SERUM FATTY-ACIDS AND THE RISK OF CORONARY HEART-DISEASE

To examine the relation between serum fatty acids and coronary heart d isease (CHD), the authors conducted a nested case-control study of 94 men with incident CHD and 94 men without incident CHD who were enrolle d in the Usual Care group of the Multiple Risk Factor Intervention Tri al between December 1973 and February 1976. After confirming the stabi lity of the stored serum samples, the authors measured serum fatty aci d levels by gas-liquid chromatography and examined their association w ith CHD. In all multivariate models, levels of the cholesterol ester s aturated fatty acid palmitic acid (16:0) were directly associated with CHD risk (standardized odds ratio = 1.68; 95% confidence interval 1.1 0-2.55 in the model that adjusted for total plasma cholesterol level). Levels of the phospholipid omega-3 fatty acid docosapentaenoic acid ( 22:5) were inversely associated with CHD risk in the two multivariate models that controlled for the effects of total plasma cholesterol lev el or high density lipoprotein cholesterol to total plasma cholesterol ratio (standardized odds ratio = 0.58; 95% confidence interval 0.38-0 .89 in the first model that controlled for total plasma cholesterol le vel). in contrast to the first two multivariate models, levels of the docosahexaenoic acid (22:6) were inversely associated with CHD risk in a third multivariate model that controlled for the effects of high de nsity lipoprotein cholesterol to low density lipoprotein cholesterol r atio (standardized odds ratio = 0.57; 95% confidence interval 0.36-0.9 0). These findings are consistent with other evidence indicating that saturated fatty acids are directly correlated with CHD and that omega- 3 polyunsaturated fatty acids are inversely correlated with CHD. Becau se these associations were present after adjustment for blood lipid le vels, other mechanisms, such as a direct effect on blood clotting, may be involved.