title: Homocysteine and cognitive function in a population-based study of older adults.
abstract: OBJECTIVE
  To assess the relations between homocysteine levels and neurobehavioral test scores representing a broad range of cognitive domains in a population-based study of older adults.
  
  
  METHODS
  Cross-sectional analysis of first-visit data of subjects in the Baltimore Memory Study, a longitudinal study.
  
  
  METHODS
  Specific neighborhoods in Baltimore.
  
  
  METHODS
  Participants were 1,140 randomly selected residents aged 50 to 70 with a mean age+/-standard deviation of 59.3+/-5.9; 65.9% were female, and 54.2% were white and 41.1% African-American.
  
  
  METHODS
  Twenty neurobehavioral test scores in eight cognitive domains.
  
  
  RESULTS
  Linear regression models revealed that homocysteine was consistently and strongly associated with worse neurobehavioral test performance, in crude analysis and after control for a large set of important covariates. Associations were observed in all eight cognitive domains assessed but were strongest and most consistent in the domains of simple motor and psychomotor speed, eye-hand coordination/manual dexterity, and verbal memory and learning. On average, an increase in homocysteine levels from the 25th to the 75th percentile, all in the generally accepted normal range, was equivalent in its association with neurobehavioral test scores to an increase of 4.2 years of age. Logistic regression models revealed that, on average, for the neurobehavioral tests associated with homocysteine, subjects in the highest quartile of homocysteine levels were more than two times as likely to be in the lowest quartile of neurobehavioral test scores as those in the lowest quartile.
  
  
  CONCLUSIONS
  Higher homocysteine levels were associated with worse function across a broad range of cognitive domains, and the magnitude of the associations was large. The data suggest that homocysteine may be a potentially important modifiable cause of cognitive dysfunction.
authors.affiliation: Department of Environmental Health Sciences, Division of Occupational and Environmental Health, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Jyme H
authors.initials: JH
authors.lastname: Schafer
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Glass
authors.forename: Karen I
authors.initials: KI
authors.lastname: Bolla
authors.forename: Margaret
authors.initials: M
authors.lastname: Mintz
authors.forename: Anne E
authors.initials: AE
authors.lastname: Jedlicka
authors.forename: Brian S
authors.initials: BS
authors.lastname: Schwartz
mesh_terms: D000368:Aged; D015142:Baltimore; D003071:Cognition; D003430:Cross-Sectional Studies; D005260:Female; D005853:Geriatrics; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008568:Memory; D008875:Middle Aged; D011597:Psychomotor Performance
chemical_list: D006710:Homocysteine