Plasma homocysteine, methylenetetrahydrofolate reductase gene polymorphism and carotid intima-media thickness in Italian type 2 diabetic patients

Eur J Clin Invest. 2002 Jan;32(1):24-8. doi: 10.1046/j.1365-2362.2002.00936.x.


Background: Moderately elevated levels of homocysteine have been associated with an increased cardiovascular risk in type 2 diabetic patients. The role of methylenetetrahydrofolate reductase gene polymorphism is less clear.

Materials and methods: We investigated the contribution of plasma homocysteine levels and the methylenetetrahydrofolate reductase gene polymorphism to the variability of carotid intima-media thickness in 124 consecutive Italian patients with type 2 diabetes mellitus. Fasting plasma homocysteine was measured by high-pressure liquid chromatography with an electrochemical detector; methylenetetrahydrofolate reductase genotypes were determined by polymerase chain reaction and restriction enzyme digestion. The carotid intima-media thickness was evaluated with high-resolution B-mode ultrasonography.

Results: Age, creatinine and plasma homocysteine levels showed a positive correlation with mean carotid intima-media thickness values, but only age and creatinine levels were still associated with mean carotid intima-media thickness values in the multivariate analysis. Plasma homocysteine levels were significantly higher in the patients bearing the 677T/677T genotype of the methylenetetrahydrofolate reductase polymorphism; mean carotid intima-media thickness values were not different in the three different methylenetetrahydrofolate reductase genotypes.

Conclusion: In 124 Italian patients with type 2 diabetes mellitus, basal levels of plasma homocysteine, as well as methylenetetrahydrofolate reductase gene polymorphism, did not explain the variability of mean carotid intima-media thickness.

MeSH terms

  • Aged
  • Carotid Arteries / diagnostic imaging
  • Carotid Arteries / pathology*
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / epidemiology
  • Diabetes Mellitus, Type 2 / genetics
  • Diabetes Mellitus, Type 2 / pathology*
  • Diabetic Angiopathies / blood
  • Diabetic Angiopathies / epidemiology
  • Diabetic Angiopathies / genetics
  • Diabetic Angiopathies / pathology
  • Female
  • Genotype
  • Homocysteine / blood*
  • Humans
  • Italy
  • Male
  • Methylenetetrahydrofolate Reductase (NADPH2)
  • Middle Aged
  • Oxidoreductases Acting on CH-NH Group Donors / genetics*
  • Polymorphism, Single Nucleotide*
  • Prevalence
  • Risk Factors
  • Tunica Intima / pathology
  • Ultrasonography


  • Homocysteine
  • Oxidoreductases Acting on CH-NH Group Donors
  • Methylenetetrahydrofolate Reductase (NADPH2)