Age, gender, and education are associated with cognitive performance in an older Israeli sample with type 2 diabetes

Investigating the impact of remnant cholesterol on new-onset stroke across diverse inflammation levels: Insights from the China Health and Retirement Longitudinal Study (CHARLS)

BACKGROUND

Prior research underscores the significant impact of remnant cholesterol (RC) on stroke occurrence due to its proatherogenic and proinflammatory traits. This study aims to explore diverse risks of new-onset stroke associated with RC, considering distinct inflammation levels in the middle-aged and senior population in China.

METHODS

We analyzed 6509 participants from the China Health and Retirement Longitudinal Study (CHARLS) across four waves (2011-2018). We employed a multivariable Cox proportional hazards regression model, incorporated restricted cubic spline techniques, and conducted sensitivity analyses to evaluate the association among RC, high-sensitivity C-reactive protein (hsCRP), and the risk of new-onset stroke.

RESULTS

Over 7 years, 540 new-onset strokes occurred. Individuals in the highest quartile of RC levels exhibited a heightened risk of new-onset stroke, with a multivariable-adjusted hazard ratio (HR) peaking at 1.50 (95% confidence interval 1.12-2.00, P for trend = 0.021), showing a non-linear correlation (P nonlinearity = 0.049). High hsCRP alone had an adjusted HR of 1.10 (95% CI 0.87-1.39), compared to 1.40 (95% CI 1.00-1.96) for high RC alone. Additionally, concurrent high RC and hsCRP showed an adjusted HR of 1.43 (95% CI 1.05-1.96). Consistency persisted across various hsCRP thresholds, after adjusting for additional parameters, or excluding chronic diseases in the primary model, reinforcing result robustness.

CONCLUSION

Our findings reveal a substantial and non-linear association between higher baseline RC levels and an elevated risk of new-onset stroke. Moreover, elevated levels of both RC and hsCRP jointly pose the highest risk for new-onset stroke, surpassing the risk associated with each factor individually.

Gender differences in the association between physical activity and cognitive subdomains among elders with type 2 diabetes and mild cognitive impairment: a cross-sectional study

OBJECTIVES

The objective of this study was to evaluate the gender differences in the correlation between physical activity (PA) and cognitive subdomains in elderly individuals with type 2 diabetes (T2D) and mild cognitive impairment (MCI).

DESIGN

Cross-sectional study.

SETTING

The research was carried out in communities located in Fuzhou, Fujian Province and Beijing Municipality.

PARTICIPANTS

Community-dwelling elders with T2D and MCI aged 60 years or older were eligible for this study.

PRIMARY OUTCOME MEASURES AND ANALYSES

The weekly PA score was assessed using the International Physical Activity Questionnaire (IPAQ). The cognitive subdomains were evaluated through a battery of cognitive assessments, including the Rey Auditory Verbal Learning Test (RAVLT), Trail Making Test Part B, Digit Symbol Substitution Test (DSST) and the Stroop Color-Word Test (SCWT). Multiple linear regression models were employed to examine the association between PA and cognitive subdomains in both male and female individuals.

RESULTS

In older men, higher total IPAQ score was positively correlated with higher RAVLT (P=0.011) and SCWT (P=0.049). There was a significant interaction between the total PA score and gender in relation to RAVLT (P=0.008) and SCWT (P=0.027). Moreover, there was a positive correlation between moderate-vigorous PA level and RAVLT in older men (P=0.007). Additionally, a positive correlation was found between moderate-vigorous PA level and DSST in older women (P=0.038).

CONCLUSION

In older individuals with T2D and MCI, the association between PA and cognitive subdomains differs between men and women. This discrepancy may impact the customisation of exercise recommendations.

A feasibility study of the combination of intranasal insulin with oral semaglutide for cognition in older adults with metabolic syndrome at high dementia risk- Study rationale and design

INTRODUCTION

We present the rationale and design of a double-blind placebo-controlled feasibility trial combining intranasal insulin (INI) with semaglutide, a GLP-1 receptor agonist, to improve cognition in older adults with metabolic syndrome (MetS) and mild cognitive impairment (MCI). Since both INI and dulaglutide have beneficial effects on the cerebrovascular disease (CVD), we anticipate that improved CVD will underlie the hypothesized cognitive benefits.

METHODS

This 12-months trial will include 80 older adults aged > 60 with MetS and MCI, randomized to 4 groups: INI/oral semaglutide, intranasal placebo/oral semaglutide, INI/oral placebo, and intranasal placebo/oral placebo. Feasibility of combining INI with semaglutide will be tested by examining the ease of use of INI (20IU, twice/day) with semaglutide (14 once daily), adherence, and safety profile are the efficacy of combination therapy on global cognition and neurobiological markers: cerebral blood flow, cerebral glucose utilization, white matter hyperintensities, Alzheimer's related blood biomarkers and expression of insulin signaling proteins measured in brain-derived exosomes. Efficacy will be assessed for the intent-to-treat sample.

DISCUSSION

This feasibility study is anticipated to provide the basis for a multi-center large-scale randomized clinical trial (RCT) of the cognitive benefits of the combination of INI with semaglutide in individuals enriched for CVD and at high dementia risk.

Evaluating memory testing to distinguish dementia severity among White, Black, and Spanish-speaking individuals in the Uniform Data Set (UDS)

INTRODUCTION

Little work has compared the effectiveness of using multiple types of memory tests alone or in combination to distinguish dementia severity in diverse research cohorts including Black individuals and Spanish speakers. Here we evaluate word list and paragraph recall tests to distinguish cognitively normal, mild cognitively impaired, and those with Alzheimer's disease in diverse cohorts.

METHODS

Using Uniform Data Set (UDS) and site-specific supplemental data, logistic regression models and receiver operating characteristic-area under the curve were used to compare paragraph recall versus word list in differentiating among Clinical Dementia Rating (CDR) scale level.

RESULTS

Results reveal high discriminability for all groups and no difference between either test in distinguishing between CDR levels. Combining tests improved discriminability for the whole group but did not for Black individuals or Spanish speakers.

DISCUSSION

Our findings indicate that using multiple memory tests may not improve differentiation between cognitive impairment levels for diverse cohorts. The burden of added testing may be a barrier for maximizing inclusion of under-represented groups in research.

Gender differences in cognitive function and its associated factors among older adults with type 2 diabetes

Diabetes is widely prevalent among older people and can influence accelerated cognitive decline. Gender-based disparities may contribute to variations in cognitive decline. This study examined gender differences in cognitive function and associated factors among older adults with diabetes. A cross-sectional study was conducted involving 318 Taiwanese older adults with type 2 diabetes. Demographic, health, and diabetes-related data were collected, and cognitive neuropsychological tests were evaluated. Compared to men, women with diabetes showed significantly poorer performance in global cognitive function and executive function. Age, years of education, sleep quality, and HbA1c were correlated with domains of cognitive function in men, whereas age, years of education, depressive symptoms, HbA1c, and duration of diabetes were associated with domains of cognitive function among women. Nurses should recognize gender differences in factors associated with cognitive function in older adults with diabetes and should develop individualized interventions to improve patients' cognitive function.

A feasibility study of the combination of intranasal insulin with dulaglutide for cognition in older adults with metabolic syndrome at high dementia risk - Study rationale and design

INTRODUCTION

We present the rationale and design of a double-blind placebo-controlled feasibility trial combining intranasal insulin (INI) with dulaglutide, a GLP-1 receptor agonist, to improve cognition in older adults with metabolic syndrome (MetS) and mild cognitive impairment (MCI). Since both INI and dulaglutide have beneficial effects on the cerebrovascular disease (CVD), we anticipate that improved CVD will underlie the hypothesized cognitive benefits.

METHODS

This 12-months trial will include 80 older adults aged > 60 with MetS and MCI, randomized to 4 groups: INI/dulaglutide injection, intranasal placebo/dulaglutide injection, INI/placebo injection, and intranasal placebo/placebo injection. Feasibility of combining INI with dulaglutide will be tested by examining the ease of use of INI (20IU, twice/day) with dulaglutide (1.5 mg/week), adherence, and safety profile are the efficacy of combination therapy on global cognition and neurobiological markers: cerebral blood flow, cerebral glucose utilization, white matter hyperintensities, Alzheimer's related blood biomarkers and expression of insulin signaling proteins measured in brain-derived exosomes. Efficacy will be assessed for the intent-to-treat sample.

DISCUSSION

This feasibility study is anticipated to provide the basis for a multi-center large-scale randomized clinical trial of the cognitive benefits of the combination of INI with dulaglutide in individuals enriched for CVD and at high dementia risk.

Association of Type 2 Diabetes Mellitus with Cognitive Function in Adults: A Prospective Cohort Study

BACKGROUND

Cognitive role of untreated type 2 diabetes mellitus (T2DM) has been less well substantiated.

OBJECTIVE

We sought to explore the prospective association of T2DM and untreated T2DM with cognitive function among middle-aged and older Chinese adults.

METHODS

Data of 7,230 participants without baseline brain damage, mental retardation, or memory-related diseases in China Health and Retirement Longitudinal Study (CHARLS) from 2011- 2012 to 2015, were analyzed. Fasting plasma glucose and self-reported information on T2DM diagnosis and treatment were assessed. Participants were categorized into normoglycemia, impaired fasting glucose (IFG), and T2DM (including untreated and treated T2DM) groups. Episodic memory and executive function were assessed by modified Telephone Interview for Cognitive Status every two years. We used generalized estimating equation model to examine the association of baseline T2DM status with cognitive function in succeedingyears.

RESULTS

Compared to those with normoglycemia, T2DM was associated with worse overall cognitive function after controlling for demographic variables, lifestyles, follow-up time, major clinical factors, and baseline cognitive function, although the associations were statistically non-significant (β= -0.19, 95% CI: -0.39, 0.00). However, a significant association was mainly observed for those with untreated T2DM (β= -0.26, 95% CI: -0.47, -0.04), especially in the domain of executive function (β= -0.19, 95% CI: -0.35, -0.03). In general, IFG and treated T2DM individuals had similar levels of cognitive function with normoglycemia participants.

CONCLUSION

Our findings supported a detrimental role of untreated T2DM on cognitive function among middle-aged and older adults. Screening and early treatment for T2DM are warranted for maintaining better cognitive function in later life.

CERAD (Consortium to Establish a Registry for Alzheimer's Disease) Neuropsychology Assessment Battery: 35 Years and Counting

BACKGROUND

In 1986, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) was mandated to develop a brief neuropsychological assessment battery (CERAD-NAB) for AD, for uniform neuropsychological assessment, and information aggregation. Initially used across the National Institutes of Aging-funded Alzheimer's Disease Research Centers, it has become widely adopted wherever information is desired on cognitive status and change therein, particularly in older populations.

OBJECTIVE

Our purpose is to provide information on the multiple uses of the CERAD-NAB since its inception, and possible further developments.

METHODS

Since searching on "CERAD neuropsychological assessment battery" or similar terms missed important information, "CERAD" alone was entered into PubMed and SCOPUS, and CERAD-NAB use identified from the resulting studies. Use was sorted into major categories, e.g., psychometric information, norms, dementia/differential dementia diagnosis, epidemiology, intervention evaluation, genetics, etc., also translations, country of use, and alternative data gathering approaches.

RESULTS

CERAD-NAB is available in ∼20 languages. In addition to its initial purpose assessing AD severity, CERAD-NAB can identify mild cognitive impairment, facilitate differential dementia diagnosis, determine cognitive effects of naturally occurring and experimental interventions (e.g., air pollution, selenium in soil, exercise), has helped to clarify cognition/brain physiology-neuroanatomy, and assess cognitive status in dementia-risk conditions. Surveys of primary and tertiary care patients, and of population-based samples in multiple countries have provided information on prevalent and incident dementia, and cross-sectional and longitudinal norms for ages 35-100 years.

CONCLUSION

CERAD-NAB has fulfilled its original mandate, while its uses have expanded, keeping up with advances in the area of dementia.

Does computerized cognitive training improve diabetes self-management and cognition? A randomized control trial of middle-aged and older veterans with type 2 diabetes

AIMS

This randomized control trial compared an adaptive computerized cognitive training intervention with a non-adaptive version. The primary hypothesis predicted better diabetes self-management in type 2 diabetes patients at 6 months post-intervention than baseline in the adaptive arm, with seven secondary outcomes.

METHODS

Intent-to-treat analysis of veterans without dementia aged 55+ from the Bronx, NY and Ann Arbor, MI (N = 90/per arm) used linear mixed model analyses.

RESULTS

Contrary to the hypothesis, only memory showed more improvement in the adaptive arm (p < 0.01). Post-hoc analyses combined the two arms; self-management improved at six-months post-intervention (p < 0.001). Memory, executive functions/attention, prospective memory, diastolic blood pressure, and systolic blood pressure improved (p < 0.05); hemoglobin A1c and medication adherence did not improve significantly.

CONCLUSIONS

The adaptive computerized cognitive training was not substantially better than non-adaptive, but may improve memory. Post-hoc results for the combined arms suggest computer-related activities may improve diabetes self-management and other outcomes for middle-aged and older patients with type 2 diabetes. Practice effects or awareness of being studied cannot be ruled out.

Effect of Advanced Glycation End Products on Cognition in Older Adults with Type 2 Diabetes: Results from a Pilot Clinical Trial

BACKGROUND

Dietary advanced glycation end-products (AGEs) are linked to cognitive decline. However, clinical trials have not tested the effect of AGEs on cognition in older adults.

OBJECTIVE

The aim of the current pilot trial was to examine the feasibility of an intervention to reduce dietary AGEs on cognition and on cerebral blood flow (CBF).

METHODS

The design is a pilot randomized controlled trial of dietary AGEs reduction in older adults with type 2 diabetes. Seventy-five participants were randomized to two arms. The control arm received standard of care (SOC) guidelines for good glycemic control; the intervention arm, in addition to SOC guidelines, were instructed to reduce their dietary AGEs intake. Global cognition and CBF were assessed at baseline and after 6 months of intervention.

RESULTS

At baseline, we found a reverse association between AGEs and cognitive functioning, possibly reflecting the long-term toxicity of AGEs on the brain. There was a significant improvement in global cognition at 6 months in both the intervention and SOC groups which was more prominent in participants with mild cognitive impairment. We also found that at baseline, higher AGEs were associated with increased CBF in the left inferior parietal cortex; however, 6 months of the AGEs lowering intervention did not affect CBF levels, despite lowering AGEs exposure in blood.

CONCLUSION

The current pilot trial focused on the feasibility and methodology of intervening through diet to reduce AGEs in older adults with type 2 diabetes. Our results suggest that participants with mild cognitive impairment may benefit from an intensive dietary intervention.

On the importance of using local tests and local norms in the assessment of memory

The current study compared the assessment of memory with a translated story recall test and its original published norms and an equivalent local test with local norms. Analyses used data from 232 individuals with memory complaints who underwent neuropsychological evaluation at an outpatient memory clinic. One group of participants completed a translated test (N = 126) and another group completed a local test (N = 106). Additionally, participants completed tasks of word list recall, picture naming, and verbal fluency, all having local norms. The results showed that raw scores on the delayed story recall test, and on all other cognitive tasks, did not differ across groups, and the cross-task correlations were significant and similar in size in both groups. Yet, there was an interaction between group and standardized tests scores, whereby the standardized scores on the translated story recall test were equivalent to population mean, whereas all other scores fell below the mean. Conversion of raw scores to the original norms indicated that the performance of individuals with memory complaints was intact, while conversion of scores on a local test to local norms revealed the expected memory impairment. The findings highlight the importance of using local tests and local norms in the assessment of memory.

Design and Feasibility of a Randomized Controlled Pilot Trial to Reduce Exposure and Cognitive Risk Associated With Advanced Glycation End Products in Older Adults With Type 2 Diabetes

Introduction: Advanced glycation end products (AGEs) in diet and serum are positively correlated with chronic conditions such as type 2 diabetes and cognitive decline. Dietary reduction of AGEs was shown to reduce their level in serum and to have a beneficial effect on metabolic biomarkers. However, in part due to limitations of feasibility, clinical trials have not tested its effect on cognition in elderly. The current pilot study examines the feasibility of AGE reduction in elderly with diabetes in terms of recruitment and retention.

Methods: The design is a randomized controlled pilot trial of dietary AGEs in elderly with type 2 diabetes (clinicaltrials.gov NCT02739971). Recruitment followed two stages: we first recruited participants with mild cognitive impairment (MCI), and after expanding inclusion criteria, we later recruited cognitively normal participants with subjective memory complaints (SMCs). Participants were randomized to two arms. Participants in the control arm received standard of care (SOC) guidelines for good glycemic control; those in the experimental arm, in addition to SOC guidelines, were instructed to lower their dietary AGE intake, primarily by changing their cooking methods. Participants were closely followed for dietary adherence over 6 months and evaluated before and after the intervention for adherence to the assigned diet, blood tests, cognitive performance, and brain MRI.

Results: Seventy-five participants (52 with MCI and 23 cognitively normal with SMCs) were recruited primarily through mass mailing and advertising in social media websites. Seventy participants finished the study, and dropout was similar in both groups (7.5% in control vs. 5.7% in intervention, p = 0.757). The majority (57.5%) of participants in the AGEs-lowering arm showed very high adherence with the dietary guidelines.

Discussion: Targeting feasible lifestyle modifications in high-risk populations could prevent substantial cases of cognitive decline. Observational evidence supports that AGEs may contribute to cognitive decline; however, the cognitive effect of reducing AGEs exposure has yet to be evaluated in a randomized controlled trial (RCT). The results of our pilot trial delineate a methodology including effective recruitment strategies, population of choice, and ways to assure high adherence during lifestyle modifications, and significantly advance progress toward a definitive and well-powered future RCT.

Recruitment of Older Veterans with Diabetes Risk for Alzheimer's Disease for a Randomized Clinical Trial of Computerized Cognitive Training

BACKGROUND

Type 2 diabetes mellitus (T2DM) is prevalent in the general United States population, and in the veteran population. T2DM has consistently been linked to increased risk for cognitive impairment, dementia, and Alzheimer's disease. Computerized cognitive training (CCT) is practical and inexpensive cognitive interventions that is an alternative to medication.

OBJECTIVE

To report the recruitment methods and challenges to date in an ongoing two-site randomized controlled trial (RCT) of CCT on cognitive function and T2DM management in an older non-demented veteran population.

METHODS

Veterans are recruited primarily by targeted mailings or by direct contact at clinics and presentations.

RESULTS

From 1,459 original contacts, 437 expressed initial interest, 111 provided informed consent, and 97 completed baseline assessments. Participants from the two VA Medical Centers differed in demographics and baseline characteristics. Comparing recruitment methods, the proportion of individuals contacted who were ultimately consented was significantly less from mailings (5%) than other sources (20%), primarily face- to-face clinic visits (χ2 (1) = 38.331, p < 0.001).

CONCLUSIONS

Mailings are cost-effective, but direct contact improved recruitment. Not using or lacking access to computers and ineligibility were major reasons for non-participation. Within-site comparisons of demographically diverse sites can address confounding of demographic and other site differences.

Association of Brain-Derived Neurotrophic Factor With Cognitive Function: An Investigation of Sex Differences in Patients With Type 2 Diabetes

OBJECTIVE

Although a reduction in brain-derived neurotrophic factor (BDNF) has been implicated as a cause of cognitive impairment in type 2 diabetes mellitus (T2DM), the role of sex in moderating this effect has not been explored.

METHODS

We compared the difference in serum BDNF and performance on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) between 96 men and 134 women with T2DM. We compared this with the difference in serum BDNF and performance in the control group (104 men, 144 women).

RESULTS

Patients with T2DM performed worse on most RBANS indices (η = 0.372, all p < .05); within T2DM patients, men performed worse than women on the delayed memory score (74.1 (12.1) versus 79.9 (11.5), p = .002) and on the total score (71.4 (11.5) versus 76.5 (10.8), p = .025). Serum BDNF was lower in patients with T2DM versus controls (7.5 (2.7) ng/ml versus 11.5 (2.7) ng/ml, p < .001), and in men compared with women (6.9 (2.4) versus 7.9 (2.8), p = .024). Serum BDNF levels positively correlated with delayed memory score in patients with T2DM (β = 0.19, p = .007). However, this association was only observed in women, not in men (pinteraction = 0.04). Among healthy controls, no sex differences were noted in either RBANS or BDNF levels (η = 0.04, Cohen's d < 0.163, all p > .05).

CONCLUSIONS

Our results show sex differences in poorer cognitive performance, lower BDNF concentration, and their relationship in T2DM patients, suggesting that female sex may be a protective factor for cognitive decline in T2DM patients. However, the findings should be regarded as preliminary because of the cross-sectional design and chronicity of the diabetes.

Findings of a Pilot Study Investigating the Effects of Mediterranean Diet and Aerobic Exercise on Cognition in Cognitively Healthy Older People Living Independently within Aged-Care Facilities: The Lifestyle Intervention in Independent Living Aged Care (LIILAC) Study

BACKGROUND

Cognitive decline and Alzheimer disease are more prevalent in our aging population. Modifiable risk factors, such as diet and sedentary lifestyle, have been proposed as key to potentially ameliorating cognitive decline. Both exercise and Mediterranean diet (MedDiet) have been linked to reduced levels of cardiovascular disease and other comorbidities. Higher levels of exercise and MedDiet adherence may prove to be cognitively protective, both individually and synergistically.

OBJECTIVES

The aim was to investigate the effect of a 6-mo program of MedDiet, exercise, and a combination of both, on cognition, mood, and general health in older persons living independently in aged-care communities.

METHODS

The Lifestyle Intervention in Independent Living Aged Care (LIILAC) Study (ACTRN12614001133628) involved 102 participants, aged 60-90 y, who were randomly assigned to 1 of 4 intervention groups. Change in overall memory performance was assessed as the primary outcome. Additionally, changes in cognitive task performance, as well as mood, wellness, cardiovascular function, and blood biomarkers, were investigated.

RESULTS

While there was no significant change in overall memory performance, there was a significant improvement in spatial working memory performance in the combined exercise and diet group, relative to controls. This combined intervention group also showed an overall improvement in their emotional state, as assessed by the Depression Anxiety Stress Scale, as did the exercise-only group.

CONCLUSIONS

This research indicates that diet and exercise programs have the potential to improve aspects of cognition and mood in an aging population. However, given the lower than optimal sample size and lack of resources to reinforce the interventions during the trial, further larger randomized controlled trials are required to substantiate whether the introduction of diet and exercise programs into independent-living facilities is a viable method to preserve cognitive health in older people. This trial was registered at www.ANZCTR.org.au ACTRN 12614001133628 (LIILAC Study).

Associations of hemoglobin A1c with cognition reduced for long diabetes duration

Introduction

Associations of some risk factors with poor cognition, identified prior to age 75, are reduced or reversed in very old age. The Protected Survivor Model predicts this interaction due to enhanced survival of those with extended risk factor duration. In a younger sample, this study examines the association of cognition with the mean hemoglobin A1c risk factor over the time at risk, according to its duration.

Methods

The interaction of mean hemoglobin A1c (average = 9.8%), evaluated over duration (average = 116.8 months), was examined for overall cognition and three cognitive domains in a sample of 150 “young-old” veterans (mean age = 70) with type 2 diabetes.

Results

The predicted interactions were significant for overall cognition and attention, but not executive functions/language and memory.

Discussion

Findings extend the Protected Survivor Model to a “young-old” sample, from the very old. This model suggests focusing on individuals with good cognition despite prolonged high risk when seeking protective factors.

Cognitive Reserve and Executive Functions in Adults with Type 2 Diabetes

BACKGROUND

Adults with type two diabetes mellitus (DM2) show cognitive deficits within the executive function domain. The detrimental effects of DM2 over executive function (EF) performance may be mediated by factors such as cognitive reserve (CR). CR mediates cognitive performance by delaying the appearance of clinical symptoms from subjacent brain pathology or attenuating the severity of such symptoms. Our main goal was to study the effects of CR on executive functions of adults with DM2.

METHODS

Data from a total of 1,034 adults were included (362 women, 672 men). Subjects were categorized into four groups: subjects with DM2 and high CR (n = 235), control subjects with high CR (n = 265), subjects with DM2 and low CR (n = 298), and control subjects with low CR (n = 236). CR was quantified through 3 proxies: education, occupational complexity, and leisure activities. Executive functions were evaluated through visual scanning, verbal fluency, and backwards counting tasks. First, a series of four one-way ANOVAs was performed where group was included as a between-subject factor and executive function as a dependent variable. Second, a hierarchical multiple regression analysis was conducted to assess the weight of each CR proxy on EF performance.

RESULTS

CR level significantly affected all executive function scores independently of the diabetes status. Hierarchical regression analyses indicated that years of education accounted for most of the variance in the model for executive function performance. In this study, we found that there is a significant effect of CR on executive function performance of DM2 subjects and education is the most important CR proxy.

APOE Variant (rs405509) might Modulate the Effect of Sex and Educational Level on Cognitive Impairment Risk in a Taiwanese Population

Education, sex, and the APOE-rs405509 variant are associated with Alzheimer’s disease and cognitive performance. We investigated if the rs405509 TT, TG, and GG genotypes modulate the effect of sex and education on cognitive impairment in Taiwanese adults. Data on cognitive health (defined by Mini-Mental State Examination (MMSE) scores) and rs405509 were from Taiwan Biobank. Participants included 2105 men and 2027 women with a mean age of 64 years. Education below university level was significantly associated with lower MMSE scores. The odds ratios (ORs) were 1.82; 95% confidence interval (CI) 1.38–2.41 for senior high school, 3.39; 95% CI 2.50–4.59 for junior high school, and 11.94; 95% CI 9.91–15.50 for elementary school and below (p-trend < 0.05). The association between MMSE score and sex was significant only in the lowest educational group (elementary and below), with lower odds of having a low MMSE score in men compared to women (OR = 0.51; 95% CI 0.34–0.77). After stratification by rs405509 genotypes, this association was significant only among TT genotype carriers (OR = 0.481; CI = 0.253–0.915). In conclusion, a significant association between MMSE score and sex was observed in the lowest educational group, especially among carriers of rs405509 TT genotypes.

Age Modulates the Association of Caffeine Intake With Cognition and With Gray Matter in Elderly Diabetics

BACKGROUND

The association between caffeine and cognitive performance has not been tested in older individuals with type 2 diabetes (T2D). Its association with brain volume in T2D has been tested only in animals.

METHODS

We examined the association of caffeine with cognitive function and brain volume in a sample of elderly diabetics participating in the Israel Diabetes and Cognitive Decline Study (n = 638) and the moderating effect of age on this association. In a subsample (n = 185) with magnetic resonance imaging, we also examined these associations with gray and white matter volumes (GM/WM).

RESULTS

Using linear regression adjusting for cognition-related covariates, we found that higher caffeine intake was associated with better function in overall cognition (p = .018), attention/working memory (p = .002), executive functioning (p = .047), and semantic categorization (p = .026). Interaction analyses of caffeine intake with age were significant for semantic categorization (p = .025), and approached significance for overall cognition (p = .066). This association was driven by the older group (above-median) for whom the association of caffeine intake with semantic categorization (p = .001), attention/working memory (p = .007), executive functioning (p = .005), and overall cognition (p = .002) were significant. In the magnetic resonance imaging subsample, there was an interaction (p = .034) of caffeine intake with age for GM volume; in the older group, higher caffeine intake was associated with greater GM volume (β = .198, p = .033).

CONCLUSIONS

Caffeine intake may have a beneficial role in cognitive functioning of elderly adults with T2D, which may be moderated by age. Greater GM volume may be a mechanism underlying the association of higher caffeine intake with better cognitive function.

Association between Diabetes and Cognitive Function among People over 45 Years Old in China: A Cross-Sectional Study

Objectives: The aim of this study is to identify the relationship between diabetes status including characteristics of diabetes and cognition among the middle-aged and elderly population (≥45 years) in China. Methods: A sample of 8535 people who participated in the China Health and Retirement Longitudinal Study (CHARLS) from June 2011 to March 2012 was analyzed. Two cognitive domains including episodic memory and executive function were measured through questionnaires. People were classified into four groups: no diabetes, controlled diabetes, untreated diabetes, treated but uncontrolled diabetes. Weighted multiple regression model was conducted to explore the association between diabetes and cognition in full sample as well as three different age groups (45–59, 60–74, ≥75). Adjustments were made for demographics and cardiovascular risk factors. Results: After adjusting several covariates, untreated diabetes (β = −0.192, p < 0.05) was significantly associated with episodic memory. In the age group of 45–69 years, untreated diabetes (β = −0.471, p < 0.05) and HbA1c level (β = −0.074, p < 0.05) were significantly associated with episodic memory. When adjusting for cardiovascular risk factors, all correlations were non-significant. Conclusion: The cross-sectional study suggests that untreated diabetes and HbA1c are the potential risk factor for cognitive impairment, and these associations are more significant in the age group of 45–59 years old. Cardiovascular factors are important mediating factors in the pathway between diabetes and cognitive impairment. More longitudinal studies are needed to confirm these associations.

Effects of Regular Physical Activity on the Cognitive Performance of Type 2 Diabetic Patients: A Systematic Review

BACKGROUND

Cognitive decline has been shown to be associated with long-term type 2 diabetes mellitus (T2DM). This review analyzes the present literature to ascertain the role of regular physical activity (PA) for the functioning of the diabetic brain.

METHODS

PubMed was systematically searched for relevant publications up to July 2017.

RESULTS

Four cross-sectional, one longitudinal observational, and nine interventional studies with a total of ∼7000 T2DM subjects are included in this review. Some significant positive relationships between the PA level of T2DM patients and their performance in several cognitive tests are reported in the cross-sectional studies. The longitudinal observational study implies a higher risk for developing dementia/mild cognitive impairment in T2DM patients with low PA behavior. Some significantly improved cognitive test results are reported for T2DM patients following physical training (PT) in six interventional studies. The quality of most of the training studies is low due to small sample sizes and/or missing control groups.

DISCUSSION

PT may potentially contribute to improving the cognitive performance in T2DM patients. Additional high-quality studies with standardized cognitive assessments are needed to further determine the dose-effect relationships between PA and cognitive performance in T2DM patients.

Obese adolescents with type 2 diabetes perform worse than controls on cognitive and behavioral assessments

BACKGROUND

Children with type 1 diabetes demonstrate worse cognitive performance compared with their peers. Little is known regarding the cognitive and behavioral performance in obese adolescents with type 2 diabetes.

METHODS

Cross sectional evaluation of 20 obese adolescents with type 2 diabetes and 20 healthy adolescents was performed in Cincinnati, Ohio. Cognitive tests that included measures of processing speed, working memory, verbal and semantic fluency and parent reports of executive function and problem behavior were compared. Academic achievement and the relationship between cognitive/behavioral scores and diabetes duration and diabetes control (hemoglobin A1c) were assessed in the type 2 diabetes group only.

RESULTS

The type 2 diabetes group had mean duration of diabetes of 2.8 ± 2.2 yr and hemoglobin A1c of 7.9 ± 2.2%. Adolescents with type 2 diabetes scored lower than controls on tests of working and verbal memory and processing speed (all p < 0.05) and worse for Internalizing, Externalizing, and Total Problems behaviors on the Child Behavior Checklist (all p < 0.05). Adolescents with type 2 diabetes scored below the population mean in academic achievement, most notably calculation. Working memory and processing speed were negatively correlated with duration of diabetes (r = -0.50 and -0.47, respectively, p < 0.05).

CONCLUSIONS

Obese youth with type 2 diabetes score poorly compared with controls on multiple assessments of cognitive function and adaptive behavior. Further work is needed to determine if these effects are driven by obesity, diabetes or other demographic and socioeconomic risk factors.

Age Effects on Cognitive and Physiological Parameters in Familial Caregivers of Alzheimer's Disease Patients

OBJECTIVES

Older familial caregivers of Alzheimer's disease patients are subjected to stress-related cognitive and psychophysiological dysfunctions that may affect their quality of life and ability to provide care. Younger caregivers have never been properly evaluated. We hypothesized that they would show qualitatively similar cognitive and psychophysiological alterations to those of older caregivers.

METHOD

The cognitive measures of 17 young (31-58 years) and 18 old (63-84 years) caregivers and of 17 young (37-57 years) and 18 old (62-84 years) non-caregiver controls were evaluated together with their salivary cortisol and dehydroepiandrosterone (DHEA) levels, as measured by radioimmunoassays and ELISA assays of brain-derived neurotrophic factor (BDNF) in serum.

RESULTS

Although younger caregivers had milder impairments in memory and executive functions than older caregivers, their performances fell to the same or lower levels as those of the healthy older controls. Decreases in DHEA and BDNF levels were correlated with the cognitive dysfunctions observed in the older and younger caregivers, respectively. Cortisol at 10PM increased in both caregiver groups.

DISCUSSION

Younger caregivers were prone to cognitive impairments similar to older caregivers, although the degree and the neuropsychological correlates of the cognitive dysfunctions were somewhat different between the two groups. This work has implications for caregiver and care-recipient health and for research on the neurobiology of stress-related cognitive dysfunctions.

Statin Use is Associated with Better Cognitive Function in Elderly with Type 2 Diabetes

The pleiotropic contribution of statins on cognition is uncertain. From 840 patients in the cohort from the Israel Diabetes and Cognitive Decline Study, we identified 61 non-statin users and compared them with 45 patients who had used statins at least 90% of the time. Analysis of covariance was performed to compare mean cognitive z-scores between statin users and non-users while adjusting for socio-demographic, diabetes-related, and cardiovascular covariates which included change in cholesterol by year. Overall cognition, memory, and executive function was found to be significantly better in statin users (p <  0.0008). This suggests a positive effect of statins on cognitive function of type 2 diabetes patients that is independent of cholesterol levels.

Neuropsychological Test Performance in Cognitively Normal Spanish-speaking Nonagenarians with Little Education

To find associations of age, sex, and education with neuropsychological test performance in cognitively normal Spanish-speaking Costa Rican nonagenarians with little education; to provide norms; and to compare their performance with similar Puerto Ricans. For 95 Costa Ricans (90-102 years old, 0-6 years of education), multiple regression assessed associations with demographics of performance on six neuropsychological tests. Analyses of covariance compared them with 23 Puerto Ricans (90-99 years old). Younger age and being female-but not education-were associated with better performance on some neuropsychological tests, in particular episodic memory. The Puerto Ricans performed better on learning and memory tasks. In cognitively intact Spanish-speaking nonagenarians with little or no education, education did not affect test performance. Additional studies of the effect of education on cognitive performance are warranted in other samples with extremely low education or old age. National differences in performance highlight the importance of group-specific norms.

Shorter adult height is associated with poorer cognitive performance in elderly men with type II diabetes

We studied the relationship of adult body height with five cognitive outcomes (executive functioning, semantic categorization, attention/working memory, episodic memory, and an overall cognition measure) in 897 cognitively normal elderly with type 2 diabetes. Regression analyses controlling for sociodemographic, cardiovascular, and diabetes-related risk factors and depression demonstrated that in males, shorter stature was associated with poorer executive functioning (p = 0.001), attention/working memory (p = 0.007), and overall cognition (p = 0.016), but not with episodic memory (p = 0.715) or semantic categorization (p = 0.948). No relationship between height and cognition was found for females. In cognitively normal type 2 diabetes male subjects, shorter stature, a surrogate for early-life stress and poor nutrition, was associated with cognitive functions.

Glycemic control, inflammation, and cognitive function in older patients with type 2 diabetes

OBJECTIVE

Glycated hemoglobin (HbA1c) and C-reactive protein (CRP) have been associated with cognitive impairment independently. However, it is unclear if their combination exacerbates poor cognitive function. We assessed whether long-term glycemic level and glycemic variability modulate the association of systemic inflammation with cognitive function, in a sample of cognitively normal older people with type 2 diabetes.

METHODS

A retrospective cohort study of 777 randomly selected participants from ~11,000 patients in the Maccabi Healthcare Services Diabetes Registry, as part of the Israel Diabetes and Cognitive Decline study. Subjects averaged 18 (±9.4) HbA1c measures in the Maccabi Healthcare Services Registry, which were used to calculate long-term glycemic level (HbA1c-mean) and glycemic variability (HbA1c-standard deviation (SD)). Linear regression models assessed the interactions of CRP, a marker of systemic inflammation, with HbA1c-mean and HbA1c-SD on subjects' performance in tests of Memory, Executive Functions, Attention, and Semantic Categorization.

RESULTS

Quadratic interactions of CRP with HbA1c-SD approached significance for executive functions and overall cognition. However, after Bonferroni adjustment, none of the interactions of CRP with HbA1c were statistically significant. In partial correlations according to HbA1c-SD tertiles, CRP was weakly correlated in the middle tertile with decreased performance in the domains of semantic categorization (r = -0.166, p = 0.011), executive functions (r = -0.136, p = 0.038), and overall cognition (r = -0.157, p = 0.016).

CONCLUSIONS

Glycated hemoglobin does not substantially modulate the association of CRP with cognition in a sample of cognitively normal, community dwelling older people with relatively well-managed type 2 diabetes.

Decision making, central coherence and set-shifting: a comparison between Binge Eating Disorder, Anorexia Nervosa and Healthy Controls

BACKGROUND

Several studies have investigated the cognitive profile in patients with Anorexia Nervosa (AN) and Bulimia Nervosa (BN); on the contrary few studies have evaluated it in patients with Binge Eating Disorder (BED). The purpose of this study was to compare decision making, central coherence and set-shifting between BED and AN patients.

METHODS

A battery of neuropsychological tests including the Iowa Gambling Task (IGT), the Rey-Osterrieth Complex Figure Test (RCFT), the Wisconsin Card Sorting Test (WCST), the Trial Making Task (TMT) and the Hayling Sentence Completion Task (HSCT) were administered in a sample of 135 women (45 AN, 45 BED, 45 Healthy Controls [HC]). Furthermore, Beck Depression Inventory (BDI) was administered to evaluate depressive symptoms. Years of education, age, Body Mass Index (BMI) and depression severity were considered as covariates in statistical analyses.

RESULTS

BED and AN patients showed high rates of cognitive impairment compared to HC on the domains investigated; furthermore, the cognitive profile of BED patients was characterised by poorer decision making and cognitive flexibility compared to patients with AN. Cognitive performance was strongly associated with depressive symptoms.

CONCLUSIONS

In the present sample, two different neurocognitive profiles emerged: a strong cognitive rigidity and a central coherence based on the details was predominant in patients with AN, while a lack of attention and difficulty in adapting to changes in a new situation seemed to better describe patients with BED. The knowledge of the different cognitive profiles of EDs patients may be important for the planning their psychotherapeutic intervention.

Glycemia and cognitive function in metabolic syndrome and coronary heart disease

OBJECTIVE

Higher hemoglobin A1c (HbA1c) is associated with lower cognitive function in type 2 diabetes. To determine whether associations persist at lower levels of dysglycemia in patients who have established cardiovascular disease, cognitive performance was assessed in the Targeting INflammation Using SALsalate in CardioVascular Disease (TINSAL-CVD) trial.

METHODS

The age-adjusted relationships between HbA1c and cognitive performance measured by the Mini-Mental State Examination, Digit Symbol Substitution Test, Rey Auditory Verbal Learning Test, Trail Making Test, and Categorical Verbal Fluency were assessed in 226 men with metabolic syndrome and established stable coronary artery disease.

RESULTS

Of the participants, 61.5% had normoglycemia, 20.8% had impaired fasting glucose, and 17.7% had type 2 diabetes. HbA1c was associated with cognitive function tests of Digit Symbol Substitution Test, Rey Auditory Verbal Learning Test, Trail Making Test, and Categorical Verbal Fluency (all P < .02), but not the Mini-Mental State Examination. In an age-adjusted model, a 1% (11 mmol/mol) higher HbA1c value was associated with a 5.9 lower Digit Symbol Substitution Test score (95% confidence interval [CI], -9.58 to -2.21; P < .0001); a 2.44 lower Rey Auditory Verbal Learning Test score (95% CI, -4.00 to -0.87; P < .0001); a 15.6 higher Trail Making Test score (95% CI, 5.73 to 25.6; P < .0001); and a 3.71 lower Categorical Verbal Fluency score (95% CI, -6.41 to -1.01; P < .02). In a multivariate model adjusting for age, education, and cardiovascular covariates, HbA1c remained associated with cognitive function tests of Rey Auditory Verbal Learning Test (R(2) = 0.27, P < .0001), Trail Making Test (R(2) = 0.18, P < .0001), and Categorical Verbal Fluency (R(2) = 0.20, P < .0001), although association with the Digit Symbol Substitution Test was reduced.

CONCLUSIONS

Higher HbA1c is associated with lower cognitive function performance scores across multiple domain tests in men with metabolic syndrome and coronary artery disease. Future studies may demonstrate whether glucose lowering within the normative range improves cognitive health.

The association of duration of type 2 diabetes with cognitive performance is modulated by long-term glycemic control

OBJECTIVES

It is unclear why duration of type 2 diabetes (T2D) is associated with increased cognitive compromise. High hemoglobin A1c (HbA1c) has also been associated with dementia, and is the primary contributor to T2D complications. Here we investigated whether the association of duration of T2D with cognitive functioning is modulated by HbA1C levels.

METHODS

This study examined nondemented community-dwelling T2D elderly (N = 897) participating in the Israel Diabetes and Cognitive Decline study, who were assessed with a broad neuropsychological battery. Subjects were all from the Maccabi Healthcare Services, which has a Diabetes Registry with complete HbA1c measurements since 1998. Partial correlations were performed to examine the modulating effect of HbA1c on the relationship of duration of T2D with five cognitive measures, controlling for sociodemographic and cardiovascular risk factors.

RESULTS

An interaction of duration of T2D with HbA1c was associated with executive functioning (p = 0.006), semantic categorization (p = 0.019), attention/working memory (p = 0.011), and overall cognition (p = 0.006), such that the associations between duration of T2D and cognitive impairment increased as HbA1c levels increased-but not for episodic memory (p = 0.984).

CONCLUSIONS

Because duration of T2D was associated with cognition in higher HbA1c levels and overall no associations were found in lower HbA1c levels, our results suggest that individuals with T2D may limit their risk of future cognitive decline by maintaining long-term good glycemic control.