The placebo effect in overactive bladder syndrome.

Overactive bladder syndrome (OAB) is a condition that involves urinary urgency and affected individuals are usually treated with behavioral therapy and antimuscarinic agents as first-line therapies. Existing evidence from clinical trial data suggests that a positive placebo effect occurs in patients receiving treatment for OAB. In our systematic Review of placebo-controlled, randomized trials in OAB, we show statistically significant improvements in three patient-reported outcomes-incontinence episodes per day, micturition episodes per day and mean micturition volume from baseline-after placebo in randomized studies for OAB. The findings could highlight the brain's role in the pathophysiology of OAB or the role of additional bladder training conducted as part of OAB clinical trials. More research is needed to determine the underlying mechanisms of the placebo effect in OAB.