Bladder Capacity is a Biomarker for a Bladder Centric versus Systemic Manifestation in Interstitial Cystitis/Bladder Pain Syndrome

Abstract

Interstitial cystitis/bladder pain syndrome presents a significant clinical challenge due to symptom heterogeneity and the myriad associated comorbid medical conditions. We recently reported that diminished bladder capacity may represent a specific interstitial cystitis/bladder pain syndrome subphenotype. The objective of this study was to investigate the relationship between anesthetic bladder capacity, and urological and nonurological clinical findings in a cohort of patients with interstitial cystitis/bladder pain syndrome who had undergone therapeutic urinary bladder hydrodistention. This is a retrospective chart review of prospectively collected data on women diagnosed with interstitial cystitis/bladder pain syndrome between 2011 and 2015 who underwent bladder hydrodistention. Assessments in each patient included a detailed history and physical examination, ICPI (Interstitial Cystitis Problem Index), ICSI (Interstitial Cystitis Symptom Index) and PUF (Pelvic Pain and Urgency/Frequency Patient Symptom Scale). Bladder capacity was determined during bladder hydrodistention with the patient under general anesthesia. Mean age was 45.8 years and mean bladder capacity was 857 ml in the 110 enrolled patients. We found a significant inverse correlation between bladder capacity and scores on 3 gold standard interstitial cystitis/bladder pain syndrome metrics, including ICPI (p = 0.0014), ICSI (p = 0.0022) and PUF (p = 0.0009) as well as urination frequency (p = 0.0025). Women with higher bladder capacity were significantly more likely to report depression (p = 0.0059) and irritable bowel syndrome (p = 0.022). Low bladder capacity while under anesthesia was significantly associated with high symptom scores on 3 validated interstitial cystitis/bladder pain syndrome questionnaires as well as with urinary frequency. However, it was not associated with depression or other common systemic pain problems. These results suggest that low bladder capacity is a marker for a bladder centric manifestation of interstitial cystitis/bladder pain syndrome.