Better adherence with drug treatment in children with attention-deficit/hyperactivity disorder (ADHD) may be associated with lower risk for oppositional defiant disorder or conduct disorder in adulthood, according to the results of a study published in the Journal of Clinical Psychiatry.
Researchers identified children age 4 to 18 years, newly diagnosed with ADHD, and treated with pharmacotherapy for a minimum of 90 days from Taiwan’s National Health Insurance Research Database (N=33,835). The children were followed for nearly a decade or until a diagnosis of oppositional defiant disorder or conduct disorder was established. Methylphenidate and atomoxetine were the ADHD treatments used in the study. Participants were considered medication compliant if they had a medication possession ratio of 50% or greater.
After statistical analysis, researchers found that children who were compliant with drug therapy had a significantly lower risk for the development of oppositional defiant disorder (odds ratio 0.47; 95% CI, 0.41-0.55; P <.001) or conduct disorder (odds ratio 0.42; 95% CI, 0.36-0.48; P <.001) than those who were noncompliant. In addition, participants with a medication possession ratio of 75% or more experienced the greatest degree of risk reduction.
Primary study limitations included the use of reimbursement data and the presence of confounding variables.
“In conclusion, this study finds that, among patients with ADHD receiving medication treatment, those with better drug adherence had a decreased risk [for oppositional defiant disorder or conduct disorder] developing in comparison with their counterparts with worse drug adherence,” the researchers wrote.
Further studies are needed to fully establish the link between medication adherence and the development of oppositional defiant disorder or conduct disorder.
Wang L-J, Lee S-Y, Chou M-C, Yang K-C, Lee T-L, Shyu Y-C. Impact of drug adherence on oppositional defiant disorder and conduct disorder among patients with attention-deficit/hyperactivity disorder. J Clin Psychiatry. 2018;79(5).