A Study of the Association Between Obesity/Overweight Status and Attention Deficit Hyperactivity Disorder in a Pediatric Population
Dr. Melissa Holland
Purpose
Attention deficit hyperactivity disorder (ADHD) is a common behavioral disorder for children and adolescents. Recent studies suggest that there may be a comorbidity between ADHD and overweight status and obesity in school aged children. Despite the rise in obesity and overweight status among children as well as the increase in diagnoses of ADHD, there have been no recent studies in the United States investigating an association between the two conditions. This study examined whether an association exists between the diagnosis of ADHD and weight status in children using the National Ambulatory Medical Care Survey (NAMCS) for the years 2006-2010.
Methods
This was a retrospective, cross-sectional, observational study of children and adolescents age 5 to 17 who participated in NAMCS for any of the years studied. Exclusion criteria included below normal weight and certain confounding comorbidities. This study used de-identified data from a publicly available dataset created by the Centers for Disease Control and Prevention, therefore the study was IRB-exempt. Chi-square tests were used to evaluate the association of weight status using body mass index (BMI) percentiles and diagnosis of ADHD. The secondary analysis also utilized chi-square tests to evaluate the association between predictors of interest and weight status in children with a diagnosis of ADHD. Pairwise comparisons were done for all variables with more than two levels that were found to be significant (p-value less than 0.05). Predictors with a p-value less than 0.2 were included in a multivariate logistic regression model to assess their joint predictive ability. Odds ratios and 95 percent confidence intervals were reported. The tertiary analysis evaluated the difference in mean BMI percentiles utilizing a t-test to compare those with ADHD diagnosis (Yes vs. No). Due to the NAMCS sampling methodology, all analyses were weighted and clustered as appropriate to allow for extrapolation to population-based estimates.
Results
There were 5,938 participants included in the analysis. Weight status (normal vs. overweight vs. obese) was found to be associated with the diagnosis of ADHD (p-value equals 0.0037). Those diagnosed with ADHD were found to be 37 percent less likely to be overweight (OR 0.63, 95 percent CI 0.45-0.88) and 30 percent less likely to be obese (OR 0.70, 95 percent CI 0.52-0.94). Ethnicity was found to be associated with weight status (p-value equals 0.0113). Hispanics diagnosed with ADHD were 3.36 times as likely to be obese (OR 3.36, 95 percent CI 1.40-8.07). For the tertiary analysis, the mean BMI percentile was significantly different between those diagnosed with ADHD and those with no such diagnosis (mean difference equals 5.64, p-value equals 0.0014).
Conclusion
Consistent with previous research, our study found that approximately 20 percent of children are either overweight or obese. The prevalence of overweight or obese status was higher in those with no diagnosis of ADHD. Additionally, Hispanics diagnosed with ADHD were more likely to be overweight or obese.
