Primary Nonadherence to Overactive Bladder Medications in an Integrated Managed Care Health Care System

Treatment for overactive bladder (OAB) remains suboptimal, in part because of patient nonadherence to medications. Primary nonadherence is when patients fail to pick up their initial prescriptions.

To measure primary nonadherence to OAB medications within 30 days of a first OAB prescription order using electronic medical records from a U.S. managed care health care system METHODS: A retrospective cohort study was conducted using electronic medical records from the Kaiser Permanente Southern California (KPSC) database to identify patients with new OAB prescriptions between January 1, 2007, and December 31, 2013. The index date was defined as the first order of an OAB prescription. Patients had to be aged ≥ 18 years on the index date and were required to have 12 months of continuous membership with drug benefit eligibility before, during, and after the index date. Patients were defined as primary nonadherent if they did not pick up their new OAB prescriptions within 30 days of the order date. Descriptive statistics and a multivariable logistic regression analysis with backward selection were conducted to identify factors associated with patients who were primary nonadherent versus adherent.

There were 9,050 patients with a new OAB prescription order; 1,662 (18%) of these were primary nonadherent. Patients with primary nonadherence were younger in age (56.9 [SD ± 16.0] years vs. 63.9 [SD ± 14.8] years; P < 0.001) and more likely to have commercial insurance (65.9% vs. 46.2%; P < 0.001). They also had lower mean Charlson Comorbidity Index (CCI) scores (1.99 vs. 2.70; P < 0.001), fewer OAB-related comorbidities, fewer concomitant medications (P < 0.005), and fewer overall prescriptions dispensed in the previous 12 months (P < 0.001) compared with adherent patients. Significant factors such as commercial insurance (P = 0.013), race other than white (P = 0.020), CCI = 0 versus CCI ≥ 2 (P = 0.001), urinary tract infections (P < 0.001), and falls (P = 0.047) were associated with a higher likelihood of primary nonadherence versus adherence.

Nearly 1 in 5 patients did not pick up their new OAB medications within 30 days of the order date. Knowledge of factors associated with primary nonadherence may inform strategies for improving management of OAB.

This study was supported by a research grant provided by Astellas Pharma Global Development. Rashid and Lin do not have any financial interests or potential conflict of interest with regard to the work. Vassilakis, Kristy, and Ng were employees of Astellas Pharma Global Development when this study was conducted. Study concept and design were contributed by Rashid and Ng, along with the other authors. Rashid and Lin collected the data, and data interpretation was performed by Rashid, Ng, and Lin, along with Vassilakis and Kristy. The manuscript was written by Rashid and Ng, along with Vassilakis and Lin, and revised by Rashid, Ng, and Lin.