Association Between Serum Homocysteine, Vitamin B12, Folate and Thai Coronary Artery Diseatie Patients
WATT ANA LEOWATTANA, M.D.*, KIERTUAI BHURIPUNYO, M.D.**, NITHI MAHANONDA, M.D.**, SASIKANT POKUM, B.Sc. *
Affiliation : * Department of Clinical Pathology, ** Her Majesty's Cardiac Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Background : Homocysteine is an intennediate compound fonned 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 (cobala-
mine). 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 homo-
cysteine level, we compared CAD patients with nonnal healthy Thai controls.
Method : In a cross-sectional study design we investigated the association between serum
homocysteine, vitamin B 12 and folate levels and the coronary heart disease in 178 CAD patients
and 178 nonnal healthy controls by age and sex matching. These comprised 266 men and 90
women, mean age 58 ± 10 years for nonnal controls and 60 ± 10 years for. CAD patients. Serum
homocysteine, vitamin B 12 and folate were measured by ELISA method and electrochemilu-
minescense method respectively.
Results : Paired t-test analysis showed that serum homocysteine concentrations were
significantly higher in CAD patients (23.83±11.29 J..11110IIL) than in control subjects (19.69±8.51
flmol!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 J..11110IIL, female: 17.77 ± 8.2 f.!mol/L,
p < 0.05) and in CAD patients (male: 24.91 ± 11.8 J..11110IIL, female: 20.73 ± 8.9 flmol/L, p < 0.05).
Homocysteine above 17 J..11110IIL 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 B 12 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 B 12 and serum folate levels were not statistically sig-
nificantly 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 B 12 and serum folate levels were not below the upper limit of normal, vitamin B 12 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.
Keywords : Homocysteine, B 12, Folate, CAD Patients
