An overview of the quantitative influence of several risk factors on progression of atherosclerosis in young people in the United States. Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group.

This overview of the National Institutes of Health-supported, multicenter, investigator-initiated study of the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) is designed to summarize the plan, approaches, and the expanding contribution of this unique research program, which is now in its tenth year. It traces for the first time the development, the organization, and the function of the many new features and facets that are being used to yield needed information on the relationships between the classic risk factors and the topography, severity, and the cellular and chemical reactions that influence the development of the early raised plaques. It has also helped establish the factors that influence the progression of the four major types of intermediate raised lesions that grossly are all similar, well delineated fatty plaques. Most of the observations are quantitative. A few glimpses into the unique findings that have been published are presented.