Another late consequence of corona: Infection with the corona virus increases the risk of type 2 diabetes – even with a mild course of Covid-19, as a German study reveals. According to this, the risk of illness in recovered corona patients is 28 percent higher than in people who were infected with other respiratory viruses. This confirms evidence that SARS-CoV-2 can damage the insulin-producing cells of the pancreas.
There has long been a suspicion that Coronavirus SARS-CoV-2 can cause other late effects in addition to Long Covid. There was already an increase at the beginning of the corona pandemic case reports regarding previously healthy patients who suddenly developed abnormal blood sugar levels and diabetes following surviving Covid-19 disease. Tests on cell cultures and autopsy findings have since confirmed that a corona infection Damage to the beta cells in the pancreas – the cells that produce the blood sugar hormone insulin.
A good 35,800 German corona patients as a test group
But how often does diabetes occur as a late consequence of corona? And how high is the risk compared to infections with other respiratory viruses? Researchers led by Wolfgang Rathmann from the Heinrich Heine University in Düsseldorf have now investigated this. For their study, they evaluated health data from a total of eight million patients who were treated in over 1,700 medical practices across Germany from March 2020 to January 2021.
Using this data, they compared the frequency of newly occurring diabetes in 35,865 Covid-19 patients following surviving the infection and in the same number of comparison people who had contracted another respiratory virus. All patients had previously normal blood glucose levels and were comparable in pre-existing conditions and risk factors. The severity of the predominantly mild courses was also comparable in both groups.
28 percent more diabetes cases
The comparative analyzes showed that patients developed new type 2 diabetes more frequently following contracting Covid-19 than following another viral infection. With Covid-19 it was 15.8 people per 1,000, with other viruses 12.3 per 1,000, as Rathman and his team report. Converted, this means that the diabetes risk following a coronavirus infection is around 28 percent higher than a flu or cold.
“Covid-19 therefore increases the risk of type 2 diabetes,” the researchers write. This applies even to a mild course. “Given that almost half a billion people worldwide have already experienced an infection with SARS-CoV-2, these are important results,” comments Betty Raman, a medical doctor from the University of Oxford who was not involved in the study. “The increased occurrence of diabetes following mild infections is particularly surprising.”
Unanswered questions remain
Rathmann and his colleagues assume that a number of factors play a role in this late corona effect. This includes virus-related damage to the beta cells, but also an increased inflammatory response of the immune system to the infection. But indirect factors such as weight gain or lack of exercise during the pandemic cannot be ruled out either.
It is also still unclear whether the diabetes that occurs following Covid-19 will remain permanent or improve once more over time. This is because the patient data was only recorded for an average of three months. According to the team, further investigations are therefore necessary. Nevertheless, they advise that people with a mild course of Covid-19 should also be monitored for diabetes and elevated blood sugar following the infection has been overcome.
In any case, further studies are now necessary to examine the occurrence of diabetes following Covid-19 disease and the risk factors leading to it in more detail. It also needs to be investigated whether and to what extent a coronavirus infection can also have this late effect in vaccinated people. (Diabetologia, 2022; doi: 10.1007/s00125-022-05670-0)
Those: Diabetology