title: Tissue omega-6/omega-3 fatty acid ratio and risk for coronary artery disease.
abstract: A ratio that estimates tissue proportions of omega-6 fatty acids (linoleic acid and/or arachidonic acid [AA]) and omega-3 fatty acids (eicosapentaenoic acid [EPA], docosahexaenoic acid [DHA], and/or alpha-linolenic acid) has been proposed as a biomarker of risk for coronary artery disease (CAD). Use of an omega-6/omega-3 fatty acid ratio instead of either fatty acid class alone is based on theoretical reasons and has not been validated. The relationship between risk for CAD events and tissue omega-3 and omega-6 fatty acid composition was evaluated by pooling data from case-control or prospective cohort studies that examined the risk for CAD end points as a function of tissue fatty acid composition. Thirteen studies were included, 11 case-control and 2 prospective cohort studies, and case-control differences in computed averages of several fatty acids and fatty acid ratios were compared. The largest and most consistent difference was for the sum of EPA + DHA (-11% in cases, p = 0.002). Proportions of EPA, DHA, and AA were about 8% lower in cases, but none of these differences was significant. Total omega-3 and omega-6 fatty acids were lower by 7% and 4%, respectively, in cases versus controls, but only the total omega-3 fatty acid difference was significant. The AA/EPA ratio was nonsignificantly lower by 10% in cases. Fatty acid ratios generally failed to distinguish cases from controls, and any discriminatory power they had derived from the omega-3 fatty acid component. Tissue EPA + DHA appears to be the best fatty acid metric for evaluating for CAD risk.
authors.affiliation: Department of Medicine, Mid America Heart Institute of Saint Luke's Health System, Kansas City, Missouri, USA. bill.harris@usd.edu
authors.forename: William S
authors.initials: WS
authors.lastname: Harris
authors.forename: Basel
authors.initials: B
authors.lastname: Assaad
authors.forename: W Carlos
authors.initials: WC
authors.lastname: Poston
mesh_terms: D050154:Adiposity; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000453:epidemiology* / Q000378:metabolism* / Q000503:physiopathology / Q000517:prevention & control; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000378:metabolism* / Q000592:standards; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage / Q000378:metabolism* / Q000592:standards; D006801:Humans; D018673:Nutrition Policy; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D014481:United States / Q000453:epidemiology
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6