Dietary intake of antioxidant nutrients and the risk of incident Alzheimer disease in a biracial community study.
BACKGROUND
Oxidative processes have been suggested as elements in the development of Alzheimer disease (AD), but whether dietary intake of vitamin E and other antioxidant nutrients prevents its development is unknown.


OBJECTIVE
To examine whether intake of antioxidant nutrients, vitamin E, vitamin C, and beta carotene is associated with incident AD.


METHODS
Prospective study, conducted from 1993 to 2000, of individuals selected in a stratified random sample of community-dwelling residents. The 815 residents 65 years and older were free of AD at baseline and were followed up for a mean of 3.9 years. They completed food frequency questionnaires an average of 1.7 years after baseline.


METHODS
Incident AD diagnosed in clinical evaluations with standardized criteria.


RESULTS
Increasing vitamin E intake from foods was associated with decreased risk of developing AD after adjustment for age, education, sex, race, APOE epsilon 4, and length of follow-up. Relative risks (95% confidence intervals [CIs]) from lowest to highest quintiles of intake were 1.00, 0.71 (0.24-2.07), 0.62 (0.26-1.45), 0.71 (0.27-1.88), and 0.30 (0.10-0.92) (P for trend =.05). The protective association of vitamin E was observed only among persons who were APOE epsilon 4 negative. Adjustment for other dietary factors reduced the protective association. After adjustment for baseline memory score, the risk was 0.36 (95% CI, 0.11-1.17). Intake of vitamin C, beta carotene, and vitamin E from supplements was not significantly associated with risk of AD.


CONCLUSIONS
This study suggests that vitamin E from food, but not other antioxidants, may be associated with a reduced risk of AD. Unexpectedly, this association was observed only among individuals without the APOE epsilon 4 allele.
Morris
Martha Clare
MC
Rush Institute for Healthy Aging, Rush-Presbyterian-St Luke's Medical Center, 1645 W Jackson, Suite 675, Chicago, IL 60612, USA. mmorris@rush.edu
Evans
Denis A
DA
Bienias
Julia L
JL
Tangney
Christine C
CC
Bennett
David A
DA
Aggarwal
Neelum
N
Wilson
Robert S
RS
Scherr
Paul A
PA
D000368:Aged; D000544:Alzheimer Disease / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics; D001205:Ascorbic Acid / Q000378:metabolism / Q000494:pharmacology; D044383:Black People / Q000235:genetics; D016000:Cluster Analysis; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D015233:Models, Statistical; D015596:Nutrition Assessment; D018384:Oxidative Stress; D011446:Prospective Studies; D012306:Risk; D014810:Vitamin E / Q000378:metabolism / Q000494:pharmacology; D044465:White People / Q000235:genetics; D019207:beta Carotene / Q000378:metabolism / Q000494:pharmacology
D000975:Antioxidants; D053327:Apolipoprotein E4; D001057:Apolipoproteins E; D019207:beta Carotene; D014810:Vitamin E; D001205:Ascorbic Acid