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New Study Finds Antibiotic Use In Babies Is Linked To Chronic Health Issues Like Allergies & Asthma

Could one of the most common medications prescribed to infants be hurting them down the road?

In studying the health records of more than 14,000 children, researchers at the Mayo Clinic have found that antibiotic use in babies is linked to ongoing illness and chronic health issues later in life. Children who received at least one dose of a prescribed antibiotic before their second birthday were more likely to develop immunological, metabolic, or neurobehavioral health conditions like asthma, allergies, or obesity, according to a new study published Sunday in Mayo Clinic Proceedings.

"The present study highlights the prevalent use of antibiotics in infants and reveals concerning associations between exposure to antibiotics and distinct immunological, metabolic, and neurobehavioral health conditions and the occurrence of combinations of these conditions during childhood," researchers noted in their study. "The health risks associated with antibiotic exposure in the first two years of life relate to the number, type, and timing of prescriptions. Notably, the association between antibiotic exposures and adverse health outcomes, including asthma, allergic rhinitis, atopic dermatitis, celiac disease, overweight, obesity, ADHD, and learning disability persisted after adjusting for recognized and important infant and maternal confounders."

Researchers studied 14,572 children born in Olmsted County, Minnesota, between Jan. 1, 2003, and Dec. 31, 2011, periodically checking in with the children's medical records over the course of nearly nine years. Of the study's participants, 70% were prescribed at least one antibiotic in their first two years of life and 55.4% received three or more doses of antibiotics. Interestingly, researchers found that what antibiotic children received and when they received it appeared to play a role in which immunological, metabolic, or neurobehavioral health conditions children developed.

For example, researchers noted that penicillin, cephalosporins, and macrolides were found to be the most commonly prescribed antibiotics — and children who took them between birth and age 2 were found to be more likely to develop certain chronic health conditions.

"Exposure to cephalosporins was associated with an increased risk of the highest number of conditions and, uniquely, autism and food allergies," researchers wrote. "Penicillins were associated with an increased risk of asthma and [being] overweight in both sexes, celiac disease and ADHD in girls, and obesity in boys... Macrolides were associated with an increased risk of asthma and [being] overweight in both sexes and allergic rhinitis [or hay fever] and obesity in boys, but were associated with a reduced risk of atopic dermatitis [or eczema] in girls and learning disability in boys."

But before you throw out or disregard the antibiotic your child's doctor prescribed, it's worth noting that researchers stressed their work had only identified a link between early antibiotic use and health conditions with childhood-onset, rather than a cause. "We want to emphasize that this study shows association, not causation, of these conditions," Nathan K. LeBrasseur, a researcher at the Mayo Clinic's Department of Physical Medicine and Rehabilitation and one of the study's authors, told CNN. "These findings offer the opportunity to target future research to determine more reliable and safer approaches to timing, dosing and types of antibiotics for children in this age group."

Researchers hypothesized that the microbiome composition and interactions that happen in the first few years of life proved critical to the development of a healthy immune system and that the disruptions antibiotics can have on microbial composition could have long-term consequences on the immune system. Still, they stressed more studies are needed to fully understand the link. "When antibiotics were first developed and deployed, the overwhelming consideration was control of pathogens. We now realize that their widespread application has considerable collateral effect on the microbiome, which may be of special importance in developing children," they noted in the study. "With further study, practical clinical guidelines can be established to optimize the benefit and minimize the risk of antibiotics in children."

Studies referenced:

Aversa, Z., Atkinson, E. J., Schafer, M. J., Theiler, R. N., Rocca, W. A., Blaser, M. J., & LeBrasseur, N. K. (2020). Association of Infant Antibiotic Exposure With Childhood Health Outcomes. Mayo Clinic Proceedings. doi:10.1016/j.mayocp.2020.07.019