A study of plasma total homocysteine levels in healthy people.

UNLABELLED: Elevated plasma levels of homocysteine have been identified as an independent risk factor for atherosclerosis. AIM: The aim of this study was to determine the reference limits of plasma total homocysteine for Bulgarian population. MATERIALS AND METHODS: We investigated 153 healthy individuals without vitamin deficiency aged from 18 to 65 years. The reference group consisted of 74 males and 79 females with mean age respectively 37.80 +/- 1.36 and 39.32 +/- 1.33 years. Plasma total homocysteine was determined by high performance liquid-chromatography (HPLC) modified and validated in our laboratory. RESULTS: The reference intervals were 7.4-18.5 micromol/l for males and 5.5-14.5 micromol/ 1 for females. The mean levels of plasma homocysteine were significantly higher in males in comparison with females (11.86 +/- 0.33 micromol/l vs. 9.88 +/- 0.27 micromol/l; P < 0.001), without considerable correlation with age. Comparing the values of total homocysteine between the two groups of age - < or = 49 and > or = 50 years showed that the investigated individuals > or = 50 years had higher plasma concentration, and the difference was significant only for the group of females. Hyperhomocysteinemia according to ECAP cut-off value (> 12.1 micromol/l) was registered in 30.7% of healthy volunteers. CONCLUSIONS: The results of our study demonstrated that homocysteine levels depend on sex and, to a lesser degree, on age. We have determined plasma total homocysteine reference intervals for the Bulgarian population. This will help the interpretation of the results and contribute to adequate and efficient prevention of blood vessel diseases.