Despina Kyriaki¹, Panagiotis N. Kanellopoulos¹, Vaia D. Raikou^1,

Background/aim: High-density lipoprotein (HDL) protects against atherosclerotic plaque formation. The present study examined the relationship between HDL serum concentrations and markers of inflammation in patients on renal replacement therapies. Methods: We studied 96 dialyzed patients, 62 males and 34 females, on mean age 62.1 ± 14.27 years old and 24 healthy controls. The treatment modalities which were applied were: regular hemodialysis (HD, n = 34), predilution hemodiafiltration (HDF, n = 42) and peritoneal dialysis (PD, n = 20). Dialysis adequacy was defined by Kt/V for urea and serum bicarbonate levels were measured in gas machine. Cholesterol, triglycerides, HDL and LDL concentrations were biochemically measured. Oxidized LDL (ox-LDL) and hsCRP serum concentrations were measured by ELISA. Beta2-microglobulin (beta2M) and leptin serum concentrations were measured by radioimmunoassays. Results: The patients presented increased beta2M, hsCRP, leptin and triglycerides than control group, but HDL exhibited significant reduction (p < 0.05). The patients on PD had significantly higher serum bicarbonate levels and lower oxLDL than other groups of patient (p < 0.05). HDL positively associated with Kt/V, presented negative correlation with both, ox-LDL and beta2M (r = -0.237, p = 0.02 and r = -0.291, p = 0.004 respectively). Beta2M was positively associated with hsCRP (r = 0.257, p = 0.01). Serum bicarbonate levels were inversely associated with hsCRP and oxLDL (r = -0.232, p = 0.05 and r = -0.289, p = 0.01 respectively). Conclusions: The low HDL was associated with increased beta2M concentrations in patients on renal replacement therapies. The HDL reduction was combined with an elevation of oxLDL, which was lower in PD patients compared to hemodialysis modalities patients. The acidosis state influenced both, the inflammatory environment and the increase of oxidized lipids. Dialysis adequacy was positively correlated to HDL serum concentrations.

hemodialysis, HDL lipoprotein, beta2-microglobulin, inflammation, hsCRP, acidosis