Metformin given within a week of COVID-19 slashes risk of long COVID, death by 53%, paper notes

Popular diabetes drug offers new benefit

Meghan Holohan

Long COVID—or new-onset symptoms or worsening health conditions after SARS-CoV-2 infection—can lower quality of life. Finding a way to prevent it would be a welcome relief for those worried about the long-term effects of the viral infection. 

A study published last week in the Journal of Medical Virology finds that US COVID-19 patients prescribed metformin, a medication that treats prediabetes and type 2 diabetes, within six days of COVID-19 infection were less likely to develop long COVID or die. 

“Metformin prescription within the week following documented SARS-CoV-2 infection was associated with a 53% reduction in LC/D [long COVID or death] over 6 months in this primarily Omicron-infected sample,” wrote the authors, led by researchers from the University of Minnesota Medical School. 

Findings could help guide treatment recommendations

Using electronic health records, the scientists conducted a target trial emulation in COVID-infected participants. They compared 248 people who received a new metformin prescription within six days of diagnosis with the same number of controls prescribed the experimental treatments fluvoxamine, fluticasone, ivermectin, or montelukast within that same timeframe.

Half of the metformin cohort and more than half (52%) of the control group were infected with the Omicron SARS-CoV-2 variant. 

Metformin prescription within the week following documented SARS-CoV-2 infection was associated with a 53% reduction in LC/D [long COVID or death] over 6 months.

Overall, the weighted incidence of long COVID or death in patients receiving metformin or control treatment within six days of diagnosis was 6.3%: 4.0% in the metformin cohort and 8.5% in controls (absolute risk reduction, 4.5% for metformin).

“These results are also consistent with a recent sequential target trial analysis in the United Kingdom that assessed metformin started within 90 days of infection, HR [hazard ratio] 0.36,” the authors wrote. “The replication of results in clinical trials is important for informing treatment guidelines.”