Comparison of Voiding Dysfunction Phenotypes in Women with Interstitial Cystitis/Bladder Pain and Myofascial Pelvic Pain: Results from the ICEPAC Trial

Abstract

Objective: To evaluate whether voiding parameters differ in patients with the common overlapping pelvic pain disorders, interstitial cystitis/bladder pain syndrome (IC/BPS), and myofascial pelvic pain (MPP).

Methods: Uroflow and voiding diary assessed voiding phenotypes in this prospective cohort study (ICEPAC) of women comparing IC/BPS, IC/BPS +MPP, MPP, and healthy control (HC) subjects.

Results: In 36 HC, 24 IC/BPS, 37 IC/BPS + MPP, and 14 MPP subjects, the voiding diary measurements indicate lower voided volumes in IC/BPS and IC/BPS + MPP groups (185 ± 24 mL, 169 ± 20 mL, respectively) compared to HC and MPP groups (294 ± 24 mL, 226 ± 36 mL, respectively; P <.05, P <.05), as well as higher 24-hour voiding frequency (11.6 ± 0.8 and 11 ± 1.2 voids/24 hours, respectively; HC 7.1 ± 0.5 voids/24 hours; P <.05, P <.05; MPP group 9 ± 1.2 voids/24 hours; P <.05, P <.05). Uroflow showed higher HC average flow rate (12.87 ± 0.92) compared to IC/BPS, IC/BPS+MPP, and MPP (8.31 ± 1.20, 8.02 ± 0.80, 8.17 ± 1.38, respectively; P <.01, P <.01, P <.05) and peak flow rate (27.0 ± 1.83) and IC/BPS, IC/BPS+MPP and MPP (16.20 ± 2.2, 17.33 ± 1.64, 17.21 ± 2.69 respectively; P <.01, P <.01, P <.05).

Conclusion: This quantitative evaluation of voiding diary and uroflow metrics reveals distinct voiding phenotypes, which can aid in the diagnosis of chronic pelvic pain syndromes. Patients with IC/BPS had more pain with a full bladder despite similar overall pain scores. Peak and average flow rates do not provide any differentiating power between IC/BPS and MPP patients. A longer time to peak flow may favor MPP though this finding needs confirmation.