title: Association between serum homocysteine, vitamin B12, folate and Thai coronary artery disease patients.
abstract: BACKGROUND
  Homocysteine is an intermediate compound formed during metabolism of methionine. The plasma level of homocysteine is dependent on the genetically regulated level of essential enzymes and the intake of folic acid, vitamin B6 (pyridoxine), and vitamin B12 (cobalamine). Elevated serum homocysteine levels are a known risk factor for coronary artery disease (CAD). To establish the magnitude of the CAD that is associated with an increased serum homocysteine level, we compared CAD patients with normal healthy Thai controls.
  
  
  METHODS
  In a cross-sectional study design we investigated the association between serum homocysteine, vitamin B12 and folate levels and the coronary heart disease in 178 CAD patients and 178 normal healthy controls by age and sex matching. These comprised 266 men and 90 women, mean age 58 +/- 10 years for normal controls and 60 +/- 10 years for CAD patients. Serum homocysteine, vitamin B12 and folate were measured by ELISA method and electrochemiluminescense method respectively.
  
  
  RESULTS
  Paired t-test analysis showed that serum homocysteine concentrations were significantly higher in CAD patients (23.83 +/- 11.29 mumol/L) than in control subjects (19.69 +/- 8.51 mumol/L; p < 0.001). Homocysteine levels were also higher in males than in females. These findings were similar in healthy controls (male: 20.37 +/- 8.5 mumol/L, female: 17.77 +/- 8.2 mumol/L, p < 0.05) and in CAD patients (male: 24.91 +/- 11.8 mumol/L, female: 20.73 +/- 8.9 mumol/L, p < 0.05). Homocysteine above 17 mumol/L occurred more common in CAD patients than in control groups (OR = 1.65, 95% CI = 1.09-2.52, p = 0.0249). Low levels of vitamin B12 and folate did not reaching statistical significance when comparing controls and CAD patients.
  
  
  CONCLUSIONS
  Serum homocysteine concentrations were significantly higher in CAD patients than in controls. Serum vitamin B12 and serum folate levels were not statistically significantly different between CAD patients and control groups. The data also demonstrated that the serum homocysteine level is almost always higher in men than in women as previously reported. Although serum vitamin B12 and serum folate levels were not below the upper limit of normal, vitamin B12 and folic acid treatment may reduce serum homocysteine concentrations in CAD patients. We hope that the reversible risk factors will be concern to clinicians for the reduction in the risk of myocardial infarction.
authors.affiliation: Department of Clinical Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: W
authors.initials: W
authors.lastname: Leowattana
authors.forename: N
authors.initials: N
authors.lastname: Mahanonda
authors.forename: K
authors.initials: K
authors.lastname: Bhuripunyo
authors.forename: S
authors.initials: S
authors.lastname: Pokum
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D003327:Coronary Disease / Q000097:blood* / Q000175:diagnosis; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011624:Pteroylpolyglutamic Acids / Q000097:blood*; D012016:Reference Values; D012680:Sensitivity and Specificity; D013785:Thailand; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D015415:Biomarkers; D011624:Pteroylpolyglutamic Acids; D006710:Homocysteine; D014805:Vitamin B 12