A recent study (A Kloop et al. J Pediatr 2017; 190: 192-9) examined the relationship between mode of infant feeding and the development of asthma. The authors used prospective data from 3296 Canadian children in the Canadian Healthy Infant Longitudinal Development (“CHILD” study) cohort.
- “Compared with infants who received direct breast milk only [at 3 months of age], those who received some expressed milk had a 43% increased odds [of asthma at 3 years of life] …and those who received only formula had a 79% increased odds.”
The authors speculate that the direct breastfeeding may offer some advantages over expressed breast milk:
- There may be alteration in breast milk components with storage
- A nursing infant may trigger an increased immune response and be directly exposed to some beneficial commensal bacteria
Since this is an observational study and patients were not randomized there may be other unrecognized confounding variables.
Another study in the same issue (AF Beck et al. J Pediatr 2017; 190: 200-6) assessed whether the Child Opportunity Index (COI) was associated with asthma outcomes in a retrospective cohort of 5462 children in Hamilton County, Ohio. The COI (see below for the measures in this index) has previously been linked to life expectancy, low birth weight, and prematurity. Interestingly, one can go to diversitydatakids.org to see how this affects your location (here is the link for a heat map of this index in the Atlanta area: Atlanta COI)
- Median hospitalization rates varied based on COI –those with very high opportunity had a rate of 1.8 per 1000. The other quintiles of COI were the following: high opportunity 2.1, moderate opportunity 4.6, low opportunity 7.6, and very low 9.1
My take: The first study indicates that direct breastfeeding is associated with lower rates of asthma. The second study shows that issues related to education, environment, and social/poverty have an enormous impact on need for asthma-related hospitalization.