Homocysteine and cognitive function in the Sacramento Area Latino Study on Aging.
BACKGROUND
Elevated plasma homocysteine (hyperhomocysteinemia), an independent risk factor for vascular disease, has been reported to be inversely correlated with objective measures of cognitive function in patients with Alzheimer disease and in community-dwelling older adults.


OBJECTIVE
We evaluated the cross-sectional relation between total plasma homocysteine concentration and cognitive function in elderly Latinos (aged > or = 60 y; n = 1789) participating in the Sacramento Area Latino Study on Aging.


METHODS
Global cognitive function was assessed by using the Modified Mini-Mental State Examination, and specific cognitive functions were assessed by using 6 instruments developed for cross-cultural and multilingual neuropsychological evaluation of older persons. Associations between the cognitive function scores and total plasma homocysteine concentrations were then measured by multiple regression analysis with control for potential confounding by nutrient status (red blood cell folate, plasma vitamin B-12), kidney function (serum creatinine), demographic variables (age, sex, education, acculturation), and depressive symptoms.


RESULTS
Modest inverse associations were found between homocysteine concentrations and several indexes of cognitive function, including the global Modified Mini-Mental State Examination assessment and the picture-association, verbal attention-span, and pattern-recognition tests (P < or = 0.05). Demographic variables, particularly age and education, were more strongly associated with cognitive function scores than was homocysteine.


CONCLUSIONS
Homocysteine is a modest independent predictor of cognitive function in community-dwelling elderly Latinos. Reducing plasma homocysteine concentrations by administering B-vitamin supplements may provide some protection against cognitive decline in this and other elderly populations, but the effect may be limited.
Miller
Joshua W
JW
Department of Medical Pathology, School of Medicine, University of California, Davis, USA. jwmiller@ucdavis.edu
Green
Ralph
R
Ramos
Marisa I
MI
Allen
Lindsay H
LH
Mungas
Dan M
DM
Jagust
William J
WJ
Haan
Mary N
MN
D000367:Age Factors; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002140:California / Q000453:epidemiology; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology* / Q000517:prevention & control; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D006630:Hispanic or Latino; D006710:Homocysteine / Q000097:blood; D006801:Humans; D020138:Hyperhomocysteinemia / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D012737:Sex Factors; D014805:Vitamin B 12 / Q000008:administration & dosage
D015415:Biomarkers; D006710:Homocysteine; D014805:Vitamin B 12