Chronic kidney disease before and after partial nephrectomy.

PURPOSE

We performed a multi-institutional retrospective cohort study to evaluate baseline renal function of patients who underwent partial nephrectomy for renal tumors, and determined rates of progression to higher stages of chronic kidney disease.

MATERIALS AND METHODS

The Modification of Diet in Renal Disease study equation was used to estimate glomerular filtration rate. Preoperative and postoperative serum creatinine values were obtained from patients who underwent partial nephrectomy at 6 institutions with a normal contralateral kidney, and had baseline chronic kidney disease stage I (estimated glomerular filtration rate greater than 90 ml/minute/1.73 m(2)), II (estimated glomerular filtration rate 60 to 89 ml/minute/1.73 m(2)) or III (estimated glomerular filtration rate 30 to 59 ml/minute/1.73 m(2)). The end point was change in chronic kidney disease stage at long-term followup (3 to 18 months). Multivariate logistic and Cox regression models tested the association of newly acquired chronic kidney disease stage III or greater with pertinent demographic, tumor and surgical factors.

RESULTS

For 1,228 patients with followup creatinine data at least 3 months after partial nephrectomy median baseline glomerular filtration rate was 74 ml/minute/1.73 m(2). At baseline 19%, 59% and 22% of patients had chronic kidney disease stage I, II and III, respectively. At long-term followup for patients with baseline chronic kidney disease stage I or II median postoperative glomerular filtration rate was 67 ml/minute/1.73 m(2) with 29% having progression to chronic kidney disease stage III or greater. Increasing age, female gender, increasing tumor size, clamping of the renal artery and vein, and lower preoperative estimated glomerular filtration rate were independently associated with newly acquired chronic kidney disease stage III or greater. The presence of comorbid conditions such as coronary artery disease, diabetes mellitus or hypertension did not independently predict an increased risk of higher chronic kidney disease stage.

CONCLUSIONS

Chronic kidney disease stage III or greater will develop postoperatively in approximately a third of patients with an estimated glomerular filtration rate greater than 60 ml/minute/1.73 m(2), and this progression is associated with definable demographic, tumor and surgical factors.