Application of peritoneal dialysis in elderly patients by classifying the age into young-old, old, and oldest-old

Background: A greater number of end-stage renal disease patients are receiving peritoneal dialysis (PD) or hemodialysis (HD) in Japan. However, medical concerns with advancing age have been raised in PD utilization for elderly patients. The objective of this study was to address the indications for PD in elderly patients in terms of medical concerns such as nutrition state, residual renal function, dialysis efficiency, peritonitis, cardiovascular disease (CVD) complications, and technique survival. Methods: In a retrospective, two-center study, we evaluated 247 patients who newly started PD from 2002 to 2008. All patients were divided into four groups: young (<64 years, n = 99), young-old (65-74 years, n = 55), old (75-84 years, n = 62) and oldest-old (>85 years, n = 31). Serum albumin, hemoglobin, β₂-microglobulin, cardio-thoracic ratio, 24-hour urine collection and spent dialysate volume was collected at the initiation of PD and after 1, 2, 3, and 4 years. PD withdrawal, occurrence of CVD complications, peritonitis and death were recorded. Results: Nephrosclerosis as a primary disease increased with advancing age (p = 0.001). At baseline, gender, body weight, serum creatinine, hemoglobin and cardio-thoracic ratio were significantly different among the four groups. No significant decrease was shown in urine output with advancing age. The spent dialysate volume was significantly lower (mean 3.8 liters/day) in the oldest-old group compared with the other groups (p = 0.001). However, a smaller volume of PD fluid in the oldest-old group was not accompanied by a significantly higher serum β₂-microgloblin level compared with the other groups and there was no reason of PD withdrawal for underdialysis in the old and oldest-old groups. Neither the incidence of CVD complications nor that of peritonitis was increased with advancing age. There was no significant difference in technique survival rate excluding death between each group. These findings suggest that there are no medical concerns to avoid PD therapy in elderly end-stage renal disease patients.