Study Finds That Mild COVID-19 Cases Are Linked with Higher Diabetes Risk

It’s long been known that COVID-19 tends to hit people with diabetes much harder, but mounting evidence has shown that COVID-19 infections may also be linked with subsequent diabetes diagnoses. A recent study out of Germany found something similar, even among those with mild infections.

A team including researchers from the German Diabetes Center at Heinrich Heine University in Dusseldorf examined data from nearly 1,200 medical practices across Germany, comparing type 2 diabetes diagnoses in those who had recovered from a mild case of COVID-19 versus those who had recovered from other respiratory infections during the same stretch. The findings, published in the journal Diabetologia, show that the incidence of diabetes was much higher in the COVID-19 group. There are some theories as to why.


Lead author, Professor Wolfgang Rathmann, says, “COVID-19 infection may lead to diabetes by upregulation of the immune system after remission, which may induce pancreatic beta cell dysfunction and insulin resistance, or patients may have been at risk for developing diabetes due to having obesity or prediabetes, and the stress COVID-19 put on their bodies speeded it up.”

To investigate the link between COVID-19 and subsequent diabetes diagnoses, the researchers looked at health records from 8.8 million adults who visited 1,171 general and internal medicine practices throughout Germany between March 2020 and January 2021. Of those, 35,865 had been diagnosed with COVID-19. The team compared this group with patients who had been diagnosed with an acute upper respiratory tract infection during the same time frame and who matched the first group’s demographics, including sex, age, health insurance coverage, month of infection diagnosis, and comorbidities.

Over an average follow-up period of about four months for COVID-19 and a little over five months for the other infections, the hospitalization rates were about the same, at just over 3%. The median number of hospital stays was also 1 for both groups. However, those who had been diagnosed with COVID-19 were 28% more likely to later develop type 2 diabetes, with a rate of 15.8 per 1000 people versus 12.3 per 1000.


Going forward, it’s unclear if this will be permanent, however.

Professor Rathmann says, “Since the COVID-19 patients were only followed for about three months, further follow-up is needed to understand whether type 2 diabetes after mild COVID-19 is just temporary and can be reversed after they have fully recovered, or whether it leads to a chronic condition.”

The study authors note that while it’s unlikely that most people who recover from COVID-19 will have this issue, it’s a good idea to talk to your doctor if you notice yourself suffering from any symptoms of diabetes after a COVID infection.

The team highlighted a couple of limitations of their study, including a lack of data on body mass index and the fact that the findings may not be generalizable to the whole population.

An earlier study by the CDC found that children were also more apt to be diagnosed with diabetes after a COVID-19 case, compared with those who had dealt with other infections pre-COVID and those who had not had COVID.

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