We hypothesized that combination therapy would provide a synergistic effect to improve treatment outcomes for overactive bladder (OAB), thus enhancing the motivation for continuous exercise, and that it would be associated with fewer adverse events than monotherapy. Therefore, we investigated whether biofeedback-assisted pelvic floor muscle training (PFMT), drug therapy, or a combination of both would be more effective in improving the symptoms of OAB.

This randomized controlled trial included women diagnosed with OAB. Group 1 received biofeedback-assisted pelvic muscle floor training (PFMT) for 12 weeks; group 2 took 5 mg of solifenacin/day for 12 weeks; and group 3 received 5 mg of solifenacin/day in combination with biofeedback-assisted PFMT during the first 4 weeks and biofeedback-assisted PFMT for another 8 weeks. All participants had 5 follow-up visits. The primary outcomes were objective improvement of OAB symptoms and quality of life. The secondary outcomes were treatment-related adverse events, subjective improvement of OAB symptoms, and electromyographic activity of pelvic floor muscle (PFM) contraction.

One hundred sixty-five participants were recruited between June 2016 and December 2021. All participants reported significant improvement of OAB symptoms and quality of life. Participants in group 2 experienced more pronounced adverse events than those in group 3. Intervention duration was positively associated with subjective improvement in OAB symptoms in all groups, with significant improvements at weeks 4, 8, and 12. When week 4 was used as the reference, only group 3 showed significant improvement of OAB symptoms at week 12. Drug-related adverse events, including dry mouth, myalgia, and restlessness, had a negative impact on the subjective improvement of OAB symptoms in group 2. In group 1, exercise adherence was positively correlated with subjective improvement of OAB symptoms, whereas in group 3, PFM contraction and biofeedback effect were positively correlated with symptom improvement.

The combination therapy of 5 mg solifenacin daily for 4 weeks and biofeedback-assisted PFMT for 12 weeks is efficacious in treating women with OAB. A rapid effect and persistent clinical improvement were evident from week 2 of intervention and were associated with fewer side effects over time.
Drug-related adverse events, including dry mouth, constipation, myalgia, restlessness, and heartburn, were significantly higher in group 2 than in group 3 at weeks 2, 4, 8, and 12. Despite using the same regimen and dosing interval, participants in group 2 still exhibited significantly higher drug-related side effects than those in group 3 during the first 4 weeks of the intervention. Dry mouth may have been a contributing factor to the increased daily water intake in group 2. The uniqueness of this study is that we made between-group comparisons instead of just reporting the adverse events in each group.

Combination therapy is efficacious in treating women with OAB.