Childhood Asthma Linked to Early Antibiotic Use

A new study shows that children given antibiotics during their first year of life are more likely to develop asthma by age seven. The authors have taken into account other well known risks for asthma, basing their conclusions on an analysis of 13, 116 children who received antibiotics for non-respiratory tract infections early in life. The incidence was highest for children who received more than four courses of antibiotics,

Anita L. Kozyrskyj, PhD, from the University of Manitoba in Winnipeg, Canada, and colleagues write, "Antibiotic use in early life was associated with the development of childhood asthma, a risk that may be reduced by avoiding the use of BS [broad-spectrum] cephalosporins." Cephalosporins are a widely used class of antibiotics that are a cousin to Penicillin, and treat a variety of bacteria. The strongest link was found in children whose mother did not have asthma and in homes without dogs.

The researchers are not exactly sure what contributes to the findings. Past studies have shown that kids who are exposed to bacteria fare better - their immune systems get a boost when they’re exposed to germs. Hygienic environments seem to suppress the development of T-helper type 2 immunity, an issue addressed in the March 2003 issue of the Journal of Allergy and Clinical Immunology. Allergic hypersensitivity (atopy) has been seen in children who require antibiotics, and are not exposed to pets, according to a 2005 study also published in the Journal of Allergy and Clinical Immunology, conducted by Johnson and colleagues. Chest published an analysis in March 2006 that showed an increased risk of asthma when children receive antibiotics during their first year of life.

The study concludes, “"While we have constructed our study to diminish the likelihood of reverse causation and confounding bias, and have implemented a validated definition of childhood asthma, we can neither confirm nor refute the causative role of antibiotics in the development of asthma," the authors conclude. "Further large-scale studies are required to determine the longitudinal associations between the composition of intestinal microflora, antibiotic use, and atopic dermatitis during infancy, and the development of asthma in low-risk and high-risk children. In the interim, it would be prudent to avoid the unnecessary use BS (broad-spectrum) antibiotics in the first year of life when other antibiotics are available."

Mark H. Ebell, MD, MS, from Michigan State University in East Lansing, in a 2005 editorial responding to the use of antibiotics in children with lower respiratory tract infections provided the following message - "Physicians have a duty to listen carefully to patients' symptoms, to examine them carefully, and to take the time to explain their illness to them," Dr. Ebell writes. "However, physicians have no duty to fulfill patients' expectations for inappropriate care, such as prescribing antibiotics when they are not indicated, and must be mindful of the duty to the larger community that suffers financially and medically when antibiotics are overused." (2)

The message to parents is that it's important to recognize that inappropriate antibiotic use carries risks. Parental expectations from physicians can exacerbate the problem. Twenty percent of doctors were more likely to prescribe antibiotics when they perceived that parents expected it - 24% of parents question doctors when antibiotics are not prescribed for childhood respiratory infections. Seventy five precent of prescriptions were written just because parents want their children to take them.(1) Don’t be one of those parents. Most childhood respiratory infections from virus will clear up in a couple of days. Understanding the proper use of antibiotics, through open communication and physician trust, can keep your child healthier, lead to better immune function, and according to this new study, reduce your child’s risk of asthma.

(1)Arch Pediatr Adolesc Med. 2006;160:945-952.
(2) JAMA. 2005; 293:3029-3035, 3062-3064
Chest. 2007;131:1753-1759.