Urodynamic Mechanisms Underlying Overactive Bladder Symptoms in Hispanic Women

Objectives: There is limited knowledge about the role of urodynamics (UDS) for racial minority women with overactive bladder (OAB) symptoms. Prior studies suggest that OAB is more prevalent among Hispanic women compared to other ethnic groups. Hispanic women are under-represented in the OAB literature. The aim of this study is to assess the urodynamic mechanisms underlying OAB in Hispanic women.

Methods: The charts of all Hispanic women at least 18 years old who underwent UDS for lower urinary tract symptoms between 2018 and 2022 at a single academic institution were retrospectively reviewed. Only patients who had an ICD-10 diagnosis of OAB and had undergone UDS were included in the study. Race and ethnicity were self-reported by patients and documented in the electronic medical record. Means and standard deviations were reported for continuous variables and proportions for nominal variables. Univariate analysis using Fisher exact test or chi-2 test for nominal variables and Mann-Whitney test for continuous variables were performed to seek for clinical predictive factors of various urodynamic parameters.

Results: Two-hundred patients were included in the present analysis. On UDS, 38 of the 200 patients had at least one involuntary detrusor contraction (IDC) (19.0%) during filling, consistent with detrusor overactivity (DO). The mean volume of the first uninhibited contraction was 219.8mL. The first desire to void occurred on average at 143.6mL with an average cystometric capacity of 291.8mL. On pressure flow analysis, the patients had an average maximum flow of 22.0mL/s, with an average detrusor pressure at maximum flow of 36.0 cm H2O. The maximum detrusor pressure was 58.3cm H2O. The average voided volume was 275.7mL. The mean maximum urethral closure pressure was 74.6 cm H2O. A subanalysis revealed trends towards greater age (p=0.14), lower degree of pelvic organ prolapse (POP) (p=0.09), and lack of insurance (p=0.11) as predictive factors of DO on UDS.

Conclusions: Many Hispanic women with OAB do not exhibit DO on UDS. The decision to perform UDS in these patients should be prompted by other objectives than diagnosing DO. However, greater age, lower degree of POP, and lack of insurance may be predictive of DO, though they did not reach statistical significance. Thus, further prospective and randomized studies are needed to confirm our findings and elucidate the mechanisms by which social determinants of health may affect UDS performance for Hispanic women with OAB.