Cigarette Smoking as a Risk Factor for Coronary Artery Disease

Abstract

The epidemiologic evidence linking cigarette smoking to coronary artery disease has been supported by multiple studies over a period of 30 years. Community based cohort studies such as the Framingham study have shown that cigarette smokers are at a markedly elevated risk of developing cardiovascular events. These studies have also shown that former cigarette smokers have a decline in the excess incidence over a period of several years to approach that of non-smoking populations. Uncertainty then appears to exist as to whether cigarette smokers are at increased risk of cardiovascular events solely because of acute effects of smoking or whether cigarette smoking is also a risk factor for atherosclerosis. Evidence that cigarette smoking is a risk factor for atherosclerosis comes from autopsy and cardiac catheterization laboratory. While not all of these studies show a relationship, the data do, for the most part, show a definite relationship between cigarette smoking and atherosclerosis. Catheterization and autopsy studies suffer from biases that prevent application of prediction models to the general population. However, the combined view of the community based, catheterization and autopsy studies supports a unifying hypothesis of acute effects that may lead to cardiovascular events in the setting of established vascular disease as well as vascular damage that may promote the development of atherosclerosis. Cessation of smoking will rapidly remove the acute effects, and may lead to inactivation of acute lesions. The underlying substrate of atherosclerosis and coronary obstructive lesions appears to be correlated with long term cigarette smoking.