Modified botulinum toxin type A injections improve symptoms associated with interstitial cystitis/bladder pain syndrome in women: a retrospective cohort study

Abstract

ObjectiveTo investigate the efficacy and safety of modified botulinum toxin type A (BoNT-A) injections (with additional periurethral injection [PUI] of BoNT-A) for the treatment of interstitial cystitis/bladder pain syndrome (IC/BPS). MethodsThis single-center, retrospective cohort study included 52 adult female patients with IC/BPS, with 24 patients receiving conventional BoNT-A injections and 28 receiving modified BoNT-A injections. The primary outcome measure was patient-reported global response assessment (GRA). Secondary outcomes included daytime frequency, nocturia, number of urinary urgency episodes in the voiding diary, pain visual analog score, O'Leary-Sant Interstitial Cystitis Symptom Index and Interstitial Cystitis Problem Index, pelvic pain and urgency/frequency scores, risk factors for recurrence, and postoperative recurrence-free time. ResultsThe median duration of follow-up was 16.0 months (interquartile range 11.75–21 months). Patients who underwent modified BoNT-A injections showed significant improvement in postoperative GRA, symptom questionnaires, and pain assessment compared with those who underwent conventional surgery. A statistically significant difference was observed between the two groups in terms of recurrence-free time (12.5 vs. 18.0 months, P=0.02). Subgroup analysis suggested that additional PUI of BoNT-A was more effective in patients with combined severe periurethral pain. No serious complications occurred in both groups, and all minor postoperative complications were temporary. ConclusionsModified BoNT-A injection is an effective treatment for IC/BPS that significantly reduces pain and improves voiding symptoms. It is particularly effective in patients with combined periurethral pain. In such patients, PUI of BoNT-A should be added to the routine intravesical injection of BoNT-A.