Peritoneal dialysis adequacy and risk of death

Background. The purpose of this study was to evaluate the relationship betw een dialysis dose, patient characteristics. and medical comorbidities on mo rtality in chronic peritoneal dialysis patients. Methods. This work comprised a study cohort of 1446 patients obtained from a random sample of chronic peritoneal dialysis patients from each dialysis center in three southeastern states. Data collected on a standardized form were used to calculate weekly Kt/V urea and creatinine clearance. Data were linked to Network files containing data on patient demographic and medical comorbidities. Results. Both weekly Kt/V urea and creatinine clearance were measured at le ast once in only 60.5% of continuous ambulatory peritoneal dialysis (CAPD) patients and 63.7% of cycler patients. Among the 873 patients who had at le ast one calculable adequacy measure, the mean (+/-SD) weekly Kt/V urea was 2.13 +/- 0.55, and the normalized mean weekly creatinine clearance was 62.9 +/- 20.4 L/week/m(2). During the seven month period of follow-up, there we re 140 deaths. In separate logistic regression models that included all of the studied risk factors, using separate variables for the urinary and peri toneal components of dialysis adequacy, each 10 L/week/1.73 m(2) increase i n the urinary component of weekly creatinine clearance was associated with a 40% decreased risk of death, and each 0.1 unit increase in the urinary co mponent of weekly Kt/V urea was associated with a 12% decreased risk of dea th. In contrast, the dialysate components of neither weekly creatinine clea rance nor weekly Kt/V urea were predictive of death. Other factors that wer e associated with an increased risk of death included increasing age, diabe tes mellitus as the cause of end-stage renal disease (ESRD), and a history of myocardial infarction. Conclusions. Residual renal function, as expressed by weekly creatinine cle arance or Kt/V urea, is an important predictor of death in chronic peritone al dialysis patients. The nonsignificant findings regarding peritoneal clea rances and mortality may possibly be secondary to the narrow range of perit oneal clearances in this study cohort.