Association of Postprandial Triglyceride and Retinyl Palmitate Responses With Newly Diagnosed Exercise-induced Myocardial Ischemia in Middle-aged Men and Women

BACKGROUND:

Fatty diets are a likely cause of atherosclerosis, and lipoproteins appearing in blood after a fatty meal may be particularly atherogenic. Yet nearly all published research up to 1990 on the relationship of blood lipids to atherosclerosis in humans measured lipids only in fasting or casual samples.

The atherogenicity of postprandial lipoproteins, particularly remnants of triglyceride-rich particles, was suggested by in vitro studies of foam cell induction, feeding experiments in animals, and observations of Type III hyperlipoproteinemia in humans. Indirect evidence for the hypothesis arose from research on conditions characterized by high fasting triglycerides and low HDL-cholesterol, denser LDL particles, and elevations of apolipoprotein B or intermediate-density lipoproteins. The hypothesis received direct support from two small studies by Krauss in 1987 and Simons in 1987 which showed higher postprandial chylomicron remnant concentrations in coronary patients than controls. However, neither study had the statistical power to evaluate the relative associations of fasting and postprandial measurements with disease. Such an evaluation, because of close correlations between fasting and postprandial lipoproteins, required studies with large sample sizes.

The initiative originated in the Division of Epidemiology and Clinical Applications with input from the Division of Heart and Vascular Diseases and the two Divisions' Advisory Groups and was approved in May 1989 by the National Heart, Lung, and Blood Advisory Council. The Request for Applications was released in September 1989. Awards were made in July 1990.

DESIGN NARRATIVE: