<P> Coronary artery disease has a number of well determined risk factors . These include high blood pressure, smoking, diabetes, lack of exercise, obesity, high blood cholesterol, poor diet, depression, family history, and excessive alcohol . About half of cases are linked to genetics . Smoking and obesity are associated with about 36% and 20% of cases, respectively . Smoking just one cigarette per day about doubles the risk of CAD . Lack of exercise has been linked to 7--12% of cases . Exposure to the herbicide Agent Orange may increase risk . Rheumatologic diseases such as rheumatoid arthritis, systemic lupus erythematosus, psoriasis, and psoriatic arthritis are independent risk factors as well . </P> <P> Job stress appears to play a minor role accounting for about 3% of cases . In one study, women who were free of stress from work life saw an increase in the diameter of their blood vessels, leading to decreased progression of atherosclerosis . In contrast, women who had high levels of work - related stress experienced a decrease in the diameter of their blood vessels and significantly increased disease progression . Having a type A behavior pattern, a group of personality characteristics including time urgency, competitiveness, hostility, and impatience, is linked to an increased risk of coronary disease . </P> <Ul> <Li> High blood cholesterol (specifically, serum LDL concentrations). HDL (high density lipoprotein) has a protective effect over development of coronary artery disease . </Li> <Li> High blood triglycerides may play a role . </Li> <Li> High levels of lipoprotein (a), a compound formed when LDL cholesterol combines with a protein known as apolipoprotein (a). </Li> </Ul> <Li> High blood cholesterol (specifically, serum LDL concentrations). HDL (high density lipoprotein) has a protective effect over development of coronary artery disease . </Li>

Ischemic heart disease is most accurately defined as