metformin may be more related to later stages of
COVID-19.
Recent:Cariou Mirani Sourij Oscanoa Kan Petrelli Shaseb.
Submit updates/corrections .
Sep 24 |
Metformin for COVID-19: real-time meta analysis of 75 studies | |
| Statistically significant lower risk is seen for mortality, ventilation, ICU admission, hospitalization, and progression. 47 studies from 44 independent teams in 12 countries show statistically significant improvements. • Meta analysis .. | ||
Aug 30 |
et al., Acta Biomedica Atenei Parmensis, doi:10.23750/abm.v94iS3.14405 | Metformin and Covid-19: a systematic review of systematic reviews with meta-analysis |
| 31% lower mortality (p<0.0001) and 20% lower severe cases (p=0.03). Systematic review and meta analysis of 36 studies showing significantly lower COVID-19 mortality and severity with metformin use. | ||
Aug 24 |
et al., Diabetes, Metabolic Syndrome and Obesity, doi:10.2147/DMSO.S417925 | Effects of Metformin on COVID-19 Patients with Type 2 Diabetes: A Retrospective Study |
| 62% lower combined mortality/intubation (p=0.03) and 81% lower progression (p=0.003). Retrospective 571 type 2 diabetes patients with COVID-19 in China, showing lower combined mortality/mechanical ventilation with metformin. | ||
Aug 18 |
et al., Biomedicines, doi:10.3390/biomedicines11082292 | The Impact of GLP-1 RAs and DPP-4is on Hospitalisation and Mortality in the COVID-19 Era: A Two-Year Observational Study |
| 22% lower hospitalization (p=0.11). Retrospective 76,764 diabetes patients in Italy, showing that patients on metformin had lower rates of COVID-19 hospitalization compared to those on insulin/insulin secretagogues, GLP-1 receptor agonists, and DPP-4 inhibitors. Metformin v.. | ||
Aug 12 |
et al., Frontiers in Endocrinology, doi:10.3389/fendo.2023.1237832 | Clinical characteristics and acute complication of COVID-19 patients with diabetes: a multicenter, retrospective study in Southern China |
| Retrospective 298 hospitalized type 2 diabetes patients in China showing metformin use associated with not having COVID-19, however the analysis considers treatment during hospitalization, and authors note that in this population metformi.. | ||
Jul 13 |
et al., Experimental and Therapeutic Medicine, doi:10.3892/etm.2023.12114 | Anti‑inflammatory effect of metformin against an experimental model of LPS‑induced cytokine storm |
| Mouse study showing that metformin attenuated LPS-induced increases in inflammatory cytokines, demonstrating an anti-inflammatory effect that may be useful against cytokine storm. 60 female mice were pretreated with oral or intraperitonea.. | ||
Jun 24 |
et al., Nutrition, Metabolism and Cardiovascular Diseases, doi:10.1016/j.numecd.2023.06.016 | Association of renin-angiotensin-aldosterone system inhibitors with best COVID-19 outcomes in a diabetic population of the Veneto Region (north-east Italy): a lesson for endemic phase? |
| 53% lower combined mortality/ICU admission (p=0.08) and 45% lower hospitalization (p=0.0002). Retrospective diabetic COVID-19 patients in Italy, showing lower risk of hospitalization with metformin use. | ||
Jun 8 |
et al., Endocrine Practice, doi:10.1016/j.eprac.2023.06.001 | Association of metformin, dipeptidyl dipeptidase-4 inhibitors, and insulin with COVID-19-related hospital outcomes in patients with type 2 diabetes |
| 1% higher mortality (p=0.98), 4% higher ventilation (p=0.87), and 8% lower ICU admission (p=0.72). Retrospective 529 hospitalized COVID-19 patients with type 2 diabetes, showing no significant difference in outcomes with metformin use. This does not account for the different risk of being hospitalized based on metformin use. Authors no.. | ||
Jun 6 |
et al., Obesity and metabolism, doi:10.14341/omet12801 | Factors influencing the severity of COVID-19 course for patients with diabetes mellitus in tashkent: a retrospective cohort study |
| 15% lower hospitalization (p=0.56). Retrospective 763 COVID-19 patients with type 2 diabetes in Uzbekistan, showing lower hospitalization with metformin use in unadjusted results, without statistical significance. | ||
May 19 |
et al., Free Radical Biology and Medicine, doi:10.1016/j.freeradbiomed.2023.03.245 | Enhanced fatty acid oxidation through Metformin and Baicalin as therapy for COVID-19 and associated inflammatory states in lung and kidney |
| Retrospective study showing shorter ICU stay with metformin, animal study showing that metformin minimized lung damage in an ARDS model, and in vitro study showing increased mitochondrial function and decreased TGF-β-induced fibrosis, apo.. | ||
May 19 |
et al., medRxiv, doi:10.1101/2023.05.19.23290214 | Effects of antidiabetic drugs on mortality risks in individuals with type 2 diabetes: A prospective cohort study of UK Biobank participants |
| 60% lower mortality (p<0.0001). UK Biobank retrospective including 43,610 type 2 diabetes patients, showing lower mortality with metformin use within matched type 2 diabetes patients. | ||
May 19 |
et al., Diabetologia, doi:10.1007/s00125-023-05928-1 | Risk phenotypes of diabetes and association with COVID-19 severity and death: an update of a living systematic review and meta-analysis |
| 31% lower mortality (p<0.0001) and 22% lower severe cases (p<0.0001). Systematic review and meta analysis showing significantly lower COVID-19 mortality and severity with metformin use. Authors analyze 169 studies of diabetes patients, with 23 reporting mortality results and 34 reporting severity results fo.. | ||
May 15 |
et al., Biomedicine & Pharmacotherapy, doi:10.1016/j.biopha.2023.114892 | The F/B ratio as a biomarker for inflammation in COVID-19 and T2D: Impact of metformin |
| Analysis of 115 pateints in Ukraine, providing evidence that the gut microbiome may play a role in the inflammatory response of COVID-19 patients, that the firmicutes/bacteroidetes ratio may be a potential biomarker for inflammation, and .. | ||
May 6 |
et al., Diabetes Research and Clinical Practice, doi:10.1016/j.diabres.2023.110692 | Metformin use before COVID-19 vaccination and the risks of COVID-19 incidence, medical utilization, and all-cause mortality in patients with type 2 diabetes mellitus |
| 25% lower mortality (p=0.001), 25% lower ventilation (p=0.01), 19% lower ICU admission (p=0.005), and 15% lower hospitalization (p<0.0001). TriNetX retrospective 123,709 vaccinated patients with type 2 diabetes, showing significantly lower risk of COVID-19 mortality, mechanical ventilation, and hospitalization with metformin use. There was no significant difference for cases... | ||
Mar 31 |
et al., PLOS ONE, doi:10.1371/journal.pone.0282961 | Outpatient medications associated with protection from COVID-19 hospitalization |
| 3% lower hospitalization (p=0.004). Retrospective 3,974,272 COVID-19 patients in the USA, showing 3% lower risk of hospitalization with pre-existing metformin use. | ||
Feb 23 |
et al., PLOS ONE, doi:10.1371/journal.pone.0282210 | Is metformin use associated with low mortality in patients with type 2 diabetes mellitus hospitalized for COVID-19? a multivariable and propensity score-adjusted meta-analysis |
| Meta analysis of 22 metformin studies, showing significantly lower mortality with metformin use prior to hospitalization. | ||
Jan 31 |
et al., Annals of the National Academy of Medical Sciences (India), doi:10.1055/s-0042-1760353 | Association of Metformin with Mortality in COVID-19 Patients: A Systematic Review and Meta-Analysis |
| 37% lower mortality (p<0.0001). Systematic review and meta analysis showing significantly lower mortality with metformin. | ||
Jan 20 |
et al., Medicine, doi:10.1097/md.0000000000032650 | Blood glucose control with different treatment regimens in type 2 diabetes patients hospitalized with COVID-19 infection: A retrospective study |
| 45% lower mortality (p=0.0001) and 7% shorter hospitalization (p=0.5). Retrospective 359 COVID-19 patients with diabetes in Israel, showing lower mortality in the other treatments group compared to the insulin group, with 80% of the other treatments group receiving metformin. Groups refer to use during hospi.. | ||
Jan 6 |
et al., Microorganisms, doi:10.3390/microorganisms11010145 | Diabetes and SARS-CoV-2 Infection: The Potential Role of Antidiabetic Therapy in the Evolution of COVID-19 |
| 15% lower severe cases (p=0.05). Retrospective 43 diabetes patients hospitalized for COVID-19 in Italy, showing lower risk of severe cases with metformin vs. insulin. | ||
Dec 31 2022 |
et al., Current Research in Medical Sciences, doi:10.22088/crms.6.2.32 | Comparison of clinical and laboratory parameters of COVID-19 in diabetic patients using different glucose-lowering drugs: a retrospective study |
| Retrospective 157 diabetic patients in Iran reporting shorter hospitalization with metformin, however numbers in this paper are inconsistent. The counts and percentages for death in Table 1 are not possible - 11 (13.92%) for metformin cou.. | ||
Dec 24 2022 |
et al., The Lancet Infectious Diseases, doi:10.1016/S1473-3099(23)00299-2 | Outpatient treatment of COVID-19 and incidence of post-COVID-19 condition over 10 months (COVID-OUT): a multicentre, randomised, quadruple-blind, parallel-group, phase 3 trial |
| 41% lower PASC (p=0.01). Long-term 10 month followup for NCT04510194, showing significantly lower incidence of PASC with metformin treatment. Adjusted results are provided for metformin but not for ivermectin or fluvoxamine. For many issues with this trial, see [.. | ||
Dec 7 2022 |
et al., Annals of Endocrinology, doi:10.1016/j.ando.2023.08.002 | Mortality-related risk factors of inpatients with diabetes and COVID-19: a multicenter retrospective study in Belgium |
| 49% lower mortality (p=0.002). Retrospective 375 hospitalized diabetes patients in Belgium, showing lower risk of COVID-19 mortality with metformin use. | ||
Nov 9 2022 |
et al., Frontiers in Endocrinology, doi:10.3389/fendo.2022.1002834 | Metformin use and mortality and length of stay among hospitalized patients with type 2 diabetes and COVID-19: A multiracial, multiethnic, urban observational study |
| 1% lower mortality (p=0.91) and 5% shorter hospitalization (p=0.23). Retrospective 4,462 COVID+ diabetes patients in the USA, showing no significant difference in outcomes with metformin use. | ||
Nov 9 2022 |
et al., Journal of Community Hospital Internal Medicine Perspectives, doi:10.55729/2000-9666.1127 | Evaluation of Glycemic Control and Predictors of Severe Illness and Death in Patients With Diabetes Hospitalized With COVID-19 |
| 33% lower severe cases (p=0.03). Retrospective 733 hospitalized COVID-19 patients with diabetes in the USA, showing lower risk of severity with metformin use. | ||
Oct 31 2022 |
et al., Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy, doi:10.2147/DMSO.S385646 | Infection Rates and Impact of Glucose Lowering Medications on the Clinical Course of COVID-19 in People with Type 2 Diabetes: A Retrospective Observational Study |
| 38% lower mortality (p=0.02) and 15% lower hospitalization (p=0.25). Retrospective 54,009 diabetes patients in Italy, showing lower mortality with metformin use. | ||
Oct 10 2022 |
et al., PLOS ONE, doi:10.1371/journal.pone.0275787 | COVID-19 outcomes in patients taking cardioprotective medications |
| 41% lower mortality (p=0.003), 16% higher ventilation (p=0.49), 3% lower ICU admission (p=0.85), and 4% higher hospitalization (p=0.72). Retrospective 13,585 COVID+ patients in the USA, showing lower mortality with metformin use, but no significant difference for ventilation, ICU admission, and hospitalization. | ||
Oct 4 2022 |
et al., Primary Care Diabetes, doi:10.1016/j.pcd.2022.10.001 | Antidiabetic treatment and COVID-19 Outcomes: A population-based cohort study in primary health care in Catalonia during the first wave of the pandemic |
| 10% lower mortality (p=0.19) and 8% lower combined mortality/hospitalization (p=0.12). Retrospective 31,006 diabetic COVID-19 patients in Spain, showing lower mortality with metformin treatment, without statistical significance. Authors provide results for metformin compared with untreated patients rather than all non-metfo.. | ||
Oct 1 2022 |
et al., Medical Archives, doi:10.5455/medarh.2022.76.329-332 | Effects of Metformin, Insulin on Hematological Parameters of COVID-19 Patients with Type 2 Diabetes |
| Analysis of hematologic parameters in COVID-19 patients with diabetes in Ukraine, showing significantly lower CRP for patients taking metformin. | ||
Sep 21 2022 |
et al., SSRN Electronic Journal, doi:10.2139/ssrn.4225660 | Metformin Does Not Reduce Hospitalisation for COVID-19 |
| 7% lower combined mortality/hospitalization (p=0.61) and 15% lower progression (p=0.16). Retrospective 12,331 diabetes patients in Hong Kong, showing no significant difference in outcomes with metformin use. | ||
Sep 13 2022 |
et al., Diabetes, Obesity and Metabolism, doi:10.1111/dom.14872 | Ethnicity and risks of severe COVID-19 outcomes associated with glucose-lowering medications: A cohort study |
| 34% lower mortality (p<0.0001) and 31% lower hospitalization (p<0.0001). Retrospective 624,771 people with type 2 diabetes in the UK, showing lower COVID-19 mortality and hospitalization with metformin use. | ||
Aug 30 2022 |
et al., medRxiv, doi:10.1101/2022.08.29.22279355 | Metformin is Associated with Reduced COVID-19 Severity in Patients with Prediabetes |
| 59% lower mortality (p=0.66), 54% lower severe cases (p=0.37), and 42% lower progression (p=0.37). Retrospective 3,136 patients with prediabetes and 282 with PCOS, showing metformin associated with reduced COVID-19 severity. | ||
Aug 18 2022 |
et al., NEJM, doi:10.1056/NEJMoa2201662 | Randomized Trial of Metformin, Ivermectin, and Fluvoxamine for Covid-19 |
| 52% lower combined mortality/hospitalization (p=0.09) and 40% lower progression (p=0.03). COVID-OUT remotely operated RCT, showing lower combined ER/hospitalization/death with metformin. Results for other treatments are listed separately - ivermectin , fluvoxamine . The "control" group includes patients receiving active treatm.. | ||
Aug 16 2022 |
et al., medRxiv, doi:10.1101/2022.08.14.22278751 | Real-world evidence with a retrospective cohort of 15,968 Andalusian COVID-19 hospitalized patients suggests 21 new effective treatments and one drug that increases death risk |
| 30% lower mortality (p<0.0001). Retrospective 15,968 COVID-19 hospitalized patients in Spain, showing lower mortality with existing use of several medications including metformin, HCQ, aspirin, vitamin D, vitamin C, and budesonide. | ||
Aug 9 2022 |
et al., Frontiers in Endocrinology, doi:10.3389/fendo.2022.909874 | Risk factors for COVID-19 case fatality rate in people with type 1 and type 2 diabetes mellitus: A nationwide retrospective cohort study of 235,248 patients in the Russian Federation |
| 22% lower mortality (p=0.001). Retrospective 224,190 type 2 diabetes patients in Russia, showing lower mortality with metformin use. | ||
Jul 6 2022 |
et al., Cell Reports Methods, doi:10.1016/j.crmeth.2023.100503 (date from preprint) | Integrative analysis of functional genomic screening and clinical data identifies a protective role for spironolactone in severe COVID-19 |
| 50% lower ventilation (p=0.01) and 51% lower ICU admission (p<0.0001). PSM retrospective 64,349 COVID-19 patients in the USA, showing metformin associated with lower ICU admission and mechanical ventilation. | ||
Jul 2 2022 |
et al., Advanced Pharmaceutical Bulletin, doi:10.34172/apb.2023.066 | Long and Short-term Metformin Consumption as a Potential Therapy to Prevent Complications of COVID-19 |
| 74% lower mortality (p=0.06), 79% lower ventilation (p=0.05), 63% lower ICU admission (p=0.07), and 5% shorter hospitalization (p=0.52). RCT 189 hospitalized patients showing lower mortality, ICU admission, and intubation with metformin, statistically significant only for intubation. Treatment patients may have also taken metformin prior to admission. Authors note that pat.. | ||
Jun 29 2022 |
et al., Journal of General Internal Medicine, doi:10.1007/s11606-022-07701-3 | Medications Associated with Lower Mortality in a SARS-CoV-2 Positive Cohort of 26,508 Veterans |
| 67% lower mortality (p<0.0001). Retrospective 26,508 consecutive COVID+ veterans in the USA, showing lower mortality with multiple treatments including metformin. Treatment was defined as drugs administered ≥50% of the time within 2 weeks post-COVID+, and may be a cont.. | ||
Jun 9 2022 |
et al., BMJ Open Diabetes Research & Care, doi:10.1136/bmjdrc-2022-002774 | Hospitalization and mortality in patients with COVID-19 with or at risk of type 2 diabetes: data from five health systems in Pennsylvania and Maryland |
| 44% lower progression (p<0.0001) and 37% lower hospitalization (p<0.0001). Retrospective 4,944 COVID-19 patients with type 2 diabetes in the USA, showing lower risk of hospitalization and combined ICU/intubation/death with metformin use. | ||
Apr 1 2022 |
et al., Scientific Reports, doi:10.1038/s41598-022-09639-2 | Metformin is associated with favorable outcomes in patients with COVID-19 and type 2 diabetes mellitus |
| 74% lower mortality (p=0.03) and 25% lower ventilation (p=0.44). PSM/IPTW retrospective 1,356 hospitalized COVID-19 patients with type 2 diabetes in China, showing lower mortality/hospice with metformin use. | ||
Mar 29 2022 |
et al., Open Forum Infectious Diseases, doi:10.1093/ofid/ofac156 | Screening Large Population Health Databases for Potential COVID-19 Therapeutics: A Pharmacopeia-Wide Association Study (PWAS) of Commonly Prescribed Medications |
| 1% fewer cases (p=0.45). Retrospective 26,121 cases and 2,369,020 controls ≥65yo in Canada, showing no significant difference in cases with chronic use of metformin. | ||
Mar 7 2022 |
et al., Frontiers in Endocrinology, doi:10.3389/fendo.2022.810914 | Metformin Use in Relation to Clinical Outcomes and Hyperinflammatory Syndrome Among COVID-19 Patients With Type 2 Diabetes: A Propensity Score Analysis of a Territory-Wide Cohort |
| 59% lower mortality (p=0.01), 61% improved recovery (p=0.005), 64% greater improvement (p=0.009), and 56% higher hospital discharge (p=0.009). Retrospective 1,214 COVID+ type 2 diabetes patients in Hong Kong, showing lower mortality and improved recovery with metformin use. | ||
Feb 24 2022 |
et al., Diabetes Care, doi:10.2337/dc21-2186 | Glycemic Control and Clinical Outcomes in U.S. Patients With COVID-19: Data From the National COVID Cohort Collaborative (N3C) Database |
| 51% lower mortality (p<0.0001), 41% lower ventilation (p<0.0001), and 40% lower hospitalization (p<0.0001). N3C retrospective 39,616 COVID-19 patients with diabetes in the USA, showing lower mortality, ventilation, and hospitalization with metformin use. | ||
Jan 18 2022 |
et al., Journal of Thrombosis and Thrombolysis, doi:10.1007/s11239-022-02631-7 | Metformin use in patients hospitalized with COVID-19: lower inflammation, oxidative stress, and thrombotic risk markers and better clinical outcomes |
| 60% lower mortality (p=0.21), 76% lower ventilation (p=0.05), and 34% shorter hospitalization (p=0.13). Retrospective 75 diabetes patients, 34 on metformin, showing improved clinical outcomes with treatment, without statistical significance. | ||
Jan 17 2022 |
et al., International Journal of Endocrinology, doi:10.1155/2022/9322332 | Prognostic Factors for COVID-19 Hospitalized Patients with Preexisting Type 2 Diabetes |
| 72% improved recovery (p=0.03). Retrospective 108 T2D patients hospitalized with COVID-19, showing lower risk of unfavorable outcomes with metformin use vs. other diabetic medications. | ||
Jan 10 2022 |
et al., Diabetes, Obesity and Metabolism, doi:10.1111/dom.14648 | Metformin use is associated with a decrease in risk of hospitalization and mortality in COVID-19 diabetic patients: a population-based study in Lombardy |
| 16% lower mortality (p<0.0001), 22% lower ICU admission (p=0.01), and 3% lower hospitalization (p=0.11). Retrospective 31,966 COVID+ patients using anti-hyperglycemic drugs in Italy, showing lower mortality and ICU admission with metformin use. | ||
Dec 31 2021 |
et al., BMJ Open, doi:10.1136/bmjopen-2021-050051 | Association of the patterns of use of medications with mortality of COVID-19 infection: a hospital-based observational study |
| 72% lower mortality (p<0.0001). Retrospective 9,532 hospitalized COVID+ veterans in the USA, showing lower mortality with metformin use. The study provides results for use before, after, and before+after. Before+after should more accurately represent prophylaxis up to C.. | ||
Nov 30 2021 |
et al., Diabetes & Metabolism, doi:10.1016/j.diabet.2021.101297 | The association between metformin treatment and COVID-19 outcomes according to metformin continuation during hospitalisation |
| 55% lower combined mortality/ICU admission (p=0.04). Retrospective 140 diabetic patients in France, showing lower mortality for patients where metformin use was continued after hospitalization. | ||
Nov 19 2021 |
et al., bioRxiv, doi:10.1101/2021.11.18.469078 | Metformin Suppresses SARS-CoV-2 in Cell Culture |
| In Vitro study showing metformin inhibits SARS-CoV-2 in Caco2 cells. Metformin reduced viral titers by nearly 99%, and by about 90% when cells were treated prior to infection. | ||
Nov 8 2021 |
et al., Circulation, 144:A12228 | Metformin Use in Patients Hospitalized With COVID-19: Lower Inflammation, Oxidative Stress, and Thrombotic Risk Markers and Better Clinical Outcomes |
| 60% lower mortality (p=0.21) and 76% lower ventilation (p=0.05). Retrospective 75 diabetes patients, 34 on metformin, showing lower mortality with treatment in unadjusted results with minimal group details. | ||
Oct 30 2021 |
et al., Journal of the ASEAN Federation of Endocrine Societies, doi:10.15605/jafes.036.02.20 | Association Between Metformin Use and Mortality Among Patients with Type 2 Diabetes Mellitus Hospitalized for COVID-19 Infection |
| 47% lower mortality (p=0.02). Retrospective 355 diabetic hospitalized COVID-19 patients in the Philippines, showing lower mortality with metformin use. | ||
Oct 29 2021 |
et al., Irish Journal of Medical Science, doi:10.1007/s11845-021-02823-9 | Preadmission usage of metformin and mortality in COVID-19 patients including the post-discharge period |
| 42% lower mortality (p=0.02). Retrospective 586 diabetic hospitalized COVID-19 patients in Turkey, showing lower mortality with existing metformin use. | ||
Oct 6 2021 |
et al., Diabetes Care, doi:10.2337/dc21-1351 | Prior Glucose-Lowering Medication Use and 30-Day Outcomes Among 64,892 Veterans With Diabetes and COVID-19 |
| 15% lower mortality (p<0.0001), 2% lower ICU admission (p=0.62), and 3% lower hospitalization (p=0.09). Retrospective 64,892 veterans with diabetes in the USA, showing lower mortality with existing metformin use. | ||
Sep 29 2021 |
et al., Endocrinology, Diabetes & Metabolism, doi:10.1002/edm2.301 | Inpatient use of metformin and acarbose is associated with reduced mortality of COVID-19 patients with type 2 diabetes mellitus |
| 76% lower mortality (p=0.02). Retrospective 131 hospitalized COVID-19 patients with type 2 diabetes, showing lower mortality with metformin treatment and acarbose treatment. | ||
Sep 16 2021 |
et al., Frontiers in Endocrinology, doi:10.3389/fendo.2021.708494 | Mortality Risk of Antidiabetic Agents for Type 2 Diabetes With COVID-19: A Systematic Review and Meta-Analysis |
| 31% lower mortality (p=0.001). Meta analysis of 14 studies showing significantly lower COVID-19 mortality with metformin use. | ||
Sep 9 2021 |
et al., Scientific Reports, doi:10.1038/s41598-021-96720-x | Impact of overlapping risks of type 2 diabetes and obesity on coronavirus disease severity in the United States |
| 39% lower hospitalization (p=0.04). Retrospective 28,093 COVID+ patients in the USA, showing lower risk of hospitalization with metformin use. | ||
Sep 7 2021 |
et al., BMJ Open Diabetes Research & Care, doi:10.1136/bmjdrc-2021-002299 | Evaluation and management of COVID-19-related severity in people with type 2 diabetes |
| 12% lower ICU admission (p=0.005). Retrospective 16,504 COVID-19 type 2 diabetes patients, showing lower risk of ICU admission with existing metformin use. | ||
Aug 31 2021 |
et al., Diabetes Research and Clinical Practice, doi:10.1016/j.diabres.2021.108977 | The effect of metformin on mortality and severity in COVID-19 patients with diabetes mellitus |
| 36% lower mortality (p<0.0001). Meta analysis of 17 studies including 20,719 COVID-19 patients with diabetes, showing lower risk of mortality and severity with metformin. | ||
Aug 31 2021 |
et al., The Lancet Regional Health - Americas, doi:10.1016/j.lana.2021.100142 (date from preprint) | Effect of early treatment with metformin on risk of emergency care and hospitalization among patients with COVID-19: The TOGETHER randomized platform clinical trial |
| 27% lower mortality (p=0.53), 6% lower hospitalization (p=0.88), 14% more combined hospitalization/ER visits (p=0.58), and 31% lower progression (p=0.48). Data for the primary outcome in this trial appears to be impossible [doyourownresearch.substack.com]. For example, considering the metformin arm and the ITT population: 24 were hospitalized and 8 had an ER visit (tables S2/S3), therefore .. | ||
Aug 20 2021 |
et al., Cell Metabolism, doi:10.1016/j.cmet.2020.08.013 | Metformin Is Associated with Higher Incidence of Acidosis, but Not Mortality, in Individuals with COVID-19 and Pre-existing Type 2 Diabetes |
| 65% higher mortality (p=0.25). Retrospective 1,213 hospitalized diabetic COVID-19 patients in China, showing no significant difference in mortality with pre-existing metformin use. | ||
Aug 19 2021 |
et al., Frontiers in Medicine, doi:10.3389/fmed.2021.704666 | Metformin in Patients With COVID-19: A Systematic Review and Meta-Analysis |
| 34% lower mortality (p<0.0001). Meta analysis of 19 studies showing metformin use associated with lower COVID-19 mortality and hospitalization. | ||
Jul 18 2021 |
et al., Diabetes Therapy, doi:10.1007/s13300-021-01110-1 | Risk Factors Associated with COVID-19 Hospitalization and Mortality: A Large Claims-Based Analysis Among People with Type 2 Diabetes Mellitus in the United States |
| 10% lower hospitalization (p<0.0001). Retrospective 9531 COVID+ diabetes patients in the USA, showing lower risk of hospitalization with existing biguanides treatment (defined as mainly metformin in the abstract and entirely metformin in the text). | ||
Jul 17 2021 |
et al., GeroScience, doi:10.1007/s11357-021-00397-z | Therapeutic prevention of COVID-19 in elderly: a case–control study |
| 79% lower mortality (p=0.06) and 44% more cases (p=0.12). Retrospective 179 patients in France exposed to COVID-19 showing, without statistical significance, a higher risk of cases, and a lower risk of mortality among cases with existing metformin treatment. | ||
Jul 13 2021 |
et al., Diabetology & Metabolic Syndrome, doi:10.1186/s13098-021-00695-8 | Outcome and death risk of diabetes patients with Covid-19 receiving pre-hospital and in-hospital metformin therapies |
| 97% lower mortality (p=0.02). Retrospective 188 hospitalized patients in Brazil, showing lower risk of mortality with metformin use. Authors note that, although pre-hospital metformin use improved clinical parameters at admission, continuous use during hospitalization.. | ||
May 24 2021 |
et al., Clinical Diabetology, doi:10.5603/DK.a2021.0035 | Metformin therapy and severity and mortality of SARS-CoV-2 infection: a meta-analysis |
| 44% lower mortality (p<0.0001) and 15% lower severe cases (p=0.08). Meta analysis of 32 studies showing significantly lower COVID-19 mortality with metformin use. | ||
May 5 2021 |
et al., medRxiv, doi:10.1101/2021.04.20.21255792 | Retrospective Assessment of Treatments of Hospitalized Covid-19 Patients |
| 30% lower mortality (p=0.42). Retrospective 1,035 hospitalized patients in India. Of 366 diabetic patients, there was lower mortality for the 53 that were on metformin. | ||
Apr 14 2021 |
et al., Gerontology, doi:10.1159/000515159 | COVID-19: Clinical Presentation and Prognostic Factors of Severe Disease and Mortality in the Oldest-Old Population: A Cohort Study |
| 16% higher mortality (p=0.46) and 16% higher severe cases (p=0.46). Analysis of 103 elderly hospitalized COVID-19 patients in Spain, showing higher mortality with metformin, without statistical significance. | ||
Apr 6 2021 |
et al., medRxiv, doi:10.1101/2021.03.22.21254110 | Drug repositioning candidates identified using in-silico quasi-quantum molecular simulation demonstrate reduced COVID-19 mortality in 1.5M patient records |
| 27% lower mortality (p<0.0001). In Silico study followed by PSM analysis of the National COVID Cohort Collaborative data in the USA, showing 27% lower mortality with metformin use. | ||
Mar 31 2021 |
et al., Diabetes & Metabolic Syndrome: Clinical Research & Reviews, doi:10.1016/j.dsx.2021.02.022 | Metformin is associated with lower hospitalizations, mortality and severe coronavirus infection among elderly medicare minority patients in 8 states in USA |
| 66% lower mortality (p=0.0002), 29% lower hospitalization (p=0.008), and 68% lower ARDS (p<0.0001). Retrospective 1,139 elderly COVID+ patients in the USA, 392 with pre-existing metformin use, showing significantly lower mortality, hospitalization, and ARDS with treatment. | ||
Mar 31 2021 |
et al., Diabetes Research and Clinical Practice, doi:10.1016/j.diabres.2020.108619 | Association of metformin with mortality or ARDS in patients with COVID-19 and type 2 diabetes: A retrospective cohort study |
| 46% lower mortality (p=0.4) and 80% lower progression (p=0.02). Retrospective 328 COVID-19 patients with type 2 diabetes in China, showing significantly lower risk of ARDS with existing metformin use. | ||
Mar 30 2021 |
et al., The Lacent Diabetes & Endocrinology, doi:10.1016/S2213-8587(21)00050-4 | Prescription of glucose-lowering therapies and risk of COVID-19 mortality in people with type 2 diabetes: a nationwide observational study in England |
| 23% lower mortality (p<0.0001). Retrospective 2,851,465 people with type 2 diabetes in the UK, showing lower mortality with existing metformin use. Results are subject to confounding by indication because metformin is typically used early in the progression of type 2 di.. | ||
Mar 30 2021 |
et al., Thorax, doi:10.1136/thoraxjnl-2021-217487 | Risk factors for developing COVID-19: a population-based longitudinal study (COVIDENCE UK) |
| 27% more cases (p=0.42). Prospective survey-based study with 15,227 people in the UK, showing lower risk of COVID-19 cases with vitamin A, vitamin D, zinc, selenium, probiotics, and inhaled corticosteroids; and higher risk with metformin and vitamin C. Statistica.. | ||
Mar 23 2021 |
et al., Journal of Medical Virology, doi:10.1002/jmv.26873 | Outpatient metformin use is associated with reduced severity of COVID‐19 disease in adults with overweight or obesity |
| 62% lower mortality (p=0.03), 9% higher ICU admission (p=0.78), and 22% lower hospitalization (p=0.1). Retrospective 17,396 PCR+ patients in the USA, showing lower mortality with metformin use. | ||
Feb 17 2021 |
et al., Diabetologia, doi:10.1007/s00125-020-05351-w | Predictors of hospital discharge and mortality in patients with diabetes and COVID-19: updated results from the nationwide CORONADO study |
| 28% lower mortality (p=0.03) and 15% higher hospital discharge (p=0.02). Retrospective 2,796 hospitalized diabetes patients with COVID-19 in France, showing lower mortality with metformin use. | ||
Feb 13 2021 |
et al., Acta Diabetologica, doi:10.1007/s00592-020-01666-7 | Metformin use and risk of COVID-19 among patients with type II diabetes mellitus: an NHIS-COVID-19 database cohort study |
| 26% higher mortality (p=0.3) and 28% fewer cases (p<0.0001). Retrospective 27,493 type II diabetes patients in the USA, 7,204 on metformin, showing significantly lower COVID-19 cases, but no significant difference in mortality. | ||
Jan 31 2021 |
et al., Journal of the American Medical Directors Association, doi:10.1016/j.jamda.2020.10.031 | Metformin is Associated with Decreased 30-Day Mortality Among Nursing Home Residents Infected with SARS-CoV2 |
| 52% lower mortality (p=0.009). Retrospective 775 nursing home residents in the USA, showing lower mortality with existing metformin use. | ||
Jan 13 2021 |
et al., Front. Endocrinol., doi:10.3389/fendo.2020.600439 | Metformin Use Is Associated With Reduced Mortality in a Diverse Population With COVID-19 and Diabetes |
| 61% lower mortality (p=0.02). Retrospective 219 COVID-19+ diabetes patients in the USA, showing lower mortality with existing metformin treatment. | ||
Dec 28 2020 |
et al., Research Square, doi:10.21203/rs.3.rs-133358/v1 | Association between prior cardiometabolic therapy and in-hospital mortality in very old patients with type 2 diabetes mellitus hospitalized due to COVID-19. A nationwide observational study in Spain |
| 1% lower mortality (p=0.78). Retrospective 790 hospitalized type 2 diabetes patients ≥80 years old in Spain, showing no significant difference in mortality with existing metformin use. | ||
Dec 19 2020 |
et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2020.12.041 | Association of prescribed medications with the risk of COVID-19 infection and severity among adults in South Korea |
| 1% higher progression (p=0.11) and 4% fewer cases (p=0.82). Retrospective database analysis showing no significant differences with pre-existing metformin use. | ||
Dec 10 2020 |
et al., Diabetes & Metabolism, doi:10.1016/j.diabet.2020.101216 | Metformin use is associated with a reduced risk of mortality in patients with diabetes hospitalised for COVID-19 |
| 22% lower mortality (p=0.16), 18% lower combined mortality/intubation (p=0.21), and 7% lower ventilation (p=0.72). Retrospective 2,449 hospitalized COVID-19 diabetes patients in France, 1,496 with existing metformin use, showing lower mortality with treatment. Statistical significance was reached in model 1 but not in models 2-4 which also adjust for .. | ||
Dec 4 2020 |
et al., Diabetes, Obesity and Metabolism, doi:10.1111/dom.14256 | COVID‐19 fatality prediction in people with diabetes and prediabetes using a simple score upon hospital admission |
| 37% lower mortality (p=0.13). Retrospective 247 hospitalized COVID-19 diabetes patients, showing lower mortality with metformin use in unadjusted results. | ||
Dec 3 2020 |
et al., The Lancet Healthy Longevity, doi:10.1016/S2666-7568(20)30033-7 | Metformin and risk of mortality in patients hospitalised with COVID-19: a retrospective cohort analysis |
| 12% lower mortality (p=0.65). Retrospective 6,256 COVID-19+ diabetes patients in the USA, showing lower mortality with existing metformin treatment, statistically significant only for women. | ||
Nov 17 2020 |
et al., PLOS ONE, doi:10.1371/journal.pone.0241264 | Clinical, regional, and genetic characteristics of Covid-19 patients from UK Biobank |
| 30% more cases (p=0.08). 397,064 patient UK Biobank retrospective showing higher risk of COVID-19 with metformin use, without statistical significance. Metformin is typically prescribed for diabetes, diabetes patients have significantly higher COVID-19 risk, and .. | ||
Nov 16 2020 |
et al., BMC Medicine, doi:10.1186/s12916-020-01832-2 | Mortality and other adverse outcomes in patients with type 2 diabetes mellitus admitted for COVID-19 in association with glucose-lowering drugs: a nationwide cohort study |
| 10% higher mortality (p=0.48). Retrospective 2,666 type 2 diabetes COVID-19 patients in Spain, showing higher mortality with existing metformin use (not statistically significant). | ||
Nov 11 2020 |
et al., Diabetes & Metabolic Syndrome: Clinical Research & Reviews, doi:10.1016/j.dsx.2020.11.006 | The Effect of Metformin Consumption on Mortality in Hospitalized COVID-19 patients: a systematic review and meta-analysis |
| 36% lower mortality (p=0.03). Meta analysis of 9 studies showing lower mortality with metformin use. | ||
Oct 19 2020 |
et al., Clinical and Translational Science, doi:10.1111/cts.12897 | Risk of Metformin in Patients With Type 2 Diabetes With COVID-19: A Preliminary Retrospective Report |
| 225% higher progression (p=0.05). Retrospective 110 hospitalized COVID-19 patients with diabetes in China, showing increased risk of severity with metformin. | ||
Oct 13 2020 |
et al., Epidemiology and Infection, doi:10.1017/S0950268820002472 | Risk factors for severe disease in patients admitted with COVID-19 to a hospital in London, England: a retrospective cohort study |
| 3% lower mortality (p=0.81). Retrospective 981 hospitalized patients in the UK, showing no significant difference with metformin use. | ||
Oct 6 2020 |
et al., Diabetes Care, doi:10.2337/dc20-1340 | Impact of Comorbidities and Glycemia at Admission and Dipeptidyl Peptidase 4 Inhibitors in Patients With Type 2 Diabetes With COVID-19: A Case Series From an Academic Hospital in Lombardy, Italy |
| 45% lower mortality (p=0.1). Retrospective 90 hospitalized COVID-19 patients with diabetes in Italy, showing lower mortality with metformin use, without statistical significance. | ||
Oct 1 2020 |
et al., Endocrine Practice, doi:10.4158/EP-2020-0466 | Metformin Use in Diabetes Prior to Hospitalization: Effects on Mortality in Covid-19 |
| 78% lower mortality (p=0.02). Retrospective 131 type II diabetes patients with COVID pneumonia, showing lower mortality with existing metformin use. Acarbose (commonly used in China as an initial therapy for diabetes) did not have a similar association with mortality,.. | ||
Sep 30 2020 |
et al., Journal of Medical Virology, doi:10.1002/jmv.26498 | Mortality risk with preadmission metformin use in patients with COVID-19 and diabetes: A meta-analysis |
| Meta analysis of 5 studies showing lower mortality with metformin use. | ||
Aug 23 2020 |
et al., medRxiv, doi:10.1101/2020.08.20.20174169 | Associations of comorbidities and medications with COVID-19 outcome: A retrospective analysis of real-world evidence data |
| 65% lower mortality (p=0.04). Retrospective diabetes patients in the UK, showing lower mortality for metformin treatment (administered within 21 days after a positive PCR test). | ||
Aug 18 2020 |
et al., Obesity Medicine, doi:10.1016/j.obmed.2020.100290 | Metformin use is associated with reduced mortality rate from coronavirus disease 2019 (COVID-19) infection |
| Meta analysis of 5 studies showing lower mortality with metformin use. | ||
Aug 12 2020 |
et al., Diabetes & Metabolism Journal, doi:10.4093/dmj.2020.0146 | The Clinical Characteristics and Outcomes of Patients with Moderate-to-Severe Coronavirus Disease 2019 Infection and Diabetes in Daegu, South Korea |
| 64% lower mortality (p=0.1) and 52% lower progression (p=0.13). Retrospective 235 hospitalized diabetes patients in South Korea, showing lower mortality and lower progression to severe disease with metformin. | ||
Jul 31 2020 |
et al., Diabetes Care, doi:10.2337/dc20-0660 | Clinical Characteristics and Outcomes of Patients With Diabetes and COVID-19 in Association With Glucose-Lowering Medication |
| 33% lower mortality (p=0.46). Retrospective 120 COVID-19 diabetes patients, showing non-statistically significantly lower mortality with existing metformin treatment. | ||
Jul 14 2020 |
et al., Journal of Hematology & Oncology, doi:10.1186/s13045-020-00934-x | A tertiary center experience of multiple myeloma patients with COVID-19: lessons learned and the path forward |
| 58% lower mortality (p=0.43). Retrospective 58 multiple myeloma COVID-19 patients in the USA, showing non-statistically significant lower mortality with metformin treatment. | ||
Jun 23 2020 |
et al., Journal of Clinical Medicine, doi:10.3390/jcm9061959 | Clinical Characteristics and Disease Progression in Early-Stage COVID-19 Patients in South Korea |
| 120% higher progression (p=0.26). Retrospective 293 patients in South Korea, showing higher risk of progression with metformin use, without statistical significance. | ||
May 29 2020 |
et al., Diabetologia, doi:10.1007/s00125-020-05180-x | Phenotypic characteristics and prognosis of inpatients with COVID-19 and diabetes: the CORONADO study |
| 20% lower mortality (p=0.46). Analysis of 1,317 hospitalized COVID-19 patients with diabetes showing lower mortality with metformin use, without statistical significance. | ||
May 21 2020 |
et al., The American Journal of Tropical Medicine and Hygiene, doi:10.4269/ajtmh.20-0375 | Metformin Treatment Was Associated with Decreased Mortality in COVID-19 Patients with Diabetes in a Retrospective Analysis |
| 75% lower mortality (p=0.02). Retrospective 283 COVID-19+ diabetes patients in China, showing lower mortality with existing metformin treatment. | ||
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