Effect of Polyuria on Bladder Function in Diabetics versus Non-Diabetics: An Article Review

Objectives: To review studies that investigated the role of polyuria on bladder function. Methods: We performed a search of the English literature through PubMed. We only included animal studies that assessed parameters of bladder function and had compared diabetic and non-diabetic polyuric animals. Results: Fluid intake and urine output were increased in diabetic and polyuric animals; failure to appropriately gain weight was seen in diabetics only. All but 1 study reported increase in bladder weight in both groups. In cystometrograms, control mice showed reductions in basal bladder pressure over time, whereas diabetic and diuretic groups stabilized or increased. Both groups showed larger bladder capacity. Overall, many characteristic changes in cystometrographic studies in diabetic animals could be attributed to polyuria. In histological studies, bladder hypertrophy, increase in smooth muscle and urothelium, and increase in protein and DNA content per bladder were observed in diuretic and diabetic rats. Actual collagen cross-sectional area did not change during the progression of diabetes or diuresis but decreased over time in both groups as a percentage of total tissue area. Both groups expressed less type I collagen mRNA and TGF-beta-1 mRNA. Conclusions: Although lower urinary tract changes in anatomy and function in diabetic patients might arise from a number of causes, polyuria seems to play an important causative role.