Early life infections may be a risk factor for celiac disease in childhood

Children with frequent infections in the first 18 months of life have a slightly increased risk of later developing coeliac disease compared with children who have few infections. This is the conclusion from a study by the Norwegian Institute of Public Health.

Coeliac disease is an immune-mediated disease triggered by gluten, a protein found in wheat, rye and barley. In recent decades there has been a marked increase in the prevalence of coeliac disease and it is believed that one per cent of the population in Western countries, including Norway, has the disease. The increased occurrence of coeliac disease, together with results from twin studies, indicates that environmental factors play a significant role in the development of the disease. However, besides gluten the environmental factors that trigger coeliac disease are largely unknown.

Immunological research suggests that infections may be a possible risk factor for developing coeliac disease. Population studies have shown that children admitted to hospital for an infection are at an increased risk for coeliac disease later in childhood. However, it has been unclear whether this association is related to the infection itself, or whether hospital admission leads to an increased likelihood of being tested for coeliac disease.

30 per cent increased risk

The researchers studied the relationship between infection frequency during the first 18 months of life and the risk of coeliac disease later in childhood.

In the current study 72,921 children born in 2000-2009 in Norway were followed with repeated questionnaires with information on respiratory infections and gastroenteritis during the first 18 months of life. Children who later developed coeliac disease were identified through parental questionnaires and the Norwegian Patient Register.

The results show that:

After an average of 8.5 years of follow up, 581 children (0.8 per cent) had developed coeliac disease.

Children with ten or more infections during their first 18 months had an approximately 30 per cent increased relative risk of subsequent coeliac disease compared with children with fewer than five infections.

The study found broadly consistently increased relative risks for coeliac disease in relation to infections at 0-6 months and at 6 to 18 months of age, as well as similarly increased risks in children with repeated respiratory tract infections compared to those with repeated gastrointestinal infections.

Can infections alter the immune system?

The study supports the hypothesis that infections may affect the risk for coeliac disease and the results may provide an etiological clue for what triggers the disease. Previous studies have suggested that infections, either through a direct effect on the intestine or through changes in the immune system, may increase the risk of coeliac disease.