Contrary to what several studies have shown, the results of a nationwide study of Danish children suggest that antibiotic use does not affect the development of type 1 diabetes.

As a possible mechanism for this association, investigators have proposed that the use of antibiotics in childhood affects the gut microflora (the normal balance of micro-organisms in the gut), which in turn influences the gut immune system. Dysfunction in this immune system is thought to be involved in the development of type 1 diabetes, according to the report in the March 24 online issue of the American Journal of Epidemiology.

“Research hinting at a potential association between antibiotic use in childhood and immunologic health is accumulating,” comment study authors Drs. Anders Hviid and Henrik Svanstrom from Statens Serum Institut, Copenhagen. However, most of the studies have not looked at this association with any detail, but focused on infections and vaccinations instead.

The current investigation featured 606,420 children who were born in Denmark from 1995 to 2003. The researchers classified the children’s antibiotic use based on drug class, number of uses, and age at use.

No amount of antibiotic use had a significant relationship on the risk of developing type 1 diabetes, the authors note. This held true after they performed a number of subanalyses looking at drug class, number of courses taken, and age at use.

The present findings, the authors conclude, suggest there is no association between antibiotic use and type 1 diabetes. Nonetheless, there remains a need for “large, analytical studies of the long-term health effects of drug use in susceptible groups, such as children, and especially so for drugs used as prevalently as antibiotics and for common chronic diseases, such as type 1 diabetes.”

SOURCE: American Journal of Epidemiology, March 24, 2009.