[Diabetes and the central nervous system].

Diabetes increases the risk of stroke by a factor of 2-4. For primary and secondary stroke prevention, strict glycemic control alone was not superior to standard treatment. However, the risk of stroke in patients with diabetes could be reduced by multimodal risk interventions during the last 20 years by about 50%. Increased glucose levels (poststroke hyperglycemia (PSH)) which indicate a worse prognosis develop in 50% of stroke patients. The potentially beneficial effect of strict glycemic control in PSH by i. v. insulin was neutralized by negative effects of an increased rate of hypoglycemic episodes. Diabetes leads to an increased risk of vascular dementia, but also of the neurodegenerative Alzheimer 's type. Recurrent hypoglycemic episodes affect the timely perception of hypoglycemia by cerebral-mediated mechanisms, which reduces the possibility of counterreactions.