Increased Plasma Lipoprotein(a) in Continuous Ambulatory Peritoneal Dialysis Is Related to Peritoneal Transport of Proteins and Glucose

Abstract

Markedly increased plasma lipoprotein(a) [Lp(a)] levels have recently been reported in continuous ambulatory peritoneal dialysis (CAPD) patients but the genesis is obscure. Lp(a) levels in CAPD are in general higher than in hemodialysis (HD) patients, suggesting that the dialysis procedure might be of importance. In the present study, we investigated relationships between Lp(a) and parameters related to the dialysis procedure per se (dialysis dose, peritoneal glucose absorption, protein losses and protein clearances) in 32 adult CAPD patients. Uremic patients treated with HD (n = 73) as well as a group of 43 healthy subjects served as control groups. The plasma level of Lp(a) was significantly higher in the CAPD patients (median 28.2 mg/dl) than in the HD patients (median 9.2 mg/dl) and the healthy controls (median 7.0 mg/dl), whereas Lp(a) levels in the HD patients did not differ from the healthy controls. In the CAPD patients, significant correlations were found between Lp(a) and 24-hour peritoneal and total clearance for albumin (r = 0.472 and r = 0.368, p < 0.01 and p < 0.05, respectively), and between Lp(a) and 24-hour peritoneal clearance for ββ₂-microglobulin (r = 0.421; p < 0.05). Similar correlations were found between Lp(a) and 24-hour peritoneal albumin excretion, total albumin excretion and peritoneal β₂-microglobulin excretion. Furthermore, a significant correlation was found between Lp(a) and peritoneal glucose absorption (r = 0.352; p < 0.05). Serum cholesterol showed significant correlations with 24-hour peritoneal albumin loss and 24-hour peritoneal β₂-microglobulin clearance, whereas LDL cholesterol showed a significant correlation with 24-hour peritoneal β₂-microglobulin clearance. In a longitudinal study of 12 CAPD patients, Lp(a) levels increased significantly between the start of CAPD and at follow-up 3-5 months later. The correlation of the markedly increased levels of Lp(a) with peritoneal albumin and β₂-microglobulin clearance suggests that the mechanism behind the increased Lp(a) levels may be related to the large protein losses in CAPD, perhaps via an increased synthesis rate of apolipoprotein (a) in the liver or via decreased Lp(a) catabolism in CAPD patients. Finally, the correlation between Lp(a) and peritoneal glucose absorption also indicates that the increased plasma Lp(a) levels in CAPD are related to the dialysis procedure, in particular peritoneal transport of proteins and glucose.

The relationship between atherogenic index of plasma and epicardial adipose tissue in hemodialysis and peritoneal dialysis patients

“…28,29 This heightened risk might be attributed to many factors including lose of proteins via peritoneal membrane, increased absorption of glucose from dialysate and increased serum levels of insulin in this population. 30 In accordance to these study results, usage of icodextrincontaining dialysis solutions was found to be superior to glucose-containing dialysis solutions in terms of lowering serum triglycerides and small dense LDL concentrations. 31 EAT, like abdominal visceral adipose tissue, is a metabolically active tissue that can secrete proinflammatory cytokines and utilize free fatty acids (FFAs).…”

Effects of Ginger on Serum Lipids and Lipoproteins in Peritoneal Dialysis Patients: A Randomized Controlled Trial

“…High serum levels of Lp (a) in PD patients may be due to increased hepatic synthesis of Lp (a) following loss of amino acids and proteins through PD (5,22,37,43,44). In our study, ginger consumption had no significant effect on serum Lp (a).…”

Effect of Peritoneal Dialysis Solution Type on Serum Lipid Levels in End-Stage Renal Disease

“…[28] Markedly elevated Lp(a) levels in CAPD patients have been reported. [2,29,30] A correlation between Lp(a) and peritoneal glucose absorption was reported, indicating that the increased plasma Lp(a) levels in CAPD may be related to the dialysis procedure, particularly peritoneal transport of proteins and glucose. In this study, no significant difference in Lp(a) levels between the three groups was observed.…”