Clinical risk factors associated with rapid renal function decline after nephrectomy

Abstract

Background: Nephrectomy inevitably reduces renal mass and increases the risk of chronic kidney disease (CKD). Identifying predictors of early renal decline after surgery is crucial for optimizing long-term outcomes. Methods: We retrospectively analyzed 1723 patients with renal cell carcinoma (RCC) or upper tract urothelial carcinoma (UTUC) from the Taiwan Cancer Database linked with the Chang Gung Research Database (2005–2024). Rapid decline was defined as a decrease in estimated glomerular filtration rate (eGFR) > 3 mL/min/1.73 m² between postoperative month 3 and month 15. Postoperative acute kidney injury (AKI) was defined according to KDIGO criteria. Logistic regression was used to evaluate demographic and clinical predictors. Risk stratification was performed according to diabetes mellitus (DM) and AKI. Results: Of 1723 patients, 720 (41.8%) experienced rapid decline. Compared with those without decline, affected patients were older, more often female, and had higher rates of hypertension, DM, and hyperlipidemia. Preoperative eGFR < 45 and postoperative AKI were also more common. In multivariate analysis, DM (OR 1.56, 95% CI 1.25–1.94, p < 0.001) and postoperative AKI (OR 1.85, 95% CI 1.43–2.38, p < 0.001) remained independent predictors. Risk stratification showed a stepwise increase in decline: 33.9% without either factor, 47.8% with DM only, 53.3% with AKI only, and 57.8% with both. Patients with both conditions had nearly a 1.7-fold higher risk compared with those without either factor, and Kaplan–Meier analysis confirmed significantly worse outcomes over time (log-rank p < 0.05). Conclusions: DM and postoperative AKI independently predict early renal deterioration after nephrectomy. Patients with both factors represent a high-risk subgroup requiring intensified surveillance and preventive strategies.