Abstract 34: Serum Dietary Antioxidants in Young Adulthood and Incident Cardiovascular Disease in Middle Age: The CARDIA Study

Abstract

Introduction: Serum levels of carotenoids and tocopherols are objective measures of dietary intakes, including fruits and vegetables (carotenoids and the carotenoid index), nuts/seeds and vegetable oils (α-tocopherol (α-toc)), and oils, margarines, salad dressing and other related foods (γ-tocopherol (γ-toc)). Little research has examined these serum measures in young adulthood as predictors of the incidence of cardiovascular disease (CVD) in middle age. Hypothesis: Circulating carotenoids and tocopherols in young adulthood are inversely associated with incident CVD during middle-age. Methods: Participants from the Coronary Artery Risk Development in Young Adults study (CARDIA, N=5,115) with serum measures of carotenoids and tocopherols at year 0 of the study and concurrent risk factor data were included in the analysis (N=4,810, mean age 25). CVD events (n=167, coronary heart disease, stroke, and heart failure, adjudicated based on medical records) were ascertained over 25 years of follow up. Multivariable Poisson regression (PROC Genmod) was used to estimate the incidence density of CVD over 25 years according to quintiles of the carotenoid index (sum of 4 variables, defined in Table), α-toc and γ-toc with adjustment for demographic, lifestyle, and clinical covariates. Results: There was a strong inverse association between higher levels of the carotenoid index and incidence of CVD, a suggestive inverse association between higher levels of α-toc and incident CVD, and a positive association between γ-toc and incident CVD (Table). The carotenoid, lycopene, did not predict incident CVD. Conclusions: The results for the carotenoids and α-tocopherol underscore how a nutrient rich, plant based dietary pattern in young adulthood may inversely associate with CVD events through middle age. The divergent γ-toc results may reflect the kinetics of its metabolism, a poorer dietary pattern, or higher intake of a food from the food supply (e.g. margarine in 1985-6) that may increase risk.