CAD is prevalent in diabetic patients. Based on an autopsy study, approximately 50% of diabetic patients under the age of 65 years will have evidence of CAD. In those who are above 65 years, 75% will have established CAD. Diabetes mellitus increases the CAD risk in men by 2 times and women by 4 times,. It accelerates the rate of progression of the disease, causes higher rates of heart attack and heart failure, and a higher incidence of cardiac death compared with non-diabetic patients. The types of CAD in diabetes are also more complex, in that there are: more diffuse stenosis (narrowing), more calcified (hardened) disease, more complete occlusions (blockage) of the diseased blood vessels and multivessel involvement. Diabetic patients also fare worse after treatment with either coronary ballooning and stenting or coronary artery bypass operation compared with non-diabetics.
The exact reasons for this worse CAD state are complex and multifactorial. It is said that persistent elevation of blood glucose changes the lipid profile of the patients, affects normal function of the inner lining of blood vessels(‘endothelial dysfunction’), and triggers more inflammation and increases the tendency to blood clot formation (‘thrombosis’) which causes the heart attack.