The diabetic brain and cognition

Abstract

The prevalence of both Alzheimer's disease (AD) and vascular dementia (VaD) is increasing with the aging of the population. Studies from the last several years have shown that people with diabetes have an increased risk for dementia and cognitive impairment. Therefore, the authors of this consensus review tried to elaborate on the role of diabetes, especially diabetes type 2 (T2DM) in both AD and VaD. Based on the clinical and experimental work of scientists from 18 countries participating in the International Congress on Vascular Disorders and on literature search using PUBMED, it can be concluded that T2DM is a risk factor for both, AD and VaD, based on a pathology of glucose utilization. This pathology is the consequence of a disturbance of insulin-related mechanisms leading to brain insulin resistance. Although the underlying pathological mechanisms for AD and VaD are different in many aspects, the contribution of T2DM and insulin resistant brain state (IRBS) to cerebrovascular disturbances in both disorders

Clock Drawing Test: A Simple Scoring System for the Accurate Screening of Cognitive Impairment in Patients with Mild Cognitive Impairment and Dementia

“…They were placed into either the AD or the MCI group according to the recommendations from the National Institute on Aging-Alzheimer's Association workgroups on diagnostic guidelines for AD [10,11]. The first group consisted of patients with MCI due to AD [10]; the second group consisted of patients with AD [11]; and the third group consisted of patients who had two aetiologies: AD and vascular MD (e.g., two or more lacunar infarcts on CT/MRI images or Fazekas score of 3) [12,13]. The control group was composed of healthy volunteers.…”

Association of glycated haemoglobin (HbA1C) level with working memory on type-2 diabetes mellitus and prediabetic patients

“…Even excessive postprandial blood glucose level fluctuations even at the prediabetes stage, even though metabolic control is still relatively good, can lead to vascular complications. 4,11 The existence of a significant difference between the group of type-2 DM and prediabetes for working memory can be caused because there are indeed many factors that influence the decline in cognitive function, especially the memory domain in type 2 diabetes mellitus as mentioned in the Bedi and Dang study which concluded that shortterm and working memory decreased significantly in type 2 DM patients, which may be due to age of onset, duration, vascular dementia, hyperglycemia or hypoglycemia. The study also revealed that short-term memory and working memory were negatively correlated with the duration of diabetes.…”

“…2 Not only that daily fluctuations in blood glucose levels also influence the decline in cognitive function. 4 Zhang et al, revealed a high association between HbA1c and blood glucose levels with a decrease in the volume and microstructure of the hippocampus. Even in individuals without type 2 diabetes mellitus or impaired glucose tolerance, high blood glucose levels chronically have a negative influence on cognitive function.…”

Endothelin and Diabetic Complications: a Brain-Centric View

“…Yet, cognitive impairment remains to be one of the less understood and less studied complications of diabetes. As recently reviewed, there may be differences in the pathogenesis of the diseases between type 1 and type 2 diabetes (Hardigan et al 2016b, Moheet et al 2015, Riederer et al 2017. Readers are referred to these reviews on diabetes and cognitive impairment in general.…”