BACKGROUND AND OBJECTIVES: To investigate the effects of age, sex and vitamin status on total plasma homocysteine (tHCy), both after fasting (FtHCy) and two hours post-methionine load (PML-tHCy). The secondary aim was to determine the reference values for FtHCy and PML-tHCy. DESIGN AND METHODS: A cohort of apparently healthy volunteers underwent blood sampling for FtHCy, PML-tHCy, creatinine, serum folate, vitamin B12 and vitamin B6 (pyridoxal-5-phosphate, PLP). RESULTS: In 147 subjects (M/F= 82/65, age range: 14-94 years), FtHCy was significantly higher in men than in women. In men, age and folate levels explained 20.5% and 19.0% of FtHCy variance, respectively. In women, age and vitamin B12 accounted for 22.6% and 17.8% of FtHCy variance, respectively. PML-tHCy was similar in men and women. PML-tHCy was negatively correlated with folate in both sexes, and with vitamin B12 and age in women only. Folate accounted for 20% of the variance of PML-tHCy in men, while in women vitamin B12 and PLP explained 40% and 20% of variance of PML-tHCy, respectively. The reference values of FtHCy and PML-tHCy were: 19.63 and 40.18 mol/L, respectively, for men under 45 years, 14.26 and 28.31 mol/L, respectively, for women under 45 years, 28.38 and 36.48 mol/L for men above 45 years, and 22.49 and 44.06 mol/L for women above 45 years. INTERPRETATION AND CONCLUSIONS: Age, gender and vitamin status influence both FtHCy and PML-tHCy in normal subjects. Reference values should be calculated according to age and sex.
BACKGROUND AND OBJECTIVES: To investigate the effects of age, sex and vitamin status on total plasma homocysteine (tHCy), both after fasting (FtHCy) and two hours post-methionine load (PML-tHCy). The secondary aim was to determine the reference values for FtHCy and PML-tHCy. DESIGN AND METHODS: A cohort of apparently healthy volunteers underwent blood sampling for FtHCy, PML-tHCy, creatinine, serum folate, vitamin B12 and vitamin B6 (pyridoxal-5-phosphate, PLP). RESULTS: In 147 subjects (M/F= 82/65, age range: 14-94 years), FtHCy was significantly higher in men than in women. In men, age and folate levels explained 20.5% and 19.0% of FtHCy variance, respectively. In women, age and vitamin B12 accounted for 22.6% and 17.8% of FtHCy variance, respectively. PML-tHCy was similar in men and women. PML-tHCy was negatively correlated with folate in both sexes, and with vitamin B12 and age in women only. Folate accounted for 20% of the variance of PML-tHCy in men, while in womenvitamin B12 and PLP explained 40% and 20% of variance of PML-tHCy, respectively. The reference values of FtHCy and PML-tHCy were: 19.63 and 40.18 mol/L, respectively, for men under 45 years, 14.26 and 28.31 mol/L, respectively, for women under 45 years, 28.38 and 36.48 mol/L for men above 45 years, and 22.49 and 44.06 mol/L for women above 45 years. INTERPRETATION AND CONCLUSIONS: Age, gender and vitamin status influence both FtHCy and PML-tHCy in normal subjects. Reference values should be calculated according to age and sex.
Authors: Amy C Keller; Jelena Klawitter; Kerry L Hildreth; Uwe Christians; Kelly Putnam; Wendy M Kohrt; Jane E B Reusch; Kerrie L Moreau Journal: J Appl Physiol (1985) Date: 2019-03-21
Authors: P Katre; S Joshi; D S Bhat; M Deshmukh; N Gurav; S Pandit; H Lubree; S Marczewski; C Bennett; L Gruca; K Kalyanaraman; S S Naik; C S Yajnik; S C Kalhan Journal: Eur J Clin Nutr Date: 2015-09-16 Impact factor: 4.016
Authors: Lise Bathum; Jacob von Bornemann Hjelmborg; Lene Christiansen; Jonna Skov Madsen; Axel Skytthe; Kaare Christensen Journal: Osteoporos Int Date: 2004-01-16 Impact factor: 4.507
Authors: Viktor Komlósi; Erika Hitre; Eva Pap; Vilmos Adleff; Andrea Réti; Eva Székely; Anna Bíró; Péter Rudnai; Bernadette Schoket; Judit Müller; Béla Tóth; Szabolcs Ottó; Miklós Kásler; Judit Kralovánszky; Barna Budai Journal: BMC Cancer Date: 2010-10-04 Impact factor: 4.430
Authors: David J Braun; Erin Abner; Vikas Bakshi; Danielle S Goulding; Elizabeth M Grau; Ai-Ling Lin; Christopher M Norris; Tiffany L Sudduth; Scott J Webster; Donna M Wilcock; Linda J Van Eldik Journal: ASN Neuro Date: 2019 Jan-Dec Impact factor: 4.146