Predictors of discontinuing overactive bladder medications.

OBJECTIVE: To identify predictors of self-reported discontinuation of overactive bladder (OAB) medication using a three-phase survey. PATIENTS AND METHODS: In January 2005, a phase 1 survey was sent to 260 000 households in the USA to assess the prevalence of OAB symptom bother, treatment patterns and healthcare consulting behaviour. In July 2005, a detailed phase 2 follow-up survey was sent to 6577 phase 1 respondents who had used one or more OAB medications within the 12 months before phase 1; the phase 2 survey included questions about respondents' sociodemographic characteristics, general health status, OAB symptom bother, healthcare consulting behaviour, beliefs about OAB and treatment options, and medication usage. Six months later, a phase 3 survey was sent to 3387 phase-2 respondents who were persistent with OAB medication or had discontinued within <18 months of phase 2; the phase 3 survey measured the same variables as phase 2. Only phase 3 respondents who were persistent with OAB medication at phase 2 were included in the analyses reported here. Assessed were the proportions of respondents who were still persistent with OAB medication at phase 3 and who discontinued OAB medication between phases 2 and 3. The variables measured during the phase 2 survey were screened as potential predictors of discontinuation at phase 3 using univariate analysis and then assessed using multivariate logistic regression.
RESULTS: Among 2838 respondents at phase 3 (84% response rate), 1194 had recently discontinued and 1644 were persistent with medication at phase 2. Among phase-3 respondents who were persistent at phase 2, 1040 (66%) continued to be persistent at phase 3, 280 (18%) had discontinued between phases 2 and 3, and 261 (17%) had switched medication between phases 2 and 3; 63 respondents had missing prescription information at phase 3. Predictors of discontinuing at phase 3 included smoking (odds ratio 1.80; 95% confidence interval 1.15-2.83; P = 0.010), not knowing whether treating bladder problems requires multiple daily doses of medication (1.71, 1.10-2.67; P = 0.018), believing (2.11, 1.34-3.33; P = 0.001) or not knowing (1.76, 1.23-2.52; P = 0.002) whether adverse effects of OAB medications are often severe, and being bothered 'quite a bit or more' by a sudden urge to urinate (1.54, 1.05-2.26; P = 0.028). Respondents taking two or more medications were less likely to discontinue (odds ratio 0.45-0.58; P < 0.05).
CONCLUSION: Persistence with OAB medications might be improved by addressing predictors of discontinuation in the management of OAB, by proactively informing patients about the severity of antimuscarinic adverse effects, and dosing regimens. Bother associated with the key OAB symptom, urgency, is a predictor of discontinuation of treatment.