Impact of New Medications and $4 Generic Programs on Overactive Bladder Treatment Among Older Adults in the United States, 2000-2015

Despite several new medications being Food and Drug Administration-approved for overactive bladder (OAB) and new prescription drug payment programs, there are limited population-based data regarding OAB medication use among older adults.

To examine: (1) impacts of new medications and $4 generic programs on time trends for OAB-related medication dispensing for older adults in the United States; (2) differences by age and sex; and (3) temporal changes in OAB-related medication payments.

Using Truven Health Analytics' Medicare Supplemental Database (2000-2015), we analyzed OAB-related medication claims for 9,477,061 Medigap beneficiaries age 65-104. We estimated dispensing rates (per 1000 person-months), assessed dispensing trends using interrupted time-series methods, compared dispensing rates by age and sex, and summarized payment trends.

From 2000 to 2015, 771,609 individuals filled 13,863,998 OAB-related prescriptions. During 2000-2007, 3 new extended-release medications became available (tolterodine, darifenacin, solifenacin), leading to increases in overall OAB-related dispensing rates by 19.1 (99% confidence interval, 17.0-21.2), a 92% increase since 2000; overall rates remained stable during 2008-2015. By 2015, the most common medications were oxybutynin (38%), solifenacin (20%), tolterodine (19%), and mirabegron (12%). Dispensing rates peaked at age 90 (rate, 53.4; 99% confidence interval, 53.1-53.7). Women had higher rates than men at all ages (average ratewomen-ratemen, 22.0). The gap between upper and lower percentiles of medication payments widened between 2008-2015; by 2015, 25% of reimbursed dispensed prescriptions had total payments exceeding $250.

Medication-specific dispensing rates for OAB changed when new alternatives became available. Recent changes in utilization and cost of OAB medications have implications for clinical guidelines, pharmacoepidemiologic studies, and payment policies.

Medical care. 2017 Dec 28 [Epub ahead of print]

Alan C Kinlaw, Michele Jonsson Funk, Mitchell M Conover, Virginia Pate, Alayne D Markland, Jennifer M Wu

Cecil G. Sheps Center for Health Services Research., Department of Epidemiology, School of Public Health., Birmingham/Atlanta Veterans Affairs, Geriatric Research Education and Clinical Center., Center for Women's Health Research, University of North Carolina at Chapel Hill, Chapel Hill, NC.