Cognitive impairment in diabetic patients: Can diabetic control prevent cognitive decline?

Cognitive Impairment and Associated Factors Among Adults with Type 2 Diabetes Mellitus in Bahir Dar City Referral Hospitals, 2021: Cross-Sectional Study

Background

Neurocognitive impairment, characterized by reduced performance in various cognitive domains, has been significantly linked with glycemic control in type 2 diabetes mellitus (T2DM) patients. Poorly controlled diabetes often results in decreased cognitive abilities, and a longer duration of the disease is associated with lower cognitive levels.

Objective

This study aimed to evaluate the prevalence of cognitive impairment in adults with T2DM and identify related factors.

Methods

An institution-based cross-sectional study was conducted among 421 adults with T2DM. A systematic random sampling was used to select study participants in two referral hospitals in Bahir Dar, Ethiopia. Standardized Mini-Mental State Examination tool was used. Binary logistic regression was used. Significance was declared at p value≤0.05 with 95% confidence interval.

Results

Over a quarter (27.6%) of participants were identified as cognitively impaired. Factors associated with lower cognitive status included older age, being single, lower education level, farming occupation, presence of comorbidity, and engagement in moderate physical activity.

Conclusions

In conclusion, the prevalence of cognitive impairment among T2DM patients is a growing concern. Several risk factors have been identified like age group, marital status, education level, occupation, presence of comorbidity, and moderate physical activities. The impact of cognitive impairment on the quality of life and functional abilities of T2DM patients should not be underestimated.

Prevalence of Cognitive Impairment and Associated Factors Among Diabetes Mellitus Patients Attending Follow-up Treatment at Fiche General Hospital, North Ethiopia

Introduction

Cognitive impairment is having trouble remembering, learning new things, concentrating, or making decisions that affect the daily life of diabetic patients. The worldwide prevalence of diabetes mellitus (DM) was 2.8% in 2000 and is estimated to be 4.4% by 2030.

Objective

To assess the prevalence of cognitive impairment and associated factors among DM patients attending follow-up treatment at Fiche General Hospital, North Ethiopia, 2022.

Methods

A hospital-based cross-sectional study was conducted from July 15 to September 15, 2022. The total sample size was 421 and a systematic random sampling technique was used. Data were collected through a face-to-face interview. Data were entered using EpiData Version 3.1 and exported to SPSS Version 24 for analysis. Statistically significant was declared at a P-value of less than .05 with an adjusted odds ratio (AOR) and 95% confidence interval (CI).

Result

The prevalence of cognitive impairment in the current study was 56.3% with (95% CI: 51.5-60.8). Primary educational status (AOR 6.73, 95% CI: 2.92-15.51), having Type II DM (AOR 4.93, 95% CI: 2.84-8.56), uncontrolled blood sugar (AOR 6.24, 95% CI: 3.84-10.17), and current alcohol use (AOR 1.94, 95% CI: 1.11-3.36) were significantly associated.

Conclusion

About three in 5 DM patients attending follow-up treatment at Fiche General Hospital were suffering from cognitive impairment. Educational status, type of DM, status of fasting blood sugar, and current alcohol use were associated with cognitive impairment among DM patients. Therefore, improving educational status, controlling blood sugar, and avoiding alcohol use may reduce the risk of cognitive impairment in DM patients.

Diabetic neuropathy: A NRF2 disease?

The transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) has multifarious action with its target genes having redox-regulating functions and being involved in inflammation control, proteostasis, autophagy, and metabolic pathways. Therefore, the genes controlled by NRF2 are involved in the pathogenesis of myriad diseases, such as cardiovascular diseases, metabolic syndrome, neurodegenerative diseases, autoimmune disorders, and cancer. Amidst this large array of diseases, diabetic neuropathy (DN) occurs in half of patients diagnosed with diabetes and appears as an injury inflicted upon peripheral and autonomic nervous systems. As a complex effector factor, NRF2 has entered the spotlight during the search of new biomarkers and/or new therapy targets in DN. Due to the growing attention for NRF2 as a modulating factor in several diseases, including DN, this paper aims to update the recently discovered regulatory pathways of NRF2 in oxidative stress, inflammation and immunity. It presents the animal models that further facilitated the human studies in regard to NRF2 modulation and the possibilities of using NRF2 as DN biomarker and/or as target therapy.

A. SD. A diagnosis model for brain atrophy using deep learning and MRI of type 2 diabetes mellitus

Objective

Type 2 Diabetes Mellitus (T2DM) is linked to cognitive deterioration and anatomical brain abnormalities like cerebral brain atrophy and cerebral diseases. We aim to develop an automatic deep learning-based brain atrophy diagnosis model to detect, segment, classify, and predict the survival rate.

Methods

Two hundred thirty-five MRI images affected with brain atrophy due to prolonged T2DM were acquired. The dataset was divided into training and testing (80:20%; 188, 47, respectively). Pre-processing is done through a novel convolutional median filter, followed by segmentation of atrophy regions, i.e., the brain shrinkage, white and gray matter is done through the proposed TRAU-Net model (Transfer Residual Attention U-Net), classification with the proposed Multinomial Logistic regression with Attention Swin Transformer (MLAST), and prediction of chronological age is determined through Multivariate CoX Regression model (MCR). The classification of Brain Atrophy (BA) types is determined based on the features extracted from the segmented region. Performance measures like confusion matrix, specificity, sensitivity, accuracy, F1-score, and ROC-AUC curve are used to measure classification model performance, whereas, for the segmentation model, pixel accuracy and dice similarity coefficient are applied.

Results

The pixel accuracy and dice coefficient for segmentation were 98.25 and 96.41, respectively. Brain atrophy multi-class classification achieved overall training accuracy is 0.9632 ± 1.325, 0.9677 ± 1.912, 0.9682 ± 1.715, and 0.9521 ± 1.877 for FA, PA, R-MTA, and L-MTA, respectively. The overall AUC-ROC curve for the classification model is 0.9856. The testing and validation accuracy obtained for the proposed model are 0.9379 and 0.9694, respectively. The prediction model's performance is measured using correlation coefficient (r), coefficient determination r2, and Mean Square Error (MSE) and recorded 0.951, 0.904, and 0.5172, respectively.

Conclusion

The brain atrophy diagnosis model consists of sub-models to detect, segment, and classify the atrophy regions using novel deep learning and multivariate mathematical models. The proposed model has outperformed the existing models regarding multi-classification and segmentation; therefore, the automated diagnosis model can be deployed in healthcare centers to assist physicians.

Dementia in Diabetes: The Role of Hypoglycemia

Hypoglycemia, a common consequence of diabetes treatment, is associated with severe morbidity and mortality and has become a major barrier to intensifying antidiabetic therapy. Severe hypoglycemia, defined as abnormally low blood glucose requiring the assistance of another person, is associated with seizures and comas, but even mild hypoglycemia can cause troubling symptoms such as anxiety, palpitations, and confusion. Dementia generally refers to the loss of memory, language, problem-solving, and other cognitive functions, which can interfere with daily life, and there is growing evidence that diabetes is associated with an increased risk of both vascular and non-vascular dementia. Neuroglycopenia resulting from a hypoglycemic episode in diabetic patients can lead to the degeneration of brain cells, with a resultant cognitive decline, leading to dementia. In light of new evidence, a deeper understating of the relationship between hypoglycemia and dementia can help to inform and guide preventative strategies. In this review, we discuss the epidemiology of dementia among patients with diabetes, and the emerging mechanisms thought to underlie the association between hypoglycemia and dementia. Furthermore, we discuss the risks of various pharmacological therapies, emerging therapies to combat hypoglycemia-induced dementia, as well as risk minimization strategies.

Molecular mechanisms underlying hyperglycemia associated cognitive decline

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia. DM can lead to a number of secondary complications affecting multiple organs in the body including the eyes, kidney, heart, and brain. The most common effect of hyperglycemia on the brain is cognitive decline. It has been estimated that 20-70% of people with DM have cognitive deficits. High blood sugar affects key brain areas involved in learning, memory, and spatial navigation, and the structural complexity of the brain has made it prone to a variety of pathological disorders, including T2DM. Studies have reported that cognitive decline can occur in people with diabetes, which could go undetected for several years. Moreover, studies on brain imaging suggest extensive effects on different brain regions in patients with T2D. It remains unclear whether diabetes-associated cognitive decline is a consequence of hyperglycemia or a complication that co-occurs with T2D. The exact mechanism underlying cognitive impairment in diabetes is complex; however, impaired glucose metabolism and abnormal insulin function are thought to play important roles. In this review, we have tried to summarize the effect of hyperglycemia on the brain structure and functions, along with the potential mechanisms underlying T2DM-associated cognitive decline.

Application of Grey Relational Analysis to Predict Dementia Tendency by Cognitive Function, Sleep Disturbances, and Health Conditions of Diabetic Patients

Background: The number of elderly diabetic patients has been increasing recently, and these patients have a higher morbidity of dementia than those without diabetes. Diabetes is associated with an increased risk for the development of dementia in elderly individuals, which is a serious health problem. Objectives: The primary aim was to examine whether diabetes is a risk factor for dementia among elderly individuals. The secondary aim was to apply grey theory to integrate the results and how they relate to cognitive impairments in elderly diabetic patients and to predict which participants are at high risk of developing dementia. Methods: Two hundred and twenty patients aged 50 years or older who were diagnosed with diabetes mellitus were recruited. Information on demographics, disease characteristics, activities of daily living, Mini Mental State Examination, sleep quality, depressive symptoms, and health-related quality of life was collected via questionnaires. The grey relational analysis approach was applied to evaluate the relationship between the results and health outcomes. Results: A total of 13.6% of participants had cognitive disturbances, of whom 1.4% had severe cognitive dysfunction. However, with regard to sleep disorders, 56.4% had sleep disturbances of varying degrees from light to severe. Further investigation is needed to address this problem. A higher prevalence of sleep disturbances among diabetic patients translates to a higher degree of depressive symptoms and a worse physical and mental health-related quality of life. Furthermore, based on the grey relational analysis, the grey relation coefficient varies from 0.6217~0.7540. Among the subjects, Participant 101 had the highest value, suggesting a need for immediate medical care. In this study, we observed that 20% of the total participants, for whom the grey relation coefficient was 0.6730, needed further and immediate medical care.

Association between Type 2 Diabetes Mellitus and Brain Atrophy: A Meta-Analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) is known to be associated with cognitive decline and brain structural changes. This study systematically reviews and estimates human brain volumetric differences and atrophy associated with T2DM.

METHODS

PubMed, PsycInfo and Cochrane Library were searched for brain imaging studies reporting on brain volume differences between individuals with T2DM and healthy controls. Data were examined using meta-analysis, and association between age, sex, diabetes characteristics and brain volumes were tested using meta-regression.

RESULTS

A total of 14,605 entries were identified; after title, abstract and full-text screening applying inclusion and exclusion criteria, 64 studies were included and 42 studies with compatible data contributed to the meta-analysis (n=31,630; mean age 71.0 years; 44.4% male; 26,942 control; 4,688 diabetes). Individuals with T2DM had significantly smaller total brain volume, total grey matter volume, total white matter volume and hippocampal volume (approximately 1% to 4%); meta-analyses of smaller samples focusing on other brain regions and brain atrophy rate in longitudinal investigations also indicated smaller brain volumes and greater brain atrophy associated with T2DM. Meta-regression suggests that diabetes-related brain volume differences start occurring in early adulthood, decreases with age and increases with diabetes duration.

CONCLUSION

T2DM is associated with smaller total and regional brain volume and greater atrophy over time. These effects are substantial and highlight an urgent need to develop interventions to reduce the risk of T2DM for brain health.

Possibility for Prevention of Type 2 Diabetes Mellitus and Dementia Using Three Kinds of Brown Rice Blends after High-Pressure Treatment

As it has been reported that type 2 diabetes mellitus increases the risk of Alzheimer’s disease, we investigated how to prevent type 2 diabetes and dementia using biofunctional boiled rice. We adopted unpolished super-hard rice (SHBR) for diabetes and wax-free unpolished black rice (WFBBR) for dementia and blended those with ordinary non-polished rice (KBR) (blending ratio 4:4:2), adding 2.5% waxy black rice bran (WBB) and 0.3% rice oil after high-pressure treatment (HPT) (WFBSK) to improve its palatability. This boiled rice is rich in dietary fiber, anthocyanin, free ferulic acid and β-secretase inhibitory activity. A randomized, parallel-group comparison study was conducted for 12 weeks with 24 subjects, using Cognitrax to evaluate their cognitive function primarily. Furthermore, as the secondary purpose, we performed a single-dose test for postprandial blood glucose and insulin secretion at the end of the human intervention test. After 12 weeks, consumers of the WFBSK rice exhibited significant improvement in language memory by cognitive test battery compared with those who consumed the control white rice (p < 0.05). Moreover, subjects who consumed the WFBSK rice had lower insulin secretion levels than those who consumed the control polished rice (p < 0.05).

Liraglutide ameliorates diabetes-associated cognitive dysfunction via rescuing autophagic flux

The incidence of diabetes-associated cognitive dysfunction is increasing. However, few clinical interventions are available to prevent the disorder. Several researches have shown that liraglutide, as a glucagon-like peptide-1 analog, has protective effects on various neurodegenerative diseases, but its roles in diabetic cognitive dysfunction are rarely reported. This study aims to investigate the protective effects of liraglutide on diabetic cognitive dysfunction and its underlying mechanisms. In vivo, the effects of liraglutide treatment were investigated in a mouse model of type 2 diabetes mellitus (T2DM). In vitro, we investigated the effects of liraglutide on the high-glucose-induced rat primary neurons. The results showed that liraglutide reduced the escape latency and increased the time in effective area in the Morris water maze test, improved the damage of hippocampal and synaptic ultrastructure, and decreased the accumulation of amyloid β protein in hippocampus of T2DM mice. Furthermore, liraglutide increased the ratio of microtubule-associated protein light 1 chain Ⅱ/Ⅰ, the expression of Beclin1 protein and Lysosome-associated membrane protein 2 in vivo and vitro. Additionally, Bafilomycin A1 which can inhibit the fusion of autophagosome and lysosome partially abolished the effects of liraglutide. These findings indicate liraglutide ameliorates diabetes-associated cognitive dysfunction by rescuing autophagic flux.

Sustained Attention Deficits in Adults With Juvenile-Onset Type 1 Diabetes Mellitus

OBJECTIVE

This study aimed to investigate whether patients with juvenile-onset type 1 diabetes mellitus (T1DM) have poorer sustained attention than their counterparts with adult-onset T1DM, and whether there is a relationship between diabetes-related variables and sustained attention.

METHODS

This study included 76 participants with juvenile-onset T1DM, 68 participants with adult-onset T1DM, and 85 healthy controls (HCs). All participants completed the Sustained Attention to Response Task, Beck Depression Inventory-II, and the Chinese version of the Wechsler Adult Intelligence Scale.

RESULTS

The juvenile-onset group showed more omission errors (p = .007) than the adult-onset group and shorter reaction time (p = .005) than HCs, whereas the adult-onset group showed no significant differences compared with HCs. Hierarchical linear regression analysis revealed that the age of onset was associated with omission errors in T1DM participants (β = -0.275, t = -2.002, p = .047). In the juvenile-onset group, the omission error rate were associated with the history of severe hypoglycemia (β = 0.225, t = 1.996, p = .050), whereas reaction time was associated with the age of onset (β = -0.251, t = -2.271, p = .026). Fasting blood glucose levels were significantly associated with reaction time in both the juvenile-onset and adult-onset groups (β = -0.236, t = -2.117, p = .038, and β = 0.259, t = 2.041, p = .046, respectively).

CONCLUSIONS

Adults with juvenile-onset T1DM have sustained attention deficits in contrast to their adult-onset counterparts, suggesting that the disease adversely affects the developing brain. Both the history of severe hypoglycemia and fasting blood glucose levels are factors associated with sustained attention impairment. Early diagnosis and treatment in juvenile patients are required to prevent the detrimental effects of diabetes.

Spot Urine Albumin Creatinine Ratio can be a Predictor of Cognitive Function in Type 2 Diabetes Mellitus

Introduction

In diabetes mellitus (DM), the underlying pathophysiology of albuminuria and cognitive dysfunction is similar. So, we hypothesized that urinary albumin excretion (UAE) could be linked to cognitive dysfunction in type 2 diabetes mellitus.

Methods and Materials

It was a hospital-based observational study. Patient aged 40-60 years with type 2 DM were included in this study. Complete assessment with detailed history, physical examination, and necessary biochemical investigations including spot urine albumin creatinine ratio (uACR) was done. Cognitive status was determined in all the individuals with the application of Hindi translated version of the mini-mental status examination (MMSE) questionnaire.

Results

In 80 patients, the mean MMSE score was 25.37 ± 3.34. Cognitive dysfunction (score <26) was present in 45% of individuals. Spot uACR, estimated glomerular filtration rate (eGFR), glycated hemoglobin (HbA1c), presence of retinopathy and dyslipidemia were significantly different between the normal and subnormal scoring groups. On multivariate analysis spot uACR was found to be independently predicting odds of developing cognitive dysfunction (OR 1.01, CI 1.004-1.022; P = 0.001). The mean MMSE scores in normo-albuminuric (n = 15), moderately increased albuminuric (n = 48) and severely albuminuric (n = 17) patients were 28.00 ± 1.60, 25.54 ± 3.33 and 22.58 ± 2.31, respectively, which were significantly different among the three groups (P < 0.001).

Conclusions

Spot uACR could be helpful in predicting cognitive decline in people with type 2 DM.

Cardiometabolic Modification of Amyloid Beta in Alzheimer's Disease Pathology

In recent years, several studies have suggested that cardiometabolic disorders, such as diabetes, obesity, hypertension, and dyslipidemia, share strong connections with the onset of neurodegenerative disorders such as Parkinson’s and Alzheimer’s disease (AD). However, establishing a definitive link between medical disorders with coincident pathophysiologies is difficult due to etiological heterogeneity and underlying comorbidities. For this reason, amyloid β (Aβ), a physiological peptide derived from the sequential proteolysis of amyloid precursor protein (APP), serves as a crucial link that bridges the gap between cardiometabolic and neurodegenerative disorders. Aβ normally regulates neuronal synaptic function and repair; however, the intracellular accumulation of Aβ within the brain has been observed to play a critical role in AD pathology. A portion of Aβ is believed to originate from the brain itself and can readily cross the blood-brain barrier, while the rest resides in peripheral tissues that express APP required for Aβ generation such as the liver, pancreas, kidney, spleen, skin, and lungs. Consequently, numerous organs contribute to the body pool of total circulating Aβ, which can accumulate in the brain and facilitate neurodegeneration. Although the accumulation of Aβ corresponds with the onset of neurodegenerative disorders, the direct function of periphery born Aβ in AD pathophysiology is currently unknown. This review will highlight the contributions of individual cardiometabolic diseases including cardiovascular disease (CVD), type 2 diabetes (T2D), obesity, and non-alcoholic fatty liver disease (NAFLD) in elevating concentrations of circulating Aβ within the brain, as well as discuss the comorbid association of Aβ with AD pathology.

Relationship between peripheral neuropathy and cognitive performance in the elderly population

ABSTRACT

There are only a few studies that have shown an association of peripheral neuropathy with cognitive impairment in elderly individuals. Therefore, we investigated the relationship between cognitive performance and peripheral neuropathy.From the database of the National Health and Nutrition Examination Survey (NHANES, 1999-2002), each participant completed a household interview, physical performance test, questionnaire regarding personal health, and Digit Symbol Substitution Test (DSST) to evaluate cognitive performance. The severity of peripheral neuropathy was assessed based on the number of insensate areas in both feet during monofilament examination. We used the multivariate linear regression to analyze the association of the DSST findings with insensate areas of the worse foot.There were 828 participants in our study from NHANES 1999 to 2002; their mean age was 69.96 ± 7.38 years, and 51.3% were male. The β coefficients of the number of insensate areas associated with the DSST findings were all negative values, and the absolute value increased as the number of insensate areas increased. After adjustment for pertinent variables, the correlations remained significantly negative (all P for trend <.001). In addition, subgroup analysis showed no gender differences in the negative association, but this association was not significant in obese participants (P > .05).Our study provides evidence that the severity of peripheral neuropathy is significantly negatively correlated with cognitive performance.

Insulin Resistance as a Common Link Between Current Alzheimer's Disease Hypotheses

Almost 115 years ago, Alois Alzheimer described Alzheimer's disease (AD) for the first time. Since then, many hypotheses have been proposed. However, AD remains a severe health public problem. The current medical approaches for AD are limited to symptomatic interventions and the complexity of this disease has led to a failure rate of approximately 99.6%in AD clinical trials. In fact, no new drug has been approved for AD treatment since 2003. These failures indicate that we are failing in mimicking this disease in experimental models. Although most studies have focused on the amyloid cascade hypothesis of AD, the literature has made clear that AD is rather a multifactorial disorder. Therefore, the persistence in a single theory has resulted in lost opportunities. In this review, we aim to present the striking points of the long scientific path followed since the description of the first AD case and the main AD hypotheses discussed over the last decades. We also propose insulin resistance as a common link between many other hypotheses.

Relationship of Established Cardiovascular Risk Factors and Peripheral Biomarkers on Cognitive Function in Adults at Risk of Cognitive Deterioration

BACKGROUND

There is a paucity of information on the role of microvascular and inflammatory biomarkers in cognitive dysfunction.

OBJECTIVE

This study sought to evaluate the relationships between established and a number of peripheral biomarkers on cognitive patterns in 108 older adults with memory complaints.

METHODS

Participants in the AIBL Active study aged 60 years and older with at least one vascular risk factor and memory complaints completed a neuropsychological test battery and provided cross-sectional health data. Linear regression models adjusted for covariates examined associations between cognitive performance and a panel of vascular risk factors (Framingham cardiovascular scores, hs-CRP, homocysteine, fasting glucose, LDL-cholesterol) and peripheral biomarkers (TNF-α, BDNF, VCAM-1, ICAM-1, PAI-1, CD40L).

RESULTS

Higher fasting glucose and homocysteine levels were independent factors associated with poorer performance in Trail Making Test (TMT) B (adjusted β= 0.40±0.10 and 0.43±0.09, respectively). Increasing homocysteine levels were weakly associated with poorer global cognition and delayed recall (adjusted β= 0.23±0.10 and -0.20±0.10 respectively). Increasing Framingham cardiovascular scores were related to poorer performance in TMT B (β  = 0.42±0.19). There was early evidence of associations between increasing plasma TNF-α and poorer TMT B (adjusted β  = 0.21±0.10) and between increasing BDNF and better global cognition (β= -0.20±0.09).

CONCLUSION

This study provides evidence to support the associations between vascular risk factors (Framingham scores, fasting glucose, and homocysteine) and poorer cognitive functions. Additionally, we measured several peripheral biomarkers to further investigate their associations with cognition. The relationship between TNF-α, BDNF, and cognitive performance in various domains may offer new insights into potential mechanisms in vascular cognitive impairment.

Association of Vitamin D Level and Nerve Conduction Study Parameters with Cognitive Function in Diabetic Neuropathy Patients

BACKGROUND: Type 2 diabetes mellitus (T2DM) and its major long-term complication, diabetic polyneuropathy (DPN), continue to be a major global health problem and are important contributors of significant disability worldwide. Vitamin D plays a significant role in their pathogenesis as well as in the development of dementia in non-diabetic patients. Nevertheless, the role of Vitamin D in the development of cognitive impairment in DPN patients has not yet been extensively studied. AIM: We aimed to investigate the association between Vitamin D level and cognitive function in DPN patients and to evaluate several potential contributor factors to cognition, including demographic factors, glycemic control, and nerve conduction study (NCS) parameters. METHODS: Thirty-one DPN patients were included in this cross-sectional study. Patients were recruited from the outpatient endocrinology and neurology clinic of Haji Adam Malik General Hospital Medan Indonesia. We used the diabetic neuropathy examination (DNE) scale, diabetic neuropathy symptom (DNS) scale, and NCS to determine the presence and severity of the neuropathy. We measured the levels of Vitamin D, random blood sugar, and glycated hemoglobin (HbA1c). Cognitive function was assessed using the Indonesian version of Montreal Cognitive Assessment (MoCA-INA), trail making test A and B (TMT A and TMT B), and verbal fluency test. RESULTS: Most of the patients were female (80.6%), with a mean age of 55.71 ± 8.34 years. The proportion of patients with abnormal cognitive function was higher than cognitively unimpaired patients. The mean of MoCA-INA score and level of Vitamin D was lower than normal, 23.32 ± 3.00 and 24.91 ± 13.59 ng/ml, respectively. Using the Pearson correlation test, we did not find any significant association of Vitamin D level, NCS parameters, and other clinical characteristics with global cognitive function. Age and level of education were significantly associated with MoCA-INA score. Blood sugar level was significantly higher in patients with normal TMT-A and TMT-B tests compared to patients with abnormal results. CONCLUSION: Vitamin D and NCS parameters are not associated with cognitive function. Of the demographic and clinical characteristics, a significant association exists between age, level of education, and blood sugar level and cognition. This might suggest the complexity underlying cognitive impairment in T2DM patients.

Predictors of Subjective Cognitive Decline Among People With Diabetes: Data From the Behavioral Risk Factor Surveillance System

PURPOSE

The purpose of this study was to examine the prevalence of subjective cognitive decline (SCD) and SCD-related functional limitations among people with diabetes and to identify socioeconomic and comorbidity risk factors associated with SCD.

METHODS

This study analyzed data from the 2017 Behavioral Risk Factor Surveillance System (BRFSS) with background variables (race, gender, education, and age), health-related factors (self-rated health, BMI, insurance, and comorbid conditions), and health behaviors (smoking, exercise, alcohol consumption) entered simultaneously to estimate logistic regression models of SCD.

RESULTS

Within the sample (n = 5263 adults with diabetes), 48% were age ≥65 years; 50% were male; 55% were non-Hispanic White; and of the 15% who reported having SCD, 57% had functional limitations. Increased odds of reporting SCD were observed among individuals who were Hispanic (odds ratio [OR] = 2.21, P < .001), male (OR = 1.47, P < .01), depressed (OR = 3.85, P < .001), or had arthritis (OR = 1.43, P < .03). Participants with better self-rated health had a reduced likelihood of SCD (OR = 0.51, P < .001).

CONCLUSIONS

Health care providers should assess high-risk patients for self-rated cognitive dysfunction and offer early interventions.

Barriers to Diabetes Self-Management in a Subset of New Zealand Adults with Type 2 Diabetes and Poor Glycaemic Control

BACKGROUND

Despite the fact that there is an increasingly effective armoury of medications to treat diabetes, many people continue to have substantially elevated blood glucose levels. The purpose of this study was to explore what the barriers to diabetes management are in a cohort of people with diabetes and poor glycaemic control.

METHODS

Qualitative semistructured interviews were carried out with 10 people with diabetes who had known diabetes and a recent HbA1c of >11.3% (100 mmol/mol) to explore their experiences of barriers to diabetes self-management and glycaemic control.

RESULTS

Barriers to diabetes management were based around two key themes: biopsychosocial factors and knowledge about diabetes. Specifically, financial concerns, social stigma, medication side effects, and cognitive impairment due to hyperglycaemia were commonly reported as barriers to medication use. Other barriers included a lack of knowledge about their own condition, poor relationships with healthcare professionals, and a lack of relevant resources to support diet and weight loss.

CONCLUSION

People with diabetes with poor glycaemic control experience many of the same barriers as those reported elsewhere, but also experience issues specifically related to their severe hyperglycaemia. Management of diabetes could be improved via the increased use of patient education and availability of locally relevant resources.

Neuroprotective Effect of Syringic Acid by Modulation of Oxidative Stress and Mitochondrial Mass in Diabetic Rats

Diabetes is a metabolic complaint associated with oxidative stress and dysfunction of mitochondria. One of the most common complications of diabetes mellitus is neuropathy. This study evaluated the possible neuroprotective effects of syringic acid (SYR), a natural polyphenolic derivative of benzoic acid, on oxidative damage and mitochondria in the brain, spinal cord, and sciatic nerve of streptozotocin-induced diabetic rats. Different groups of rats including normal control, diabetics (induced by streptozotocin), diabetic groups treated with 25, 50, and 100 mg/kg of SYR, and non-diabetic group treated with only 100 mg/kg of SYR were treated for 6 weeks. Learning and memory function, physical coordination, and acetylcholinesterase (AChE) and antioxidant indexes, as well as mRNA expression of mitochondrial biogenesis, were measured in the brain, spinal cord, and sciatic nerves. Diabetic rats treated with 100 mg/kg SYR exhibited significantly improved learning, memory, and movement deficiency (p < 0.05). SYR 100 mg/kg also significantly upregulated the brain mRNA expression of PGC-1α and NRF-1, the key regulators of energy metabolism, oxidative phosphorylation, and mitochondrial biogenesis. In addition, SYR 100 mg/kg and SYR 50 mg/kg increased the mtDNA/nDNA ratio in the brain and the spinal cord of diabetic rats, respectively (p < 0.05). SYR attenuated the lipid peroxidation in all the tissues, but not significant effects were observed on GSH, AChE, catalase, and superoxide dismutase activity. In all the tests, nonsignificant differences were observed between the control and SYR 100 mg/kg groups. Moreover, SYR reduced inflammation and demyelination in sciatic nerves. This is the first study to reveal the regulation of mitochondrial biogenesis and energy metabolism by SYR, beyond its antioxidant role in the diabetic rats' brain and spinal tissues.

Hyperinsulinemia or Insulin Resistance: What Impacts the Progression of Alzheimer's Disease?

Type 2 diabetes mellitus (T2D), which is often accompanied by hyperinsulinemia and insulin resistance, is associated with an increased risk for developing mild cognitive impairment and Alzheimer's disease (AD); however, the underlying mechanisms for this association are still unclear. Recent findings have shown that hyperinsulinemia and insulin resistance can coexist or be independent events. This makes it imperative to determine the contribution of these individual conditions in impacting AD. This literature review highlights the recent developments of hyperinsulinemia and insulin resistance involvement in the progression and pathogenesis of AD.

Diabetes exacerbates brain pathology following a focal blast brain injury: New role of a multimodal drug cerebrolysin and nanomedicine

Blast brain injury (bBI) is a combination of several forces of pressure, rotation, penetration of sharp objects and chemical exposure causing laceration, perforation and tissue losses in the brain. The bBI is quite prevalent in military personnel during combat operations. However, no suitable therapeutic strategies are available so far to minimize bBI pathology. Combat stress induces profound cardiovascular and endocrine dysfunction leading to psychosomatic disorders including diabetes mellitus (DM). This is still unclear whether brain pathology in bBI could exacerbate in DM. In present review influence of DM on pathophysiology of bBI is discussed based on our own investigations. In addition, treatment with cerebrolysin (a multimodal drug comprising neurotrophic factors and active peptide fragments) or H-290/51 (a chain-breaking antioxidant) using nanowired delivery of for superior neuroprotection on brain pathology in bBI in DM is explored. Our observations are the first to show that pathophysiology of bBI is exacerbated in DM and TiO₂-nanowired delivery of cerebrolysin induces profound neuroprotection in bBI in DM, not reported earlier. The clinical significance of our findings with regard to military medicine is discussed.

Advanced glycation end-products disrupt brain microvascular endothelial cell barrier: The role of mitochondria and oxidative stress

During diabetes mellitus, advanced glycation end-products (AGEs) are major contributors to the development of alterations in cerebral capillaries, leading to the disruption of the blood-brain barrier (BBB). Consequently, this is often associated with an amplified oxidative stress response in microvascular endothelial cells. As a model to mimic brain microvasculature, the bEnd.3 endothelial cell line was used to investigate cell barrier function. Cells were exposed to native bovine serum albumin (BSA) or modified BSA (BSA-AGEs). In the presence or absence of the antioxidant compound, N-acetyl-cysteine, cell permeability was assessed by FITC-dextran exclusion, intracellular free radical formation was monitored with H₂DCF-DA probe, and mitochondrial respiratory and redox parameters were analyzed. We report that, in the absence of alterations in cell viability, BSA-AGEs contribute to an increase in endothelial cell barrier permeability and a marked and prolonged oxidative stress response. Decreased mitochondrial oxygen consumption was associated with these alterations and may contribute to reactive oxygen species production. These results suggest the need for further research to explore therapeutic interventions to restore mitochondrial functionality in microvascular endothelial cells to improve brain homeostasis in pathological complications associated with glycation.

Childhood Hypertension and Effects on Cognitive Functions: Mechanisms and Future Perspectives

Pediatric hypertension is currently one of the most common health concerns in children, given its effects not only on cardiovascular but also cognitive functions. There is accumulating evidence suggesting neurocognitive dysfunction in hypertensive children that could persist even into adulthood. Identifying the precise mechanism(s) underlying the association between childhood hypertension and cognitive dysfunction is crucial as it could potentially lead to the discovery of "druggable" biological targets facilitating the development of treatments. Here, we discuss some of the proposed pathophysiological mechanisms underlying childhood hypertension and cognitive deficits and suggest strategies to address some of the current challenges in the field. The various research studies involving hypertensive adults indicate that long-term hypertension may produce abnormal cerebrovascular reactivity, chronic inflammation, autonomic dysfunction, or hyperinsulinemia and hypercholesterolemia, which could lead to alterations in the brain's structure and functions, resulting in cognitive dysfunction. In light of the current literature, we propose that dysregulation of the hypothalamus-pituitaryadrenal axis, modifications in endothelial brain-derived neurotrophic factor and the gut microbiome may also modulate cognitive functions in hypertensive individuals. Moreover, the above-mentioned pathological states may further intensify the detrimental effects of hypertension on cognitive functions. Thus, treatments that target not only hypertension but also its downstream effects may prove useful in ameliorating hypertension-induced cognitive deficits. Much remains to be clarified about the mechanisms and treatments of hypertension-induced cognitive outcomes in pediatric populations. Addressing the knowledge gaps in this field entails conducting not only clinical research but also rigorous basic and translational studies.

The effects of exercise treatment on learning and memory ability, and cognitive performance in diet-induced prediabetes animals

Changes associated with cognitive function in the high-fat high-carbohydrate diet-induced prediabetes animal model and effect of exercise remain unclear. Rats were randomly assigned to the following groups (n = 6): non-diabetic (ND), prediabetic (PD), intermittent exercising PD (PD + IE) and regular exercising PD (PD + RE). After exercise cessation, oral glucose tolerance (OGT), Novel Object Recognition Test (NORT) and Morris-Water Maze (MWM) tests were performed to assess cognitive function. After sacrifice, malonaldehyde, glutathione peroxidase, interleukin-1β and dopamine concentration in the prefrontal cortex (PFC) and hippocampus were measured. Impaired OGT response in PD animals was accompanied by poor performance on behavioural tasks. This was associated with increased oxidative stress markers and impaired dopamine neurotransmission as evidence by elevated dopamine concentration in the PFC and hippocampal tissue. Improved OGT response by exercise was coupled with improved performance on behavioural tasks, oxidative stress markers and increased interleukin-1β concentration. In regular exercise, this was further coupled with improved dopamine neurotransmission. Cognitive function was affected during prediabetes in animals. This was partly due to oxidative stress and impaired dopamine neurotransmission. Both intermittent and regular exercise improved cognitive function. This was partly mediated by improved glucose tolerance and oxidative stress as well as a subclinical increase in interleukin-1β concentration. In regular exercise, this was further mediated by improved dopamine neurotransmission.

Elevated Fasting Blood Glucose Levels Are Associated With Lower Cognitive Function, With a Threshold in Non-Diabetic Individuals: A Population-Based Study

Background

Cognitive dysfunction has been recognized as a diabetes-related complication. Whether hyperglycemia or elevated fasting glucose are associated with cognitive decline remains controversial. We aimed to investigate the relationship between fasting glucose levels and cognitive function in diabetic and non-diabetic individuals.

Methods

Participants were Japanese diabetic (n = 191) and non-diabetic (n = 616) men, aged 46–81 years, from 2010–2014. Blood samples were taken after a 12 h fast. The Cognitive Ability Screening Instrument (CASI), with a maximum score of 100, was used for cognitive assessment. Cognitive domains of CASI were also investigated. Fractional logit regression with covariate adjustment for potential confounders was used to model cross-sectional relationships between fasting blood glucose and CASI score.

Results

For diabetic individuals, CASI score was 0.38 (95% confidence interval: 0.66–0.12) lower per 1 mmol/L higher fasting glucose level. Short-term memory domain also exhibited an inverse association. For non-diabetic individuals, a reverse U-shaped relationship was observed between fasting glucose and cognitive function, identifying a threshold for highest cognitive performance of 91.8 CASI score at 3.97–6.20 mmol/L (71.5–111.6 mg/dL) fasting glucose. Language ability domain displayed a similar relationship with fasting glucose.

Conclusions

Elevated fasting glucose levels in diabetic men were associated with lower cognitive function, in which short-term memory was the main associated domain. Interestingly, in non-diabetic men, we identified a threshold for the inverse relationship of elevated fasting glucose with cognitive function. Contrastingly to diabetic men, language ability was the main associated cognitive domain among non-diabetic men.

Cognitive impairments in type 2 diabetes, risk factors and preventive strategies

Mild cognitive impairment (MCI) is a modifiable risk factor in progression of several diseases including dementia and type 2 diabetes. If cognitive impairments are not reversed at an early stage of appearance of symptoms, then the prolonged pathogenesis can lead to dementia and Alzheimer's disease (AD). Therefore, it is necessary to detect the risk factors and mechanism of prevention of cognitive dysfunction at an early stage of disease. Poor lifestyle, age, hyperglycemia, hypercholesterolemia, and inflammation are some of the major risk factors that contribute to cognitive and memory impairments in diabetic patients. Mild cognitive impairment was seen in those individuals of type 2 diabetes, who are on an unhealthy diet. Physical inactivity, frequent alcohol consumptions, and use of packed food products that provides an excess of cheap calories are found associated with cognitive impairment and depression in diabetic patients. Omega fatty acids (FAs) and polyphenol-rich foods, especially flavonoids, can reduce the bad effects of an unhealthy lifestyle; therefore, the consumption of omega FAs and flavonoids may be beneficial in maintaining normal cognitive function. These functional foods may improve cognitive functions by targeting many enzymes and molecules in cells chiefly through their anti-inflammatory, antioxidant, or signaling actions. Here, we provide the current concepts on the risk factors of cognitive impairments in type 2 diabetes and the mechanism of prevention, using omega FAs and bioactive compounds obtained from fruits and vegetables. The knowledge derived from such studies may assist physicians in managing the health care of patients with cognitive difficulties.

Neurocognitive impairment in type 2 diabetes mellitus

There is emerging evidence that cognitive impairment could be a diabetes mellitus-related complication. It has been suggested that diabetic people are at increased risk of cognitive decline, since the metabolic and vascular disturbances of the disease affect brain function. Additionally, prolonged exposure to olther potential detrimental factors leads to irreversible cognitive decrements over time due to the aging process. Neurocognitive impairment signifies decreased performance in cognitive domains such as verbal and nonverbal memory, both immediate and delayed memory, executive function, attention, visuospatial and psychomotor performance, information processing speed, semantic knowledge, and language abilities. The aim of the present article is to review the existing literature on the issue of the neurocognitive decline in type 2 diabetes. A literature search of databases was performed, using as keywords "diabetes" and "cognitive impairment," and the reference list of papers so identified were examined, with only English language papers being used. Understanding and preventing diabetes-associated cognitive deficits remains a key priority for future research. It is important to ascertain whether interventions to delay diabetes onset or better control of established disease could prevent some of its adverse effects on cognitive skills.

Personality traits and cognitive function in old-adults with type-2 diabetes

Objectives: Personality may constitute an important domain of influence on cognitive function in old-adults. We assessed the relationship of personality traits and cognitive performance in individuals with Type-2 Diabetes (T2D), and explored possible mediators. Method: The sample includes 377 dementia-free subjects with T2D participating in the Israel Diabetes and Cognitive Decline study who underwent assessment of cognition and personality (mean age 72 ± 4y; 42% females). We assessed the relationships of personality traits with episodic memory, semantic categorization, attention/working memory, executive function and overall cognition using linear regression models adjusting for age, education, sex, BMI, T2D duration, Hemoglobin A1C (HbA1C), hypertension, c-reactive protein, total- to HDL-cholesterol ratio and ApoEɛ4 genotype. A post-hoc mediation analysis was conducted with HbA1C, proportion of days covered (PDC) by T2D prescription claims and depressive symptoms. Results: After adjustment for multiple covariates, high neuroticism levels were associated with poorer performance overall (β= -0.16 ± 0.05; p = 0.001) and with poorer episodic memory, attention/working memory, and semantic categorization (β= -0.14 ± 0.05; p = 0.007, β= -0.12 ± 0.05; p = 0.017 and β= -0.12 ± 0.05; p = 0.018, respectively). High scores on openness to experience were associated with better global cognition (β = 0.11 ± 0.05; p = 0.026), executive functions (β = 0.13 ± 0.05; p = 0.013) and semantic categorization (β = 0.17 ± 0.05; p = 0.001, respectively). Depressive symptoms mediated the association of neuroticism with executive function, and the association of openness with executive function and overall cognition. Conclusion: Personality may play an important role in cognitive health among elderly subjects with T2D. Future studies should address the mechanisms underlying these relationships and specifically the potential role of depressive symptoms which may be in the causal pathway between personality traits and cognitive outcomes.

Different treatment forms of type II diabetes and the risk of dementia in German health claims data

AIMS

The association between type II diabetes (T2D) and increased all-cause dementia risk is well established. However, to date, there is no definite proof that a specific therapy for diabetes can halt a progress of cognitive decline. Therefore, we analyzed a large longitudinal random sample of German health claims data to focus on associations between T2D and dementia and to elucidate the role of different treatment forms of T2D on the risk for dementia.

METHODS

We used a longitudinal random sample (n = 250,000) of claims data of the largest public sickness fund in Germany, the Allgemeine Ortskrankenkasse (AOK). Dementia was defined as ICD-10 codes G31.0, G31.82, G23.1, F00, F01, F02, F03, and F05, and T2D was defined as E11-E14. We performed Cox proportional hazard models to explore the transition into dementia and to calculate the relative risk of dementia dependent on T2D and different T2D treatment forms.

RESULTS

All models were adjusted for sex, age, and each patient's history of depression, renal insufficiency, and cardiovascular comorbidities. Non-pharmacologic-treated diabetics showed a 23% increased dementia risk (p < 0.001) and oral ADM-treated diabetics showed a 16% increased risk (p < 0.001). Insulin-dependent diabetics is still the highest dementia risk (40%; p < 0.001) and obesity additionally attenuated this risk (75%; p < 0.001) increased risk.

CONCLUSIONS

We found that diabetes is an independent risk factor for all-cause dementia. An increased risk for dementia in insulin-dependent and obese subjects with diabetes was evident. Longitudinal studies on the effect of different forms of therapy and weight reduction are needed to verify the results of this study.

Continuity of care for newly diagnosed diabetic patients: A population-based study

This study explores whether continuity of care is associated with health care outcomes and medical care use among patients with newly diagnosed diabetes. A retrospective cohort analysis was performed using the Taiwanese National Health Insurance database, and cases were followed up from January 2010 to December 2012. Four thousand and seven patients with newly diagnosed diabetes were followed for 3 years. The continuity of care was measured using the continuity of care index (COCI) and the usual provider continuity score (UPCS) with high and low dichotomous categories. The probabilities of dementia, hospitalization, emergency room visits, and death were used as health care outcomes. Medical care use was defined as the number of hospital admissions, length of hospital stays, and number of emergency room visits. Adjusted odds ratios (ORs) were obtained using multivariate logistic regression; adjusted ORs for the probabilities of dementia, hospital admissions, and emergency room visits in the higher COCI patient group were 0.582 (p < 0.05), 0.623 (p < 0.001), and 0.650 (p < 0.001), respectively. Negative binomial regression models for medical resource use indicated that the group with higher COCI scores used fewer medical resources compared with the group with lower COCI scores. The findings of UPCS analysis showed that those in the high COCI group also fell into the high UPCS group. In this study, continuity of care was associated with favorable health care outcomes and less medical care uses among newly diagnosed diabetic patients. Long-term relationships between patients and health care providers should be enhanced to provide improved continuity of care.

Cognitive Dysfunction in Persons with Type 2 Diabetes Mellitus: A Concept Analysis

Although cognitive dysfunction is related to type 2 diabetes mellitus (T2DM), the concept has not yet been well defined. The purpose of this study was to define the concept of cognitive dysfunction in persons with T2DM and examine its defining attributes, antecedents, and consequences. Literature was retrieved from 2008 to 2018 by systematically searching the PubMed, CINAHL, and PsycINFO databases. Based on 37 included studies, three defining attributes were identified: cognitive dysfunction is a recognized or unrecognized symptom, is characterized by a subtle decline in one or more cognitive domains, and is accompanied by pronounced structural changes observed in brain imaging. One major antecedent was diabetes-related or diabetes-specific pathological changes. Consequences included interference with diabetes self-management, nonadherence to recommended self-management behaviors, and a higher risk of having hypoglycemic events. The concept analysis provides a theoretical foundation that can be used to guide evaluations and interventions related to cognitive dysfunction in individuals with T2DM.

Local Diffusion Homogeneity Provides Supplementary Information in T2DM-Related WM Microstructural Abnormality Detection

Objectives: We aimed to investigate whether an inter-voxel diffusivity metric (local diffusion homogeneity, LDH), can provide supplementary information to traditional intra-voxel metrics (i.e., fractional anisotropy, FA) in white matter (WM) abnormality detection for type 2 diabetes mellitus (T2DM).

Methods: Diffusion tensor imaging was acquired from 34 T2DM patients and 32 healthy controls. Voxel-based group-difference comparisons based on LDH and FA, as well as the association between the diffusion metrics and T2DM risk factors [i.e., body mass index (BMI) and systolic blood pressure (SBP)], were conducted, with age, gender and education level controlled.

Results: Compared to the controls, T2DM patients had higher LDH in the pons and left temporal pole, as well as lower FA in the left superior corona radiation (p < 0.05, corrected). In T2DM, there were several overlapping WM areas associated with BMI as revealed by both LDH and FA, including right temporal lobe and left inferior parietal lobe; but the unique areas revealed only by using LDH included left inferior temporal lobe, right supramarginal gyrus, left pre- and post-central gyrus (at the semiovale center), and right superior radiation. Overlapping WM areas that associated with SBP were found with both LDH and FA, including right temporal pole, bilateral orbitofrontal area (rectus gyrus), the media cingulum bundle, and the right cerebellum crus I. However, the unique areas revealed only by LDH included right inferior temporal lobe, right inferior occipital lobe, and splenium of corpus callosum.

Conclusion: Inter- and intra-voxel diffusivity metrics may have different sensitivity in the detection of T2DM-related WM abnormality. We suggested that LDH could provide supplementary information and reveal additional underlying brain changes due to diabetes.

Acute glucose fluctuation impacts microglial activity, leading to inflammatory activation or self-degradation

Diabetes mellitus is associated with an increased risk of Alzheimer’s dementia and cognitive decline. The cause of neurodegeneration in chronic diabetic patients remains unclear. Changes in brain microglial activity due to glycemic fluctuations may be an etiological factor. Here, we examined the impact of acute ambient glucose fluctuations on BV-2 microglial activity. Biochemical parameters were assayed and showed that the shift from normal glucose (NG; 5.5 mM) to high glucose (HG; 25 mM) promoted cell growth and induced oxidative/inflammatory stress and microglial activation, as evidenced by increased MTT reduction, elevated pro-inflammatory factor secretion (i.e., TNF-α and oxygen free radicals), and upregulated expression of stress/inflammatory proteins (i.e., HSP70, HO-1, iNOS, and COX-2). Also, LPS-induced inflammation was enlarged by an NG-to-HG shift. In contrast, the HG-to-NG shift trapped microglia in a state of metabolic stress, which led to apoptosis and autophagy, as evidenced by decreased Bcl-2 and increased cleaved caspase-3, TUNEL staining, and LC3B-II expression. These stress episodes were primarily mediated through MAPKs, PI3K/Akt, and NF-κB cascades. Our study demonstrates that acute glucose fluctuation forms the stress that alters microglial activity (e.g., inflammatory activation or self-degradation), representing a novel pathogenic mechanism for the continued deterioration of neurological function in diabetic patients.

Influence of Sex on Cognition and Peripheral Neurovascular Function in Diabetic Mice

Cognition impairment and peripheral neuropathy (DPN) are two major complications of diabetes. The aim of the present study is to investigate the effect of sex differences on cognition and DPN in diabetic mice. Male and female BKS.Cg-m+/+Leprdb/J (db/db) and db/m mice were used. At ages of 20 and 30 weeks, all animals were subjected to learning, memory and neurological function tests. Regional blood flow in footpad and sciatic nerves were measured using laser Doppler flowmetry. Our data showed that male db/db mice aged 20 weeks and 30 weeks spent significantly more time to locate the hidden platform in the correct quadrant and spent significantly less time exploring the cage with a new stranger mouse compared to aged-matched female db/db mice. Electrophysiological recordings showed that male db mice aged 30 weeks had significantly reduced motor and sensory nerve conduction velocity compared with females. Hot plate and tactile allodynia tests revealed that males exhibited significantly higher thermal and mechanical latency than females. Male db mice aged 30 weeks displayed significantly reduced blood perfusion in sciatic nerve and footpad tissues compared with females. In addition, compared with male and female non-diabetic db/m mice, db/db mice exhibited increased time spent on locating the hidden platform, decreased time spent on exploring the novel odor bead and an unfamiliar mouse, as well as showed significantly lower levels of blood flow, lower velocity of MCV and SCV, higher thermal and mechanical latencies. Blood glucose levels and body weight were not significantly different between male and female diabetic animals (age 30 weeks), but male db mice showed a higher serum total cholesterol content. Together, our data suggest that males develop a greater extent of diabetes-induced cognition deficits and peripheral neurovascular dysfunction than females.

Higher fasting plasma glucose is associated with smaller striatal volume and poorer fine motor skills in a longitudinal cohort

Previous studies have demonstrated associations between higher blood glucose and brain atrophy and functional deficits, however, little is known about the association between blood glucose, striatal volume and striatal function despite sensori-motor deficits being reported in diabetes. This study investigated the relationship between blood glucose levels, striatal volume and fine motor skills in a longitudinal cohort of cognitively healthy individuals living in the community with normal or impaired fasting glucose or type 2 diabetes. Participants were 271 cognitively healthy individuals (mean age 63 years at inclusion) with normal fasting glucose levels (<5.6 mmol/L) (n=173), impaired fasting glucose (5.6-6.9 mmol/L) (n=57), or with type 2 diabetes (≥7.0 mmol/L) (n=41). Fasting glucose, Purdue Pegboard scores as measurement of fine motor skills, and brain scans were collected at wave 1, 2 and 4, over a total follow-up of twelve years. Striatal volumes were measured using FreeSurfer after controlling for age, sex and intracranial volume. Results showed that type 2 diabetes was associated with smaller right putamen volume and lower Purdue Pegboard scores after controlling for age, sex and intracranial volume. These findings add to the evidence suggesting that higher blood glucose levels, especially type 2 diabetes, may impair brain structure and function.

Effects of the Problem Solving Technique in Type 2 Diabetic Patients with Cognitive Impairment: A Randomized Clinical Trial

BACKGROUND

Diabetes mellitus is a common metabolic disorder, one of the lesser known of whose consequences is cognitive disorder. This study aimed to evaluate the effects of problem-solving technique in type 2 diabetic patients with cognitive impairment.

METHODS

This randomized clinical trial was conducted in the south of Iran between December 2014 and April 2015. 96 type 2 diabetic patients with cognitive impairment were randomly divided into two groups. The patients in the intervention group attended classes on problem-solving skills, while the patients in the control group attended the usual classes in the clinic. The quality of life, self-management profile, metabolic indexes of the patients in both groups were measured before and three months after the experiment. Data were analyzed using SPSS version 16.0. Paired t-test, independent t-test, Wilcoxon, Mann-Whitney and Chi-Square tests were used.

RESULTS

The differences between the groups' levels of HbA1c (P=0.02) and HDL (P=0.02) were significant, but the differences between their FBS, cholesterol, triglycerides and LDL were not significant (P>0.05). The mean difference of the changes in the quality of life (P<0.001) between the intervention and control groups was significant. The differences between the two groups in the area of self-management were as follows: patient's anxiety management (P<0.001), patient's capability in using medicine (P<0.001), healthy eating (P<0.001), weight management (P=0.02), and confidence in one's ability to manage his/her diabetes (P<0.001).

CONCLUSION

Applying problem-solving technique significantly enhanced self-management, quality of life and metabolic indexes in type 2 diabetic patients with cognitive impairment. Trial Registration Number: IRCT2014041517283N1.

Activation of Macrophages and Microglia by Interferon-γ and Lipopolysaccharide Increases Methylglyoxal Production: A New Mechanism in the Development of Vascular Complications and Cognitive Decline in Type 2 Diabetes Mellitus?

Methylglyoxal (MGO), a dicarbonyl compound derived from glucose, is elevated in diabetes mellitus and contributes to vascular complications by crosslinking collagen and increasing arterial stiffness. It is known that MGO contributes to inflammation as it forms advanced glycation end products (AGEs), which activate macrophages via the receptor RAGE. The aim of study was to investigate whether inflammatory activation can increase MGO levels, thereby completing a vicious cycle. In order to validate this, macrophage (RAW264.7, J774A.1) and microglial (N11) cells were stimulated with IFN-γ and LPS (5 + 5 and 10 + 10 IFN-γ U/ml or μg/ml LPS), and extracellular MGO concentration was determined after derivatization with 5,6-Diamino-2,4-dihydroxypyrimidine sulfate by HPLC. MGO levels in activated macrophage cells (RAW264.7) peaked at 48 h, increasing 2.86-fold (3.14±0.4 μM) at 5 U/ml IFN-γ+5 μg/ml LPS, and 4.74-fold (5.46±0.30 μM) at 10 U/ml IFN-γ+10 μg/ml LPS compared to the non-activated controls (1.15±0.02 μM). The other two cell lines, J774A.1 macrophages and N11 microglia, showed a similar response. We suggest that inflammation increases MGO production, possibly exacerbating arterial stiffness, cardiovascular complications, and diabetes-related cognitive decline.

The effects of self-efficacy enhancing program on foot self-care behaviour of older adults with diabetes: A randomised controlled trial in elderly care facility, Peninsular Malaysia

BACKGROUND

Self-care behaviour is essential in preventing diabetes foot problems. This study aimed to evaluate the effectiveness of health education programs based on the self-efficacy theory on foot self-care behaviour for older adults with diabetes.

METHODS

A randomised controlled trial was conducted for 12 weeks among older adults with diabetes in elderly care facility in Peninsular Malaysia. Six elderly care facility were randomly allocated by an independent person into two groups (intervention and control). The intervention group (three elderly care facility) received a health education program on foot self-care behaviour while the control group (three elderly care facility) received standard care. Participants were assessed at baseline, and at week-4 and week-12 follow-ups. The primary outcome was foot-self-care behaviour. Foot care self-efficacy (efficacy expectation), foot care outcome expectation, knowledge of foot care and quality of life were the secondary outcomes. Data were analysed with Mixed Design Analysis of Variance using the Statistical Package for the Social Sciences version 22.0.

RESULTS

184 respondents were recruited but only 76 met the selection criteria and were included in the analysis. Foot self-care behaviour, foot care self-efficacy (efficacy expectation), foot care outcome expectation and knowledge of foot care improved in the intervention group compared to the control group (p < 0.05). However, some of these improvements did not significantly differ compared to the control group for QoL physical symptoms and QoL psychosocial functioning (p > 0.05).

CONCLUSION

The self-efficacy enhancing program improved foot self-care behaviour with respect to the delivered program. It is expected that in the future, the self-efficacy theory can be incorporated into diabetes education to enhance foot self-care behaviour for elderly with diabetes living in other institutional care facilities.

TRIAL REGISTRATION

Australian New Zealand Clinical Trial Registry ACTRN12616000210471.

Impact of the Presence of Select Cardiovascular Risk Factors on Cognitive Changes among Dementia Subtypes

BACKGROUND

Studies have shown select associations between cardiovascular risk factors and dementia, but mostly focused on Alzheimer's Disease (AD).

OBJECTIVE

We enhance these works by evaluating the relationship between the presence of cardiovascular risk factors and the rate of cognitive decline, measured using the Mini-Mental State Examination (MMSE) and Clinical Dementia Rating Sum of Boxes (CDR-SUM) on four common dementia subtypes (AD, dementia with Lewy bodies (DLB), frontotemporal dementia (FTD), and vascular dementia (VaD), as well as non-demented elderly individuals (normal)).

METHOD

We used generalized linear mixed models with random intercepts to account for correlation at the patient and center levels for each dementia subtype adjusting for time since initial visit, baseline cognitive score, age, and demographic factors. The cardiovascular risk factors evaluated included body mass index, diabetes, years of smoking, atrial fibrillation, hypertension, and hypercholesterolemia.

RESULTS

Patients diagnosed with AD (n=1899), DLB (n=65), FTD (n=168), or VaD (n=13); or lacked cognitive impairment (normal) (n=3583) were evaluated using data from the National Alzheimer's Coordinating Centers. Cardiovascular risk factors were associated with select dementia subtypes including AD and FTD. Using MMSE and CDR-SUM, recent or active hypertension and hypercholesterolemia were associated with a slower cognitive decline for AD patients, while higher body mass index and years of smoking were associated with a slower cognitive decline for FTD patients. However, several cardiovascular factors demonstrated associations with more rapid cognitive decline.

CONCLUSION

These results demonstrate disease specific associations and can provide clinicians guidance on predicted cognitive changes at the group level using information about cardiovascular risk factors.

Relationship between Insulin Levels and Nonpsychotic Dementia: A Systematic Review and Meta-Analysis

Objectives

To explore the relationship between insulin levels and nonpsychotic dementia.

Methods

Six electronic databases (PubMed, Cochrane, SCI, CNKI, VIP, and Wanfang) were searched from January 1, 2007, to March 1, 2017. Experimental or observational studies that enrolled people with nonpsychotic dementia or abnormal insulin levels in which insulin levels or MMSE scores (events in nonpsychotic dementia) were the outcome measures. Random-effects models were chosen for this meta-analysis. Sample size, mean, s.d., and events were primarily used to generate effect sizes (with the PRIMA registration number CRD42017069860).

Results

50 articles met the final inclusion criteria. Insulin levels in cerebrospinal fluid were lower (Hedges' g = 1.196, 95% CI = 0.238 to 2.514, and P = 0.014), while the levels in peripheral blood were higher in nonpsychotic dementia patients (Hedges' g = 0.853 and 95% CI = 0.579 to 1.127), and MMSE scores were significantly lower in the high insulin group than in the healthy control group (Hedges' g = 0.334, 95% CI = 0.249 to 0.419, and P = 0.000).

Conclusions

Our comprehensive results indicate that blood insulin levels may increase in patients with nonpsychotic dementia.

Blood-Brain Barrier Dysfunction Precedes Cognitive Decline and Neurodegeneration in Diabetic Insulin Resistant Mouse Model: An Implication for Causal Link

Diabetic insulin resistance and pro-diabetic diet are reported to increase dementia risk through unknown mechanisms. Emerging evidence suggests that the integrity of blood-brain barrier (BBB) is central to the onset and progression of neurodegeneration and cognitive impairment. Therefore, the current study investigated the effect of pro-diabetic diets on cognitive dysfunction in association to BBB integrity and its putative mechanisms. In C57BL/6J mice chronically ingested with a diet enriched in fat and fructose (HFF), Morris Water Maze (MWM) test indicated no significant cognitive decline after 4 weeks of HFF feeding compared to low-fat (LF) fed control. However, at this stage, BBB dysfunction accompanied by heightened neuroinflammation in cortex and hippocampal regions was already evident. After 24 weeks, HFF fed mice showed significantly deteriorated cognitive function concomitant with substantial neurodegeneration, which both showed significant associations with increased BBB permeability. In addition, the data indicated that the loss of BBB tight junctions was significantly associated with heightened inflammation and leukocyte infiltration. The data collectively suggest that in mice maintained on pro-diabetic diet, the dysfunctional BBB associated to inflammation and leukocyte recruitment precedes the neurodegeneration and cognitive decline, possibly indicating causal association.

Does social support affect development of cognitive dysfunction in individuals with diabetes mellitus?

[No Abstract Available].

Leucine-rich α2-glycoprotein overexpression in the brain contributes to memory impairment

We previously reported increase in leucine-rich α2-glycoprotein (LRG) concentration in cerebrospinal fluid is associated with cognitive decline in humans. To investigate relationship between LRG expression in the brain and memory impairment, we analyzed transgenic mice overexpressing LRG in the brain (LRG-Tg) focusing on hippocampus. Immunostaining and Western blotting revealed age-related increase in LRG expression in hippocampal neurons in 8-, 24-, and 48-week-old controls and LRG-Tg. Y-maze and Morris water maze tests indicated retained spatial memory in 8- and 24-week-old LRG-Tg, while deteriorated in 48-week-old LRG-Tg compared with age-matched controls. Field excitatory postsynaptic potentials declined with age in LRG-Tg compared with controls at 8, 24, and 48 weeks. Paired-pulse ratio decreased with age in LRG-Tg, while increased in controls. As a result, long-term potentiation was retained in 8- and 24-week-old LRG-Tg, whereas diminished in 48-week-old LRG-Tg compared with age-matched controls. Electron microscopy observations revealed fewer synaptic vesicles and junctions in LRG-Tg compared with age-matched controls, which became significant with age. Hippocampal LRG overexpression contributes to synaptic dysfunction, which leads to memory impairment with advance of age.

Effect of re-coaching on self-injection of insulin in older diabetic patients - Impact of cognitive impairment

AIMS

We investigated the effect of re-coaching on self-injection of insulin and impact of cognitive function in 100 older diabetic patients.

METHODS

We examined patients on a variety of skills and knowledge regarding self-injection of insulin and evaluated the effect of re-coaching the patients after 3months and 4years. We also investigated the influence of cognitive impairment (CI) on coaching.

RESULTS

Skills scores for self-injection of insulin and HbA1c improved significantly 3months after re-coaching. In 51 patients followed-up for 4years, skills scores were maintained during the 4years, while knowledge scores improved after 3months but then returned to the baseline level. In the group of patients with CI as determined by the Mini-Mental Status Examination, skills scores were similar to those in the group without CI, while knowledge scores were significantly lower as compared with those in the group without CI at any time point. Skills scores were maintained during the 4years regardless of CI.

CONCLUSION

The present study showed that re-coaching in skills for self-injection of insulin was effective in improving and maintaining insulin treatment in older diabetic patients, even if patients had CI.