Fluids affecting bladder urgency and lower urinary symptoms (FABULUS): methods and protocol for a randomized controlled trial

Introduction and hypothesis: We present the design of a randomized controlled trial, Fluids Affecting Bladder Urgency and Lower Urinary Symptoms (FABULUS), with the purpose of testing the common clinical advice of treating overactive bladder by eliminating potentially irritating beverages (PIBs) that are caffeinated, artificially sweetened, citric, or alcoholic. The primary hypothesis is that women taught to reduce PIBs will show less void frequency compared with a control group instructed in diet/exercise recommendations. Secondary outcomes include change in urgency symptoms and volume per void. Methods: We report the methods for FABULUS and discuss how challenges presented in the literature and from a prior proof-of-concept feasibility trial are addressed by strengthening study design, procedures, and instruments. We introduce the concept of standardized automated tutorials for assisting participants in compliance from study start to finish. The tutorials contain a detailed explanation of the study, including tips for complying with the extensive diary requirements, and parallel tutorials to intervention and control groups for consistency in format and time of instructional content. The intervention tutorial on eliminating PIBs places emphasis on maintaining steady fluid intake volume, as fluctuations have been a confounder in prior work. Results: Study results promise to inform about both the tutorial approach and specific PIB reduction for effectively treating overactive bladder. Conclusions: OAB can have a negative impact on quality of life, and current medical treatments carry costs and side-effect risks. If simple lifestyle changes can improve or prevent these bladder symptoms, multiple medical and public health advances could result.