Association of apolipoprotein E gene polymorphism with end-stage renal disease and hyperlipidemia in patients on long-term hemodialysis

Abstract

Background: Cardiovascular diseases (CVDs) are the leading cause of death of patients with chronic renal failure. Apolipoprotein E (apoE) plays an important role in the homeostasis of cholesterol and triglycerides. Objective: We aimed to investigate the possible link(s) between apoE gene polymorphism, inflammation and lipoproteins in hemodialysis patients. Methods: We studied 109 end-stage renal disease (ESRD) patients and 97 controls. The serum lipids, apolipoproteins, lipoprotein particles, high-sensitivity C-reactive protein (hs-CRP) and total homocysteine (t-Hcy) levels and paraoxonase (PON) activity were determined in our patients. We also analyzed apoE gene polymorphism in the patients and controls. Results: The analysis of the apoE gene demonstrated a predominance of the e3 allele in both the patients and controls, followed by the e4 and then the e2 alleles. The analysis of the apoE genotype and allele frequencies showed significantly higher e4 allele and E3E4 genotype frequencies and decreased e3 allele and E3E3 genotype frequencies in the patients compared with the controls. The e2, e4 and E3E4 carriers within the ESRD patient population presented an atherogenic lipid profile. However, there were no significant variations in the serum PON activity and the hs-CRP and t-Hcy levels between individuals with different apoE polymorphisms. Conclusions: Our findings suggest an association between the e4 allele, E3E4 genotype and ESRD. The apoE polymorphism affects the serum lipoprotein levels, and the ESRD patients who are e4 and e2 allele carriers are more likely to present an atherogenic lipoprotein profile that may be a major factor associated with increased risk of CVD.