Association between Renal Injury and Prognosis of Elderly Overactive Bladder Patients: A Study Based on NHANES Database

Background The prevalence of overactive bladder(OAB) rises with age and substantially impacts patients’ quality of life, sleep quality and mental health. However, many older adults perceive OAB as non-fatal, treatment-seeking behavior among seniors is low, particularly in economically disadvantaged regions. The aim of this study was to explore the influence of OAB on the survival time of the elderly and the relationship between renal injury index and survival time of OAB patients. Methods A total of 6065 participants from the National health and Nutrition examination survey(Nhanes) were included in the study. Tendency score matching is used to control data bias. Predictors of survival were identified through a three-stage process: initial univariate Cox regression, feature selection via Lasso regression, and confirmation with multivariate Cox regression. Mediating analysis was used to confirm whether OAB can independently affect survival time. Six machine learning algorithms, logistic Regression, Gradient Boosting, AdaBoost, Support Vector Machine, K-Nearest Neighbors, Gaussian Naive Bayes, and generalized additive model(GAM) were used to evaluate the correlation between renal injury index and prognosis of OAB patients. Results Under the control of other variables, the survival time of OAB patients was still shorter than normal people. OAB was an independent risk factor affecting the survival time of the elderly population, and the influence of OAB on the survival time did not depend on other covariates. Machine learning results showed that urinary albumin, serum creatinine, glomerular filtration rate(eGFR), urinary albumin-to-creatinine ratio(UACR) could predicted the survival time of OAB patients. The GAM results showed that UACR was negatively correlated with the survival time of OAB patients. Conclusion OAB could effect the long-term survival time of the elderly by damaging renal function, and UACR may be the potential index to predict the survival time of OAB patients.