Comorbid Bladder Pain Syndrome and Vulvodynia - a Cross-sectional Analysis of the UNICORN-4 Study

Overview

Journal BMC Womens Health

Publisher Biomed Central

Specialty Gynecology & Obstetrics

Date 2025 Feb 19

PMID 39972456

Authors

Nobuo Okui

Affiliations

Soon will be listed here.

Abstract

Background: Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC) and vulvodynia often coexist, exacerbating patient symptoms and complicating the diagnosis and treatment. This study aimed to identify distinct subtypes within a BPS/IC and vulvodynia cohort and evaluate their symptom profiles, psychological characteristics, and sexual function indicators.

Methods: A cross-sectional analysis was conducted on 150 female patients diagnosed with BPS/IC and vulvodynia. The patients completed validated questionnaires assessing bladder symptoms, psychological distress (PHQ-9 and GAD-7), and sexual function (FSFI and FSDS-R). Hierarchical and K-means clustering were used to identify patient subgroups.

Results: Three distinct clusters were identified. Cluster 1 exhibited moderate bladder-specific symptoms and psychological distress. Cluster 2 had severe bladder symptoms and the highest psychological distress. Cluster 3, defined as the vulvodynia-predominant subtype, featured severe vulvodynia, significant psychological distress, and minimal bladder symptoms, aligning with a non-urologic pelvic pain phenotype. Sexual function was significantly impaired across all clusters, with Cluster 3 showing the most severe dysfunction.

Conclusions: This study highlights the heterogeneity within BPS/IC and vulvodynia populations. The identification of a vulvodynia-predominant subtype and non-urologic pelvic pain phenotype emphasizes the need for personalized treatment strategies addressing both physical and psychological factors, particularly sexual dysfunction and psychological distress.

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