Prognostic value of red cell distribution width in elderly patients undergoing peritoneal dialysis

Abstract

Objective To examine the clinical characteristics and red cell distribution width(RDW)changes and to investigate the prognostic value of RDW in elderly patients undergoing peritoneal dialysis(PD). Methods We retrospectively analyzed the data of 59 elderly patients aged 60 or over who had undergone regular PD for over three months at Beijing Hospital from July 1, 2005 to June 30, 2017.All patients were followed up until the occurrence of a composite event or until December 31, 2017.General characteristics, baseline laboratory data, RDW at baseline, and time-average RDW during the follow-up were compared between the non-survival group and the survival group.Cox regression analysis was performed to determine whether RDW was an independent risk factor of all-cause mortality. Results Fifty-nine elderly PD patients with a mean age of(70.5±6.6)years were included.The median follow-up duration was 40(25, 56)months and the median survival duration was 57(36.6, 74.4)months.The 1-, 3-, and 5-year survival rates of all patients were 98.3%(n=58), 72.9%(n=43), and 52.5%(n=31), respectively.Twenty-eight patients died during the follow-up, of whom 15 died of infection, 8 of cardio-cerebrovascular disease and 5 of other causes.Non-survivors had higher Charlson Comorbidity Index(CCI)scores, higher levels of RDW at baseline, higher time-average RDW, lower initial total KT/V, and lower initial total CCr(all P<0.01). In univariate analysis, high CCI, high basic RDW, high time-average RDW, low serum albumin, low serum ferrum, and low serum cholesterol were associated with all-cause mortality(all P<0.05). In multivariate-adjusted Cox analysis, high CCI(HR=1.679, 95%CI: 1.238-2.236, P=0.001)and high time-average RDW(HR=1.889, 95%CI: 1.195-2.987, P=0.007)were independent predictors for all-cause mortality in elderly PD patients. Conclusions Time-average RDW may independently predict the mortality of elderly PD patients.The prognostic value of dynamic RDW may be similar to that of CCI. Key words: Peritoneal dialysis; Erythrocytes; Nephrosis; Cause of death