Yet another study has found an increased risk of dying from coronavirus among obese diabetic people – but a drug commonly taken to treat the chronic condition offered protection, at least to one group: women.
Metformin is commonly prescribed to counteract the overproduction of sugar by the liver and to improve the body’s response to insulin.
The researchers from the University of Minnesota hoped that if it can treat risk factors for severe or deadly coronavirus infection, it might also reduce the risks of these outcomes.
Their study of more than 15,000 people – one of the largest in the world to-date – found that the drug reduced the risk that women would die of coronavirus by up to 24 percent, but it didn’t seem to confer the same protection for men.
Diabetic and obese women taking the blood sugar control drug, metformin, which costs about $16, saw lower risks of dying of coronavirus after being hospitalized for the infection
Leading risk factors for dying of coronavirus include age, race, and chronic conditions.
It’s become increasingly clear that among chronic conditions, obesity and diabetes are at the top of the list of risk factors.
People who are overweight or diabetic have higher levels of baseline inflammation.
Often, it is out of control inflammation from a flailing immune response to coronavirus that lead kills COVID-19 patients, rather than coronavirus itself.
So those that suffer higher levels of inflammation before they catch coronavirus are at a heightened risk of getting severely ill or dying from the infection.
In the absence of a treatment designed specifically to counteract coronavirus itself, or a vaccine to prevent infection, scientist have been testing various existing medications, including antivirals that might interfere with coronavirus’s ability to make copies of itself, as well as inflammation-fighting drugs.
Metformin is the fourth most commonly prescribed drug in the US, according to Mayo Clinic.
It’s typically a first line of treatment for people diagnosed with type 2 diabetes, including some 30 million Americans.
Insulin resistance that characterizes diabetes leads to the buildup of sugar, or glucose in the blood, both of which lead to inflammation (and inflammation itself can make the body even more insulin resistant).
Metformin helps to manage blood sugar levels, and thus inflammation levels.
There were 15,380 people hospitalized with coronavirus and enrolled in the study. Of them, 6,256 had been diagnosed with either diabetes or obesity.
Of the diabetic or obese patients, 2,333 had metformin prescriptions.
Nearly 19 percent of all those who were obese or diabetic and hospitalized for coronavirus ultimately died in the hospital.
In total, those taking metformin were 16 percent less likely to die of coronavirus.
Women who were on metformin were 21 to 24 percent less likely to die of the infection – a statistically significant reduction in risks.
It’s not entirely clear why women would see such benefits, but men would not.
However, it’s hardly the first sex difference reported in coronavirus severity.
Across the board, men are more likely to become severely ill or die from the disease, though the exact disparity varies from study to study and region to region.
At first, researchers believed it may be due to higher rates of smoking among men – particularly in China, before coronavirus reached pandemic scale.
Some research suggests that the difference might be genetic, citing the location of the gene that contains instructions for the receptor through which the coronavirus enters human cells on the X chromosome.
Because women have two X chromosomes, a good copy of the ACE2 gene could offset the consequences of the ‘bad’ variation that makes it easier for the virus to enter.
In diabetic or obese men and women, the University of Minnesota researchers noted that men tend to have higher levels of inflammation at earlier ages and stages of their conditions, which may dampen the benefits of metformin.
They also suspect that the difference in how metformin works in people of different sexes is linked to another receptor involved in coronavirus susceptabiity.
More studies are needed to know just how helpful metformin is to women – or if it could help men with coronavirus if given at different doses – but if it continues to prove effective, the $16 medication could be a cheap way to protect vulnerable people from COVID-19’s most devastating effects.