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

Hypoglycemia and the risk of cognitive impairment and dementia in elderly and senile patients with type 2 diabetes

Research results show that poor glycemic control and recurrent episodes of severe hypoglycaemia are associated with a decrease in cognitive function in elderly people with type 2 diabetes mellitus (T2DM). On the other hand, patients with diabetes mellitus associated with cognitive impairment/dementia are most at risk of developing hypoglycaemic conditions. It is obvious that the relationship between hypoglycaemia and dementia is very complex and has a mutually aggravating nature. Studies also show that individuals of older age groups with diabetes and cognitive impairment have a high risk of developing hypoglycaemic conditions, such as unwanted side effects from glucose-lowering therapy. In this case, of particular interest is the question that is being actively studied at the present time, which is concerning the effect of different groups of glucose-lowering antidiabetic drugs on the cognitive status and the rate of cognitive decline in diabetic patients with cognitive impairment. In this review, we attempted to summarise, systematise, and present data available in the literature concerning the effect of hypoglycaemia on the risk of cognitive impairment and dementia in elderly and senile patients with type-2 diabetes, as well as the degree of participation in this process of of various groups of sugar-lowering antidiabetic drugs

The new 2018 European guidelines for the management of arterial hypertension: the most important aspects of use in real-life clinical practice

Aim. To present the fundamental standpoints of renewed 2018 European guidelines for the management of arterial hypertension and to discuss aspects of its use in real-life clinical practice with due consideration of Russian experts opinions. Materials and methods. 2018 European guidelines for the management of arterial hypertension and Russian Society of Cardiology Memorandum on these guidelines are discussed. Results and conclusion. Fundamental standpoints of 2018 European guidelines for the management of arterial hypertension as well as essential and important in context of real-life clinical practice changes in comparison with the previous revision are presented. Much attention is given to risk factors and associated with hypertension organ damage detection. Special focus is made on the main principle of blood pressure pharmacological control – “one pill strategy”. A step to step regimen for prescription of combined antihypertensive therapy where renin angiotensin aldosterone system (RAAS) inhibitors are first line medications is presented. At the first stage the choice combination includes angiotensin-converting-enzyme inhibitor or angiotensin II receptor blocker and dihydropyridine calcium channel blocker or diuretic. It is outlined that for the first time in the guidelines the use of 3-component antihypertensive therapy in the form of “one pill” is emphasized and its actual components are specified (RAAS inhibitor, calcium channel blocker and diuretic). Also a small subset of patients in whom it is possible to use antihypertensive medications in monotherapy is described. The management of elderly and very elderly patients and patients with senile asthenia syndrome is described. Target blood pressure levels depending on comorbid disorders existence such as diabetes mellitus, chronic kidney disease, ischemic kidney disease, stroke and/or transient ischemic attack as well as patient age are discussed. All standpoints of European guidelines for the management of arterial hypertension are discussed from the point of view of Russian experts that is presented in Russian Society of Cardiology Memorandum. The second part of the article presents possibilities of one pill strategy use in combined antihypertensive therapy based of valsartan and discusses the importance of patients’ compliance to blood pressure pharmacological control and ways of improving this compliance

Motivation as a factor affecting the efficiency of cognitive processes in elderly patients with hypertension

The main purpose of the present study was to assess the role of motivation in the effective cognitive activity of elderly hypertension (HTN) patients provided with antihypertensive treatment; 25 patients with HTN took part in the study, stage 1-2; their mean age was 67.6±6.1. The psychological examination program embraced a quantitative measurement of intelligence quotient (IQ) with the Wechsler Adult Intelligence Scale, and an investigation into the qualitative features of their cognitive processes, applying a pathopsychological study procedure (Zeigarnik, 1962, 1972) and the principles of psychological syndrome analysis (Vygotsky-Luria-Zeigarnik school). The results showed that within the psychological syndrome structure of cognitive disorders in HTN patients, the leading part is played by two syndrome-generating factors: a neurodynamic factor and a motivational factor. The patients with reduced motivation would achieve poor general test results, if compared with the group of highly motivated participants. A correlation analysis of the data revealed the interconnection between frequency disturbances in motivation and the frequency in occurrence of various signs of cognitive decline, such as low efficiency in memorization and delayed recall, as well as lower IQ test results. The data provide a strong argument to support the hypothesis that motivation is of particular importance as a factor in the generation of cognitive disorders in HTN patients

Combined therapy with proton pump inhibitors and clopidogrel – focus on cardiovascular risk

Aim. To analyze accessible studies on the problem of potential interaction of proton pump inhibitors and clopidogrel and to evaluate the influence of combined therapy with these pharmacologic agents on cardiovascular adverse effects development. Materials and methods. Data from 43 foreign and Russian literature sources including international clinical guidelines, randomized and prospective clinical studies, cohort and retrospective studies, clinical registries, metaanalyses and systematic reviews were analyzed. Results. The issue of proton pump inhibitors and P2Y12 thrombocytes receptors inhibitor clopidogrel interaction is discussed in the context of cardiovascular risk and influence on essential adverse cardiovascular events (including acute coronary syndrome, stent thrombosis, necessity of myocardial revascularization, stroke, myocardial infarction, all-cause and/or cardiovascular mortality, symptomatic or non- symptomatic gastrointestinal hemorrhage) in patients taking dual antiplatelet therapy. Standpoints of current international guidelines concerning possibility and necessity of theses medicines use in combination are presented. Data from a significant amount of studies on proton pump inhibitors influence on clopidogrel clinical effectiveness are discussed. The results of analyzed studies demonstrate increased risk of adverse cardiovascular events in the group of patients with ischemic heart disease who receive concomitant treatment with proton pump inhibitors. In particular, in several metaanalyses it was demonstrated that concurrent administration of acetosalicylic acid, clopidogrel, and proton pump inhibitors reduces frequency of gastrointestinal hemorrhage, but at the same time increases risk of major adverse cardiovascular events, increases probability of stent thrombosis and necessity of revascularization. Nevertheless, these results were not confirmed in multiple randomized clinical studies. Conclusion. Considering available literature data we can make a conclusion of necessity of large well-orchestrated randomized clinical studies conduction in order to find a conclusive answer on safety of proton pump inhibitors use in patients after percutaneous coronary intervention or coronary artery bypass surgery, including patients after acute coronary syndrome

Medically induced hypoglycemia: focus on medications not included in the group of antihyperglycemic medications

Recently, doctors face the problem of patients with hypoglycemia conditions caused by the use of drugs that are not drugs for the treatment of diabetes. This is due to the increase in the number of multimorbid diseases in people of older age groups and, consequently, an increase in the number of drugs used simultaneously (polypharmacy). Hypoglycemia can complicate the course of concomitant diseases, contributes to the occurrence of arrhythmias, increases the risk of cardiovascular events, cognitive impairment, including dementia, increases the frequency and duration of episodes of myocardial ischemia. Risk factors for the development of drug-induced hypoglycemia include: elderly and senile age; reduced glomerular filtration rate, liver failure (reduced gluconeogenesis), reduced food consumption (insufficient glucose consumption); excessive alcohol consumption (reduced gluconeogenesis, insufficient food intake); simultaneous intake of several drugs that can lead to hypoglycemia. The most frequently drug-induced hypoglycemia develops against the background of the use of quinolones, pentamidine, quinine, β-blockers, angiotensin-converting enzyme inhibitors and insulin-like growth factor. The main vehicle to prevent drug-induced hypoglycemia is to stop its use and/or replace it with another drug that does not have this side effect. If it is impossible to completely abandon the drug, it is necessary to minimize the risk of hypoglycemia in the following ways: use long-term administration of the same concentration of the drug (if possible, prolonged forms), reduce the dose of the drug (use the lowest possible effective doses), control the concentration of glucose in the blood

Water Exchange between Deep Basins of the Bransfield Strait

The Bransfield Strait is a relatively deep and narrow channel between the South Shetland Islands and the Antarctic Peninsula contributing to the water transport between the Pacific and Atlantic sectors of the Southern Ocean. The strait can be divided into three deep separate basins, namely, the western, central, and eastern basins. The sources of deep waters in the three basins are different, leading to differences in thermohaline properties and water density between the basins. The difference in water density should in turn cause intense deep currents from one basin to another through narrow passages over the sills separating the basins. However, there are still no works dedicated to such possible overflows in the Bransfield Strait. In this study, we report our new CTD and LADCP measurements performed in 2022 over the watersheds between the basins. Quasisimultaneous observations of the main circulation patterns carried out at several sections allowed us to analyze the evolution of thermohaline and kinematic structures along the Bransfield Strait. Volume transports of waters in the strait were estimated on the basis of direct velocity observations. These new data also indicate the existence of intense and variable deep current between the central and eastern basins of the strait. The analysis of historical data shows that the mean flow is directed from the central to the eastern basin. In addition, LADCP data suggest the intensification of the flow in the narrow part of the sill between the basins, and the possible mixing of deep waters at this location

Water Exchange between Deep Basins of the Bransfield Strait

The Bransfield Strait is a relatively deep and narrow channel between the South Shetland Islands and the Antarctic Peninsula contributing to the water transport between the Pacific and Atlantic sectors of the Southern Ocean. The strait can be divided into three deep separate basins, namely, the western, central, and eastern basins. The sources of deep waters in the three basins are different, leading to differences in thermohaline properties and water density between the basins. The difference in water density should in turn cause intense deep currents from one basin to another through narrow passages over the sills separating the basins. However, there are still no works dedicated to such possible overflows in the Bransfield Strait. In this study, we report our new CTD and LADCP measurements performed in 2022 over the watersheds between the basins. Quasisimultaneous observations of the main circulation patterns carried out at several sections allowed us to analyze the evolution of thermohaline and kinematic structures along the Bransfield Strait. Volume transports of waters in the strait were estimated on the basis of direct velocity observations. These new data also indicate the existence of intense and variable deep current between the central and eastern basins of the strait. The analysis of historical data shows that the mean flow is directed from the central to the eastern basin. In addition, LADCP data suggest the intensification of the flow in the narrow part of the sill between the basins, and the possible mixing of deep waters at this location

Physical and Biological Features of the Waters in the Outer Patagonian Shelf and the Malvinas Current

The aim of this study is to trace how the fine-thermohaline and kinematic structure, formed over a section along 45.8° S in the interaction zone of the outer Patagonian Shelf (PS) and Malvinas (Falkland) Current (MC) System waters, affect the spatial distribution of bio-optical characteristics, phyto/zooplankton, birds, and marine mammals. For the first time, simultaneous multidisciplinary observations at high spatial resolution (~2.5 km) were performed in this region during the cruise of the R/V “Akademic Mstislav Keldysh” in February 2022. A fine structure of alternating upwelling and downwelling zones over the PS and slope was identified, which resulted from the interaction between the MC inshore branch (MCi), bottom topography, and wind. This interaction significantly affects all the physical, and optical characteristics analyzed in the work, as well as the biota of the region. It was found that the euphotic zone is larger in the downwelling zones than in the upwelling zones, and all spatially local maxima of phytoplankton photosynthetic efficiency are observed in the zones between upwelling and downwelling. Phytoplankton along the section were represented by 43 species. A total of 30 zooplankton species/taxa were identified. Three species of marine mammals and 11 species of birds were recorded in the study site. Most of the phytoplankton species list were formed by dinoflagellates, and picoplankton Prasinoderma colonial quantitatively dominated everywhere. Two floristic and three assemblage groups were distinguished among the analyzed phytoplankton communities. High phytoplankton biodiversity was observed above the PS and low above the PS edge and in the MCi core. Copepods mostly dominated in zooplankton. Subantarctic species/taxa of zooplankton concentrated in the nearshore waters of the PS, while Antarctic species/taxa were most abundant in the zone between the MCi and the MC offshore branch (MCo). The relative abundance of birds in the PS was several times higher than in the MCo. The minimum abundance of birds was in the MCi in the zone of the strongest upwelling identified above the PS edge