Recurrence of female overactive bladder syndrome (OAB) is not uncommon. It should be important to decrease the recurrence of female OAB. However, factor predicting recurrence of female OAB, especially for those women who need re-treatment, is undetermined. Thus, the aim of this study was to elucidate factors predicting re-treatment of female OAB.

The medical records, including pad testing, urodynamic studies, lower urinary tract symptoms related questionnaires and bladder diaries of all consecutive women with OAB, who visited urogynecologic clinics in a tertiary referral center, were reviewed. 
Persistence interval was defined from the date of prescription of mirabegron to the date of discontinuation of mirabegron treatment. Statistical analysis was performed with Kaplan-Meier estimator. Multivariable Cox proportional-hazard model with all variables with p <0.25 in the univariate analysis was performed to predict OAB re-treatment probability.

Between January 2015 and July 2019, a total of 120 women received mirabegron 25 mg per day for their OAB. Probability of re-treatment for their recurrence of overactive bladder symptoms was shown in Fig 1A. Twelve (10%) women were found to have OAB re-treatment. Median re-treatment-free probabilities was 154.1 weeks, 95% confidence interval = 111.3 to – weeks. Multivariable backward stepwise Cox proportional-hazard modelling by using all variables with p <0.25 in the univariate analysis revealed that persistence interval was the sole predictor for OAB retreatment (hazard ratio = 0.882, 95% confidence interval = 0.778 to 0.999, p = 0.048, Table 1).  
      The persistence interval ≥13 weeks was determined to be the optimum cut-off value to predict free of OAB re-treatment probabilities using receiver operating characteristic (ROC) analysis, which provided an area under the ROC curve of 0.62 (95% confidence interval = 0.48 to 0.75; sensitivity = 58.3%, specificity = 83.3%, Fig 1B).

Baseline pad testing, urodynamic studies, lower urinary tract symptoms related questionnaires and bladder diaries were failed to predict re-treatment of OAB. Persistence interval was the only one predictor for the re-treatment of OAB. Women who received mirabegron longer, especially for more than 13 weeks, seem to be associated with a decrease in the re-treatment probabilities of OAB. Thus, it seems reasonable that the persistence interval of OAB treatment in many clinical studies was 3 months.

Persistence interval was found to be associated with re-treatment of OAB. Women who received mirabegron longer, especially those with at least 13 weeks treatment, seem to be associated with a decrease in re-treatment probabilities of OAB. The above data may provide a guide for the treatment of female OAB with mirabegron.