Ageing and the bladder mucosa: A scoping review of recent animal model studies

Abstract

The incidence of lower urinary tract symptoms increases with age. People with bladder disorders who are older than 60 years are more likely to comply and persist with treatment regimens, such as antimuscarinic medications for overactive bladder. Suggestions for these differences include lifestyle factors, greater compliance with medication prescription, or pharmacological and physiological changes to the receptors within the bladder tissue itself. This scoping review focused on the latter and sought to identify if there is recent evidence to support a prominent role for the internal lining of the urinary bladder, the bladder mucosa (urothelium with lamina propria), in age-related alterations. Although there continues to be substantial urological research in humans, animal models remain highly important for the assessment of physiological and pharmacological changes in the bladder. Recent work in this field brings insights into the overall understanding of bladder function and dysfunction. The PUBMED database was searched for studies published between 2018 and 2022. From the 25 articles identified, 10 were eligible for inclusion in the evaluation, and a risk of bias assessment was performed. Studies reported a variety of age-related alterations in the bladder mucosa. The most pronounced changes appear to be an inhibition of the mucosal barrier function and signalling pathways with ageing. Ageing also appeared to inhibit receptor systems associated with contraction inhibition, potentially leading to enhanced contractions. The overall evidence suggests that the increased prevalence of bladder contractile disorders seen in ageing may be due, in some part, to physiological alterations occurring within the bladder tissue itself.