Dietary folate and vitamins B-12 and B-6 not associated with incident Alzheimer's disease.
BACKGROUND
It is currently not known whether dietary intakes of folate and vitamins B12 and B6, co-factors in the methylation of homocysteine, protect against Alzheimer's disease.


OBJECTIVE
To examine the association between risk of incident Alzheimer's disease and dietary intakes of folate, vitamin B-12, and vitamin B-6.


METHODS
Prospective cohort study.


METHODS
Geographically defined biracial Chicago community.


METHODS
1,041 residents, aged 65 years and older, initially free of Alzheimer's disease and followed a median 3.9 years for the development of incident disease.


METHODS
Probable Alzheimer's disease identified through structured clinical neurological evaluation using standardized criteria.


RESULTS
A total of 162 persons developed incident Alzheimer's disease during follow-up. In logistic regression models adjusted for age, sex, race, education, cognitive activities, APOE-epsilon4, and dietary intakes of vitamin E in food and total niacin, there was no association between risk of developing Alzheimer's disease and quintiles of folate intake or of vitamin B-12 intake. The adjusted odds ratio was 1.6 (95% confidence interval: 0.5, 5.2) for persons in the highest quintile of total folate intake (median of 752.7 microg/d) compared with persons in the lowest quintile of intake (median, 202.8 microg/d). Compared with persons in the first quintile of total vitamin B-12 intake (median, 3.1 microg/d) the odds ratio was 0.6 (95% confidence interval: 0.2, 1.6) for persons in the fifth quintile of intake (median, 20.6 microg/d). Intake of vitamin B-6 was not associated with incident Alzheimer's disease after control for dietary intakes of vitamin E and total niacin.


CONCLUSIONS
Dietary intakes of folate, vitamin B-12, or vitamin B-6 do not appear to be associated with the development of Alzheimer's disease.
Morris
Martha Clare
MC
Rush Institute for Healthy Aging, Rush University Medical Center, 1645 W. Jackson #675, Chicago, IL 60612, USA. Martha.C.morris@rush.edu
Evans
Denis A
DA
Schneider
Julie A
JA
Tangney
Christine C
CC
Bienias
Julia L
JL
Aggarwal
Neelum T
NT
D000368:Aged; D000375:Aging / Q000502:physiology; D000544:Alzheimer Disease / Q000453:epidemiology / Q000378:metabolism*; D015331:Cohort Studies; D004032:Diet; D019587:Dietary Supplements / Q000706:statistics & numerical data*; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D006801:Humans; D015994:Incidence; D008297:Male; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D014805:Vitamin B 12 / Q000008:administration & dosage*; D025101:Vitamin B 6 / Q000008:administration & dosage*
D025101:Vitamin B 6; D005492:Folic Acid; D014805:Vitamin B 12