Relation of the tocopherol forms to incident Alzheimer disease and to cognitive change.
BACKGROUND
High intake of vitamin E from food (tocopherol), but not from supplements (which usually contain alpha-tocopherol), is inversely associated with Alzheimer disease.


OBJECTIVE
We examined whether food intakes of vitamin E, alpha-tocopherol equivalents (a measure of the relative biologic activity of tocopherols and tocotrienols), or individual tocopherols would protect against incident Alzheimer disease and cognitive decline over 6 y in participants of the Chicago Health and Aging Project.


METHODS
The 1993-2002 study of community residents aged >or=65 y included the administration of 4 cognitive tests and clinical evaluations for Alzheimer disease. Dietary assessment was by food-frequency questionnaire.


RESULTS
Tocopherol intake from food was related to the 4-y incidence of Alzheimer disease determined by logistic regression in 1041 participants who were clinically evaluated (n=162 incident cases) and to change in a global cognitive score determined by mixed models in 3718 participants. Higher intakes of vitamin E (relative risk: 0.74 per 5 mg/d increase; 95% CI: 0.62, 0.88) and alpha-tocopherol equivalents (relative risk: 0.56 per 5 mg/d increase; 95% CI: 0.32, 0.98) were associated with a reduced incidence of Alzheimer disease in separate multiple-adjusted models that included intakes of saturated and trans fats and docosahexaenoic acid. alpha- and gamma-Tocopherol had independent associations. In separate mixed models, a slower rate of cognitive decline was associated with intakes of vitamin E, alpha-tocopherol equivalents, and alpha- and gamma-tocopherols.


CONCLUSIONS
The results suggest that various tocopherol forms rather than alpha- tocopherol alone may be important in the vitamin E protective association with Alzheimer disease.
Morris
Martha Clare
MC
Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL 60612, USA. martha_c_morris@rush.edu
Evans
Denis A
DA
Tangney
Christine C
CC
Bienias
Julia L
JL
Wilson
Robert S
RS
Aggarwal
Neelum T
NT
Scherr
Paul A
PA
D000368:Aged; D000544:Alzheimer Disease / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control; D000975:Antioxidants / Q000008:administration & dosage*; D003071:Cognition / Q000187:drug effects*; D016001:Confidence Intervals; D004032:Diet; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D015596:Nutrition Assessment; D012306:Risk; D011795:Surveys and Questionnaires; D024505:Tocopherols / Q000008:administration & dosage* / Q000737:chemistry; D014810:Vitamin E / Q000008:administration & dosage* / Q000031:analogs & derivatives; D024502:alpha-Tocopherol / Q000008:administration & dosage; D024504:gamma-Tocopherol / Q000008:administration & dosage
D000975:Antioxidants; D014810:Vitamin E; D024504:gamma-Tocopherol; D024502:alpha-Tocopherol; D024505:Tocopherols