The anemia in continuous ambulatory peritoneal dialysis patients is related to Kt/V index

Anemia in chronic renal failure causes a number of serious problems to the patient. As a result, it is imperative to make use of all rational options to alleviate it. The present study addresses the question, the answer to which is not yet known, whether or not the degree of anemia depends on the efficacy of continuous ambulatory peritoneal dialysis (CAPD) and, if so, what the importance of peritoneal clearance and residual renal function is. A significant correlation between the hematocrit (Hct) and the total weekly Kt/V index (tKt/V) (r = 0.61, p<0.01), total weekly creatinine clearance (tCLCR) (r = 0.50, p<0.05), and residual glomerular filtration rate (r = 0.43, p<0.05) was demonstrated in a group of 22 CAPD patients. Stepwise regression analysis showed that of all the variables monitored, Hct depends exclusively on tKt/V (p<0.01, r2 = 0.37). The value of Hct in a group of patients with a tKt/V <2.3 (n = 15) was 28.9+/-1.2% (arithmetic mean +/- SEM) while in a group with a tKt/V > or =2.3 (n = 7), it was 35.1+/-1.9% (p<0.01). On dividing tKt/V and tCLCR into their peritoneal and renal components, a significant correlation between Hct and renal Kt/V (r = 0.47, p<0.05) was found; stepwise regression analysis identified renal Kt/V (p<0.01) and peritoneal Kt/V (p<0.05), with R2 = 0.38 as major variables with an effect on Hct. The authors conclude the efficacy of blood purification is another factor affecting renal anemia in CAPD patients. The relationship between anemia and blood purification is best expressed using the Kt/V index. The Kt/V provided by one's own kidneys seems to be of greater importance for anemia than the Kt/V provided by peritoneal dialysis. The results provide the basis for prospective interventional studies.