Effect of poor glycemic control in cognitive performance in the elderly with type 2 diabetes mellitus: The Mexican Health and Aging Study

Establishing the feasibility and preliminary efficacy of a health belief model based educational training program on health belief perceptions and dementia-preventive behaviors in people with type 2 diabetes

This quasi-experimental study evaluated feasibility and preliminary efficacy of dementia-preventive educational training intervention program based on the health belief model for improving perceived health beliefs and dementia-preventive behaviors among people with type 2 diabetes mellitus. Two community hospitals with 72 eligible participants were chosen from 12 local institutions using simple random sampling method. One hospital (22 patients) was allocated to dementia-preventive educational training intervention, and the other hospital (23 patients) was allocated to control intervention (using simple random sampling). Primary study outcome was feasibility, and secondary outcomes were changes in dementia prevention behaviors and health belief perceptions. Recruitment rate was 62.5% (45/72) and 22 patients in each group totally completed outcome measures and attended sessions, indicating feasibility of the intervention and study design. There were no significant differences between groups at baseline. After training, participants in the intervention group had significantly higher scores than control group in prevention behaviors and perceptions of health beliefs. The intervention group experienced significant with-group changes in outcomes. Results show that conducting a subsequent fully powered experimental study is feasible, and the intervention has promising efficacy.

Changes in trends and patterns of glycaemic control at Ghana's National Diabetes Management and Research Centre during the era of the COVID-19 pandemic

BACKGROUND

Maintaining optimal glycaemic control (GC) delays the onset and progression of diabetes-related complications, especially microvascular complications. We aimed to establish the trend and pattern of GC, and its associated factors in persons living with diabetes (PLWD), and to examine the influence of COVID-19 on GC.

METHODS

A retrospective study involving secondary data from 2,593 patients' physical records from the National Diabetes Management and Research Centre (NDMRC) in Accra, extracted from 2015-2021. Growth rate of GC was assessed, and ordinal logistic and Poisson models weighted with Mahalanobis distance matching within propensity caliper were adopted to assess the impact of COVID-19 pandemic on GC. Stata 16.1 was utilized and the significant value set as p≤0.05.

RESULTS

GC pattern indicated a steady deterioration ranging from 38.6% (95%CI = 34.5-42.9) in 2015 to 69.2% (95%CI = 63.5-74.4) in 2021. The overall growth from 2015-2021 was 8.7%. Being a woman and increasing diastolic pressure significantly increase the likelihood of poor glycaemic control (PGC) by 22% and 25%, respectively compared with their respective counterparts [aOR(95%CI = 1.01-1.46 and 1.25(1.10-1.41), respectively]; whilst lower age increased the risk of PGC throughout the years. We found that risk of PGC during the era of COVID-19 was approximately 1.57(95%CI = 1.08-2.30) times significant, whilst the adjusted prevalence ratio (aPR) of PGC during the era of COVID-19 was approximately 64% significantly higher than the era without COVID-19 (aPR = 1.64, 95%CI = 1.10-2.43).

CONCLUSION

GC worsened from 2015-2021, especially during the COVID era. Younger age, uncontrolled blood pressure and/or being a woman were associated with PGC. The NDMRC and other centres that provide specialist healthcare in resource-limited settings, must determine the factors that militate against optimal service delivery in the era of the COVID-19 pandemic, and implement measures that would improve resilience in provision of essential care in the face of shocks.

Nonlinear relationship between glycated hemoglobin and cognitive impairment after acute mild ischemic stroke

BACKGROUND

Stroke is the second most common cause of morbidity and mortality. Even mild stroke survivors have an increased risk of cognitive impairment. Studies have been conducted on the relationship between glycated hemoglobin (HbA1c) and cognitive decline, but the findings have been inconsistent. Therefore, this study examined the link between HbA1c levels and cognitive impairment following acute mild ischemic stroke.

METHODS

Data from 311 patients with acute mild ischemic stroke admitted to Suining Central Hospital, Sichuan Province, China, from January 1, 2015, to December 31, 2018, were evaluated. Fasting venous blood was taken to assess HbA1c levels on the day after admission. Cognitive function was assessed using the Chinese version of the Montreal Cognitive Assessment Scale (MoCA) 3-6 months after stroke onset. We used a generalized additive model and smooth curve fitting (penalty spline method) to assess the nonlinear relationship between HbA1c and poststroke cognitive impairment (PSCI).

RESULTS

This study included 311 patients aged 23 to 96 years old (mean age: 67.37 ± 11.92 years), of whom 198 (63.67%) were men. Among the 311 stroke patients, 120 (38.59%) had PSCI. After adjusting for potential confounders, there was a nonlinear relationship between HbA1c and PSCI, with an inflection point of 8.2. To the left of the inflection point, the effect size, 95% confidence interval, and P value were 0.87, 0.58 to 1.31, and 0.5095, respectively; however, to the right of the inflection point, these numbers were 1.96, 1.08 to 3.58, and 0.0280.

CONCLUSION

We found a nonlinear relationship between HbA1c and PSCI. When HbA1c was greater than 8.2%, HbA1c was positively correlated with PSCI.

Predictors of Healthcare Utilization Among Older Adults with Moderate to Severe Cognitive Limitations in Ghana: A Cross-Sectional Analysis of the WHO Study on Global Ageing and Adult Health (SAGE) Wave 1

BACKGROUND

As the number of older adults in Ghana keeps increasing, so does the prevalence of aging-related diseases and conditions that tend to lead to cognitive decline. However, knowledge on the predicting factors of healthcare utilization among older adults with cognitive limitations is still scarce.

OBJECTIVE

This study examines the predictive factors of healthcare-seeking behavior among older adults with moderate-to-severe cognitive limitations in Ghana.

METHODS

Based on Andersen's behavioral model of health service utilization, the study analyzed data from 3106 older adults with moderate to severe cognitive limitations in Ghana aged 50+ using Bivariate Probit Regression and the Heckman Selection Model.

RESULTS

Results showed that individuals who were aged 75+, living in urban settlements, educated, higher income levels and parents who had some level of education, pension benefits, and both mandatory and voluntary health insurance were more likely to seek inpatient care. Enabling resources such as the national health insurance scheme and other types of medical insurance, household income, pension benefits, and predisposition factors like education influenced outpatient and inpatient healthcare consumption for older adults with moderate to severe cognitive limitations but had little influence on the choice of healthcare facility except for health insurance.

CONCLUSION

Since the healthcare-seeking behavior of older adults with moderate-to-severe cognitive limitations is driven by an amalgamation of several internal and external factors, there is a need for policy change to understand and cautiously incorporate these factors into the decision to improve equitable access to healthcare services for these individuals, as not all sizes fit all in providing quality care for them.

Perspectives of glycemic variability in diabetic neuropathy: a comprehensive review

Diabetic neuropathy is one of the most prevalent chronic complications of diabetes, and up to half of diabetic patients will develop diabetic neuropathy during their disease course. Notably, emerging evidence suggests that glycemic variability is associated with the pathogenesis of diabetic complications and has emerged as a possible independent risk factor for diabetic neuropathy. In this review, we describe the commonly used metrics for evaluating glycemic variability in clinical practice and summarize the role and related mechanisms of glycemic variability in diabetic neuropathy, including cardiovascular autonomic neuropathy, diabetic peripheral neuropathy and cognitive impairment. In addition, we also address the potential pharmacological and non-pharmacological treatment methods for diabetic neuropathy, aiming to provide ideas for the treatment of diabetic neuropathy.

Zhang et al. describe metrics for evaluating glycaemic variability (GV) in clinical practice and summarize the role and related mechanisms of GV in diabetic neuropathy, including cardiovascular autonomic neuropathy, diabetic peripheral neuropathy and cognitive impairment. They aim to stimulate ideas for the treatment of diabetic neuropathy.

Metformin improves cognitive impairment in diabetic mice induced by a combination of streptozotocin and isoflurane anesthesia

To investigate the protective effects of metformin on the diabetic mice with cognitive impairment induced by the combination of streptozotocin (STZ) and isoflurane anesthesia. The isoflurane-anesthetized cognitive impairment model mice were established and then observed via behavioral tests and histopathological examination. Then these model mice were randomly assigned to three groups, which received the PBS, low and high doses of metformin, respectively. The body weight, food and water consumption of model mice were measured every other day. The mechanisms of metformin on ameliorating the cognitive dysfunction were further investigated by histomorphological, biochemical and Western blot analysis. After 14-days treatment of metformin, the diabetic symptoms in STZ-induced diabetic mice were significantly alleviated. Metformin could restore the isoflurane- and STZ-induced hippocampal tissue damage, cognitive and memory impairment in exposed space via improving the oxidative stress, upregulating the contents of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) in the hippocampus tissues of diabetic mice. Furthermore, chronic treatment of metformin significantly down-regulated the expression of AGEs, RAGE, pNF-κB, iNOS, and COX-2. In conclusion, metformin can improve the isoflurane- and STZ-induced cognitive impairment in diabetic mice via improving oxidative stress and inhibiting the AGEs/RAGE/NF-κB signaling pathway.

Diabetes and Cognitive Impairment: A Role for Glucotoxicity and Dopaminergic Dysfunction

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia, responsible for the onset of several long-term complications. Recent evidence suggests that cognitive dysfunction represents an emerging complication of DM, but the underlying molecular mechanisms are still obscure. Dopamine (DA), a neurotransmitter essentially known for its relevance in the regulation of behavior and movement, modulates cognitive function, too. Interestingly, alterations of the dopaminergic system have been observed in DM. This review aims to offer a comprehensive overview of the most relevant experimental results assessing DA’s role in cognitive function, highlighting the presence of dopaminergic dysfunction in DM and supporting a role for glucotoxicity in DM-associated dopaminergic dysfunction and cognitive impairment. Several studies confirm a role for DA in cognition both in animal models and in humans. Similarly, significant alterations of the dopaminergic system have been observed in animal models of experimental diabetes and in diabetic patients, too. Evidence is accumulating that advanced glycation end products (AGEs) and their precursor methylglyoxal (MGO) are associated with cognitive impairment and alterations of the dopaminergic system. Further research is needed to clarify the molecular mechanisms linking DM-associated dopaminergic dysfunction and cognitive impairment and to assess the deleterious impact of glucotoxicity.

Associations of the Glycaemic Control of Diabetes with Dementia and Physical Function in Rural-Dwelling Older Chinese Adults: A Population-Based Study

Purpose

To examine the associations of impaired fasting glucose (IFG) and glycaemic control of diabetes with dementia, global cognitive function and physical function among rural-dwelling Chinese older adults.

Patients and Methods

This population-based cross-sectional study included 4583 participants (age ≥65 years, 57.3% women) living in Yanlou Town, Yanggu County, western Shandong Province, China. In 2018, data were collected through interviews, clinical examinations, neuropsychological tests, and laboratory tests. Diabetes status was defined by self-reported physician-diagnosed diabetes, current use of antidiabetic agents, and fasting blood glucose tests. Global cognitive function was assessed using the Mini-Mental State Examination. Dementia was diagnosed following DSM-IV criteria, and Alzheimer's disease (AD) was diagnosed following the National Institute on Aging-Alzheimer's Association criteria. Physical function was assessed by the Short Physical Performance Battery. Data were analysed using multiple logistic and general linear regression models.

Results

IFG was found in 267 participants, and diabetes was diagnosed in 658 participants (257 with well-controlled diabetes, 401 with poorly controlled diabetes). Dementia was diagnosed in 166 participants (116 with AD), and physical functional impairment was found in 1973 participants. The multi-adjusted odds ratio (OR) of dementia associated with poorly controlled diabetes (vs without IFG or diabetes) was 2.41 (95% CI 1.52-3.84), and the OR of AD associated with poorly controlled diabetes was 2.32 (1.34-4.04). In addition, the adjusted OR of physical functional impairment was 1.40 (1.06-1.85) for well-controlled diabetes and 1.69 (1.35-2.12) for poorly controlled diabetes. However, IFG was not associated with cognitive or physical function.

Conclusion

The glycaemic control status of diabetes patients was associated with cognitive impairment and physical functional impairment.

Connecting vascular aging and frailty in Alzheimer's disease

Aging plays an important role in the etiology of the most common age-related diseases (ARDs), including Alzheimer's disease (AD). The increasing number of AD patients and the lack of disease-modifying drugs warranted intensive research to tackle the pathophysiological mechanisms underpinning AD development. Vascular aging/dysfunction is a common feature of almost all ARDs, including cardiovascular (CV) diseases, diabetes and AD. To this regard, interventions aimed at modifying CV outcomes are under extensive investigation for their pleiotropic role in ameliorating and slowing down cognitive impairment in middle-life and elderly individuals. Evidence from observational and clinical studies confirm the notion that the earlier the interventions are conducted, the most favorable are the effects on cognitive function. Therefore, epidemiological research should focus on the early detection of deviations from a healthy cognitive aging trajectory, through the stratification of adult individuals according to the rate of aging. Here, we review the interplay between vascular and cognitive dysfunctions associated with aging, to disentangle the complex mechanisms underpinning the development and progression of neurodegenerative disorders, with a specific focus on AD.