Daytime urinary incontinence in children and young adults is a common problem with which can negatively impact on an individual’s quality of life. Adverse effects can include feelings of social isolation, depression and disturbed sleep.
Causes and standard treatment
The most frequent cause of daytime urinary incontinence, which predominately but not exclusively affects girls, is overactivity of the bladder detrusor muscle (OAB). Standard treatment consists of identifying and eliminating risk factors (poor fluid intake, poor toileting habits, constipation, stimulant intake e.g. caffeine), followed by anticholinergic medication if simple measures fail. In addition, Posterior Tibial Nerve Stimulation (Neuromodulation) is a useful alternative option. While this is often successful, some children are unresponsive to all options or have significant side effects from medication.
In adult practice a standard approach would be to use an intravesical injection of Botulinum toxin (Botox A). While this is a very effective treatment, there is a risk of temporary urinary retention that requires a period of intermittent catheterisation until it resolves. Botox A is licensed for treating OAB in adults but not currently in children.
The OAB study is looking at young adults aged 12-17 with OAB who have tried conventional treatment without success. After appropriate consent and screening the study randomises patients to receive either 25, 50 or 100 IU of Botox A injected directly into the bladder wall. The primary end point is number of wetting episodes with a secondary end point of voiding episodes. Quantifying the risk of urinary retention is also an important end point.
The OAB study is a multinational randomised trial with the patient and surgeon blinded to the dose of Botox A administered. The research is being co-ordinated in Aberdeen by the ScotCRN and is funded by Allergan, the manufacturer of Botox A, as part of their licencing agreement, and is a multinational randomised trial with the patient and surgeon blinded to the dose of Botox A administered.