Objectives: To compare the healthcare costs of patients with overactive bladder (OAB) who switch vs persist on anti-muscarinic agents (AMs), describe resource use and costs among OAB patients who discontinue AMs, and assess factors associated with persisting vs switching or discontinuing.
Methods: OAB patients initiating an AM between January 1, 2007 and March 31, 2012 were identified from a claims database of US privately insured beneficiaries (n ≈ 16 million) and required to have no AM claims in the 12 months before AM initiation (baseline period). Patients were classified as persisters, switchers, or discontinuers, and assigned a study index date based on their AM use in the 6 months following initiation. Baseline characteristics, resource use, and costs were compared between persisters and the other groups. Resource use and costs in the 1 month before and 6 months after the study index date (for switchers, the date of index AM switching; for persisters, a randomly assigned date to reflect the distribution of the time from AM initiation to switching among switchers) were also compared between persisters and switchers in unadjusted and adjusted analyses. Factors associated with persisting vs switching or discontinuing were assessed.
Results: After controlling for baseline characteristics and costs, persisters vs switchers had significantly lower all-cause and OAB-related costs in both the month before (all-cause $1222 vs $1759, OAB-related $142 vs $170) and 6 months after the study index date (all-cause $7017 vs $8806, OAB-related $642 vs $797). Factors associated with switching or discontinuing vs persisting included index AM, younger age, and history of UTI.
Conclusion: A large proportion of OAB patients discontinue or switch AMs shortly after initiation, and switching is associated with higher costs.
Keywords: Adherence; Anti-muscarinic agents; Claims data; Costs; Healthcare resource use; Overactive bladder; Persistence; Switching; Treatment patterns.