title: Elevated plasma homocysteine level is not primarily related to Alzheimer's disease.
abstract: BACKGROUND
  A moderate elevation of plasma total homocysteine (tHcy) is considered a potential risk factor for Alzheimer's disease (AD).
  
  
  METHODS
  We have investigated the main determinants (age, renal impairment, cobalamin/folate status and the presence of vascular disease) of plasma tHcy in 326 patients with AD, and also in 281 patients with mild cognitive impairment (MCI), since about half of these patients develop AD during the first 5 years.
  
  
  RESULTS
  Elevated plasma tHcy in patients with AD could mainly be attributed to cobalamin/folate deficiency or renal impairment. Younger patients (below 75 years) with AD and patients with MCI without cobalamin/folate deficiency or renal impairment showed normal levels of plasma tHcy.
  
  
  CONCLUSIONS
  Our findings suggest that plasma tHcy is not primarily involved in the pathogenesis of AD but rather a reflection of changes of the main determinants of plasma tHcy in AD patients.
authors.affiliation: Departments of Psychogeriatrics, Clinical Science, Lund University Hospital, Lund, Sweden.
authors.forename: Karin
authors.initials: K
authors.lastname: Nilsson
authors.forename: Lars
authors.initials: L
authors.lastname: Gustafson
authors.forename: Björn
authors.initials: B
authors.lastname: Hultberg
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood; D000544:Alzheimer Disease / Q000097:blood* / Q000150:complications; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000097:blood* / Q000150:complications; D005260:Female; D005492:Folic Acid / Q000097:blood; D005494:Folic Acid Deficiency / Q000150:complications; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000150:complications*; D008297:Male; D008875:Middle Aged; D051437:Renal Insufficiency / Q000150:complications; D012307:Risk Factors; D014652:Vascular Diseases / Q000150:complications; D014805:Vitamin B 12 / Q000097:blood; D014806:Vitamin B 12 Deficiency / Q000150:complications
chemical_list: D006710:Homocysteine; D005492:Folic Acid; D014805:Vitamin B 12