2 September 2019

Gluten may awaken coeliac disease in at-risk kids

Allergies Clinical

Gluten may trigger coeliac disease in some toddlers who are genetically predisposed to the condition, a Swedish study suggests.

The prospective, observational study, published in JAMA, followed around 6,600 newborns that were at high genetic risk of developing coeliac disease.

During the study, parents recorded their baby’s diet starting at six months of age.  Overall, 447 babies (7%) developed coeliac disease before the age of five.

But babies who were given more bread or pasta than the average infant were significantly more likely to develop coeliac disease.

In the study, eating 1g more gluten per day than the average baby (corresponding to an additional half slice of white bread) was associated with a 50% increased risk of coeliac disease by age three.

The risk of coeliac disease increased two-fold in children who ate the highest amounts of gluten compared with the children who ate the lowest.

This latest study reinforced a 2002 population-based study from Sweden, which reported that children with coeliac disease were fed more gluten as babies.

While these studies point to a possible link between gluten consumption early in life and coeliac disease, experts warned against leaping to conclusions.

“I would urge caution about over-interpreting the results of this study and rushing to revise clinical recommendations,” said Associate Professor Jason Tye-Din, a gastroenterologist and the chair of Coeliac Australia’s medical advisory committee.

“While some parents may wish to reduce excessive amounts of gluten in their infant’s diet, there is no evidence that removing all gluten is helpful, and in fact is likely to unnecessarily restrict and worsen the child’s nutrition,” he said.

“A broad nutritious diet, that includes breastfeeding when possible, is recommended.”

Babies are generally considered to be at increased risk of coeliac disease if they have a parent or sibling with coeliac disease and the susceptible genotype.

Dr Suzanne Mahady, a gastroenterologist at Monash University, agreed that it was “premature to start excluding gluten in the diet of all at-risk children based on this study”.

“The study was observational, not experimental, which means we can’t be sure that there are not other dietary or environmental factors at play, that are themselves causing the increased risk of coeliac disease,” she said.

The study did not measure the amount of gluten directly, relying instead on self-reports from parents. “This could have introduced some error into the results,”  Dr Mahady said.

There was also some conflicting evidence in the literature, including an RCT published in the New England Journal of Medicine showing that introducing gluten early (at four to six months) did not increase or decrease the subsequent risk of coeliac disease.

“A prospective study in the same TEDDY cohort showed no difference in coeliac disease rates in offspring of mothers with low/medium/high gluten intake in pregnancy,” Dr Mahady said. “This finding is inconsistent with the current study.”

JAMA 2019, 13 August