Introduction

Overactive bladder (OAB) is a syndrome characterized by urinary urgency, increased daytime frequency, and nocturia, excluding infections and localized pathology. Its prevalence increases with age. Many patients hesitate to seek help due to embarrassment. Risk factors include irritable bowel syndrome, obesity, and certain gender-specific issues like prostate disease in men and uterine prolapse in women. Diagnosis requires ruling out infection or stress incontinence. Individuals with OAB often experience diminished quality of life and increased anxiety. Until recently, treatment mainly involved antimuscarinics, but beta-3 agonists like Mirabegron and Vibegron are now available in some countries, expanding therapeutic options.

Aim

To assess the efficacy of mirabegron versus other treatments for OAB using current evidence and comparing the results of this systematic review (SR) with those of other SRs.

Method

Study Design

• Systematic review of randomized clinical trials (RCTs)

Treatment Strategy

• This systematic review was conducted in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, following the standards outlined in the Cochrane Handbook for Systematic Reviews of Interventions.

  Results

• This systematic review included 28 RCTs (n = 27,481 adults)
• Twelve studies compared mirabegron with placebo, and 6 RCTs assessed mirabegron 50 mg vs 25 mg
• Mirabegron was evaluated against imidafenacin in 2 studies, tolterodine in 6 studies and solifenacin in 7 RCTs, 1 study compared mirabegron with oxybutynin and 5 studies analysed the combination of mirabegron and solifenacin
• Mirabegron vs Placebo
  • Significant improvement in the number of micturition/24 h (MD -0.24), number of urgency episodes/24 h (MD -0.62), urge urinary incontinence (UI) episodes/24 h (MD -0.41), nocturia episodes/24 h (MD -0.10) and total incontinence episodes (MD -0.47) were seen with mirabegron 25 mg vs placebo within 3 months of treatment
  • Notable improvements were demonstrated by mirabegron 50 mg vs placebo in micturition/24 h (MD -0.53), urgency episodes/24 h (MD -0.49), urgency UI episodes/24 h (MD -0.44), nocturia episodes/24 h (MD -0.18) and total incontinence episodes/24 h (MD -0.44)
• Mirabegron vs Imidafenacin
  • The incidence of adverse events (AEs) was significantly lower with mirabegron 50 mg
  • However, the differences in micturitions, UUI and total incontinence were insignificant
• Mirabegron vs Tolterodine 4 mg
  • The findings favored mirabegron 50 mg with respect to micturitions (MD -0.16) and overall AEs (OR 0.71)
• Mirabegron 50 mg vs Solifenacin 5 mg
  • Solifenacin 5 mg remarkably increased volume/micturition (MD -7.77)
• Mirabegron 50 mg vs Oxybutynin 73.5 mg
  • Mirabegron 50 mg reduced the overall AEs (OR 0.02)
• Mirabegron plus Solifenacin vs Solifenacin
  • The outcomes were significantly better with mirabegron 50 mg combined with solifenacin 5 mg

Conclusion

• The findings of this systematic review concluded that mirabegron is an effective, safe, and well-tolerated treatment for overactive bladder (OAB) symptoms.
• Additionally, the combination of mirabegron with anticholinergics offers a beneficial additive effect without an increased risk of side effects.

Eur Urol Focus. 2024 Sep 28:S2405-4569(24)00181-0. Doi: 10.1016/j.euf.2024.09.012.