Associations between comorbidities and bladder conditions in patients with interstitial cystitis/bladder pain syndrome

Abstract Purpose To examine the associations among functional somatic disorders, psychiatric disorders, medical diseases, and extravesical inflammatory disorders with bladder conditions in patients diagnosed with interstitial cystitis/bladder pain syndrome (IC/BPS). Methods Patients with confirmed IC/BPS were included in this retrospective analysis. Cystoscopic hydrodistention was performed to identify the presence of Hunner’s (HIC) and non-Hunner’s IC (NHIC) and classify the bladder condition according to maximal bladder capacity (MBC) and glomerulation grade. Treatment outcomes were assessed using the Global Response Assessment scale (GRA). Data on the comorbidities of patients were obtained from chart reviews and classified as functional somatic disorders, psychiatric disorders, autoimmune diseases, or medical diseases. Fifteen urinary biomarkers were examined, including inflammatory proteins, neurogenic proteins, and oxidative stress biomarkers. The associations between bladder condition and urinary biomarker levels were compared between patients with and without comorbidities. Results Overall, 389 patients with IC/BPS, including 44 HIC and 345 NHIC, were enrolled in this study. Among the patients, 324 (83.3%) had various comorbidities, while 65 (16.7%) did not. Patients with depression had higher rate of glomerulation grade 2 or 3 and MBC < 760 mL, while patients with insomnia and arrhythmia had higher rate of glomerulation grade 0 or 1 and MBC ≥ 760 mL. Urinary levels of the inflammatory urinary biomarker RANTES and oxidative stress biomarker 8-OHdG were significantly lower in patients with IC/BPS with functional somatic and psychiatric disorders. The other biomarkers did not differ significantly between subgroups. Patients with and without comorbidities had similar GRA scores after long-term treatment (56% vs 56.9%, p = 0.896). Patients with comorbid IC/BPS and depression had GRA 2or 3 (47.5% vs 59.2%) compared with those without depression (p = 0.043). Conclusion Patients with IC/BPS have more medical comorbidities, but these were not associated with cystoscopic bladder conditions. In patients with functional somatic and psychiatric disorders, RANTES and 8-OHdG were significantly lower than in those without comorbidities. Clinical trial registration Not available