Although personality type has been proposed as a risk factor, its role is controversial. The association of total serum cholesterol and LDL cholesterol levels with the risk of CAD is direct and continuous. HDL levels are inversely correlated with CAD risk. The main causes of reduced HDL are cigarette smoking, obesity, and physical inactivity. The risk associated with hypertension is lower in societies with low average cholesterol levels.
Smoking is particularly hazardous in persons at increased cardiovascular risk.
There is a dose relationship between the risk of CAD and the number of cigarettes smoked daily. Men and women are both susceptible, but the risk for women may be greater. Nicotine and other tobacco-derived chemicals are toxic to vascular endothelium. It also increases platelet reactivity, which may favor platelet thrombus formation, and increases plasma fibrinogen concentration and Hct, resulting in increased blood viscosity. Hyperinsulinemia damages vascular endothelium.