Total plasma homocysteine in Bulgarian population measured by high-performance liquid chromatography with fluorescence detection--comparison with fluorescence polarization immunoassay.

Over the last decade, evidence has accumulated that elevated total homocysteine (tHcy) is an independent risk factor for vascular disease. Due to the variety of Hcy determinants (age, gender, ethnicity and lifestyle), it is now recommended that the distribution of plasma Hcy concentrations should be established for different populations. Therefore the objective of our study was to evaluate a modified HPLC with fluorescence detection procedure for reliable quantification of tHcy and to demonstrate its successful application to determine the distribution of tHcy levels in healthy Bulgarians. The presented method showed good analytical performance (intra- and interassay CVs were <3.9% and <6.7%, respectively; inaccuracy was <6.5%, and analytical recovery 95%-98%, the detection limit was 0.3 micromol/l) and no drug interference was registered. Comparison between HPLC-FD and FPIA using Passing-Bablok regression analysis (r=0.9906) showed good agreement. We describe the distribution of plasma tHcy in a group of 162 healthy Bulgarian adults and examined its relation with age and gender. Our results indicate that higher Hcy concentrations were associated with male sex and increasing age. The higher plasma Hcy observed in our population compared to the rest of Europe corresponds to the high prevalence and mortality of cardiovascular disease in Bulgaria.

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.