Interleukin-6 -634 C/G and -174 G/C polymorphisms in Korean patients undergoing hemodialysis

Korean J Intern Med. 2012 Sep;27(3):327-37. doi: 10.3904/kjim.2012.27.3.327. Epub 2012 Sep 1.

Abstract

Background/aims: Chronic inflammatory status is a possible risk factor for vascular access dysfunction in hemodialysis (HD) patients, but susceptibility differences appear among individuals. Interleukin (IL)-6 is a well-known inflammatory cytokine with various polymorphisms. We examined whether IL-6 polymorphisms are associated with vascular access dysfunction in HD patients.

Methods: A total of 80 HD patients (including 42 diabetic patients) were enrolled. Polymorphisms in the IL-6 gene promoter (-634 C/G and -174 G/C) were studied using restriction length polymorphism polymerase chain reaction analysis. Vascular access patency was compared between the patient groups with respect to IL-6 polymorphisms. An additional 89 healthy individuals were enrolled in the control group. Plasma IL-6 levels were determined by enzyme-linked immunosorbent assay.

Results: The GG genotype and G allele at position -634 in the IL-6 promoter were more frequently observed in HD patients than in controls. Furthermore, the distribution of the -634 polymorphism differed according to vascular access patency in non-diabetic HD patients. However, the G allele was not a significant risk factor for early access failure. No significant association appeared between the IL-6 -634 C/G polymorphism and plasma IL-6 levels. The C allele of the IL-6 -174 G/C polymorphism was not detected in our study population.

Conclusions: The IL-6 -634 G allele appears with greater frequently in patients with end-stage renal disease and may be associated with vascular access dysfunction in non-diabetic HD patients.

Keywords: Hemodialysis; Inflammation; Interleukin-6 polymorphism; Vascular access failure.

MeSH terms

  • Adult
  • Aged
  • Arteriovenous Shunt, Surgical / adverse effects*
  • Asian People / genetics*
  • Case-Control Studies
  • Chi-Square Distribution
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Gene Frequency
  • Genotype
  • Graft Occlusion, Vascular / blood
  • Graft Occlusion, Vascular / ethnology
  • Graft Occlusion, Vascular / genetics*
  • Graft Occlusion, Vascular / physiopathology
  • Humans
  • Interleukin-6 / blood
  • Interleukin-6 / genetics*
  • Kidney Failure, Chronic / blood
  • Kidney Failure, Chronic / ethnology
  • Kidney Failure, Chronic / genetics
  • Kidney Failure, Chronic / immunology
  • Kidney Failure, Chronic / therapy*
  • Logistic Models
  • Male
  • Middle Aged
  • Odds Ratio
  • Phenotype
  • Polymerase Chain Reaction
  • Polymorphism, Genetic*
  • Promoter Regions, Genetic
  • Renal Dialysis*
  • Republic of Korea
  • Time Factors
  • Treatment Outcome
  • Vascular Patency / genetics*

Substances

  • IL6 protein, human
  • Interleukin-6