Breastfeeding and the Risk of Attention Deficit Hyperactivity Disorder in Children
by Anne Eglash MD, IBCLC, FABM
There is significant evidence that children who are breastfed have fewer behavioral problems, even into adolescence. It is unclear if attention deficit underlies some of these behavioral problems. Children with attention deficit hyperactivity disorder are not often diagnosed until they are older, often over age 5, yet can be difficult preschoolers, due to impulsivity.
The authors of this week’s article used survey data from the Centers for Disease Control and Prevention’s 2011/12 National Survey of Children’s Health, to estimate the association between breastfeeding duration, timing of formula initiation and diagnosis of ADHD in children aged 3-5 years. The parents were asked details on the duration of breastfeeding, timing of formula supplementation, and whether their child was ever diagnosed with ADHD or ADD by a health care provider.
Children with a variety of physical and neurological disorders were excluded. The study controlled for several factors that may play a role in infant feeding and ADD/ADHD including sex, race, household income, exposure to secondhand smoke and prematurity.
There were 12,793 participants aged 3-5 years in the study, and 77% ever breastfed. Thirty percent exclusively breastfed for 6 months, and 23% of all children were exclusively formula fed.
Within this population 98 participants had a diagnosis of ADHD. Among those with ADHD, 62% ever breastfed, and 11% exclusively breastfed for 6 months. The authors concluded that longer breastfeeding was associated with a decreased risk of ADHD.
- For every additional month of breastfeeding, the odds of ADHD were reduced by 8%.
- Children who breastfed exclusively for 6 months had lower odds of ADHD compared with those who didn’t breastfeed exclusively but breastfed longer.
- The age when formula was introduced was not associated with the risk of ADHD.
See the Answer
Breastfeeding has been associated with a lower risk of attention-deficit/hyperactivity disorder (ADHD). However, most studies examining this association have focused on small samples outside the United States or were likely subject to substantial residual confounding.
To investigate, in a nationally representative sample of preschool children in the United States, the associations between ADHD and both age of breastfeeding cessation and age of formula introduction, as well as associations between ADHD and exclusive breastfeeding duration.
Analysis of data from children aged 3 to 5 years in the 2011/12 National Survey of Children’s Health (n 5 12,793). Logistic regressions were used to model current medical diagnosis of preschool ADHD as a function of breastfeeding duration, breastfeeding exclusivity, and the timing of formula introduction with adjustment for 12 potential confounders using propensity scores, including sex, age, race, household income, prematurity, insurance, and medical home.
After adjustment for potential confounders, exclusive breastfeeding for at least 6 months was associated with substantially reduced odds of ADHD (adjusted prevalence odds ratio [aPOR] 5 0.38; 95% confidence interval [CI], 0.15–0.99). Breastfeeding duration was also associated with ADHD, with 8% reduced odds of ADHD for each additional month of breastfeeding (aPOR 5 0.92; 95%CI, 0.86–0.99). The results for exclusive breastfeeding duration were similar, but the confidence interval included the null (aPOR 5 0.92; 95% CI, 0.85–1.00). The age of formula introduction was not associated with ADHD (aPOR 5 0.92; 95% CI, 0.81–1.05).
In a nationally representative sample of preschool children, breastfeeding was associated with a lower prevalence of ADHD. These findings provide evidence in support of the neurodevelopmental benefits of breastfeeding.
The authors of this study offer a few hypotheses for their findings, including the presence of certain hormones in breastmilk that are not in formula, the increased maternal contact during breastfeeding, and the possible increased risk of bisphenol A exposure in the formula fed subjects. Bisphenol A, banned from infant food packaging in July 2013 by the US Food and Drug Administration, has been associated with the risk of hyperactivity.
My question is whether breastfeeding would mitigate the risk of ADHD among infants born to a parent with ADHD. Attention deficit/hyperactivity disorder has a heritability rate of ~74%, which means that the greatest risk for having ADHD is genetic/family history. If so, then we could counsel parents with known ADHD that breastfeeding exclusively would help to reduce their children’s risk.