This study, conducted by lead author Dr. Nancy Abarca, Brown University School of Public Health MPH ‘15, sought to investigate if duration of supplemental breastfeeding is associated with a lower asthma risk and whether adverse childhood experiences (ACEs) early in life influence this relationship in children ages 3 to 5 years.
[Photo: Dr. Nancy Abarca]
Data were collected from the 2011 – 2012 National Survey of Children’s Health, a nationally representative cross-sectional survey. Modified Poisson regression models were used to estimate incident risk ratios (IRR) for lifetime and current asthma in young children aged 3 to 5 years (n = 15,642). The study tested for effect measure modification using stratified analyses.
Results indicated that exclusive breastfeeding for at least 6 months or supplemental breastfeeding for children 12 months significantly reduced the risk of lifetime asthma prevalence compared to never breastfed children (IRR 0.64; 95 percent CI: 0.46–0.88, p=0.007; and IRR 0.68; 95 percent CI: 0.47–0.99, p=0.044, respectively), adjusted for covariates. In stratified analyses, breastfeeding reduced the risk of lifetime asthma for children who experienced 1 ACE but not for children who experienced two or more ACEs.
This study concluded that exclusive breastfeeding for at least six months, with and without supplementation, appears to prevent asthma or delay its onset. The protective effect of breastfeeding was attenuated among children who experienced more than two ACEs. The known harmful effects that ACEs have on children’s health may outweigh the benefits of breastfeeding in reducing the risk of a child developing asthma. Understanding how specific time periods in a child’s life may be most affected by exposure to early life adversities, along with the protective effect of breastfeeding against asthma, are important areas of further study.
This study was published in The Journal of Asthma in March.