Is the beneficial effect of antimuscarinics related to motor or sensory changes in the bladder?

Introduction And Hypothesis: The aim of the study was to assess the sensory and motor effects of antimuscarinic treatment on the bladder in women with overactive bladder, detrusor overactivity demonstrated on urodynamics and a mean bladder wall thickness (BWT) greater than 5 mm.

Methods: Fifty-eight women underwent treatment with antimuscarinics in 12 weeks. Before treatment and at 1, 2, 6 and 12 weeks of treatment, women completed the patient perception of bladder condition (PPBC) single-item global questionnaire, indicated the severity of their urgency on a visual analogue scale (VAS) and underwent transvaginal ultrasound to determine mean bladder wall thickness (BWT).

Results: PPBC and VAS scores for urgency declined throughout the treatment course whereas mean BWT declined during the first 6 weeks of treatment and then reached a plateau after falling to below 5 mm.

Conclusion: The mechanism of action of antimuscarinics appears to be a complex interaction of sensory and motor components.