Duration of breast feeding and attention-deficit/hyperactivity disorder in United States preschool-aged children

Background: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by difficulties sustaining attention and controlling hyperactivity and impulsive behavior. Population-based studies concerning the association between breast-feeding duration and ADHD among preschool-aged children in the United States (U.S.) have been sparse. Aims: To determine whether there is an association between the duration of breast feeding and ADHD in U.S. children aged 2-5 years. Methods and procedures: We used nationally representative data from the 2016, 2017, and 2018 National Survey of Children's Health (NSCH) to examine the association between breast-feeding duration and ADHD in U.S. preschool-aged children. Sample characteristics were compared using Rao-Scott chi-square test, and adjusted prevalence odds ratios and 95 % confidence intervals were estimated using unconditional logistic regression. Outcomes and results: Of the 20,453 children eligible for our study, 1.5 % had received a diagnosis of ADHD and 77.5 % were reported to have been fed human milk as infants. Prevalence odds of ADHD were 57 % lower among children fed human milk for 6-12 months compared to children never fed human milk after controlling for potential confounders. Among children with durations of breast feeding lasting less than 6 months or lasting 12 months or longer, prevalence odds of ADHD were not significantly lower than the comparison group, children who were never fed human milk, after controlling for potential confounders. Conclusions and implications: We noted an inverse association between breast feeding durations of 6-12 months and parent-reported diagnosis of ADHD in preschool-aged children in the U.S. Future studies should use longitudinal designs to examine ADHD and duration of breast-feeding measures.