Urobiome changes differ based on OAB treatment in adult females.

INTRODUCTION AND HYPOTHESIS: Representatives of two classes of oral medication are often used to treat urgency urinary incontinence (UUI): solifenacin, an M3-receptor-selective antimuscarinic, and mirabegron, a beta-3 agonist. Two previous asynchronous drug-specific studies suggested different interactions between these medications and the urobiome despite identical methodologies, including recruitment, sample procurement, medication dose escalation strategy, determination of 12-week responders versus nonresponders, and data collection. This analysis compares data from these two studies using a uniform analytic approach.

METHODS

Urine was collected aseptically via transurethral catheter from consenting participants for subsequent processing by the Expanded Quantitative Urine Culture (EQUC) protocol in two cohorts (n=50 and n=47) that were demographically similar. Species accumulation curves were generated to compare the total number of unique species detected. Indices that measure richness, evenness, and/or abundance were used to compare alpha (within sample) diversity. The Bray-Curtis Dissimilarity Index was used to determine between sample (beta) diversity.

RESULTS

The majority of the 40 species detected in the pre-treatment urobiomes were detected in both cohorts. Both pre-treatment urobiomes were substantially similar in species richness, evenness, and diversity. Differences in pre-treatment urobiomes were associated with treatment response for solifenacin-treated participants only. In contrast, the pre-treatment urobiomes of mirabegron-treated participants were not associated with treatment response. Changes in the post-treatment urobiomes were detected in both cohorts with an increase in richness for both solifenacin (5-mg dose only) and mirabegron.

CONCLUSIONS

Pre-treatment urobiome characteristics were associated with treatment response in participants treated with solifenacin, but not mirabegron. Differences exist in urobiome response after treatment with two medications that have known differences in mechanism of action.