Diabetes is a common chronic medical condition that leads to increased blood sugar (glucose) levels. Severe complications can result from diabetes, including heart disease, vascular (blood vessel) disease and poor circulation, blindness, kidney failure, poor healing, stroke, and other neurological (nerve) diseases. Diabetes cannot be cured but can be successfully treated. Complications from diabetes can be prevented with careful blood glucose management and control of high blood pressure and high cholesterol levels when present. This Patient Page is based on one published in the April 15, 2009, issue of JAMA. The June 22/29, 2011, issue of JAMA includes articles about diabetes.