Diabetes is a chronic condition in which the body's ability to produce or respond to insulin, a hormone that regulates blood sugar levels, is impaired. Cardiovascular disease refers to conditions affecting the heart and blood vessels, such as coronary artery disease, heart failure, and stroke. When these two conditions are mentioned together, it means there is an increased risk of developing cardiovascular diseases in people with diabetes due to the effects of high blood sugar levels on blood vessels and the heart.