COVID-19 could set off diabetes in some folks


Emerging data suggests that COVID-19 may trigger diabetes in some people, although the exact cause remains unknown.

Scientists around the world saw an increase in new diabetes cases over the past year, noting that some COVID-19 patients with no history of diabetes suddenly developed the disease, Scientific American reported. The trend prompted many research groups to start studies on this phenomenon. For example, researchers at King’s College London in England and Monash University in Australia have set up the CoviDiab registry, a resource that doctors can use to submit reports on patients with a confirmed history of COVID-19 and newly diagnosed diabetes.

Emerging data suggests that COVID-19 may trigger diabetes in some people, although the exact cause remains unknown. (iStock)

More than 350 clinicians have submitted reports to the registry, The Guardian reported. They have reported both type 1 diabetes, where the body attacks the cells in the pancreas that make insulin, and type 2 diabetes, where the body still makes some insulin, although it is often not enough and its cells do not respond properly to the hormone.

“In the past few months we have seen more cases of patients who had diabetes either during the COVID-19 experience or shortly afterwards,” said Dr. Francesco Rubino, professor and chair of metabolic and bariatric surgery at King’s College London, said the Guardian. “We are now beginning to believe that the link is likely true – the virus’ ability to cause glucose metabolism to malfunction.”


Other studies have found a link between COVID-19 and diabetes.

For example, a review of eight studies that included more than 3,700 hospitalized COVID-19 patients found that around 14% of those patients developed diabetes, Scientific American reported. A preliminary study of 47,000 UK patients found 4.9% had diabetes, The Guardian reported.

“We can clearly see that people without a history of diabetes get diabetes,” said Dr. Remi Rabasa-Lhoret, a physician and metabolic disease researcher at the Montreal Clinical Research Institute, told CTV News. “It is very likely that COVID-19 will cause the disease.”

The big question is why and scientists have multiple theories.

SARS-CoV-2, the virus that causes COVID-19, may directly attack insulin-producing cells in the pancreas, Scientific American reported. Alternatively, the virus can indirectly damage these cells by infecting other parts of the pancreas or the blood vessels that supply the organ with oxygen and nutrients. Another theory is that the virus infects other organs involved in blood sugar regulation, such as the intestines, and somehow undermines the body’s ability to break down glucose in general.


Other types of viruses – like certain enteroviruses, which cause various diseases including hand, foot, and mouth diseases – have been linked to diabetes in the past, The Guardian reported. In addition, a subset of patients infected with the SARS-CoV coronavirus, which caused outbreaks of severe acute respiratory syndrome in the early 2000s, later developed diabetes. Dr. Mihail Zilbermint, an endocrinologist and associate professor at the Johns Hopkins School of Medicine, told CTV News.

In general, acute viral infections can cause severe inflammation in the body, and in response, the body produces stress-related hormones, such as cortisol, to help reduce the inflammation. Stress hormones can cause blood sugar levels to spike, and that spike doesn’t always subside after the infection clears, Scientific American reported.

In addition, COVID-19 patients are often treated with steroid drugs such as dexamethasone, which can also increase blood sugar levels. Hence, it is possible that these steroids could also contribute to the incidence of diabetes in COVID-19 patients, Zilbermint told CTV News. Steroid-induced diabetes may resolve after the patient stops taking the medication, but sometimes the condition becomes chronic, according to


However, another factor that adds to the uncertainty about the link is how many of the patients already had prediabetes, which means they had above-average blood sugar levels when they received COVID-19. “It is possible that [a] The patient has lived with prediabetes for many years and didn’t know it, “Zilbermint told CTV News.” Now they have COVID-19 infection and the infection is driving them to develop diabetes. “

Scientists aren’t sure if the people who develop diabetes after taking COVID-19 will have the disease permanently, Rabasa-Lhoret told CTV News. At least some patients who developed diabetes after contracting SARS had their diabetic symptoms eventually subsided and their blood sugar returned to normal after the infection. This comes from a report from 2010 in the journal Acta Diabetologica. Similar, short-lived diabetic symptoms may occur in patients infected with SARS-CoV-2. However, this needs to be confirmed by further studies.

Originally published on Live Science.