More children are being diagnosed with coeliac disease, diabetes, and Crohn's

Research shows that more children are being diagnosed with conditions such as coeliac disease, type 1 diabetes, and inflammatory bowel disease (IBD) than before. IBD is a term for conditions like ulcerative colitis and Crohn's disease.

These are all autoimmune diseases, which are the most common chronic diseases in children.

“These diseases are characterised by the immune system attacking the body's own cells. They can be diseases of most organs such as the hormonal system, joints, intestines, or nervous system,” says Ketil Størdal.

He is a professor at the University of Oslo, and a pediatrician and group leader at Oslo University Hospital.

Together with colleagues, he has recently conducted a large study on how many children in Norway have one or more autoimmune diseases.

“We are trying to understand why more children are getting these diseases now than before,” he says.

Coeliac disease is the most common in children

The researchers studied six autoimmune diseases: coeliac disease, type 1 diabetes, inflammatory bowel disease (IBD), autoimmune thyroiditis, juvenile arthritis, and autoimmune liver disease.

They used data from nearly one million children born in Norway between 2004 and 2019, and linked four different health registries.

Their findings showed that 2.6 per cent of the children developed at least one autoimmune disease during childhood, before they turned 18.

“Coeliac disease is the disease most children get, followed by type 1 diabetes and autoimmune thyroiditis,” says Størdal. “Both diabetes and inflammatory diseases of the bowel, such as coeliac disease and IBD, have increased quite significantly in the past few decades. Yet we don’t know why this has happened.”

Størdal treats children with these diseases as part of his job as a pediatrician.

A child with diabetes can also get coeliac disease or juvenile arthritis

The researchers also found that it is quite common for children who get one of these diseases to also get one or more other autoimmune diseases.

“These diseases are so closely related that the same children often get more of them during their childhood. We looked at those who had turned 18. Of those with an autoimmune disease, about 8 per cent had at least one additional autoimmune disease,” Størdal says.

He believes these findings are important in how we detect and treat these conditions.

But not all six diseases were related.

“IBD was not related to type 1 diabetes nor to autoimmune metabolic disease,” the researcher points out.

Risk associated with where the children live

The researchers also studied where in Norway the children who had autoimmune diseases lived.

They found that there were large geographical differences.

“Children in Northern Norway have a higher risk of getting three of these diseases than children living in Central Norway," says Størdal.

Children living farthest south in Norway have the lowest risk.

“We're looking for an explanation as to why this is so,” the researcher says.

Different factors play a role

In the search of an explanation, the research team have looked into what might contribute to an increased risk of getting an autoimmune disease.

They will also conduct further research on this.

“We have data on genetics from the Norwegian Mother, Father and Child Study that we can use to map whether there are regional differences in genetic vulnerability. It's conceivable, although we don't think it explains everything,” he says.

The researchers are also looking at the physical environment in which the children grow up. These are called environmental factors.

“We're studying diet. We're also looking at whether being close to nature or in more grey surroundings such as in cities and towns has something to do with it. In addition, we look at the use of antibiotics. We know that there is a lot of variation in this depending on where you live,” says Størdal.

Norway is a long country area-wise, and the regional differences are a clue to finding biological explanations.

“Vitamin D is an example of something that can vary with where you live. But we have already studied this and don't think that it explains the differences,” the researcher says.

Awareness is good for parents

Giving general advice to parents is difficult, according to Størdal.

“But it's clear that knowing that these diseases are to some extent related can be beneficial,” he points out.

He also thinks that it's important for parents to be able to trust that the doctors who take care of their child's illness know that they may have multiple autoimmune diseases.

"Then they can adapt the treatment and follow-up accordingly,” he says.

Considering other diseases

It is important that doctors and other healthcare workers know about the connection. They should adapt diagnosis, follow-up, and treatment.

“We must pay close attention. Tests should be carried out if there is reason to suspect, for example, that a child with juvenile arthritis has a disease in the intestine or liver. We should have a low threshold for checking,” says Størdal.

He adds that it's important that the course of treatment is adapted to the patient.

“I think it's important that patients who have multiple illnesses receive a coherent follow-up. That we as providers of care coordinate and, as far as possible, provide a comprehensive treatment plan,” he says.

References:

Andersen et al. Specific phenotypes may drive an increased incidence of pediatric inflammatory bowel disease in South‐Eastern Norway, Journal of Pediatric Gastroenterology and Nutrition, 2025. DOI: 10.1002/jpn3.70148

Beitnes et al. Symptoms and mucosal changes stable during rapid increase of pediatric celiac disease in Norway (Abstract), Journal of Pediatric Gastroenterology and Nutrition, 2017. DOI: 10.1097/MPG.0000000000001307

Stene, L.C. & Haynes, A. Trending now: modelling global epidemiology of type 1 diabetes in children and adolescents (Abstract), The Lancet Diabetes & Endocrinology, 2022. DOI: 10.1016/S2213-8587(22)00306-0

Størdal et al. Incidence and co-occurrence of six autoimmune diseases in childhood: a population-based cohort study in Norway (Abstract), The Lancet Child & Adolescent Health, 2026. DOI: 10.1016/S2352-4642(26)00008-8

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