Healthcare Utilization and Cost Burden with Switching or Cycling After Starting anti-TNFs in IBD: A Retrospective Cohort Analysis

Abstract

Objective: To compare the healthcare utilization and cost burden between patients who cycle to a different anti-TNF and patients who switch to a different mechanism of action medication within ulcerative colitis (UC) and Crohn’s disease (CD). Methods: We conducted a retrospective cohort study using Merative Marketscan claims data from January 2016 to December 2024. UC and CD patients were identified as having at least two UC or CD outpatient claims or one inpatient claim in the 6 months prior to their first anti-TNF. The index date is when the patient switches or cycles, i.e., the fill of the second drug. Primary healthcare utilization outcomes were the number of inpatient admissions, inpatient length of stay, the number of outpatient visits, and the number of emergency room visits. The primary healthcare cost outcomes were total healthcare expenditure, medical expenditure, and pharmacy/medication expenditure. Secondary outcomes consisted of non-persistence of the index biologic, defined by a 90-day gap in therapy, and corticosteroid use of greater than 60 consecutive days. Inverse probability of treatment weighting was used to adjust for potential confounding variables in the observational data. Results: In the 12-month follow-up, UC cyclers were associated with a 0.2-day increase in length of stay (95% CI -1.18, 1.57), a 0.05 decrease in hospital admissions (95% CI -0.13, 0.03), 1.18 increase in outpatient visits (95% CI -0.23, 2.58), and a 0.5 increase in ER visits (95% CI -1.01, 2.01), which were statistically nonsignificant. In CD patients, cyclers had a slightly higher mean length of stay in days (ATE 0.11; 95% CI -1.44, 1.37), number of hospital admissions (ATE 0.04; 95% CI -0.07, 0.14), and number of ER visits (ATE 0.59; 95% CI -0.7, 1.88). The mean number of outpatient visits was 0.21 lower in the cycling group compared to the switching group in CD (ATE -0.21; 95% CI -1.94, 3.69). Healthcare utilization outcomes for CD were not statistically significant. UC patients who cycled had lower mean total healthcare expenditure (ATE -13012.44; 95% CI -32105, 5101), pharmacy expenditure (ATE -2595.93; 95% CI -20764, 17397), and medical expenditure (ATE -5592.17; 95% CI -11986, 1697) compared to switchers, but were statistically nonsignificant. In CD, cycling was associated with significantly lower total healthcare expenditures (ATE -54352.72; 95% CI -67382, -39816) and significantly lower pharmacy expenditures (ATE -53136.04; 95% CI -63709, -41280). Cycling was also associated with slightly higher mean medical expenditure in CD (ATE 441.88; 95% CI -11177.9, 43943.8) but was not statistically significant. Conclusion: Overall, within IBD, cycling between anti-TNFs was not associated with consistently higher healthcare utilization than switching to a non-anti-TNF, but it was linked to lower healthcare expenditures in CD patients.