Diabetes and cognitive decline in elderly African Americans: a 15-year follow-up study

A review of dairy food intake for improving health among black geriatrics in the US

The transition to older adulthood is generally marked by progressive declines in body composition, metabolism, cognitive function, and immunity. For socially disadvantaged geriatric populations such as Black Americans, this life stage may also include additional stressors, including dealing with discrimination, poor access to healthcare, and food insecurity. These types of chronic stressors are linked to a higher allostatic load, which is associated with accelerated biological aging, higher rates of adverse health outcomes, and an overall lower quality of life. Of the numerous factors involved in healthy aging, a growing body of research indicates that consuming a higher quality diet that is rich in fruits, vegetables, whole grains, protein foods, and dairy foods, is one of the most potent factors for helping to protect against age-related disease progression. Among the food groups listed above that are recommended by the 2020-2025 Dietary Guidelines for Americans dairy foods are unique in their ability to provide several of the essential nutrients (e.g., high-quality protein, calcium, potassium, vitamin B12, and vitamin D in fortified products) that are most often inadequately consumed by older Black Americans. However, dairy is the most inadequately consumed food group in the US, with older Black adults consuming fewer than half of the 3 daily recommended servings. Therefore, this review examines the current body of evidence exploring the links between dairy intake and age-related disease risk, with a special focus on health and disparities among older Black Americans. Overall, the evidence from most systematic reviews and/or meta-analyses focused on dairy intake and musculoskeletal health suggest that higher dairy intake across the life span, and especially from fermented and fortified products, is associated with better bone and muscle health outcomes in older adults. The evidence on dairy intake and neurocognitive and immune outcomes among older adults holds significant promise for potential benefits, but most of these results are sourced from individual studies or narrative reviews and are not currently corroborated in systematic reviews or meta-analyses. Additionally, most of the research on dairy intake and age-related disease risk has been performed in White populations and can only be extrapolated to Black populations. Nonetheless, older Black populations who do not meet the DGA recommended 3 servings of dairy per day due to lactose intolerance, restrictive dietary patterns, or for other reasons, are likely falling short of several of the nutritional requirements necessary to support healthy aging.

Potential biomarkers in hypoglycemic brain injury

Oxidative stress is a major underlying mechanism in hypoglycemic brain injury. Several oxidative stress-related proteins were identified through previous proteomics and literature review. The aim of the present study was to evaluate the potential of these proteins as biomarkers in hypoglycemic brain injury. Forty male Sprague Dawley rats were randomly and equally divided into four groups: control, acute hypoglycemia, hypoglycemia resuscitation 24 h, and hypoglycemia resuscitation 7 days. The hypoglycemic brain injury rat model was successfully constructed according to the Auer model. Real-time fluorescent quantitative polymerase chain reaction, western blot analysis, and immunohistochemical staining were used to quantify the expression of oxidative stress-related proteins. We also verified the expression level of selected protein in the brain samples of fatal insulin overdose cases. The expression of oxidative stress-related proteins PEX1/5/12 was down-regulated in hypoglycemic brain injury (P < 0.05), while the expressions of DJ-1 and NDRG1 were up-regulated (P < 0.05). Compared with the control group, the serum oxidative stress indexes SOD and MDA in the acute hypoglycemia group were significantly different (P < 0.01). The expressions of DJ-1 and NDRG1 in the hippocampus, cortex, and hypothalamus of rats were increased (P < 0.05). The expressions of DJ-1 and NDRG1 proteins in the cortex of the autopsy samples of insulin overdose were increased (P < 0.05). Oxidative stress-related proteins showed potential value as specific molecular markers in hypoglycemic brain injury, but further confirmatory studies are needed.

A randomized controlled trial to test the efficacy of a diabetes behavioral intervention to prevent memory decline in older blacks/African Americans with diabetes and mild cognitive impairment

BACKGROUND

The prevalence of dementia in Blacks/African Americans (AAs) is almost twice that of Whites. Inequities in access to health care, socioeconomic conditions, and diabetes contribute to this disparity. Poorly controlled diabetes, which is more prevalent in Blacks/AAs, causes microvascular disease and neurodegeneration and increases dementia risk. Improving glycemic control, therefore, may prevent cognitive decline. To address this issue, we developed Diabetes Regulation for Eyesight and Memory (DREAM), a community health worker (CHW)-led behavioral intervention to improve diabetes self-management and thereby prevent cognitive decline. DREAM consists of home-based diabetes education, goal setting, and telehealth visits with a diabetes nurse educator. Exploratory aims will investigate whether APOE genotype moderates and retinal biomarkers mediate treatment effects. This report describes the trial's rationale, methodology, and study procedures. (clinicaltrials.gov identifier NCT04259047).

METHODS

This randomized controlled trial will test the efficacy of DREAM to prevent decline in memory (primary outcome) in Blacks/AAs aged 65+ with poorly controlled diabetes and Mild Cognitive Impairment (MCI). Two hundred participants will be randomized to DREAM or an attention control condition, and will receive 11 in-home treatment sessions over two years. Outcome data are collected at 6, 12, 18, and 24 months. The primary outcome is verbal learning as measured by Hopkins Verbal Learning Test (HVLT) Total Recall scores. Participants will have retinal imaging at baseline, 12, and 24 months.

CONCLUSIONS

This research aims to prevent cognitive decline in older Blacks/AAs with diabetes and MCI. If successful, this research will preserve health in an underserved population and reduce racial health disparities.

The Relationship of John Henryism With Cognitive Function and Decline in Older Black Adults

OBJECTIVE

This study aimed to investigate the relationship between John Henryism, a psychological trait typified by high-effort active coping that has been associated with adverse health outcomes among Blacks, and cognitive decline.

METHODS

In a cohort of community-dwelling older Black adults ( N = 611), we investigated the relationship between John Henryism and cognitive decline. John Henryism was measured using the John Henryism Active Coping Scale (JHACS), a nine-item validated measure of self-reported high-effort coping (mean [standard deviation] = 16.9 [4.8]; range, 4-27). We implemented a three-step modeling process using mixed-effects models to assess the relationship between the JHACS and global cognitive function as well as five cognitive domains. We adjusted for demographics and for factors known to be associated with cognitive function and decline including vascular risk factors, discrimination, and income.

RESULTS

The trait of high-effort active coping was associated with lower-average cognitive function ( β = -0.07, 95% confidence interval = -0.10 to -0.03), but not with decline. The results remained after further adjustment for experiences of discrimination, income, and vascular risk factors. In domain-specific analyses, we found that the JHACS was associated with baseline levels of working memory, semantic memory, and visuospatial ability, but not decline.

CONCLUSIONS

These results highlight the importance of using culturally specific measures in considering the heterogeneity of cognitive health outcomes in minoritized populations. Understanding how stress responses relate to late-life cognition among older Black adults could help promote aspects of behavioral resilience along with healthful coping responses.

Asian Best Practices for Care of Diabetes in Elderly (ABCDE)

The elderly population with diabetes is diverse with the majority experiencing a decline in physical and mental capabilities, impacting the entire diabetes management process. Therefore, a need for geriatric-specific guidelines, especially for the Asian population, was identified and subsequently developed by an expert panel across government and private institutions from several Asian countries. The panel considered clinical evidence (landmark trials, position papers, expert opinions), recommendations from several important societies along with their decades of clinical experience and expertise, while meticulously devising thorough geriatric-specific tailored management strategies. The creation of the ABCDE best practices document underscores and explores the gaps and challenges and determines optimal methods for diabetes management of the elderly population in the Asian region.

Perceived Stress is Associated with Alzheimer's Disease Cerebrospinal Fluid Biomarkers in African Americans with Mild Cognitive Impairment

BACKGROUND

African Americans (AA) have a higher Alzheimer's disease (AD) prevalence and report more perceived stress than White Americans. The biological basis of the stress-AD link is unclear. This study investigates the connection between stress and AD biomarkers in a biracial cohort.

OBJECTIVE

Establish biomarker evidence for the observed association between stress and AD, especially in AA.

METHODS

A cross-sectional study (n = 364, 41.8% AA) administering cognitive tests and the perceived stress scale (PSS) questionnaire. A subset (n = 309) provided cerebrospinal fluid for measurement of Aβ42, Tau, Ptau, Tau/Aβ42 (TAR), and Ptau/Aβ42 (PTAR). Multivariate linear regression, including factors that confound racial differences in AD, was performed.

RESULTS

Higher PSS scores were associated with higher Ptau (β= 0.43, p = 0.01) and PTAR (β= 0.005, p = 0.03) in AA with impaired cognition (mild cognitive impairment).

CONCLUSION

Higher PSS scores were associated with Tau-related AD biomarker indices in AA/MCI, suggesting a potential biological connection for stress with AD and its racial disparity.

Traumatic brain injury in the homeless: health, injury mechanisms, and hospital course

Primary ObjectiveEstablished literature demonstrates that homeless individuals experience both greater disease burden and risk of experiencing traumatic brain injury (TBI) than the general population. Similarly, shared risk factors for both homelessness and/or TBI may exacerbate the risk of repetitive neurotrauma within homeless populations.Research DesignWe leveraged a state-wide trauma registry, the Pennsylvania Trauma Outcome Study (PTOS), to characterize 609 patients discharged to homeless (58% TBI, 42% orthopedic injury (OI)) in comparison to 609 randomly sampled adult patients discharged to home.Methods and ProceduresWe implemented Chi-square tests to examine preexisting health conditions (PECs), hospital course, and injury mechanisms for both patient groups.Main Outcomes and ResultsHomelessness affects a greater proportion of nonwhite patients, and homeless patients present for care with increased frequencies of psychiatric and substance use PECs, and alcohol-positive TBI. Furthermore, assault impacts a larger proportion of homeless patients, and the window for overnight assault risk resulting in TBI is extended for these patients compared to patients discharged to home.ConclusionGiven the shifting conceptualization of TBI as a chronic condition, identifying homeless patients on admission to trauma centers, rather than retrospectively at discharge, can enhance understanding of the challenges facing the homeless as they age with both a complex neurotrauma history and multimorbidity.

A Link Between Brain Insulin Resistance and Cognitive Dysfunctions: Targeting Ca2+/cAMP Signalling

BACKGROUND

A correlation between cognitive dysfunctions and brain insulin resistance has been established by several clinical and experimental studies. Consistent data support that people diagnosed with brain insulin resistance, resulted from diabetes, have shown an increased risk of presenting cognitive dysfunctions, clinical signs of dementia and depression, then speculating a role of dysregulations related to insulin signalling in these diseases. Furthermore, it is currently discussed that Ca2+ signalling, and its dysregulations, may be a factor which could correlate with brain insulin resistance and cognitive dysfunctions.

OBJECTIVE

Following this, revealing this interplay between these diseases may provide novel insights into the pathogenesis of such diseases.

METHODS

Publications covering topics such as Ca2+ signalling, diabetes, depression and dementia (alone or combined) were collected by searching PubMed and EMBASE.

RESULTS

The controlling of both neurotransmitters/hormones release and neuronal death could be achieved through modulating Ca2+ and cAMP signalling pathways (Ca2+/cAMP signalling).

CONCLUSION

Taking into account our previous reports on Ca2+/cAMP signalling, and considering a limited discussion in the literature on the role of Ca2+/cAMP signalling in the link between cognitive dysfunctions and brain insulin resistance, this article has comprehensively discussed the role of these signalling pathways in this link (between cognitive dysfunctions and brain insulin resistance).

Association of arsenic exposure and cognitive impairment: A population-based cross-sectional study in China

BACKGROUND

The influence of chronic arsenic exposure on cognitive impairment has been explored broadly by previous studies. However, most of them focused mainly on children rather than adults. In addition, in China, studies in this field are not sufficient. To illustrate how long-term arsenic exposure affects cognitive function, we designed a cross-sectional study involving 1556 adults.

METHODS

All of them came from three locations around the Realgar Plant. The cognitive function of the participants was evaluated using a Chinese version of the Mini-mental state Examination (MMSE). The participants' internal arsenic exposure status (hair arsenic concentrations) and the external arsenic exposure status (the distance between the participants' location of residence and the Realgar Plant) were measured.

RESULTS

Our research revealed that both of hair arsenic concentrations and the prevalence of arsenicosis, two important indexes, were significantly higher in the cognitive-impaired (CI) group than in the cognitive-normal (CN) group (P < 0.05). In addition, distance from the Realgar Plant was positively correlated with the MMSE scores and was negatively correlated with the prevalence of cognitive impairment. Moreover, our results demonstrated that there was a negative correlation between hair arsenic concentrations and MMSE scores. We conducted a two-level Logistic regression analysis and further confirmed that even after adjusting for potential confounding variables, arsenicosis retained a risk factor for cognitive impairment (odds ratio (OR) = 1.84, P < 0.05).

CONCLUSIONS

Our results indicated that chronic arsenic exposure could impair adults' cognitive function in a dose-dependent manner. Additionally, arsenicosis could be an independent risk factor for cognitive impairment.

The association between diabetes and cognitive changes during aging

BACKGROUND

Worldwide, we are observing a rising prevalence of dementia and mild cognitive impairments that often co-occur with the heightened incidence of non-communicable diseases in the elderly. It is suggested that type 2 diabetes and defects in glucose metabolism might predispose to poorer cognitive performances and more rapid decline in old age.

METHODS

to address existing knowledge gaps in this area, we systematically reviewed the literature to identify whether patients with type 2 diabetes (T2DM) and pre-diabetes are at a higher risk of poorer cognitive performance, and whether the risk (if any) might affect specific cognitive abilities. We concentrated the review on elderly individuals (65 years or older) at intake. In total, 3251 original articles were retrieved, of which 17 met our inclusion and quality control criteria, which comprised 12 structured questions used to define the articles.

RESULTS

11 of 17 studies found a statistically significant decline in cognition among individuals who had T2DM or pre-diabetes compared to their non-diabetic counterparts. The association between diabetes and cognitive decline was not always clear, and the extent of the cognitive tests used seemed to have the greatest effect on the results.

CONCLUSION

Focusing on a population age 65 years and over, we found insufficient evidence to support an association between pre-diabetes stages and mild cognitive impairment. However, there is consistent evidence to support diabetes as an independent risk factor for low cognitive ability in the elderly. Finally, we found insufficient evidence to support effect of T2DM on distinct cognitive ability due to the scarcity of comparable findings.

Short height and poor education increase the risk of dementia in Nigerian type 2 diabetic women

Introduction

There is urgent need to investigate type 2 diabetes and dementia crosstalk in sub-Saharan African countries with special attention to women who have higher vulnerability. Nigeria which has the highest number of diabetics on the African continent is a good location for the investigation.

Methods

Biophysical parameters, occupation, education, burden of diabetes mellitus, cardiovascular health, and cognition were evaluated in 102 type 2 diabetics and 99 controls.

Results

Short physical stature and lower level of education were hallmarks of diabetes in females. Two dementia scales (Mini–Mental State Examination and six-item Cognitive Impairment Test) showed cognitive impairment status, with the six-item Cognitive Impairment Test scale being more specific and sensitive. Both scales showed correlations with age, education, weight, height, and disease onset, whereas fasten blood glucose was negatively correlated with height and their blood pressure was normal.

Discussion

Height, an easy-to-measure parameter in Nigeria, may reveal increased risk of dementia in poorly educated female Nigerian diabetics, thus helping to improve preventive and therapeutic interventions.

Type 2 diabetes and cognitive dysfunction in minorities: a review of the literature

OBJECTIVES

The purpose of this review was to summarize the current status of knowledge regarding cognitive dysfunction and diabetes in minorities. Literature on the interaction of cognitive dysfunction and diabetes was analyzed to (a) examine the number and characteristics of studies in minority populations; (b) identify tests used to assess cognitive function in diabetes; (c) consider the impact of diabetes on cognitive function; and (d) assess the moderators of the association between diabetes and cognitive function.

DESIGN

A literature review and thematic analysis was conducted. Studies were mapped to describe their design, target population, instruments used, and the physiologic, psychosocial, and socioeconomic findings related to cognitive function and diabetes. Twelve studies met the inclusion criteria.

RESULTS

Hispanics were studied more than any other ethnic group. Rates and degree of cognitive dysfunction were more prevalent in minorities than non-Hispanic whites. Overall, 28 different tests were administered to evaluate cognitive function. There was some variation among findings regarding the relationship of cognitive function and diabetes. Risk for cognitive decline was associated with the diagnosis of diabetes alone, regardless of whether the diabetes was treated or untreated. Higher rates of discrimination were associated with greater cognitive decline Conclusion: Given the context of minority health, there is a potential for higher negative health impact due to the increased prevalence of diabetes and cognitive dysfunction and other related health disparities. Reduction of physiological risk factors for diabetes, consistency in assessment, as well as elimination of structural barriers such as access to care should be helpful in decreasing the incidence of both diabetes and cognitive decline. More research is needed to determine whether the observed differences are modifiable and to identify factors involved in the interaction of diabetes and cognitive decline-not only physiological factors, but factors related to socioeconomic status and quality of life.

Disparities in Health Information-Seeking Behaviors and Fatalistic Views of Cancer by Sexual Orientation Identity: A Nationally Representative Study of Adults in the United States

Purpose: A lack of national data makes it difficult to estimate, but LGB adults appear to have a higher risk of cancer. Although limited research exists to explain the disparity, we aimed to explore potential differences in access to and utilization of health information and in cancer-related beliefs and behaviors. Methods: We used data from the Health Information National Trends Survey 5, Cycle 1 conducted from January 25 through May 5, 2017. Using survey-weighted logistic regression, we explored potential differences in health information-seeking behavior, trusted sources of health care information, engagement with the health care system, awareness of cancer risk factors, cancer fatalism, cancer-related health behaviors, and historical cancer screening between 117 LGB and 2857 heterosexual respondents. Results: LGB respondents were more likely to report looking for information about health or medical topics than heterosexual respondents (adjusted odds ratio [aOR]: 3.12; confidence interval [95% CI]: 1.07-9.06), but less likely to seek health information first from a doctor (aOR: 0.17; 95% CI: 0.06-0.50) after adjusting for age, race, and sex. LGB persons were less likely to report that they trust receiving health or medical information from friends and family and more likely to be worried about getting cancer (aOR: 2.30; 95% CI: 1.04-5.05). Conclusions: Our findings indicate a growing need for the production of tailored cancer prevention and control materials for members of sexual minority groups. More work is needed to understand barriers that LGB populations face in accessing this health information and building informative social support networks.

An Evaluation of Follow-Up Activities of Participants From an Urban Prostate Cancer Screening Event

This study aims to evaluate follow-up activities completed by participants attending community prostate cancer (PCa) screening events. On-site surveys were collected from participants of 17 free PCa screening events from 2007 to 2011 in the St. Louis, MO metropolitan area. Follow-up action surveys were mailed to all on-site participants to assess medical (i.e., made an appointment with a doctor, got additional testing for PCa, made an appointment to be screened) and nonmedical activities (i.e., sought social support, health information-seeking, health behavior modifications) completed after the PCa screening event. Further, t tests and chi-square tests characterized participant information from the on-site survey and within each follow-up activity category for the mailed surveys. Among 1,088 on-site community PCa screening participants, the mean age was 50 years old, 94% were Black, and 30% responded to the mailed follow-up action survey. For the recorded follow-up activities, 65% of participants reported medically reported activities, of which “made an appointment to get a yearly physical” was the most common action (29%). Health behavior modifications were the most common nonmedically related activities (44%). Health information-seeking behaviors were the least reported follow-up action (22%). Men with higher incomes, married, with health insurance, and a primary care physician, most often participated in post-PSA screening activities, namely medically-related and social support activities. Understanding the most common activities completed by participants of a community PCa screening suggests the effectiveness of community events to re-engage underserved populations in the health-care system and provides insight on acceptable health promotion opportunities.

Things Are Changing so Fast: Integrative Technology for Preserving Cognitive Health and Community History

Background and Objectives

Multimodal interventions are increasingly targeting multiple cognitive decline risk factors. However, technology remains mostly adjunctive, largely prioritizes age relevancy over cultural relevancy, and often targets individual health without lasting, community-wide deliverables. Meanwhile, African Americans remain overburdened by cognitive risk factors yet underrepresented in cognitive health and technology studies. The Sharing History through Active Reminiscence and Photo-imagery (SHARP) program increases physical, social, and cognitive activity within a culturally meaningful context that produces community deliverables-an oral history archive and cognitive health education.

Design and Methods

The SHARP application was tested with 19 African Americans ≥55 years, aiming for an easy, integrative, and culturally meaningful experience. The application guided triads in walks 3 times weekly for 6 months in Portland, Oregon's historically Black neighborhoods; local historical images prompted recorded conversational reminiscence. Focus groups evaluated factors influencing technology acceptance-attitudes about technology, usefulness, usability, and relevance to integrating program goals. Thematic analysis guided qualitative interpretation.

Results

Technology acceptance was influenced by group learning, paper-copy replicas for reluctant users, ease of navigation, usefulness for integrating and engaging in health behaviors, relevance to integrating individual benefit and the community priority of preserving history amidst gentrification, and flexibility in how the community uses deliverables. Perceived community benefits sustained acceptance despite intermittent technology failure.

Discussion and Implications

We offer applicable considerations for brain health technology design, implementation, and deliverables that integrate modalities, age, and cultural relevance, and individual and community benefit for more meaningful, and thus more motivated community engagement.

Risk factors for developing dementia in type 2 diabetes mellitus patients with mild cognitive impairment

BACKGROUND

Dementia and cognitive dysfunction have many causes. There is strong evidence that diabetes mellitus (DM) increases the risk of cognitive impairment and dementia. Optimal glycemic control, identification of diabetic risk factors, and prophylactic approach are essential in the prevention of cognitive complications.

AIMS

The main purpose of this study was to establish the cognitive impairment in DM patients, cared for in the Diabetes Center from Timisoara. Also, we investigated the prevalence of dementia in our group as well as the risk factors involved in the progression of mild cognitive impairment (MCI) to dementia.

PATIENTS AND METHODS

We considered a sample of 207 type 2 DM (T2DM) patients, aged between 33 and 81 years, mean 57.49 (±11.37) years. We established the diagnosis of dementia based on the Mini-Mental State Examination (MMSE) test, as well as on the psychological testing, psychiatric and neurological investigations, and imaging tests (computerized tomography and MRI).

RESULTS

A percentage of 42.03% of patients presented MCI, mean age 63 (57.00-71.00) years, being older than patients without MCI, mean age 52.00 (45.00-61.00) years, P<0.001. We observed that diabetes duration was a significant risk factor for developing dementia. Also, patients with MCI presented higher values of body fat than patients without MCI. Moreover, we found that glucose levels, low-density lipoprotein cholesterol levels, the presence of stroke events, and the presence of cardiovascular disease were significant risk factors for MCI conversion to dementia.

CONCLUSION

Patients with T2DM at early to severe stages of MCI are more likely to develop dementia and should be regularly evaluated for their cognitive status. Regular administrations of the MMSE test can be done to detect early stages of MCI development. Also, to reduce the progression of cognitive impairment to dementia, it is worthwhile to give greater importance to glycemic control and overall DM management.

Chronic Health Illnesses as Predictors of Mild Cognitive Impairment Among African American Older Adults

Approximately 5.5 million individuals are diagnosed with Alzheimer's disease (AD) dementia, a number which includes those with mild cognitive impairment and asymptomatic individuals with biomarkers of AD. There is a higher incidence of mild cognitive impairment (MCI) in African American populations as compared to White populations, even when controlling for sociodemographic factors. The existing body of ethnically/racially targeted research on MCI has been limited by few studies with the ability to generalize to African American communities. This study sought to examine whether medical conditions which occur at a higher rate in African American individuals increase the hazard of subsequent MCI development. A secondary data analysis of the National Alzheimer's Coordinating Center Uniform Data Set was employed to examine the associations between health conditions (congestive heart failure, traumatic brain injury, diabetes, hypertension, hypercholesterolemia, B12 deficiency, thyroid disease) and their relationship to MCI. The analytic sample included 2847 participants with 9872 observations. Binary logistic generalized estimating equation modeling was used to examine repeated measures over the course of 1-11 observations. Education was associated with MCI development, specifically those with some college or college graduates (p < 0.001) and more than college (p = 0.002). Female sex was associated with development of MCI (p < 0.001). African Americans with traumatic brain injury (TBI) were more likely to develop MCI (p < 0.001) compared to those with no reports of a TBI. Inactive thyroid conditions decreased the risk of MCI development (p = 0.005) compared to those without thyroid disease. Though vascular factors are often attributed to higher mortality and neurodegeneration in African Americans, congestive heart failure, diabetes, high cholesterol, hypertension, diabetes, nor seizures were associated with an increased risk of MCI development. Findings from this study provide formative data to develop targeted interventions for subsets of the African American community, including those with higher educational levels, those with TBI, and those with a history of thyroid disease. While it may not be possible to prevent MCI development, it is possible to modify lifestyle behaviors contributing to these health conditions, such as falls that are often experienced by older adults. Practitioners can increase awareness, knowledge, and resources relevant to clients.

Changes of glucose levels precede dementia in African-Americans with diabetes but not in Caucasians

INTRODUCTION

Changes in glucose levels may represent a powerful metabolic indicator of dementia in African-Americans with diabetes. It is unclear whether these changes also occur in Caucasians.

METHODS

A secondary data analysis using electronic medical records from 5228 African-Americans and Caucasians aged ≥65 years was carried out. Mixed effects models with repeated serum glucose measurements were used to compare changes in glucose levels between African-Americans and Caucasian patients with and without incident dementia.

RESULTS

African-Americans and Caucasians with diabetes had significantly different changes in glucose levels by dementia status (P < .0001). African-Americans experienced a significant decline in glucose levels before the dementia diagnosis (estimated glucose decline 1.3421 mg/dL per year, P < .0001) than those who did not develop dementia. Caucasians with and without dementia showed stable glucose levels over time (P = .3071).

DISCUSSION

Significant changes in glucose levels precede dementia in African-American patients with diabetes but not in Caucasians.

Antihypertensive Medication and Dementia Risk in Older Adult African Americans with Hypertension: A Prospective Cohort Study

BACKGROUND

African Americans are especially at risk of hypertension and dementia. Antihypertensive medications reduce the risk of cardiovascular events, but may also reduce the risk of dementia.

OBJECTIVE

To assess the longitudinal effects of antihypertensive medications and blood pressure on the onset of incident dementia in a cohort of African Americans.

DESIGN

Prospective cohort.

PARTICIPANTS

1236 community-dwelling patients from an inner-city public health care system, aged 65 years and older, with a history of hypertension but no history of dementia, and who had at least three primary care visits and a prescription filled for any medication.

MAIN MEASURES

Blood pressure was the average of three seated measurements. Dementia was diagnosed using a two-stage design, with a screening evaluation every 2 to 3 years followed by a comprehensive in-home clinical evaluation for those with a positive screen. Laboratory, inpatient and outpatient encounter data, coded diagnoses and procedures, and medication records were derived from a health information exchange.

KEY RESULTS

Of the 1236 hypertensive participants without dementia at baseline, 114 (9%) developed incident dementia during follow-up. Individuals prescribed any antihypertensive medication (n = 816) were found to have a significantly reduced risk of dementia (HR = 0.57, 95% CI 0.37-0.88, p = 0.0114) compared to untreated hypertensive participants (n = 420). When this analysis was repeated including a variable indicating suboptimally treated blood pressure (> 140 mmHg systolic or >90 mmHg diastolic), the effect of antihypertensive medication was no longer statistically significant (HR = 0.65, 95% CI 0.32-1.30, p = 0.2217).

CONCLUSIONS

Control of blood pressure in older adult African American patients with hypertension is a key intervention for preventing dementia, with similar benefits from most of the commonly available antihypertensive medications.

Decreased serum undercarboxylated osteocalcin is associated with cognitive impairment in male patients with type 2 diabetes

BACKGROUND

Basic and clinical researches have suggested that type 2 diabetes (T2DM) is associated with cognitive impairment, and diabetes mellitus increases the risk of cognitive impairment and dementia. Recently, some reports found that undercarboxylated osteocalcin (ucOC) could affect brain functions, and decreased in patients with T2DM. We aimed to investigate the association of serum ucOC with cognitive impairment in T2DM patients.

METHODS

A total of 196 male T2DM patients without medications known to affect bone metabolism or history of bone fracture, aged ≥18years were recruited and divided into impaired cognition group and normal cognition group. We use the scores of Minimum Mental State Examination (MMSE) to evaluate the subjects' cognitive function. Detailed cognitive performance was also evaluated by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Serum ucOC was measured by Enzyme-Linked Immunosorbent Assay (ELISA) kit.

RESULTS

Compared to male T2DM patients with normal cognition, the mean osteocalcin concentrations were significantly lower in male T2DM patients with impaired cognition (P<0.05). RBANS total and all indexes scores were also lower in patients with impaired cognition (all P<0.05). After adjusted effects of confounding factors, serum ucOC was positively correlated with a variety indexes of RBANS except visuospatial/constructional.

CONCLUSIONS

The serum ucOC is positively correlated with RBANS scores in male T2DM patients. It suggests that serum ucOC may be involved in the development and progression of cognitive dysfunction in T2DM patients.

Factors Associated With Medication Engagement Among Older Adults With Diabetes: Systematic Review and Meta-Analysis

Purpose

The purpose of this systematic review and meta-analysis is to explore the factors associated with medication engagement among older adults (≥60 years) with diabetes.

Methods

Five databases (PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and Scopus) were systematically searched to identify studies examining the association between factors and medication engagement among older diabetes patients. A study met inclusion for meta-analysis if the prevalence of medication engagement or factor was reported in ≥2 studies and the frequency or strength of association was either reported or able to be computed. Quality appraisal was performed with the Downs and Black tool.

Results

Of 538 retrieved studies, 33 (20 cohort and 13 cross-sectional) were included for systematic review; of these, 22 met criteria for meta-analysis. Findings from meta-analysis show that women (odds ratio [OR], 0.92; 95% CI, 0.86-0.97), those with depression (OR, 0.73; 95% CI, 0.62-0.87), and those with higher out-of-pocket spending for prescription drugs (OR, 0.87; 95% CI, 0.80-0.94) were less likely to take diabetes medication when compared with men, those without depression, and those with lower out-of-pocket costs, respectively. Older age (OR, 1.13; 95% CI, 1.00-1.27) was associated with better engagement to diabetes medication.

Conclusions

Of 4 identified factors, 2 are modifiable. Recent policy efforts to decrease the cost burden of prescribed medication for older adults, such as Medicare Part D, may remove this barrier to medication engagement. Routine screening for depression among older adults with diabetes should be included as part of usual care to facilitate an integrated treatment approach.

Diabetes and Cognitive Decline in Older Adults: The Ginkgo Evaluation of Memory Study

BACKGROUND

Previous studies have shown that individuals with diabetes exhibit accelerated cognitive decline. However, methodological limitations have limited the quality of this evidence. Heterogeneity in study design, cognitive test administration, and methods of analysis of cognitive data have made it difficult to synthesize and translate findings to practice. We analyzed longitudinal data from the Ginkgo Evaluation of Memory Study to test our hypothesis that older adults with diabetes have greater test-specific and domain-specific cognitive declines compared to older adults without diabetes.

METHODS

Tests of memory, visuo-spatial construction, language, psychomotor speed, and executive function were administered. Test scores were standardized to z-scores and averaged to yield domain scores. Linear random effects models were used to compare baseline differences and changes over time in test and domain scores among individuals with and without diabetes.

RESULTS

Among the 3,069 adults, aged 72-96 years, 9.3% reported diabetes. Over a median follow-up of 6.1 years, participants with diabetes exhibited greater baseline differences in a test of executive function (trail making test, Part B) and greater declines in a test of language (phonemic verbal fluency). For the composite cognitive domain scores, participants with diabetes exhibited lower baseline executive function and global cognition domain scores, but no significant differences in the rate of decline.

CONCLUSIONS

Identifying cognitive domains most affected by diabetes can lead to targeted risk modification, possibly in the form of lifestyle interventions such as diet and physical activity, which we know to be beneficial for improving vascular risk factors, such as diabetes, and therefore may reduce the risk of executive dysfunction and possible dementia.

Longitudinal Cognitive Profiles in Diabetes: Results From the National Alzheimer's Coordinating Center's Uniform Data

BACKGROUND

Diabetes is a risk factor for the development of cognitive impairment and possibly for accelerated progression to Alzheimer disease (AD) and other dementias, though the trajectory of cognitive decline in general and in specfic cognitive domains by diabetes is unclear.

METHODS

Using the National Alzheimer's Coordinating Center's Uniform Data Det (NACC-UDS) to identify cohorts of elders with normal cognition (N = 7,663) and mild cognitive impairment (MCI, N = 4,114), we compared overall cognitive composite and domain specific sub-scores and their progression over time between diabetic and non-diabetic subjects.

RESULTS

Diabetes was more common among those with MCI (14.7%) than among subjects who were cognitively normal (11.7%). In subjects who were cognitively normal, baseline cognitive composite scores, attention, and executive function sub-scores were lower in diabetics than non-diabetics (by 0.098, 0.066, and 0.015 points, respectively). Over time, cognitive composite score showed subtle worsening in non-diabetics (0.025 points every 6 months), with an additional worsening of 0.01 points every 6 months in diabetics compared to non-diabetics. In the MCI groups, baseline cognitive composite as well as attention and executive domain sub-scores were lower in diabetics than non-diabetics (by 0.078, 0.092, and 0.032 points, respectively). Over time, cognitive composite (by 0.103 points every 6 months) and all domain specific sub-scores showed subtle worsening in non-diabetics, but diabetics had significantly slower worsening than non-diabetics on both cognitive composite (by 0.028 points) and domain specific sub-scores.

DISCUSSION

Among elders, diabetes may be associated with lower cognitive performance, primarily in non-memory domains. However it is not associated with continued worsening, suggesting a static deficit with minimal memory involvement. This data suggest that diabetes may contribute more to a vascular profile of cognitive impairment than a profile more typical of AD.

Two novel loci, COBL and SLC10A2, for Alzheimer's disease in African Americans

INTRODUCTION

African Americans' (AAs) late-onset Alzheimer's disease (LOAD) genetic risk profile is incompletely understood. Including clinical covariates in genetic analyses using informed conditioning might improve study power.

METHODS

We conducted a genome-wide association study (GWAS) in AAs employing informed conditioning in 1825 LOAD cases and 3784 cognitively normal controls. We derived a posterior liability conditioned on age, sex, diabetes status, current smoking status, educational attainment, and affection status, with parameters informed by external prevalence information. We assessed association between the posterior liability and a genome-wide set of single-nucleotide polymorphisms (SNPs), controlling for APOE and ABCA7, identified previously in a LOAD GWAS of AAs.

RESULTS

Two SNPs at novel loci, rs112404845 (P = 3.8 × 10-8), upstream of COBL, and rs16961023 (P = 4.6 × 10-8), downstream of SLC10A2, obtained genome-wide significant evidence of association with the posterior liability.

DISCUSSION

An informed conditioning approach can detect LOAD genetic associations in AAs not identified by traditional GWAS.

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

OBJECTIVES

To determine cognitive functions and perceived social support (SS) among individuals with diabetes mellitus (DM), and the effects of SS on the development of cognitive dysfunction (CD). 

METHODS

This cross-sectional study was conducted in 121 patients with DM presenting at the Endocrinology Clinic of Cumhuriyet University Health Services Application and Research Hospital, Sivas, Turkey between April and June 2014. Data were collected utilizing the "Patient Assessment Form", "Standardized Mini Mental State Examination (SMMSE)" and "Multidimensional Scale of Perceived Social Support (MSPSS)".  

RESULTS

The mean score obtained for DM patients from the SMMSE was 21.55±5.7, with 65.3% found to have cognitive impairment. The total mean score of the participants for MSPSS was considered moderate (66.61±14.42). There was a significant positive correlation between cognitive function and SS (r=0.273, p=0.002). It was determined that individuals with CD had low levels of perceived SS, and that insufficient support from families and significant others contributed to the development of CD (p=0.008). 

CONCLUSION

In this study, it was determined that  the cognitive function of individuals with DM was impaired and would improve as the perception of SS increased, and that perceived SS would affect the development of CD. Therefore, health professionals can contribute to the improvement of cognitive function of individuals with DM by facilitating the use of SS sources.

Glucose level decline precedes dementia in elderly African Americans with diabetes

INTRODUCTION

High blood glucose levels may be responsible for the increased risk for dementia in diabetic patients.

METHODS

A secondary data analysis merging electronic medical records (EMRs) with data collected from the Indianapolis-Ibadan Dementia project (IIDP). Of the enrolled 4105 African Americans, 3778 were identified in the EMR. Study endpoints were dementia, mild cognitive impairment (MCI), or normal cognition. Repeated serum glucose measurements were used as the outcome variables.

RESULTS

Diabetic participants who developed incident dementia had a significant decrease in serum glucose levels in the years preceding the diagnosis compared to the participants with normal cognition (P = .0002). They also had significantly higher glucose levels up to 9 years before the dementia diagnosis (P = .0367).

DISCUSSION

High glucose levels followed by a decline occurring years before diagnosis in African American participants with diabetes may represent a powerful presymptomatic metabolic indicator of dementia.

Cognitive decline following incident and preexisting diabetes mellitus in a population sample

OBJECTIVE

To examine if incident and preexisting diabetes mellitus (DM) were associated with cognitive decline among African Americans (AAs) and European Americans (EAs).

METHODS

Based on a prospective study of 7,740 older adults (mean age 72.3 years, 64% AA, 63% female), DM was ascertained by hypoglycemic medication use and Medicare claims during physician or hospital visits, and cognition by performance on a brief battery for executive functioning, episodic memory, and Mini-Mental State Examination (MMSE). Decline in composite and individual tests among those with incident DM, with preexisting DM, and without DM was studied using a linear mixed effects model with and without change point.

RESULTS

At baseline, 737 (15%) AAs and 269 (10%) EAs had preexisting DM. Another 721 (17%) AAs and 289 (12%) EAs had incident DM in old age. Following incident DM, cognitive decline increased by 36% among AAs and by 40% among EAs compared to those without DM. No significant difference was observed between AAs and EAs (p = 0.64). However, cognitive decline increased by 17% among AAs with preexisting DM compared to those without DM, but no increased decline was observed among EAs with preexisting DM. In secondary analyses, faster decline in executive functioning and episodic memory was observed following incident DM.

CONCLUSIONS

In old age, faster cognitive decline was present among AAs and EAs following incident DM, compared to cognitive decline prior to DM, and among those without DM. This underscores the need for stronger prevention and control of DM in old age.

Diabetes mellitus and cognitive impairments

There is strong evidence that diabetes mellitus increases the risk of cognitive impairment and dementia. Insulin signaling dysregulation and small vessel disease in the base of diabetes may be important contributing factors in Alzheimer’s disease and vascular dementia pathogenesis, respectively. Optimal glycemic control in type 1 diabetes and identification of diabetic risk factors and prophylactic approach in type 2 diabetes are very important in the prevention of cognitive complications. In addition, hypoglycemic attacks in children and elderly should be avoided. Anti-diabetic medications especially Insulin may have a role in the management of cognitive dysfunction and dementia but further investigation is needed to validate these findings.

Correlates of Incident Cognitive Impairment in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

OBJECTIVE

To identify approximately 500 cases of incident cognitive impairment (ICI) in a large, national sample adapting an existing cognitive test-based case definition and to examine relationships of vascular risk factors with ICI.

METHOD

Participants were from the REGARDS study, a national sample of 30,239 African-American and White Americans. Participants included in this analysis had normal cognitive screening and no history of stroke at baseline, and at least one follow-up cognitive assessment with a three-test battery (TTB). Regression-based norms were applied to TTB scores to identify cases of ICI. Logistic regression was used to model associations with baseline vascular risk factors.

RESULTS

We identified 495 participants with ICI of 17,630 eligible participants. In multivariable modeling, income (OR 1.83 CI 1.27,2.62), stroke belt residence (OR 1.45 CI 1.18,1.78), history of transient ischemic attack (OR 1.90 CI 1.29,2.81), coronary artery disease(OR 1.32 CI 1.02,1.70), diabetes (OR 1.48 CI 1.17,1.87), obesity (OR 1.40 CI 1.05,1.86), and incident stroke (OR 2.73 CI 1.52,4.90) were associated with ICI.

CONCLUSIONS

We adapted a previously validated cognitive test-based case definition to identify cases of ICI. Many previously identified risk factors were associated with ICI, supporting the criterion-related validity of our definition.

Strategies for research recruitment and retention of older adults of racial and ethnic minorities

HOW TO OBTAIN CONTACT HOURS BY READING THIS ARTICLE INSTRUCTIONS 1.4 contact hours will be awarded by Villanova University College of Nursing upon successful completion of this activity. A contact hour is a unit of measurement that denotes 60 minutes of an organized learning activity. This is a learner-based activity. Villanova University College of Nursing does not require submission of your answers to the quiz. A contact hour certificate will be awarded once you register, pay the registration fee, and complete the evaluation form online at http://goo.gl/gMfXaf. To obtain contact hours you must: 1. Read the article, "Strategies for Research Recruitment and Retention of Older Adults of Racial and Ethnic Minorities" found on pages 14-23, carefully noting any tables and other illustrative materials that are included to enhance your knowledge and understanding of the content. Be sure to keep track of the amount of time (number of minutes) you spend reading the article and completing the quiz. 2. Read and answer each question on the quiz. After completing all of the questions, compare your answers to those provided within this issue. If you have incorrect answers, return to the article for further study. 3. Go to the Villanova website listed above to register for contact hour credit. You will be asked to provide your name; contact information; and a VISA, MasterCard, or Discover card number for payment of the $20.00 fee. Once you complete the online evaluation, a certificate will be automatically generated. This activity is valid for continuing education credit until April 30, 2018. CONTACT HOURS This activity is co-provided by Villanova University College of Nursing and SLACK Incorporated. Villanova University College of Nursing is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's Commission on Accreditation. ACTIVITY OBJECTIVE 1. Identify strategies and barriers for the recruitment and retention of older adults of racial and ethnic minorities in cognitive aging research. DISCLOSURE STATEMENT Neither the planners nor the authors have any conflicts of interest to disclose. The numbers of Hispanic and African American older adults in the United States are expected to increase by 86% and more than 31%, respectively. African American and Hispanic American individuals are more likely than Caucasian individuals to have chronic health conditions, and researchers have argued that these health disparities may contribute to their higher rates of dementia-related illnesses. The current article explores strategies to improve participation in cognitive aging research by older adults, particularly minority older adults. The cultural aspects of cognitive aging are examined, especially the role of stigma and stereotype threat. The perceptions of cognitive aging of African American and Hispanic older adults are also described. Specific strategies are presented that have been successfully implemented to improve recruitment and retention in research targeting minority older adults. Strategies that yielded retention of minority older adults included advertising and marketing a randomized clinical trial, media relations, intervention tailoring, and adaptation of psychometric instruments.

Target risk factors for dementia prevention: a systematic review and Delphi consensus study on the evidence from observational studies

OBJECTIVE

Dementia has a multifactorial etiology, but the importance of individual health and lifestyle related risk factors is often uncertain or based on few studies. The goal of this paper is to identify the major modifiable risk factors for dementia as a first step in developing an effective preventive strategy and promoting healthy late life cognitive functioning.

METHODS

A mixed-method approach combined findings from a systematic literature review and a Delphi consensus study. The literature search was conducted in PubMed and updated an earlier review by the United States National Institutes of Health from 2010. We reviewed the available evidence from observational epidemiological studies. The online Delphi study asked eight international experts to rank and weigh each risk factor for its importance for dementia prevention.

RESULTS

Out of 3127 abstracts, 291 were included in the review. There was good agreement between modifiable risk factors identified in the literature review and risk factors named spontaneously by experts. After triangulation of both methods and re-weighting by experts, strongest support was found for depression, (midlife) hypertension, physical inactivity, diabetes, (midlife) obesity, hyperlipidemia, and smoking, while more research is needed for coronary heart disease, renal dysfunction, diet, and cognitive activity.

CONCLUSIONS

Findings provide good support for several somatic and lifestyle factors and will be used to inform the design of a new multicenter trial into dementia prevention.

The prevalence of diabetes mellitus (DM) type II among Iranian elderly population and its association with other age-related diseases, 2012

DM type II is one of the most common chronic diseases. The objective of this study is to investigate the prevalence of DM and its association with other age-related diseases in Iran, 2012. In this cross-sectional study, people aged 60 years and over were selected using multistage sampling method. Mini-Nutritional Assessment (MNA), Activity of Daily Living (ADL), and Geriatric Depression Scale (GDS-15 items) questionnaires were used. History of common disorders was taken through self-report, medical records and the results of clinical examinations. A total of 1350 old people were studied. DM type II was found in 297 (22.0%) subjects and 371 (27.5%) of subjects were not aware of their DM status. Hypertension (55.6%), high serum cholesterol (51.8%), malnutrition (40.1%), Alzheimer's disease (16.9%), weight loss within past year (16.1%), weight gain within past year (11.7%), frailty (64.6%), insomnia (50.1%), and vision problems (62.6%) were significantly more common in diabetics. Those who were not aware of their status of DM either were between diabetics and non-diabetics or more similar to non-diabetics. Considering high prevalence of age-related diseases among Iranian elderly people, in particular women and those with DM type II, preventive measures are recommended so as to decrease and control DM type II and its consequent complications.

Histone deacetylase inhibitor, trichostatin A, improves learning and memory in high-fat diet-induced cognitive deficits in mice

Metabolic syndrome is increasingly recognized for its effects on cognitive health. Recent studies have highlighted the role of histone deacetylases (HDACs) in metabolic syndrome and cognitive functions. The present study was designed to investigate the possible therapeutic role of a HDAC inhibitor, trichostatin A (TSA), in cognitive impairment associated with metabolic syndrome. To ascertain the mechanisms involved, we fed mice with high-fat diet (HFD) for 4 weeks and examined changes in behavioral and biochemical/oxidative stress markers. Mice subjected to HFD exhibited characteristic features of metabolic disorder, viz., hyperglycemia, hypertriglyceridemia, hypercholesterolemia, and lower high-density lipoprotein (HDL) cholesterol levels. Moreover, these mice showed severe deficits in learning and memory as assessed by the Morris water maze and passive avoidance tasks along with elevated oxidative stress and inflammatory markers in brain homogenates. The observed changes occurred concurrently with reduced brain-derived neurotrophic factor (BDNF). In contrast, the mice treated with the HDAC inhibitor, TSA (0.5 and 1 mg/kg, i.p.), showed a significant and dose-dependent reduction in serum glucose, triglycerides, and total cholesterol along with improvement in HDL-cholesterol levels and learning and memory performance. TSA treatment also results in alleviation of oxidative stress and neuroinflammatory markers. Moreover, TSA significantly augmented the BDNF levels in HFD-fed mice. Thus, based upon these observations, it may be suggested that HDAC inhibition could be a novel therapeutic strategy to combat cognitive impairment associated with metabolic syndrome.

Relationship between depressive symptoms and cognition in older, non-demented African Americans

Knowledge of the relationship between depressive symptoms and cognition in older adults has primarily come from studies of clinically depressed, functionally impaired or cognitively impaired individuals, and in predominately White samples. Limited minority representation in depression research exposes the need to examine these associations in more ethnic/racially diverse populations. We sought to examine the relationship between depressive symptoms and cognition in a sample of non-demented older African Americans recruited from surrounding U.S. cities of New York, Greensboro, Miami, and Nashville (N=944). Depressive symptoms were evaluated with the Geriatric Depression Scale (GDS). Cognition was evaluated with a comprehensive neuropsychological battery. Test scores were summarized into attention, executive function, memory, language, and processing speed composites. Controlling for age, education, reading level, and sex, African American older adults who endorsed more symptoms obtained significantly lower scores on measures of memory, language, processing speed, and executive functioning. Further investigation of the causal pathway underlying this association, as well as potential mediators of the relationship between depressive symptoms and cognitive test performance among older African Americans, such as cardiovascular and cerebrovascular disease, may offer potential avenues for intervention.

A pilot study to examine the correlation between cognition and blood biomarkers in a Singapore Chinese male cohort with type 2 diabetes mellitus

Background

Diabetes is reported to be linked to poorer cognitive function. The purpose of this study is to examine (a) clinical correlation between cognitive function and the biochemical perturbations in T2DM, and (b) the impact of statin treatment on cognitive function in diabetic subjects.

Methods

Forty Singaporean Chinese males with diabetes and twenty Singaporean Chinese males without diabetes were recruited for this study. Twenty-two of the diabetic subjects were on statin therapy and all subjects were non-demented. This was a 2-period non-interventional case-control study in which subjects were assessed for cognitive function in period 1 and blood samples taken over 2 periods, approximately 1 week apart. Blood was collected to determine the level of total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, glucose and insulin. Cognitive performance was measured by a neuropsychological battery covering domains of attention, language, verbal and visual memory, visuomotor speed and executive function. Z-scores were derived for each cognitive domain using the mean and standard deviations (SDs), and they were used to compare between (a) diabetic and non-diabetic groups, and (b) diabetic subjects with and without statin treatment. ANCOVAs with age, education, BMI, and the duration of diabetes as covariates were employed to examine differences in mean score of cognitive domains and subtests between the two groups.

Results

Overall cognitive function was similar among diabetics and age matched non-diabetic controls. Among diabetic statin users, HDL, LDL and total cholesterol were negatively correlated with executive function, whereas peripheral insulin levels and insulin resistance were negatively associated with attention.

Conclusion

Diabetic statin users were likely to have poorer performance in attention and executive function. Increasing levels of the peripheral biomarkers are likely to contribute to poorer cognitive performance.

Epidemiology of diabetes and diabetes complications in the elderly: an emerging public health burden

Diabetes in the elderly is a growing public health burden. Persons with diabetes are living longer and are vulnerable to the traditional microvascular and macrovascular complications of diabetes but also at increased risk for geriatric syndromes. Peripheral vascular disease, heart disease, and stroke all have a high prevalence among older adults with diabetes. Traditional microvascular complications such as retinopathy, nephropathy, and neuropathy also frequently occur. Unique to this older population is the effect of diabetes on functional status. Older adults with diabetes are also more likely to experience geriatric syndromes such as falls, dementia, depression, and incontinence. Further studies are needed to better characterize those elderly individuals who may be at the highest risk of adverse complications from diabetes.

Effects of type 2 diabetes on 12-year cognitive change: results from the Maastricht Aging Study

OBJECTIVE

To examine the effects of baseline and incident diabetes on change in cognitive function over 12 years.

RESEARCH DESIGN AND METHODS

A sample of 1,290 individuals aged ≥ 40 years at baseline, participating in the Maastricht Aging Study, were cognitively tested at baseline, after 6 years, and after 12 years. Of these, 68 participants had type 2 diabetes at baseline, and 54 and 57 had incident diabetes at the 6- and 12-year follow-up, respectively. Changes in performance on tests of information-processing speed, executive function, and verbal memory from baseline to 6- and 12-year follow-up were compared between groups using linear mixed models. Effects of diabetes on cognitive decline were adjusted for demographic variables, history of smoking, alcohol intake, and comorbid conditions, including hypertension, cardiovascular disease, BMI, and depression.

RESULTS

Participants with baseline diabetes showed larger decline in information-processing speed (estimate -7.64; P < 0.01), executive function (21.82; P < 0.01), and delayed word recall (-1.35; P < 0.05) over the 12-year follow-up compared with control subjects. No significant difference in decline was observed for immediate word recall. Compared with control subjects, participants with incident diabetes showed subtle early decline in information-processing speed only. Interestingly, they did not show larger decline in any other cognitive domain.

CONCLUSIONS

Individuals with baseline type 2 diabetes show accelerated cognitive decline, particularly in information-processing speed and executive function, compared with individuals without diabetes. In incident diabetes, decline in speed becomes detectable first, and cognitive decline seems to increase with increasing exposure time.

Low BDNF is associated with cognitive deficits in patients with type 2 diabetes

OBJECTIVE

Studies suggest that brain-derived neurotrophic factor (BDNF) plays an essential role in regulating memory-related neuroplasticity in the hippocampus. Type 2 diabetes (T2DM) is associated with impairment in many domains of cognitive function which may result from reduced BDNF; however, the correlation of BDNF with cognitive impairment in T2DM has not been investigated.

MATERIALS AND METHODS

We compared 208 patients with T2DM to 212 normal controls on serum BDNF and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

RESULTS

Serum BDNF levels were significantly decreased in T2DM patients compared to normal controls (p < 0.001). The total score and nearly all indexes (all p < 0.01) except for attention and visuospatial/constructional indexes (all p > 0.05) of RBANS were markedly lower in T2DM than controls. There was a positive relationship between serum BDNF and delayed memory in patients with T2DM.

CONCLUSION

Our results suggest that BDNF may play a role in the pathophysiology of cognitive deficits, especially delayed memory in T2DM.

Predictors of cognitive decline in 85-year-old patients without cognitive impairment at baseline: 2-year follow-up of the octabaix study

BACKGROUND/RATIONALE

To determine how many 85-year-old community-dwelling patients with good cognitive performance at baseline maintain this level at 2-year follow-up.

METHODS

We realized a longitudinal community-based study including 169 inhabitants. Patients who maintained scores >23 on the Spanish version of the Mini-Mental State Examination (MEC) were compared with the rest.

RESULTS

A total of 144 individuals (85.2%) were found maintaining a MEC score >23. Under the combined criteria 110 (65%) presented no new cognitive decline. Multiple logistic regression analysis showed that maintaining a MEC score >23 was significantly associated with having a higher MEC score at baseline (P < .001, odds ratio 1.280, 95% confidence interval 1.104-1.484).

CONCLUSION

Most oldest-old patients with good cognitive function at baseline maintain this level at 2-year follow-up.

Sociocultural Influences on Diabetes Self-Management Behaviors in Older African Americans

OBJECTIVE

The purpose of this observational study was to describe the associations between cultural beliefs that are prevalent in older African Americans and adherence to diabetes self-management (DSM) behaviors.

METHODS

In a community population of 110 older African Americans with type 2 diabetes, the investigators administered surveys that assess present time orientation (PTO), future time orientation (FTO), and religiosity, as well as exercising habits, reading food labels, and checking blood glucose.

RESULTS

Participants who reported regularly exercising had significantly lower PTO scores and higher FTO and religiosity scores than participants who did not regularly exercise. Similarly, participants who reported reading food labels had lower PTO scores and higher FTO scores but did not differ in religiosity. Participants who reported checking blood glucose levels tended to have higher FTO scores but did not differ in PTO or religiosity. Participants who engaged in all three DSM behaviors had significantly lower PTO scores and higher FTO and religiosity scores.

CONCLUSION

These data indicate that cultural diversity within older African Americans may influence DSM behaviors and contribute to disparities in diabetes outcomes in this high-risk population. Efforts to prevent complications of diabetes might benefit from consideration of these cultural factors.

A high-fat-diet-induced cognitive deficit in rats that is not prevented by improving insulin sensitivity with metformin

AIMS/HYPOTHESIS

We previously demonstrated that animals fed a high-fat (HF) diet for 10 weeks developed insulin resistance and behavioural inflexibility. We hypothesised that intervention with metformin would diminish the HF-feeding-evoked cognitive deficit by improving insulin sensitivity.

METHODS

Rats were trained in an operant-based matching and non-matching to position task (MTP/NMTP). Animals received an HF (45% of kJ as lard; n = 24), standard chow (SC; n = 16), HF + metformin (144 mg/kg in diet; n = 20) or SC + metformin (144 mg/kg in diet; n = 16) diet for 10 weeks before retesting. Body weight and plasma glucose, insulin and leptin were measured. Protein lysates from various brain areas were analysed for alterations in intracellular signalling or production of synaptic proteins.

RESULTS

HF-fed animals developed insulin resistance and an impairment in switching task contingency from matching to non-matching paradigm. Metformin attenuated the insulin resistance and weight gain associated with HF feeding, but had no effect on performance in either MTP or NMTP tasks. No major alteration in proteins associated with insulin signalling or synaptic function was detected in response to HF diet in the hypothalamus, hippocampus, striatum or cortex.

CONCLUSIONS/INTERPRETATION

Metformin prevented the metabolic but not cognitive alterations associated with HF feeding. The HF diet protocol did not change basal insulin signalling in the brain, suggesting that the brain did not develop insulin resistance. These findings indicate that HF diet has deleterious effects on neuronal function over and above those related to insulin resistance and suggest that weight loss may not be sufficient to reverse some damaging effects of poor diet.

Insulin therapy and hypoglycemia

Hypoglycemia is the most important and common side effect of insulin therapy. It is also the rate limiting factor in safely achieving excellent glycemic control. A three-fold increased risk of severe hypoglycemia occurs in both type 1 and type 2 diabetes with tight glucose control. This dictates a need to individualize therapy and glycemia goals to minimize this risk. Several ways to reduce hypoglycemia risk are recognized and discussed. They include frequent monitoring of blood sugars with home blood glucose tests and sometimes continuous glucose monitoring (CGM) in order to identify hypoglycemia particularly in hypoglycemia unawareness. Considerations include prompt measured hypoglycemia treatment, attempts to reduce glycemic variability, balancing basal and meal insulin therapy, a pattern therapy approach and use of a physiological mimicry with insulin analogues in a flexible manner. Methods to achieve adequate control while focusing on minimizing the risk of hypoglycemia are delineated in this article.