The effect of residual renal function at the initiation of dialysis on patient survival

The optimal time point for initiating renal replacement therapy in patients with end-stage renal disease remains controversial. The primary objective of our study was to determine the effects of residual renal function at the beginning of renal replacement therapy on the mortality of patients with end-stage renal disease.

We retrospectively studied the clinical outcomes in patients (n=210) with end-stage renal disease who underwent renal replacement therapy at our hospital between 2000 and 2005; all patients were followed for more than 1 year. We used the Modification of Diet in Renal Disease equation to estimate residual renal function.

Of the 210 patients who received renal replacement therapy, 108 were treated with hemodialysis and 102 were treated with peritoneal dialysis. Thirty-three patients died, and the mean survival period was 37.3+/-17.7 months. The survival rates were compared based on the estimated glomerular filtration rate; no difference in survival rates was observed (p=0.27). Subgroup analysis in the hemodialysis group showed that patients who began chronic dialysis at a lower estimated glomerular filtration rate had higher mortality rates (p<0.05); patients treated with peritoneal dialysis showed no significant difference in mortality rate (p=0.50).

Although there was no difference in the mortality rate based on residual renal function, hemodialysis patients with a lower estimated glomerular filtration rate showed a higher mortality rate than those with a higher estimated glomerular filtration rate.