Persistence and Adherence of Medications for Chronic Overactive Bladder/Urinary Incontinence in the California Medicaid Program

Abstract

For chronic OAB/UI patients identified in this study, both persistence and adherence with medication treatment were suboptimal. These results suggest that persistence and treatment discontinuation remains problematic for the OAB/UI population.

Persistence of antimuscarinic drug use

“…Discussion Surprisingly, we found much higher persistence rates than previously reported in the literature, with our 1-year persistence rates comparable to the 30-day persistence rates found by others [10,11,14]. The health-care setting with easy access and generous reimbursements might also explain the higher persistence.…”

“…Other studies have shown better continuation rates with once-daily dosing [10,11]. We failed to replicate this finding in the present study, as trospium chloride, prescribed twice daily on an empty stomach, had much better continuation rates than, e.g., tolterodine or solifenacin, which are prescribed without these caveats.…”

“…Most patients entered in our study had probably paid for their first prescription themselves, thus likely excluding those reluctant to pay anything at all. Looking at the Kaplan-Meier estimates in the studies by Yu et al and Shaya et al, we are somewhat surprised by the large number redeeming only one prescription [10,11]. This finding might be explained by the lack of patient incentive to continue an expensive treatment.…”

“…Our choice of allowing a 120-day gap in treatment episodes could also have contributed to the particularly high persistence found in our study. Other studies have allowed smaller gaps [10,11,14].…”

“…However, the external validity of these findings has been questioned by the somewhat more somber findings of real-life prescription refill behavior. In a California Medicaid population, Yu et al found 1-year continuation rates of only 12% [10]. In a younger Medicaid managed-care population, Shaya et al found even lower estimates, with only 44% of patients refilling their prescription for tolterodine extended-release after 30 days, and with a 1-year continuation rate of only 9% [11].…”