Review Article - Cerebrovascular Disease in Type 2 Diabetes Mellitus

Incidence of CVD in diabetic men was reported to be twice as that of non-diabetics and almost three times greater in diabetic women in the Framingham Study. It is postulated that excessive glycation and oxidation, endothelial dysfunction and increased platelet aggregation may be responsible for endothelial proliferation and thickening of plasmatic membrane in small blood vessels ('lipohyalinosis') leading to lacunar infarction. Prothrombotic state may precipitate a stroke, however, platelet aggregability, elevated fibrinopeptide A (FPA) and D-dimer were not significantly related to stroke in diabetic mellitus (DM), whereas suppressed fibrinolytic activity was a common finding. Of many unknown factors in pathogenesis, the deficient insulin secretion, resistance to action of insulin at level of 'insulin receptors', changes in counter regulatory hormones (e.g. glucagon, pancreatic polypetides, growth hormone, catecholamines, etc.) and decrease in the hepatic sensitivity to insulin action in suppressing glucose output have received more attention. Hyperosmolar state can simulate stroke syndromes. Early recognition and treatment of risk factors such as hypertension or better glycemic control, correction of hyperlipidemia or obesity in diabetic population are important. In diabetic subjects already showing recurrent transient cerebral ischemic attacks (TIAs) or minor strokes, the benefit of antiplatelet agents or antithrombotic therapy in prevention of major strokes is well established. Ramipril has been found to be effective in reducing stroke risk by 33% in diabetic patinets in HOPE study.