A new study examining patient medical records has found that people who recovered from COVID-19 had a heightened risk of being diagnosed with diabetes within a year of infection compared with someone who had not been infected.
The study, published Monday in the journal Lancet Diabetes and Endocrinology, found that roughly 2 in 100 people who tested positive for the virus were later diagnosed with diabetes. This was no matter the severity of COVID-19 infection ― including those who were asymptomatic ― or if the patient had any prior risk factors for developing diabetes, the study’s co-author, Dr. Ziyad Al-Aly, told HuffPost.
“It’s happening in some cases where people had no risk factors at all. Meaning they did not have obesity, they did not have high cholesterol, did not have any of the manifestations that would be considered risk factors for diabetes,” said Al-Aly, who serves as the chief of research and development at the Veterans Affairs St. Louis Health Care System and who is a clinical epidemiologist at Washington University in St. Louis.
The study examined the records of 181, 280 Department of Veterans Affairs patients who tested positive for COVID-19 between March 1, 2020, and Sept. 30, 2021. These records were then compared with more than 8 million VA patients who either had not tested positive during that same period or who received VA medical care in the two years prior to the pandemic.
Researchers found that those diagnosed with the virus were 46% more likely to later develop diabetes or be prescribed medication to control blood sugar, Al-Aly said.
The vast majority of the study’s participants found to have been diagnosed with diabetes had Type 2 diabetes rather than Type 1. Type 2 diabetes is a condition in which the pancreas makes insufficient amounts of the hormone insulin, which regulates the movement of sugar in cells. When insulin levels are too low, sugar levels can get too high in the bloodstream, potentially leading to disorders of the circulatory, nervous and immune systems, according to the Mayo Clinic.
As for why the diabetes risk would increase after infection, Al-Aly said he thinks it relates to how the body’s immune system responds to the virus, with it triggering inflammation that could then impair insulin secretion and sensitivity.
Because the study found a heightened risk of diabetes so long after infection, he said it appears as though little, if any, of the effects may be reversible.
“This is more of an awareness situation. We want people to know but not panic,” he said. Al-Aly recommended that anyone who has been diagnosed with COVID-19 get screened for diabetes, adding that the earlier one is diagnosed, the better their outcome.
Maren Laughlin, a program director at the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases, who reviewed the study, told The Wall Street Journal that it was very well done. She said its main limitation was the patients’ demographics, with VA patients generally tending to be older and sicker and to include more males than are in the broader population.
Al-Aly said he does not believe that the study was limited because of this, however, and stressed that the number of patients considered from broader groups was “not small.”
Other post-pandemic studies have sounded similar alarms about an association between COVID-19 and diabetes. The coronavirus now is known to cause not just respiratory symptoms but also long-term effects on multiple organ systems, such as the kidneys, skin, gastrointestinal tract, heart and brain. Some of these effects, which have been called long COVID, can last for weeks or more.
One pediatric report published by the Centers for Disease Control and Prevention in January found that children younger than 18 had an increased risk of being diagnosed with diabetes at least 30 days after a COVID-19 infection.
That report also found no definite cause and effect but, similar to Al-Aly’s study, it suggested that the diabetes diagnosis could be the result of the virus’s effects on organ systems involved in diabetes risk, such as on pancreatic cells. It was also suggested that weight gain during the pandemic may have indirectly increased the risks for diabetes.
Another report by the CDC last fall found that the body mass index (BMI) for children and teenagers roughly doubled during the pandemic when compared with a pre-pandemic period. The largest increases were seen among youths who were already overweight or obese and those who were younger school-aged students.