Britannica Sources used in this answer

How can high blood sugar damage artery walls?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

The role of coronary artery disease in heart attack — cardiovascular disease This micrograph shows a cross section of a coronary artery narrowed by an atherosclerotic plaque (purplish matter inside the artery). Most heart attacks are caused by the rupture of an atherosclerotic plaque, which triggers the formation of a clot that abruptly blocks blood flow to part of the heart muscle.

High blood sugar, or hyperglycemia, contributes to cardiovascular disease primarily by accelerating vascular damage. In large arteries, high blood sugar is associated with the development and rapid progression of atherosclerosis, a condition where plaque builds up in the vessel walls. This process increases the risk of serious events such as myocardial infarction and stroke.1

In smaller arteries and capillaries, chronic high blood sugar leads to microangiopathy, which involves the thickening of vessel walls. This structural change initially makes the vessels abnormally permeable, or "leaky," and eventually renders them prone to obstruction through thrombosis or embolism. These vascular complications are often compounded by other factors common in diabetic patients, such as hypertension and elevated serum lipids. Managing blood glucose levels is essential for slowing or preventing these damaging processes in small vessels.1