Which bladder instillations are more effective? DMSO vs. bupivacaine/heparin/triamcinolone: a retrospective study

Introduction and hypothesis: Bladder pain syndrome/interstitial cystitis (BPS/IC) is a chronic and debilitating condition. Our objective was to compare two different bladder instillation treatments in patients with BPS/IC: dimethyl sulfoxide with triamcinolone (DMSO) vs. bupivacaine with heparin and triamcinolone (B/H/T). Our hypothesis was that both treatments are equally effective. Methods: A retrospective cohort study of instillation-naïve patients was conducted comparing responses to either DMSO or B/H/T at our tertiary urogynecology center from 2012 to 2014. The primary outcome was patient-reported percent of overall improvement from baseline. Secondary outcomes were change in patient-reported daytime voiding frequency (hours) and change in number of nighttime voiding episodes. Variables analyzed as potential confounders included pelvic pain, cystoscopy findings, levator spasm, and fibromyalgia. The two-sided Student’s t test, chi-squared test, Poisson regression, and repeated-measure analysis of variance (ANOVA) were used for analyses. Results: One hundred and ninety-three eligible patients were identified (45 receiving DMSO, 146 receiving B/H/T). Compared with baseline, DMSO patients reported 63% improvement (p < 0.0001), increased time between daytime voids by 1.5 h (p < 0.00), and a 40% reduction in nocturia episodes (p < 0.00). B/H/T patients reported 51% improvement (p < 0.00), increased time between daytime voids by 1.4 h (p < 0.00), and an 8% reduction in nocturia episodes (p = 0.26). When comparing the two treatments, DMSO resulted in a greater percentage of overall improvement (p = 0.02) and a significant decrease in nocturia episodes when compared with B/H/T (p = 0.02). There was no significant difference between treatments for daytime voiding frequency (p = 0.50). Conclusion: Bladder instillations with DMSO or B/H/T provide overall symptomatic improvement and improved frequency and nocturia. DMSO appears to provide greater improvement in nocturia and overall.