title: Botulinum toxin type A injection for refractory interstitial cystitis: A randomized comparative study and predictors of treatment response.
abstract: OBJECTIVE
  To determine whether botulinum toxin type A can represent an alternative treatment option for patients with interstitial cystitis refractory to conventional therapies.
  
  
  METHODS
  This is a single-center, prospective, open labeled, randomized comparative study. Patients with refractory interstitial cystitis were randomly divided into two groups: immediate injection (group A) or 1-month delayed injection (group B) of botulinum toxin type A after allocation. The rate of treatment response (global response assessment ≥+1: slightly improved), and changes in symptom scores and frequency volume chart variables were compared between groups 1 month after allocation. Using subjects of both groups as a single cohort, predictive factors for treatment response at 1 month post-injection and the duration of response were explored.
  
  
  RESULTS
  A total of 34 patients (group A n = 18, group B n = 16) were allocated. The response rate was significantly higher in group A than group B (72.2% vs 25.0%, P = 0.01). All symptom measures showed significant improvement in group A than group B. When both groups were combined as a single cohort, the response rate was 73.5% at 1 month, 58.8% at 3 months, 38.2% at 6 months and 20.6% at 12 months. The mean duration of response was 5.4 months. Multivariate analysis showed that past exposure to hydrodistension more than three times correlated with better outcomes.
  
  
  CONCLUSIONS
  Botulinum toxin type A injection could be an alternative treatment option for patients with interstitial cystitis refractory to conventional therapies, especially for those who have received repeated hydrodistensions and transurethral fulguration.
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.|Department of Continence Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Akiyama
authors.affiliation: Department of Urology, Mitsui Memorial Hospital, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Nomiya
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Niimi
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Yamada
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Fujimura
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Nakagawa
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fukuhara
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Kume
authors.affiliation: Department of Continence Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Igawa
authors.affiliation: Department of Urology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Homma
mesh_terms: D065087:Acetylcholine Release Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D000283:Administration, Intravesical; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage* / Q000009:adverse effects; D018856:Cystitis, Interstitial / Q000188:drug therapy*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019233:Retreatment; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D065087:Acetylcholine Release Inhibitors; D019274:Botulinum Toxins, Type A
keywords: botulinum toxins type A; hydrodistension; interstitial cystitis; intravesical administration; randomized controlled trial