OBJECTIVES: To assess the impact of psychiatric comorbidities, specifically anxiety and depression, on healthcare resource utilization (HRU) and costs in adults with attention-deficit/hyperactivity disorder (ADHD) in the United States.

METHODS: Adults with ADHD were identified in the IQVIA PharMetrics® Plus database (10/01/2015-09/30/2021). The index date was defined as the date of initiation of a randomly selected ADHD treatment. The baseline period was defined at the 6 months prior to the index date and the study period as the 12 months following the index date. Patients with ≥1 diagnosis for anxiety and/or depression during both the baseline and study periods were classified in the ADHD+anxiety/depression cohort, while those without diagnoses for anxiety nor depression at any time were classified in the ADHD-only cohort. Entropy balancing was used to create reweighted cohorts with similar baseline characteristics. All-cause HRU and healthcare costs were assessed during the study period and compared between cohorts using regression analyses.

RESULTS: After reweighting, patients in the ADHD+anxiety/depression cohort (N=217,944) and ADHD-only cohort (N=276,906) had similar characteristics (mean age 34.1 years; 54.8% male). All-cause HRU were higher in the ADHD+ anxiety/depression cohort than the ADHD-only cohort (incidence rate ratios for inpatient admissions: 4.5, emergency room visits: 1.7, outpatient visits: 2.0, and psychotherapy visits: 6.4; all p<0.01). All-cause healthcare costs were more than twice higher in the ADHD+anxiety/depression cohort than the ADHD-only cohort (mean per-patient-per-year [PPPY]: $11,315 vs. $5,335, respectively; p<0.01). Among the ADHD+anxiety/depression cohort, average all-cause healthcare costs were $9,232, $10,650, and $15,609 PPPY among patients with anxiety only, depression only, and both anxiety and depression, respectively.

CONCLUSIONS: Comingling anxiety and depression is associated with additional HRU and costs burden in patients with ADHD. Co-management of these conditions is important and has the potential to alleviate the burden experienced by patients and the healthcare system.