Associations between use of targeted therapies, hospitalizations, and emergency department visits among patients with atopic dermatitis: A retrospective cohort study

BACKGROUND: Atopic dermatitis (AD) is the most common inflammatory dermatologic condition. Despite approvals of numerous targeted therapies, no studies have examined their real-world relationship with acute health care uses and health care spending for patients with AD. OBJECTIVE: To assess the association between use of targeted therapy and the probability of hospitalizations and emergency department (ED) visits and health care spending among adult patients with AD in the United States. METHODS: This retrospective cohort study used MarketScan commercial insurance claims data from January 1, 2012, through December 31, 2023, with analyses conducted between November 1, 2023, and August 1, 2024. Adult patients (aged ≥18 years) with a diagnosis of AD who had at least 1 prescription claim for a targeted AD therapy (upadacitinib, abrocitinib, tralokinumab, baricitinib, dupilumab) were included. The primary outcomes were any hospitalizations and any ED visits in a given year. The secondary outcomes were annual total health care spending and spending by type of service (drug, inpatient, and outpatient), and patient out-of-pocket costs. A difference-in-differences (DiD) design was employed to compare changes in outcomes between patients with AD who received targeted therapies and those who did not receive a prescription for these therapies. RESULTS: Among 157,966 (mean [SD] age = 41.6 [13] years; 55,077 [35%] male) individuals with AD, 9,320 (6%) received prescriptions for a targeted therapy, among whom 99% received dupilumab. The DiD results showed that targeted-therapy use was associated with a decrease of 1.6 percentage points (95% CI = −0.021 to −0.010; P < 0.01) in the probability of any hospitalization and a decrease of 1.7 percentage points (95% CI = −0.025 to −0.008; P < 0.01) in the probability of any ED visits. Targeted therapy was associated with an increase in overall health care spending ($24,901; 95% CI = $24,482-$25,320), which was entirely due to increases in drug spending ($26,061; 95% CI = $25,735-$26,388) along with decreases in inpatient and outpatient spending. It was also associated with a $95 increase in annual patient out-of-pocket spending (95% CI = $83-$108). CONCLUSIONS: Among adults with AD, initiation of targeted therapy was associated with fewer all-cause hospitalizations and ED visits relative to nontargeted-therapy care. Targeted therapy was associated with higher total and drug spending but lower inpatient and outpatient spending.