Infants who experience bronchiolitis during respiratory syncytial virus season within their first 6 months of life are more likely to have otitis media, pneumonia and use antibiotics regardless of their mother’s asthma status, according to a study presented at the annual meeting of the American Academy of Allergy, Asthma & Immunology in Orlando.
“The risk of developing bronchiolitis depends on multiple genetic and environmental factors,” Andrew Abreo, MD, a clinical fellow in allergy, pulmonary and critical care medicine in the Vanderbilt University Medical Center, told Infectious Diseases in Children. “Previous studies showed that maternal asthma during pregnancy increased the risk of infant bronchiolitis. We found that although infant RSV bronchiolitis increased the risk of subsequent otitis media, pneumonia and antibiotic use, there were no differences in these conditions among infants born to mothers with and without asthma.”
To examine whether infants who have experienced RSV are more prone to otitis media, pneumonia and antibiotic use, and if their mothers are more likely to have an asthma diagnosis, the researchers conducted a population-based retrospective cohort study that included healthy infants enrolled in the Tennessee Medicaid Program between 1995 and 2008.
Exposed cases were defined as diagnoses of bronchiolitis (ICD codes 466.1 and 480.1) during the winter virus season within an infant’s first 6 months. The researchers also collected data on otitis media, pneumonia and/or any antimicrobial use between 6 and 12 months of age. Information was later divided based on maternal asthma diagnosis.
Of the 252,738 healthy infants enrolled in the Tennessee Medicaid Program, 52,048 were diagnosed with bronchiolitis within their first 6 months. Those who were diagnosed with bronchiolitis were more likely to have ever experienced otitis media (605.8 per 1,000 vs. 444.5 per 1,000; 36% increase) or pneumonia (79.4 per 1,000 vs. 25.9 per 1,000; 207% increase). These infants were also more likely to have ever used antibiotics (adjusted OR = 2.16; 95% CI, 2.12-2.21).
Abreo and colleagues observed no connection between the mothers’ asthma diagnosis and their offspring’s bronchiolitis diagnosis regarding any outcome.
“RSV is the most common cause of significant infant illness and has been linked to the development of wheezing,” Abreo said. “Current RSV prevention strategies include decreasing exposure to RSV, avoidance of tobacco smoke exposure, birth timing and RSV prophylaxis in high-risk infants. These findings suggest that preventing early-life RSV bronchiolitis could prevent not just infant wheezing but also later infant infections.” – by Katherine Bortz
Abreo A, et al. Abstract 28. Presented at: American Academy of Allergy, Asthma & Immunology Annual Meeting; March 2-5, 2017; Orlando.
Disclosure: Infectious Diseases in Children was unable to confirm relevant financial disclosures prior to publication.