Cognitive impairment in patients with type 2 diabetes mellitus: prevalence, pathogenetic mechanisms, the effect of antidiabetic drugs

In recent years, a large amount of data has been accumulated on the relationship between cognitive impairment, dementia and diabetes mellitus. This article presents an overview of modern literature, including the definition of cognitive functions, the modern classification of cognitive impairment, pathogenetic mechanisms of diabetes mellitus influence on the development of cognitive impairment and dementia (neurogenesis, integrity of the blood-brain barrier, systemic inflammatory reactions, hyper- and hypoglycemia, insulin resistance, vascular dysfunction of the microvasculature and increase in glucocorticosteroids). The influence of anti-diabetic medications on cognitive functions has been examined in detail: insulin preparations, oral hypoglycemic agents of the biguanide group (metformin), thiazolidinediones (rosiglitazone and pioglitazone), sulfonylurea derivatives (glycazide, glipizide), a-glucosidase (acarbose) inhibitors, incretin-directed therapy (receptor agonists glucan-like peptide (exenatide and liraglutide) and inhibitors of dipeptidylpeptidase type 4 (sitagliptin, vildagliptin and alogliptin)), sodium glucose inhibitors cotransporter type 2. The data demonstrating a multidirectional effect on the cognitive functions of various antidiabetic drugs is presented, the possible influence on the rate of progression of cognitive impairment and the risk of dementia of intensive control of plasma glucose level in comparison with the standard decrease in patients with type 2 diabetes is analyzed.

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