Serum albumin in continuous peritoneal dialysis: absence of universal predictors.

: Factors shown to affect serum albumin concentration in continuous peritoneal dialysis (CPD) were compared between two CPD populations residing in Greece (patient n = 108) and the United States (patient n = 194). Compared to the U.S. group, the Greek CPD population had higher serum albumin levels (35.1 +/- 4.6 vs 33.9 +/- 5.0 g/L, p = 0.031), was older (61.2 +/- 12.0 vs 52.7 +/- 16.5 years, p < 0.001), and had a greater number of high or high-average peritoneal solute transport types (69.4% vs 52.1%, p = 0.003). The American CPD population had a higher number of diabetics (53.1% vs 27.8%, p < 0.001), higher total Kt/Vurea (2.06 +/- 0.57 vs 1.93 +/- 0.46 weekly, p = 0.046), and higher total creatinine clearance (76.3 +/- 38.7 vs 63.4 +/- 23.5 L/1.73 m2 weekly, p < 0.001), while normalized protein nitrogen appearance values were comparable (0.95 +/- 0.21 in the Greeks vs 0.94 +/- 0.22 g/(kg x 24 hr) in the Americans, NS). A logistic regression model developed in the United States identified advanced age, diabetes, and high/high-average peritoneal solute transport as the predictors of hypoalbuminemia (serum albumin < 35 g/L). This model generated the following areas with 95% confidence intervals (CI) under the receiver operating characteristic (ROC) curve: in the Greek CPD population, ROC area 0.594 (95% CI 0.486-0.702); in the American CPD population, ROC area 0.850 (95% CI 0.810-0.890). In Greek CPD patients serum albumin appears to be affected by factors other than those identified in North America. This complicates comparisons of serum albumin, and probably morbidity and mortality, between CPD populations residing in different parts of the world.