Over-active bladder

An improved 10-site injection protocol of onabotulinumtoxinA reduces clean intermittent catheterisation use; BMI and UDI are independent predictors of sling surgery outcomes; urgency and nocturia are not being adequately addressed by muscarinic antagonists and possibly the greater family of ß-3 agonists.

Dr Kurt McCammon (Eastern Virginia Medical School, USA) compared data from 10-sites of injection of onabotulinumtoxinA vs the standard 20-site approach (both arms administered the same total amount of botox) in females with over-active bladder (OAB). He concluded that 10 injection sites (avoiding the bladder dome) preserved retention, improved quality of life, and was associated with lower clean intermittent catheterisation use. This study tested the outcomes of patients treated with the same number of onabotulinumtoxinA units, but in only 10 injection sites, 2 being placed in the trigone, and none in the bladder dome. The investigators observed that the efficacy of urinary incontinence episodes in the onabotulinumtoxinA 10-site group was better than the placebo group (to be expected), but also that the patients that were completely dry at week 2, 6, and 12 were significantly higher in the onabotulinumtoxinA 10-site group. In total, 5% in this alternative group had no retention, which is similar to the rates reported to 20-site onabotulinumtoxinA injection. The authors concluded that the improvements in urinary incontinence as well as quality of life standards was similar with the alternative injection paradigm to those achieved with the standard 20-site regimen. However, the alternative 10-site injection paradigm cohort required no (0%) clean intermittent catheterisation use vs 5.2 % with standard paradigm. Adverse event safety was consistent with previous studies associated with low clean intermittent catheterisation use. These data strongly suggest that we do not have to use 20 injection sites, but that the same effect with can be achieved with 10 sites and that we should stay away from the dome to preserve contractility.

Dr Philip Toosz-Hobson (Birmingham Women’s Hospital, United Kingdom), a uro-gynaecologist, interrogated whether patient characteristics influence the outcomes of sling surgery for stress incontinence. Delving into the 19,000 cases in the British Society of Urogynaecology database, they investigated body mass index (BMI, nearly all patients could be analysed) and urodynamic investigation (UDI) prior to surgery (n=9,737). Patients with a low BMI receiving slings had the fewest OAB symptoms post-surgery; those with high BMIs had linearly more symptoms, and the data clearly indicated that BMI stratification alone can predict outcome. To their surprise, when they stratified the smaller subset of patients with UDI results, UDI was also a strong predictor of the outcome of sling surgery; patients with a straightforward urodynamic-based diagnosis of stress incontinence had clearly better outcomes than those patients for whom unusual activity observed by UDI.

Prof. Martin Michel (University of Mainz, Germany) held a presentation about unmet needs in OAB patients. In particular, he focused on how many patients actually become symptom-free after treatment with propiverine. Using real-world evidence, he concluded that whereas marked improvement was reported in incontinence and frequency symptoms as a result of propiverine treatment, neither urgency nor nocturia were generally improved. This conclusion may be applicable to all muscarinic antagonists as well as possibly the greater family of ß-3 agonists. These data underscore a gap in medical treatment; the greatest medical needs in OAB efficacy are urgency and nocturia, since both have major adverse impact on quality of life, yet these are precisely the two symptoms that are not being improved by medical treatment. There are two possible explanations for this conundrum: (1) that the pathophysiology at the time of diagnosis and start of treatment is at a stage where nocturia/urgency is fully reversible, and (2) that an unidentified “master switch” can improve all outcomes for individual patients. For the latter, there is an urgent need to identify subsets of OAB patients with specific pathophysiology associated with easily assayed biomarkers. The major conclusion drawn by Prof. Michel was that significant efficacy gains may not come from new drug classes if the overall OAB population is targeted, because the important quality of life parameters are not being adequately addressed. Stratification of patients by symptoms and pathophysiology will determine future success of symptom relief in OAB.

For an EAU animated video about how to treat OAB that can be shared with your patients, please watch the following video:





Posted on 21 May 201927 June 2024