Covid-19 infection may increase the risk of type 1 diabetes, a nationwide study of 1.2 million children suggests.
Researchers in Norway examined the risk of young people developing new-onset type 1 diabetes within or after 30 days after infection. They compared this group with children and adolescents in the general population who did not have a registered infection, as well as to a group of children who were tested but found to negative for the virus.
Over the two year study period, a total of 424,354 children tested positive for Covid and 990 new-onset cases of type 1 diabetes were diagnosed among the 1.2 million children and adolescents included in the study. After adjusting for age, sex, country of origin, geographical area and socio-economic factors, the analyses found that young people who contracted Covid were around 60 per cent more likely to develop type 1 diabetes 30 days or more after infection compared to those without a registered infection or who tested negative for the virus.
However, the authors said the exact reason for the increased risk of type 1 diabetes in young people after Covid is not yet fully understood and requires longer-term follow-up and further research into whether the risk could be different in children who are infected with different variants.
Dr Hanne Løvdal Gulseth, lead author and research director at the Norwegian Institute of Public Health, said: “Our nationwide study suggests a possible association between Covid-19 and new-onset type 1 diabetes. However, the absolute risk of developing type 1 diabetes increased from 0.08 per cent to 0.13 per cent, and is still low.
“The vast majority of young people who get Covid-19 will not go on to develop type 1 diabetes but it is important that clinicians and parents are aware of the signs and symptoms of type 1 diabetes. Constant thirst, frequent urination, extreme fatigue and unexpected weight loss are tell-tale symptoms.”
The findings will be presented today/on Friday at The European Association for the Study of Diabetes in Stockholm.
Independent scientists said although there are a number of credible reasons why Covid might lead to development of type 1 diabetes, this remains in no way proven. Increased testing at time of infection and delays in seeking care could possibly explain the links observed.
It is also possible that other factors which occurred during the pandemic – including behaviour of other viruses linked to type 1 diabetes, and changes in exposure to vitamin d from less time spent outdoors, could lead to an increase in cases.
Dr Gareth Nye, senior lecturer at the University of Chester, said: “The finding that a novel virus may increase risk of type 1 diabetes is not surprising considering the current knowledge pool however the risk reported in both cases is still incredibly small and the vast majority of the population will not develop the condition however, with lockdown procedures in place in the reported countries we may be seeing an artefact of children being around parents or guardians for a greater proportion of time, with a heightened sense of concern brought about from the pandemic which is why children are being diagnosed so close to a positive test.”