[The link between cholesterol and atherosclerosis: intervention trials]

Intervention trials aimed at influencing the course of atherosclerosis by reducing blood cholesterol levels of two types: some of them evaluate the clinical consequences of atherosclerosis, while the others study the disease itself by means of arteriography. Several trials of the first type have convincingly shown that the incidence of coronary disease decreases after at least 5 years of medicinal treatment. As for direct visualization trials, they seem to indicate that the development of atheromatous lesions can really be delayed, which would confirm the principal mechanism of the benefits observed in the former trials. Other studies, and notably those on secondary prevention, have not yielded positive results, probably because of belated intervention on the course of atherosclerosis and insufficient reduction of blood cholesterol levels. In clinical practice, the implementation of the corresponding measures remains controversial since in these trials the overall mortality rate did not decrease owing to overmortality from non-cardiovascular causes. Nevertheless, the experimental results strongly support the pathogenic role of atherosclerosis, already well documented by numerous studies of other type.