title: Vitamin E intake and risk of amyotrophic lateral sclerosis: a pooled analysis of data from 5 prospective cohort studies.
abstract: The authors investigated whether vitamin E intake was associated with amyotrophic lateral sclerosis (ALS) in the Nurses' Health Study (1976-2004), the Health Professionals Follow-up Study (1986-2004), the Cancer Prevention Study II Nutrition Cohort (1992-2004), the Multiethnic Cohort Study (1993-2005), and the National Institutes of Health-AARP Diet and Health Study (1995-2005). ALS deaths were identified through the National Death Index. In the Nurses' Health Study and the Health Professionals Follow-up Study, confirmed nonfatal ALS cases were also included. Cohort-specific results were estimated using Cox proportional hazards models and pooled using random-effects models. Among 1,055,546 participants, 805 developed ALS. Overall, using vitamin E supplements was not associated with ALS. However, within cohorts with information on duration of vitamin E supplement use (231 cases), ALS rates declined with increasing years of use (P-trend=0.01). Compared with nonusers, the multivariable-adjusted relative risk was 1.05 (95% confidence interval (CI): 0.60, 1.84) among users for ≤1 year (12 cases), 0.77 (95% CI: 0.33, 1.77) among users for 2-4 years (7 cases), and 0.64 (95% CI: 0.39, 1.04) among users for ≥5 years (18 cases). For dietary vitamin E intake, the multivariable-adjusted relative risk comparing the highest quartile with the lowest was 0.79 (95% CI: 0.61, 1.03); an inverse dose-response was evident in women (P-trend=0.002) but not in men (P-trend=0.71). In this large, pooled prospective study, long-term vitamin E supplement use was associated with lower ALS rates. A possible protective effect of vitamin E deserves further consideration.
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Éilis J
authors.initials: ÉJ
authors.lastname: O'Reilly
authors.forename: Marc G
authors.initials: MG
authors.lastname: Weisskopf
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Logroscino
authors.forename: Marjorie L
authors.initials: ML
authors.lastname: McCullough
authors.forename: Arthur
authors.initials: A
authors.lastname: Schatzkin
authors.forename: Laurence N
authors.initials: LN
authors.lastname: Kolonel
authors.forename: Alberto
authors.initials: A
authors.lastname: Ascherio
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000209:etiology*; D000975:Antioxidants / Q000502:physiology; D004032:Diet; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014810:Vitamin E / Q000502:physiology; D014811:Vitamin E Deficiency / Q000150:complications*
chemical_list: D000975:Antioxidants; D014810:Vitamin E