title: Effect of age on plasma homocysteine concentrations in young and elderly subjects considering serum vitamin concentrations and different lifestyle factors.
abstract: OBJECTIVE
  The aim of this study was to investigate whether an increase in total homocysteine (tHcy) concentration with increasing age is due to diminishing serum concentrations of pyridoxal-5-phosphate (PLP), vitamin B-12, and folate. The possible influence of different lifestyle factors on tHcy concentration was considered.
  
  
  METHODS
  Plasma tHcy, serum concentrations of pyridoxal-5-phosphate, vitamin B-12, and folate, intake of coffee and tea, alcohol, and methionine, as well as cigarette smoking, were determined in 252 elderly subjects (60-87 years old) of the longitudinal study on nutrition and health status in an aging population in Giessen (GISELA) and 99 young adults (20-34 years old) of the study on health and nutrition of young adults (GEJE).
  
  
  RESULTS
  Mean plasma tHcy concentrations were significantly higher in elderly than in young female subjects (9.7 +/- 1.9 micromol/L vs. 9.0 +/- 1.6 micromol/L, p < 0.05), but there was no difference between elderly and young men (10.6 +/- 2.1 micromol/L vs. 10.7 +/- 2.6 micromol/L). No differences in tHcy were observed between young and elderly subjects after adjustment for serum concentrations of PLP, vitamin B-12, and folate. Multiple linear regression analysis revealed a significant influence of age only in elderly, but not in younger subjects.
  
  
  CONCLUSIONS
  Higher tHcy concentrations in the elderly, in comparison to younger women, are due to lower serum concentrations of PLP, vitamin B-12, and folate, whereas within the age group of elderly subjects alone tHcy concentrations increase with age irrespective of serum vitamin concentrations.
authors.affiliation: Institute of Nutritional Sciences, Justus Liebig University of Giessen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Strassburg
authors.forename: Carolin
authors.initials: C
authors.lastname: Krems
authors.forename: Petra M
authors.initials: PM
authors.lastname: Lührmann
authors.forename: Bernd
authors.initials: B
authors.lastname: Hartmann
authors.forename: Monika
authors.initials: M
authors.lastname: Neuhäuser-Berthold
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D000428:Alcohol Drinking; D003069:Coffee; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005858:Germany; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008019:Life Style; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008715:Methionine / Q000008:administration & dosage; D008875:Middle Aged; D009752:Nutritional Status; D011732:Pyridoxal Phosphate / Q000097:blood*; D012727:Sex Characteristics; D012907:Smoking; D013662:Tea; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D003069:Coffee; D013662:Tea; D006710:Homocysteine; D011732:Pyridoxal Phosphate; D005492:Folic Acid; D008715:Methionine; D014805:Vitamin B 12