Diabetes mellitus and stroke

Abstract

Epidemiological evidence indicates that type 2 diabetes is an independent risk factor for brain infarction. The rate of brain infarction is a two- to three-fold higher in individuals with diabetes than in those without. Diabetes mellitus is associated with all types of infarctions, including lacunar infarction, atherothrombotic brain infarction and cardioembolic brain infarction. Patients with diabetes mellitus tend to experience small- to mid-sized infarcts in the brainstem or vertebrobasilar territories. The role of glycemic control in reducing macrovascular risk has not been established clearly in patients with type 2 diabetes. In the UKPDS trial, treatment with metformin resulted in significant risk reduction with respect to stroke events. A recent meta-analysis of eight phase 3 studies also suggested that linagliptin may have benefits for stroke prevention in patients with type 2 diabetes. In addition, a subanalysis of the PROactive trial, which evaluated patients with a previous history of stroke, showed a significant decrease in the incidence of strokes in the pioglitazone group with a stroke history. However, most randomized clinical trials have not demonstrated beneficial effects of intensive glycemic therapy on macrovascular (particularly stroke) outcomes in type 2 diabetes patients. Beneficial effects have been shown for multifactorial therapy, including controlling dyslipidemia and/or hypertension in addition to the blood glucose level. The Steno-2 and J-EDIT studies reported a reduction in stroke risk among type 2 diabetic patients following multifactorial therapeutic intervention. These findings indicate that the most effective approach for preventing macrovascular complications, including stroke, is multifactorial risk factor reduction (glycemic control, smoking cessation, aggressive blood pressure control, treatment of dyslipidemia and, for secondary prevention, the daily administration of anti-thrombotic agents).