Time to Initiation of Pentosan Polysulfate Sodium Treatment After Interstitial Cystitis Diagnosis: Effect on Symptom Improvement

ObjectivesInterstitial cystitis (IC) is a chronic, debilitating condition that is often associated with late diagnosis and a delay in initiation of appropriate IC-specific therapy. The purpose of this study was to determine whether the length of time from initial diagnosis to start of treatment impacts subsequent symptom improvement.MethodsA retrospective analysis was conducted in 128 patients with IC who had been treated with pentosan polysulfate sodium (PPS) 300 mg/day for 32 weeks in a multicenter, randomized, double-blind, parallel-group clinical trial. Outcome measures included the O’Leary-Sant Interstitial Cystitis Symptom Index (ICSI) and the O’Leary-Sant Interstitial Cystitis Problem Index (ICPI). Early treatment was defined as treatment initiation 6 months or less after IC diagnosis, whereas late treatment was defined as treatment initiation 24 months or more after IC diagnosis. Efficacy data were analyzed by using the intent-to-treat, last-observation-carried-forward population.ResultsAt the end of the study, mean changes from baseline in total ICSI and ICPI scores (± SEM) for early treatment (6 months or less) versus late treatment (24 months or more) were 3.97 ± 0.59 versus 2.15 ± 0.70 (P = 0.0472) and 3.94 ± 0.56 versus 1.77 ± 0.63 (P = 0.0117), respectively. Similar trends for both measures were observed when examining other times from IC diagnosis (3 months or less versus 24 months or more, 3 months or less versus 36 months or more, and 6 months or less versus 36 months or more).ConclusionsInitiation of PPS treatment within 6 months of establishing the diagnosis of IC may be associated with greater improvement in patient symptoms and symptom bother.