Medical Expenditures Associated with Attention-Deficit/Hyperactivity Disorder Among Adults in the United States by Age, 2015-2019.

BACKGROUND: Attention-deficit hyperactivity disorder is a common disorder that affects both children and adults. However, for adults, little is known about ADHD-attributable medical expenditures. OBJECTIVE: To estimate the medical expenditures associated with ADHD, stratified by age, in the US adult population. DESIGN: Using a two-part model, we analyzed data from Medical Expenditure Panel Survey for 2015 to 2019. The first part of the model predicts the probability that individuals incurred any medical costs during the calendar year using a logit model. The second part of the model estimates the medical expenditures for individuals who incurred any medical expenses in the calendar year using a generalized linear model. Covariates included age, sex, race/ethnicity, geographic region, Charlson comorbidity index, insurance, asthma, anxiety, and mood disorders. PARTICIPANTS: Adults (18 +) who participated in the Medical Expenditure Panel Survey from 2015 to 2019 (N = 83,776). MAIN MEASURES: Overall and service specific direct ADHD-attributable medical expenditures. KEY RESULTS: A total of 1206 participants (1.44%) were classified as having ADHD. The estimated incremental costs of ADHD in adults were $2591.06 per person, amounting to $8.29 billion nationally. Significant adjusted incremental costs were prescription medication ($1347.06; 95% CI: $990.69-$1625.93), which accounted for the largest portion of total costs, and office-based visits ($724.86; 95% CI: $177.75-$1528.62). The adjusted incremental costs for outpatient visits, inpatient visits, emergency room visits, and home health visits were not significantly different. Among older adults (31 +), the incremental cost of ADHD was $2623.48, while in young adults (18-30), the incremental cost was $1856.66. CONCLUSIONS: The average medical expenditures for adults with ADHD in the US were substantially higher than those without ADHD and the incremental costs were higher in older adults (31 +) than younger adults (18-30). Future research is needed to understand the increasing trend in ADHD attributable cost.