Urodynamics as a Prognosticator of Mirabegron Treatment Outcomes

To determine if findings at urodynamics prognosticate improvements in overactive bladder symptoms among women receiving mirabegron treatment.

Before treatment, women completed a urodynamic investigation, a micturition diary and the Urinary Distress Inventory (UDI) with the irritative subscale UDIOAB. After 6 months mirabegron treatment, patients were clinically evaluated and completed the UDI. Associations were tested using regression analyses and nonparametric statistics.

Testing urodynamic variables for association with treatment effects in multiple linear regression analysis showed that lower volumes at first sensation to void significantly correlated with greater improvement in the UDIOAB after 6 months mirabegron treatment (B = 0.026, 95% CI 0.002-0.049, p = 0.034). Improvements in UDIOAB showed no correlation with presence of nocturia (p = 0.65), previous use of anticholinergics (p = 1), menopausal status (p = 1), any detrusor overactivity during filling (p = 1), phasic detrusor contractions during filling (p = 1), or detrusor overactivity during inhibition (p = 1).

We found limited support for clinically relevant associations between findings at urodynamics and subsequent treatment outcomes for mirabegron in routine clinical practice. Our findings do not support the role of these investigations as predictors of outcomes in patients with overactive bladder symptoms.