Search

Background: Folate and cobalamin are responsible for healthy growth. However, the B-vitamin and homocysteine status of adolescents is not well known. The aim was to assess the status of folate, cobalamin, and homocysteine in healthy Spanish adolescents., Methods: Serum cobalamin, serum folate, homocysteine, methylenetetrahydrofolate reductase 677C>T variant, BMI, smoking habits, and Tanner stage were determined according to gender in 165 adolescents (84 females, 81 males; 13-18.5 years) using the Student's t test, Mann-Whitney U test and chi(2) test, respectively. Interactions between socioeconomic status, age group, methylenetetrahydrofolate reductase polymorphism, BMI, smoking habits, Tanner stage, and vitamin status, respectively, were examined by ANOVA or Kruskal-Wallis H test (p < 0.05)., Results: Boys had markedly higher homocysteine (males 8.92 (5.51-22.94) micromol/l; females 7.91 (5.09-13.86) micromol/l), whereas girls showed higher serum cobalamin concentrations (males 540.00 (268.00-946.47) pmol/l; females 594.82 (280.63-1,559.64) pmol/l). Data are shown as medians and the 2.5th to 97.5th percentiles in parentheses. Adolescents with the homozygous variant of methylenetetrahydrofolate reductase displayed significantly higher homocysteine and lower serum folate: normal 5.73 (3.09-10.73) ng/ml serum folate, 7.57 (4.94-12.94) micromol/l homocysteine; homozygous 4.10 (2.75-7.88) ng/ml serum folate, 10.83 (7.00-22.82) micromol/l homocysteine., Conclusion: The present study provides data on the folate, cobalamin, and homocysteine status of Spanish adolescents. To assure a better assessment, revision of references for adolescents is still needed., (2008 S. Karger AG, Basel.)

Background: Hyperhomocysteinemia is an accepted risk factor for cardiovascular disease, and possibly also for cognitive impairment and dementia. It has also been proposed as a marker for the status of the B vitamins, which participate in the metabolism of homocysteine. Therefore, especially in the elderly, it is important to know the prevalence of high homocysteine (tHcy) levels and the influence that B vitamins have on them., Material and Methods: 218 elderly of both sexes, aged 60-105, living in an elderly home in Granada (Spain), were screened for serum folate, red blood cell (RBC) folate, serum cobalamin (B12) (Abbott, IMx), holotranscobalamin II (Holo-TC II) (HoloTC RIA, Axis-Shield), methylmalonic acid (MMA) (MS-GC), total pyridoxine (B6) (HPLC), and total homocysteine (tHcy) (Abbott, IMx)., Results: Hyperhomocysteinemia (tHcy >12 pmol/L) was detected in 80.7%. Serum folate deficiency was severe (< or =4 ng/mL) in 19.3% and moderate (4-7 ng/mL) in 43.1%. In 14.2% of the elderly RBC folate was < or =175 ng/mL, and in 61.0% it was between 175-400 ng/mL. Vitamin B12, measured in serum (< or =200 pg/mL), was deficient in 15.8%, but if measured as Holo-TC II (< or =45 pmol/L), deficiency ranged up to 39.1%. MMA was high (> or =300 nmol/L) in 45.6%. Vitamin B6 (< 20 nmol/L) was low only in one person. In order to identify the factors that could predict tHcy levels, a multiple regression analysis was performed. Best results corresponded to the combination of log serum folate and log Holo-TC II, which gave values of R > 0.5. If analyzed independently, the highest correlation was with log serum folate (r = -0.290), followed by RBC folate (r = -0.263), Holo-TC II (r = -0.228), log B12 (r = -0.175), and log B6 (r = -0.078)., Conclusion: There is a high prevalence of vitamin B deficiency and hyperhomocysteinemia in the studied population. Our data confirm the influence of these vitamins, especially folate, on tHcy levels, but hyperhomocysteinemia cannot be used as the only diagnostic criterion to detect subclinical vitamin deficiency in elderly people, especially to detect vitamin B12 deficiency.