Survival of elderly patients on peritoneal dialysis: retrospective study of 292 patients, from 1982 to 1999.

BACKGROUND: Dialysis is becoming increasingly frequent in patients over 75 years of age. Age is a superimposed comorbid factor commonly associated with poor prognosis in these patients. OBJECTIVE: To analyze the survival of 292 patients aged over 75 years on initiation of peritoneal dialysis (PD) from September 1982 to September 1999. DESIGN: Retrospective study. SETTING: Nephrology department in a University Hospital. RESULTS: Mean age was 81.5 years (range 75-92 years); 178 patients were over 80 years and 60 patients were over 85 years. Sex ratio was 136F/156M. Ninety-day mortality rate was 12%. Excluding the first 3 months, median patient survival was 21.6 months; 226 patients died on PD and 24 were shifted to hemodialysis. Survival was inversely correlated with the Charlson combined comorbidity index (CCI), but independent of predialysis hemoglobin and serum albumin levels. Over three selected periods, 1982-1989, 1989-1995, and 1995-1999, an increase was found in mean age (79.7 +/- 3.3, 82.6 +/- 3.9, and 81.8 +/- 4.4 years; p < 0.001), CCI (7.6 +/- 1.59, 8.0 +/- 1.52, and 8.5 +/- 1.63; p = 0.01), and predialysis creatinine clearance (6.2 +/- 2.3, 6.4 +/- 2.4, and 9.8 +/- 3.8 mL/minute; p < 0.001). Median survival was similar in the various selected periods (21.0, 21.5, and 25.4 months). The incidence of peritonitis decreased from 0.63 to 0.21 episodes per patient year. CONCLUSION: From 1982 to 1999, mean age and comorbidity increased on initiation of dialysis in elderly patients, with no increase in mortality. Survival in elderly patients on PD was related to the age-comorbidity index.