All were healthy at the start of the experiment, but 474 of the physicians suffered a first heart attack during the followup. I want to emphasize that such men don't have a disease. They aren't sick or abnormal. Their levels of ICAM-1 merely sit at the high end of the normal range. ICAM-1 gives us insight into exactly what's happening.
Adhesion molecules can pick white cells out of blood as they float by.
These white cells, called monocytes and macrophages, destroy invading microbes like viruses and bacteria. Apparently, there is a harmful side to this healing process. In some people, sticky white cells get stuck between the blood vessel lining and the layer of muscles behind the lining. They start building what are called foam cells, which become collection points for oxidized low-density cholesterol, clumps of blood platelets, decaying muscle cells, fibrous tissue, and even hard calcium deposits. This arterial refuse then causes raised patches, or plaques, that disrupt, then block, flow of blood.