There are many root causes of ADHD and certainly many other causes that have not yet been identified. Have you ever considered that a common drug taken during pregnancy might be associated with ADHD? Thanks to data obtained as part of the Norwegian Patient Registry and the Norwegian Mother and Child Cohort Study, Ystrom et al. (10.1542/peds.2016-3840) have opted to explore the possibility of an association between ADHD and prenatal acetaminophen use in a study we are early releasing this week. The authors have done their best to control for possible confounders such as family history of ADHD, use of acetaminophen before becoming pregnant, and indications for acetaminophen use, but even after doing that, they discover a modest association exists if acetaminophen was used for more than 29 days during a pregnancy but not if used for less than 21 days. Paternal use before pregnancy also was found to be associated with ADHD.
So why is this? What could be responsible for this association (which is all this cross-sectional study can tell us rather than prove any semblance of causality)? To answer that we asked behavioral and developmental pediatrician Dr. Mark Wolraich to share his opinion in an accompanying editorial (10.1542/peds.2017-2703). He speaks to the benefits of using large data sets such as those used in this study to establish these interesting associations but also to the need for large prospective longitudinal studies to further determine what if any causal role exists for prenatal use of acetaminophen in the pathogenesis of ADHD. This study and commentary are both well worth your attention!
