Abstract P398: Dietary Lipophilic Index and Lipophilic Load and Risk of Coronary Heart Disease in US Men and Women
Background: The lipophilicity of fatty acids may play a role in the etiology of coronary heart disease (CHD) through multiple pathways, including effects on blood lipids, inflammation and thromboembolism. However, conventional classifications of fatty acids by number of double bonds (saturated, monounsaturated and polyunsaturated) and configurations (trans or cis) may not adequately capture the lipophilic properties of all individual fatty acids. We aimed to develop a novel index of dietary fatty acid lipophilicity and evaluate its association with incident CHD in US men and women.
Methods: We followed 74,138 women from the Nurses’ Health Study (1984-2008), and 43,932 men from the Health Professionals Follow-up Study (1986-2008), who were free of CHD, stroke, diabetes, and cancers at baseline. Dietary lipophilic load (LL) was computed by summing the products of intakes of fatty acids (g/d) and melting points of each fatty acids (°C). Dietary lipophilic index (LI) was calculated as dietary LL divided by intakes of total fatty acids. Intakes of dietary fatty acids were derived from food frequency questionnaire (FFQ), which is updated every four years. The study outcome was incident CHD occurred between return of baseline FFQ and January 31, 2008 in men or June 30, 2008 in women. In both cohorts, the occurrence of CHD was updated by biennial follow-up questionnaires. The relative risks (RRs) of incident CHD were estimated by Cox proportional hazards regression.
Results: Dietary LI was observed to be associated with higher intakes of saturated fat and trans fat, and lower intakes of polyunsaturated fat in both men and women. During a total of 2,483,246 person-years of follow-up, we identified 7,188 incident cases of CHD. After multivariate adjustment for age, smoking, physical activity, body mass index, and other CHD risk factors including glycemic load, dietary cereal fiber, fruit and vegetable, a higher dietary LI was significantly associated with an increased risk of total CHD: RR was 1.11 (95% confidence interval [CI] 1.00, 1.23; P for trend = 0.02) for men, and 1.14 (95% CI 1.02, 1.28; P for trend = 0.03) for women, comparing the extreme quintiles of dietary LI. Dietary LL was associated with an increased risk of CHD in women (RR 1.15; 95% CI 1.00-1.33; P=0.03 for trend), but not in men (RR 1.03; 95% CI 0.90-1.19; P=0.63 for trend) comparing extreme quintiles. However, all the associations were largely attenuated after further adjustment for saturated fat, polyunsaturated fat, and trans fat, or polyunsaturated to saturated fat ratio.
Conclusions: These observations suggest that a higher dietary lipophilicity is associated with a modestly increased risk of CHD.
- © 2013 by American Heart Association, Inc.