Childhood antibiotics linked to type 1 diabetes

A link between giving children antibiotics and type 1 diabetes has been found in a study, which was carried out on mice.

In doses equivalent to those given to children, researchers said antibiotics changed the mix of gut microbes in young mice to dramatically increase their risk for type 1 diabetes.

As children’s exposure to antibiotics has increased in recent decades, experts say autoimmune diseases like type 1 diabetes have more than doubled.

Researchers from New York University compared the health of mice given several courses of antibiotics when young with those not given any drugs.

Those given three antibiotic treatments by the age of six weeks – roughly two-and-a-half years old in human terms – were twice as likely to develop diabetes as those not given antibiotics.

Males may be particularly vulnerable, the journal Nature Microbiology reports.

Importantly, the doses of drugs used mimicked those frequently given to children.

Plus, the mice studied were genetically prone to developing type 1 diabetes – to mirror the effect of a child coming from a family with a history of the condition.

Lead author Martin Blaser of the New York University’s Langone Medical Center, said: “Our study begins to clarify the mechanisms by which antibiotic-driven changes in gut microbiomes may increase risk for type 1 diabetes.

“This work uses NOD mice, the best model of type 1 diabetes to date, and doses of antibiotics like those received by most children to treat common infections.”

Friendly bacteria

Some 400,000 Britons, including almost 30,000 children, have the condition and it is becoming more and more common.

The rise is particularly sharp among very young children, with number of under-fives with type 1 diabetes going up five-fold in the past 20 years.

The US researchers believe certain gut bugs teach the immune system not to mount such an attack.

If these friendly bacteria are missing early in life – because they are killed off by antibiotics – the disease may develop.

Finally, when the researchers took some bugs from the antibiotic-treated mice and gave them to germ-free mice, their immune systems changed.

Jessica Dunne, director of discovery research at the Juvenile Diabetes Research Foundation (JDRF), said: “This latest study result is compelling, linking the effects of use of antibiotics in mice to type 1 diabetes.

“This is the first study of its kind suggesting antibiotic use can alter the microbiota and have lasting effects on immunological and metabolic development, resulting in autoimmunity. We’re eager to see how these findings may impact the discovery of type 1 diabetes preventative treatments in the future and continued research in the area of vaccines.”

Dr Blaser said if certain bugs are found to be particularly good at training the immune system to develop normally, children at risk of type 1 diabetes could eventually be given them as a probiotic treatment.

Similarly, if other bugs direct the immune system to attack the pancreas, it may be possible to vaccinate children against them and stop them from becoming diabetic.

Dr Blaser stressed parents should still give their children antibiotics, as advised by their GP.

The JDRF said it was excited by the study’s potential but more work is needed to see how relevant the results are to people.

While it may seem odd to link a serious health condition to antibiotic use, asthma, obesity and digestive problems have all been associated with the drugs.