Lipid parameters including lipoprotein (a) in patients undergoing CAPD and hemodialysis

Abstract

Objective: Dyslipidemia possibly contributes to the vascular complications commonly afflicting uremic patients. Lipoprotein (a) [Lp(a)] has been identified as an independent risk factor for atherosclerotic vascular disease. The aim of our study was to compare lipidparameters, including Lp(a), between hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) patients.

Design: A cross-sectional study.

Setting: University Medical Center.

Participants: Forty CAPD and 40 HD patients carefully matched for age, sex, body mass index (BMI), smoking habits, and duration of dialysis were studied. A group of 40 healthy individuals matched for age, sex, BMI, and smoking habits was used as control.

Interventions: None.

Main outcome measures: Serum lipid parameters and atherogenic risk ratios were the main outcome measures.

Results: Both groups of dialysis patients had increased serum triglycerides and decreased levels of ApoA1 and HDL cholesterol compared to controls. Moreover, the risk ratios total cholesterol/HDL cholesterol and LDL cholesterol/HDL cholesterol were significantly higher, and the ratio ApoA1/ApoB was significantly lower in both groups of patients in comparison to the normal subjects. Both groups of dialysis patients exhibited decreased ratios of LDL cholesterol/ApoB and HDL cholesterol/ApoA1, suggesting the presence of compositional lipoprotein changes. CAPD patients had a more atherogenic lipid profile compared to HD patients, since they exhibited higher levels of total and LDL cholesterol, of ApoB as well as of the ratios total cholesterol/HDL cholesterol and LDL cholesterol/HDL cholesterol, and lower levels of the ratio ApoA1/ApoB compared to HD patients. Both groups of dialysis patients had increased serum Lp(a) levels. Even though CAPD patients had higher serum Lp(a) levels than HD patients, the differences between these two groups were only marginally statistically significant (p = 0.056 by Mann-Whitney U-test). Uremic dyslipidemia was positively correlated with serum albumin levels in both groups of patients.

Conclusion: CAPD patients exhibit a more atherogenic lipid profile than that of HD patients. The marked disturbances in Lp(a) levels may further increase the vascular risk in both groups of patients.