title: Antioxidant micronutrients and risk of rheumatoid arthritis in a cohort of older women.
abstract: The association of antioxidant vitamins and trace elements from foods and supplements with risk of rheumatoid arthritis was evaluated in a prospective cohort study of 29,368 women who were aged 55-69 years at baseline in 1986. Through 1997, 152 cases of rheumatoid arthritis were identified. After controlling for other risk factors, greater intakes (highest tertile vs. lowest) of supplemental vitamin C (relative risk (RR) = 0.70, 95% confidence interval (CI): 0.48, 1.09; p-trend = 0.08) and supplemental vitamin E (RR = 0.72, 95% CI: 0.47, 1.12; p-trend = 0.06) were inversely associated with rheumatoid arthritis. There was no association with total carotenoids, alpha- or beta-carotene, lycopene, or lutein/zeaxanthin, while there was an inverse association with beta-cryptoxanthin (RR = 0.59, 95% CI: 0.39, 0.90; p-trend = 0.01). Greater use of supplemental zinc (RR = 0.39, 95% CI: 0.17, 0.88; p-trend = 0.03) was inversely associated with rheumatoid arthritis, while any use of supplemental copper (RR = 0.54, 95% CI: 0.28, 1.03) and manganese (RR = 0.50, 95% CI: 0.23, 1.07) showed suggestive inverse associations with rheumatoid arthritis. Greater intakes of fruit (RR = 0.72, 95% CI: 0.46, 1.12; p-trend = 0.13) and cruciferous vegetables (RR = 0.65, 95% CI: 0.42, 1.01; p-trend = 0.07) also exhibited trends toward inverse associations with risk. When the antioxidants were modeled together, only beta-cryptoxanthin and supplemental zinc were statistically significant predictors. Intake of certain antioxidant micronutrients, particularly beta-cryptoxanthin and supplemental zinc, and possibly diets high in fruits and cruciferous vegetables, may be protective against the development of rheumatoid arthritis.
authors.affiliation: Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA. cerhan.james@mayo.edu
authors.forename: James R
authors.initials: JR
authors.lastname: Cerhan
authors.forename: Kenneth G
authors.initials: KG
authors.lastname: Saag
authors.forename: Linda A
authors.initials: LA
authors.lastname: Merlino
authors.forename: Ted R
authors.initials: TR
authors.lastname: Mikuls
authors.forename: Lindsey A
authors.initials: LA
authors.lastname: Criswell
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000378:metabolism*; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000453:epidemiology* / Q000209:etiology; D065366:Cryptoxanthins; D004032:Diet; D005260:Female; D006801:Humans; D007484:Iowa / Q000453:epidemiology; D018977:Micronutrients / Q000097:blood*; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D024341:Xanthophylls; D015032:Zinc / Q000097:blood; D019207:beta Carotene / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D000975:Antioxidants; D065366:Cryptoxanthins; D018977:Micronutrients; D024341:Xanthophylls; D019207:beta Carotene; D015032:Zinc