Many studies have shown a link between elevated glucose levels and cardiovascular disease. It is thought that elevated blood glucose levels trigger a vicious cycle of events resulting in micro and macrovascular complications. Macrovascular complications are apparent at blood glucose levels lower than those that define diabetes. Tight glucose control benefits the cardiovascular system in many ways; however, the evidence that lowering blood glucose can reduce cardiovascular risk is limited for patients with type 1 diabetes and has not yet been established for those with type 2 diabetes. Nonetheless, treating hyperglycaemia may reduce the incidence of lipid abnormalities, vascular abnormalities and hypertension. This new understanding of the pathophysiology of cardiovascular disease in patients with diabetes may help in addressing the underlying processes at an earlier stage of disease.