Epidemiology of Treatment for Preschoolers on Kentucky Medicaid Diagnosed with Attention-Deficit/Hyperactivity Disorder

Objectives: The National Survey of Children's Health reported a concerning increase in children 2-5 years being diagnosed with attention-deficit/hyperactivity disorder (ADHD) in 2016. Concerns include both the increase in diagnosing and potential deviations from published guidelines for the treatment of ADHD in preschoolers. The present study aims to describe the epidemiology and factors associated with receiving the diagnosis and treatment types for low-income preschoolers. Methods: Using Kentucky Medicaid claims from 2012 to 2017, a retrospective cohort study of children 2-5 years of age (n = 337,631) with a diagnosis of ADHD (n = 11,712) was completed. Trends in demographics, comorbidities, and treatment and provider types are presented. Multinomial logistic regression was used to determine predictors of receipt of the diagnosis and treatment type (a stimulant only, an alpha-2 agonist [A2A] only, both, or neither) based on nonmissing 2017 data (n = 2394). Results: The number of children in the cohort diagnosed with ADHD and receiving a stimulant decreased from 2012 to 2017, but the use of A2As increased. Primary care physicians were the most frequent prescribers of both medications. The adjusted odds ratios (AORs) of receipt of an A2A alone, stimulant alone, or both medications over receiving no ADHD medication were associated with specific demographics and comorbid conditions for each medication regimen. Race/ethnicity is associated with receiving the diagnosis of ADHD and treatment with A2A. Comorbid mental health conditions and provider type are associated with treatment type. Conclusion: Use of stimulants for preschoolers in Kentucky has decreased and A2A use has increased since 2012. Continued vigilance and long-term follow-up of preschoolers with ADHD are warranted. The appropriateness of the diagnosis and treatment type could not be determined.