Recovery of renal function after radical nephrectomy and risk factors for postoperative severe renal impairment: A Japanese multicenter longitudinal study

Abstract
Objectives To investigate longitudinal changes in renal function after radical nephrectomy, and to explore risk factors of postoperative severe renal impairment in a Japanese multicenter cohort. Methods The present retrospective study included 701 patients who had no metastasis, end‐stage kidney disease or bilateral kidney cancer, who underwent radical nephrectomy and who were followed up for at least 1 year. The longitudinal change in postoperative renal function during a 10‐year follow‐up period was evaluated according to the presence or absence of potential risk factors including greater age, chronic kidney disease, hypertension, diabetes mellitus and cardiovascular disease. A slope of annual change in estimated glomerular filtration rate was analyzed using a linear mixed model. Associations between the potential risk factors and a >50% estimated glomerular filtration rate decrease were evaluated using a multivariate Cox regression model. Results Overall, the postoperative estimated glomerular filtration rate recovered over time with a significant positive slope of 0.34 mL/min/1.73 m2/year. Renal function did not tend to recover in patients with chronic kidney disease, hypertension, diabetes mellitus or cardiovascular disease. The multivariate analysis showed that greater age and diabetes mellitus were independent risk factors for severe renal impairment. Conclusions Overall, patients who had deteriorated renal function immediately after radical nephrectomy recovered over time. However, patients with chronic kidney disease, hypertension, diabetes mellitus and cardiovascular disease did not tend to recover renal function postoperatively. Greater age and diabetes mellitus were independent risk factors for a >50% decrease in estimated glomerular filtration rate.