Objectives: To examine associations between serum antioxidant levels and mortality (all-cause, cancer, and cardiovascular disease (CVD)) among U.S. adults. Design: We examined the risk of death from all-cause and cause-specific mortality associated with serum antioxidant (vitamin E and carotenoids) and vitamin A levels using Cox regression models to estimate hazards ratios (HR) and 95% confidence intervals (CIs). Setting: The National Health and Nutrition Examination Survey (NHANES) 1999-2002 were follow-up through December 31, 2015. Participants: The NHANES 1999-2002 cohort included 8,758 participants aged =20 years. Serum carotenoid levels were only assessed for the 1999-2000 cycle. Therefore, sample size for each assessed antioxidant ranged from 4,633 to 8,758. Results: Serum vitamin E level was positively associated with all-cause mortality (HR= 1.22, 95% CI: 1.04, 1.43, highest vs. lowest quartile). No other antioxidants were associated with mortality in overall analysis. In race/ethnicity-specific analyses, high vitamin E and a-Tocopherol levels were associated with increased risk of all-cause mortality among non-Hispanic Whites. Among non-Hispanic Blacks, serum a-Tocopherol level was associated with decreased risk of cancer mortality (HR= 0.30, 95% CI: 0.12-0.75, third vs. first quartile), and total carotenoids levels with reduced risk of CVD mortality (HR=0.26; 95% CI: 0.07, 0.97, second vs. lowest quartile). Hispanics with high ß-carotene levels had reduced risk of CVD mortality. Conclusions: Serum antioxidant levels may be related to mortality; these associations may differ by race/ethnicity and appeared to be non-linear for all-cause and cause-specific mortality. Further studies are needed to confirm our results.
- Antioxidant micronutrients
- cardiovascular disease