Treatment outcomes of overactive bladder with combined therapies of botulinum toxin injections and oral agents.

Objective: Treatment options for refractory overactive bladder (OAB) following behavioral modifications and oral OAB medications remain limited. Up to 33% of women fail botulinum toxin injections (Amundsen et al. Eur Urol. 74(1):66-73, 7). This study evaluates the effectiveness of combining oral OAB agents with botulinum toxin in subjects who failed botulinum toxin therapy alone.

Methods: This is a retrospective observational study. Eligible women were those who received botulinum toxin injections for OAB between 2013 and 2018 at one academic institution. Women were given the option of oral medications as add-back therapy following failed treatment with botulinum toxin alone. Treatment response was a subjective outcome, with subjects reporting being satisfied or unsatisfied. The primary outcome was the proportion of subjects who achieved satisfactory treatment response with the combination of oral OAB medications and botulinum toxin injections. A subanalysis was performed to further investigate any risk factors associated with poor response to combination treatment. Variables were analyzed using chi-squared or Fisher's exact test and Student's t-test or Mann-Whitney U when appropriate.

Results: A total of 107 charts were reviewed. Forty-five (48%) women failed botulinum toxin alone as a treatment; 26 (29%) elected to try one or more oral OAB medications. Of the 26 women who received the combination treatment, 17 (65%) reported satisfaction and 9 (35%) remained unsatisfied. Risk factors associated with treatment failure were not identified.

Conclusion: This is an initial report on adding back oral OAB meds to patients who have failed botulinum toxin injections suggesting there may be a role for add-back oral OAB medications.