Comparison of lipid fatty acids on a concentration basis vs weight percentage basis in patients with and without coronary artery disease or diabetes.

Lipid fatty acid compositions are almost always expressed on a weight percentage basis rather than as weight or molar concentrations. With the former method of calculation, each fatty acid has an effect on the composition of the other fatty acids, an interdependence that can potentially lead to inaccurate and misleading results. Here we compare the concentrations per liter and the weight percentage compositions of cholesteryl ester and phospholipid fatty acids in individuals with and without coronary artery disease as well as free fatty acid compositions in individuals with and without diabetes. A new method for quantifying lipid fatty acids is also presented. Fatty acid results expressed as concentrations and those calculated on a weight percentage basis may lead to different conclusions, because significant differences between patient groups can be lost with the latter approach. We conclude that serum concentrations of lipid fatty acids are more accurate reflections of changes in lipid fatty acids than are weight percentage calculations, and are more easily interpreted in metabolic and therapeutic terms.