• Science Update
The long-term academic problems that children with attention deficit hyperactivity disorder (ADHD) often experience may affect their siblings as well, according to an analysis partially funded by NIMH and published in the Journal of Health Economics.
Jason Fletcher, Ph.D., of Yale University and Barbara Wolfe, Ph.D., of the University of Wisconsin-Madison explored how having ADHD or having a sibling with ADHD affects a person’s short- and long-term education outcomes. Using data from the National Longitudinal Study of Adolescent Health—a school-based study of health-related behaviors of teens and their outcomes in young adulthood—Fletcher and Wolfe confirmed findings from a previous study that found ADHD affected the short-term educational achievements of children with ADHD. These children are more likely to repeat a grade and receive special education services, have lower grade point averages, experience more suspensions and expulsions, and complete fewer years of school than children without ADHD.
The researchers then explored how ADHD may impact the family, and whether the siblings of children with ADHD are affected academically by their brother’s or sister’s ADHD symptoms.
Results of the Study
Results did not initially indicate that ADHD had long-term negative influences on children. Rather, it appears that the academic performances of both the ADHD child and his or her siblings even out over the long term. But by using economic modeling techniques, Fletcher and Wolfe concluded that having a sibling with ADHD may indeed impact the academic productivity of a sibling without the disorder. They theorize that the ADHD child, who can be more disruptive, may receive more attention from parents, which may cause the academic performance of the non-ADHD sibling to suffer. The researchers suggest that other studies may underestimate the academic consequences of ADHD among other family members.
The study reveals potential evidence that having a sibling with ADHD can be harmful to one’s educational outcomes. The study’s conclusions may help illustrate why there seems to be few long-term differences in academic achievements between a child with ADHD and his or her siblings.
The conclusions of the study strongly suggest that the consequences of ADHD extend beyond those that directly affect the child with ADHD. More controlled studies are necessary to verify this conclusion. In the meantime, the researchers propose that additional school resources be focused on those with ADHD and their families.
Fletcher J and Wolfe B. Child mental health and human capital accumulation: The case of ADHD revisited . Journal of Health Economics. 2008 May; 27(3): 794-800.