An analysis of eight studies suggests that children who take antibiotics before they are one-year-old may double their risk of developing asthma later.

The researchers say an increase in asthma, which is the most common chronic childhood disease, coincides with an increase in the use of antibiotics in young children.

This suggests that the two are linked. However, MedPage Today

Carlo Marra, Pharm.D., Ph.D., of the University of British Columbia, says "our overall results show that treatment with at least one antibiotic as an infant appears to be associated with the development of childhood asthma."

The researchers analyzed studies which included 12,082 children and 1,817 cases of asthma.

The analysis showed:

Overall, the odds ratio for developing asthma after antibiotic exposure was 2.05, with a 95 percent confidence interval from 1.41 to 2.99. The retrospective studies showed a strong association, with an odds ratio of 2.82 and a 95 percent confidence interval from 2.07 to 3.85. The association in the prospective studies failed to reach statistical significance, with an odds ratio of 1.12, but a 95 percent confidence interval from 0.88 to 1.42.

Their findings appear in the March issue of CHEST.