title: Estimated versus predicted creatinine generation as an indicator of compliance with the prescribed dose of continuous peritoneal dialysis.
abstract: The expression (Estimated-Predicted)/Predicted creatinine generation ¿(E-P)/P¿ has been proposed as an index of compliance in continuous peritoneal dialysis (CPD). We attempted to define an (E-P)/P value that can be used as a cut-off for non-compliance and to characterize the relation of (E-P)/P to serum albumin. In 324 clearance studies, (E-P)/P had a normal distribution with a mean of +0.094 and an SD of 0.357. In these studies, there was a weak correlation between (E-P)/P and serum albumin (r = 0.12, P < 0.05), but (E-P)/P was not a predictor of serum albumin by logistic regression. In 34 CPD patients, who had an increase in the dose of CPD resulting in an increase in measured creatinine clearance from 43.8 +/- 14.0 to 66.1 +/- 17.6 L/1.73 m2 weekly (P < 0.001), (E-P)/P increased correspondingly from +0.018 +/- 0.284 to +0.153 +/- 0.369 (P = 0.018), although all subjects should be in a steady state of creatinine excretion in the second study. The rise in (E-P)/P was statistically significant in the subgroup of 17 subjects who had a decrease in serum albumin, but not in the subgroup of 14 subjects who had an increase in serum albumin from the first to the second clearance study. The (E-P)/P cut-off for a definitive diagnosis of CPD non-compliance may be around +0.400 or +0.500. The findings of this study suggest that non-compliance, as indicated by (E-P)/P, has an adverse effect on serum albumin and that non-compliance increases after a prescribed increase in the dose of CPD.
authors.affiliation: Renal Section, Albuquerque Veterans Affairs Medical Center, New Mexico, USA.
authors.forename: A H
authors.initials: AH
authors.lastname: Tzamaloukas
authors.forename: M
authors.initials: M
authors.lastname: Braun
authors.forename: D
authors.initials: D
authors.lastname: Malhotra
authors.forename: G H
authors.initials: GH
authors.lastname: Murata
mesh_terms: D003404:Creatinine / Q000652:urine*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy; D016014:Linear Models; D008297:Male; D010349:Patient Compliance; D010531:Peritoneal Dialysis, Continuous Ambulatory; D012709:Serum Albumin / Q000378:metabolism
chemical_list: D012709:Serum Albumin; D003404:Creatinine