Abdominal fat depots are related to lower cognitive functioning and brain volumes in middle-aged males at high Alzheimer's risk

OBJECTIVE

High BMI, which poorly represents specific fat depots, is linked to poorer cognition and higher dementia risk, with different associations between sexes. This study examined associations of abdominal fat depots with cognition and brain volumes and whether sex modifies this association.

METHODS

A total of 204 healthy middle-aged offspring of Alzheimer's dementia patients (mean age = 59.44, 60% females) underwent abdominal magnetic resonance imaging to quantify hepatic, pancreatic, visceral, and subcutaneous adipose tissue and to assess cognition and brain volumes.

RESULTS

In the whole sample, higher hepatic fat percentage was associated with lower total gray matter volume (β = -0.17, p < 0.01). Primarily in males, higher pancreatic fat percentage was associated with lower global cognition (males: β = -0.27, p = 0.03; females: β = 0.01, p = 0.93) executive function (males: β = -0.27, p = 0.03; females: β = 0.02, p = 0.87), episodic memory (males: β = -0.28, p = 0.03; females: β = 0.07, p = 0.48), and inferior frontal gyrus volume (males: β = -0.28, p = 0.02; females: β = 0.10, p = 0.33). Visceral and subcutaneous adipose tissue was inversely associated with middle frontal and superior frontal gyrus volumes in males and females.

CONCLUSIONS

In middle-aged males at high Alzheimer's dementia risk, but not in females, higher pancreatic fat was associated with lower cognition and brain volumes. These findings suggest a potential sex-specific link between distinct abdominal fat with brain health.

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.

Poor self-rated health is associated with faster cognitive decline and greater small vessel disease in older adults with type 2 diabetes

OBJECTIVE

Self-rated health (SRH) is a predictor for poor health outcomes and cognition. Older adults with type 2 diabetes mellitus (T2D) have multi-morbidity and greater cognitive impairment. In the present study we investigated the association of SRH with cognitive decline and brain pathology in older adults with T2D.

METHODS

Participants (n = 1122) were from the Israel Diabetes and Cognitive Decline study, and SRH was categorised as low (n = 202), moderate (n = 400) or high (n = 520). Cognition was measured by four cognitive domains: episodic memory, executive functions, language, and attention/working memory. Global cognition was the average of the cognitive domains. Statistical models adjusted for sociodemographic, cardiovascular, and clinical variables. In a randomly selected subsample (n = 230) that had magnetic resonance imaging, we examined relationships between baseline SRH and brain characteristics (white matter hyperintensities [WMHs], hippocampal, and total grey matter [GM] volumes).

RESULTS

Low SRH was associated with a decline in executive functions, which accelerated over time when compared to high SRH (est = -0.0036; p = <0.001). Compared to high SRH, low SRH was associated with a faster decline in global cognition (est = -0.0024; p = 0.009). Low SRH at baseline was associated with higher volumes of WMHs (est = 9.8420; p < 0.0008). SRH was not associated with other cognitive domains, or with hippocampal and total GM.

CONCLUSIONS

Low SRH is associated with cognitive decline in T2D older adults and may serve as a risk assessment. WMHs may represent an underlying mechanism.

Neuroticism is associated with increase in depression symptoms over time in older adults with type 2 diabetes

OBJECTIVES

The likelihood of depression symptoms in those with type 2 diabetes (T2D) is high. Psychological risk factors enhancing comorbidity of depression symptoms in T2D are yet to be determined. The present study examines the cross-sectional and longitudinal relationship between personality traits and distinct depression dimensions in older adults with T2D.

METHODS

Participants were older adults (age ≥65yeas) with T2D from the Israel Diabetes and Cognitive Decline (IDCD) study (N = 356), with complete data on depression [Geriatric Depression Scale (GDS) - 15 item version] and its dimensions- namely, dysphoric mood, apathy, hopelessness, memory complains and anxiety, and on personality [Big Five Inventory (BFI)]. Logistic and mixed linear regression models examined cross-sectional and longitudinal associations while adjusting for socio-demographics, cognition, cardiovascular and diabetes-related factors.

RESULTS

Cross-sectionally, high neuroticism was associated with high scores in total GDS and in all depression-dimensions, except memory complaints. Higher extroversion was associated with lower total GDS and with lower scores on all depression dimensions, except anxiety. High levels of neuroticism were associated with increase in total number of depression symptoms over time.

CONCLUSIONS

In older adults with T2D, neuroticism and extroversion are associated with most depression dimensions suggesting that these traits relate to a global depression symptomatology rather than to any specific dimension or phenomenology. High neuroticism was associated with increase in depression symptoms over time, highlighting its role in the development of depression symptoms in older adults with T2D.

[SLEEP MONITORING FOR PREDICTION OF MAJOR DEPRESSION RECURRENCE IN PATIENTS AT HIGH RISK - A PROSPECTIVE STUDY]

INTRODUCTION

Objective: To examine the feasibility of sleep monitoring using an innovative wearable technology, as a predictive tool for MDE (major depressive episode) recurrence in high risk patients.

Decrease in Gait Speed Over Time Is Associated With Increase in Number of Depression Symptoms in Older Adults With Type 2 Diabetes

BACKGROUND

We examined the cross-sectional and longitudinal relationships of motor functions with depression in older adults with type 2 diabetes (T2D).

METHODS

Participants (n = 984) were from the longitudinal Israel Diabetes and Cognitive Decline (IDCD) study. They were initially cognitively normal and underwent evaluations of motor functions (grip strength and gait speed) and of depression (using the 15-item version of the Geriatric Depression Scale [GDS]) approximately every 18 months. We applied Hierarchical Linear Mixed Models (HLMM) to investigate the associations between motor functions and depression adjusting for sociodemographic, cardiovascular factors, overall cognitive score, and subjective report of exhaustion.

RESULTS

Participants' baseline characteristics were 72 (±5) years of age (59.6% males), 13 (±4) years of education, Mini-Mental Status Exam (MMSE) score of 28.01 (±1.78), and a GDS score of (2 ± 2.00), consistent with normal cognitive status and lack of major affective symptomatology. Slower gait speed at baseline was associated with higher GDS scores (p = .001) and with their increase over time (p = .049). A decrease in walking speed from baseline was associated with an increase in GDS scores (p = .015). Lower grip strength at baseline was associated with higher GDS scores (p = .002), but not with trajectories in GDS scores over time. A faster decrease in grip strength from baseline was associated with a faster increase in GDS scores (p = .022).

CONCLUSIONS

Both gait speed and grip strength are cross-sectionally associated with depression. However, only gait speed and its decrease over time can potentially be used to predict incident depression symptoms, thus facilitating the introduction of depression prevention strategies.

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.

Neural correlates of subjective cognitive decline in adults at high risk for Alzheimer's disease

Introduction

Recently, interest has emerged in subjective cognitive decline (SCD) as a potential precursor to Alzheimer's disease (AD) dementia. Whether individuals with SCD harbor brain alterations in midlife, when AD-related pathology begins, is yet to be elucidated. Furthermore, the role of apolipoprotein ε4 (APOE ε4) allele, a robust AD risk factor, in the relationship between SCD and brain alterations is unknown. We examined whether APOE genotype modulates the association of SCD with brain measures in individuals at high AD risk.

Methods

Middle-aged adults with parental history of AD dementia underwent magnetic resonance imaging (MRI) and the Memory Functioning Questionnaire. Regression analysis tested the extent to which SCD was associated with activation during an functional MRI (fMRI) working-memory task, and white-matter microstructure. APOE ε4 genotype was tested as a moderator.

Results

Among APOE ε4 carriers, but not among non-carriers, SCD was associated with higher activation in the anterior cingulate (p = 0.003), inferior, middle, and superior frontal cortices (p = 0.041, p = 0.048, p = 0.037, respectively); and with lower fractional anisotropy in the uncinate fasciculus (p = 0.002), adjusting for age, sex, and education.

Conclusion

In middle aged, cognitively normal individuals at high AD risk, higher SCD was associated with greater brain alterations possibly reflecting incipient AD pathology. When accompanied by a family history of AD and an APOE ε4 allele, SCD may have important clinical value, allowing a window for early intervention and for participants' stratification in AD prevention clinical trials.

Consumption of Ultra-Processed Food and Cognitive Decline among Older Adults With Type-2 Diabetes

BACKGROUND

Ultra-processed food (UPF) consumption is related to increased morbidity and mortality. However, knowledge on its association with cognitive function is lacking. In this longitudinal study, we examined the associations between UPF intake and cognitive decline in older adults with type-2 diabetes (T2D).

METHODS

The sample included initially nondemented T2D older adults (≥65 years), from the Israel Diabetes and Cognitive Decline study, who had complete information on nutrition at baseline and at least 3 cognitive assessments (mean follow-up 5.3 ± 1.5 years). Nutritional intake was evaluated by a validated Food-Frequency Questionnaire, and foods were categorized as UPF based on NOVA classification. Percent of calories from UPF were calculated from total caloric consumption in total and specific food groups. Mixed effect models were used to examine the link between UPF intake (top vs bottom quartiles) and change in cognitive function overall and in specific domains, adjusting for potential confounders.

RESULTS

Of the total sample (N = 568; mean age 71.3 ± 4.5 years, 60% men), 141 consumed >31% kcal from UPF (top quartile). Greater intake of ultra-processed meat was associated with a faster decline in executive functions and global cognition (β = -0.041 ± 0.013; p = .002 and β = -0.026 ± 0.010; p = .011, respectively). Additionally, consumption of ultra-processed oils/spreads was associated with faster decline in executive functions and global cognition (β = -0.037 ± 0.014; p = .006 and β = -0.028 ± 0.010; p = .009, respectively). Total UPF consumption and UPF-derived from dairy products and bread/pastries/starch were not associated with cognitive change.

CONCLUSION

This study suggests that a high intake of ultra-processed meat and oils/spreads may be associated with accelerated cognitive decline in older individuals with T2D.

Physical Activity Is Associated with Slower Cognitive Decline in Older Adults with Type 2 Diabetes

BACKGROUND

Physical activity is associated with slower cognitive decline in old age. Type 2 diabetes (T2d) is a risk factor for dementia and cognitive decline. Physical activity protects against several T2d complications. Yet, little is known about the contribution of physical activity to cognitive health among the elderly with T2d.

OBJECTIVES

To examine the association between physical activity and cognitive decline in older adults with T2d.

DESIGN

This is a prospective longitudinal study using data from the Israel Diabetes and Cognitive Decline (IDCD) study.

SETTING

ICDC study (N=1,213), is a population-based cohort of adults over the age of 65, diagnosed with type 2 diabetes, who were cognitively normal at baseline and followed up every 18 months.

PARTICIPANTS

Participants with at least one follow-up assessment who were in the same physical activity group consistently and had complete demographic data.

MEASUREMENTS

Physical activity was measured using Minnesota Leisure Time Activity Questionnaire, cognitive functioning was measured using a broad neuropsychological assessment measuring Executive Functioning, Attention/Working Memory, Semantic Categorization and Episodic Memory.

RESULTS

Participants were classified into physical activity groups based on self-reported physical activity at baseline and all follow ups: "active" - participation in recreational physical activity (n=286); "non-active"- the only physical activity was walking from place to place (n=93) and "sedentary" (n=19). Linear mixed effects models were applied to adjust for key demographic and cardiovascular risk factors. Participants were 72.4 (SD 4.6) years old, had 13.3 (SD 3.6) years of education, and 163 (41%) were female. In the fully adjusted model, compared to the non-active group the active group had significantly slower rate of decline in Global Cognition (p=0.005), Executive Functioning (p=.014), and Attention/Working Memory (p=.01). There were no significant group differences for Semantic Categorization (p=.17) and Episodic Memory (p=.88).

CONCLUSIONS

Among initially cognitively normal and independent older adults with T2d, a physically active lifestyle was associated with a slower rate of cognitive decline. Future research should examine whether promoting physical activity may prevent or delay onset of dementia in this high-risk population.

Alzheimer’s Disease Polygenic Risk Score Is Not Associated With Cognitive Decline Among Older Adults With Type 2 Diabetes

Objectives

Multiple risk loci for late-onset Alzheimer’s disease (LOAD) have been identified. Type 2 diabetes (T2D) is a risk factor for cognitive decline, dementia and Alzheimer’s disease (AD). We investigated the association of polygenic risk score (PRS) for LOAD with overall cognitive functioning and longitudinal decline, among older adults with T2D.

Methods

The study included 1046 Jewish participants from the Israel Diabetes and Cognitive Decline (IDCD) study, aged ≥ 65 years, diagnosed with T2D, and cognitively normal at baseline. The PRS included variants from 26 LOAD associated loci (at genome-wide significance level), and was calculated with and without APOE. Outcome measures, assessed in 18 months intervals, were global cognition and the specific domains of episodic memory, attention/working memory, executive functions, and language/semantic categorization. Random coefficient models were used for analysis, adjusting for demographic variables, T2D-related characteristics, and cardiovascular factors. Additionally, in a subsample of 202 individuals, we analyzed the association of PRS with the volumes of total gray matter, frontal lobe, hippocampus, amygdala, and white matter hyperintensities. Last, the association of PRS with amyloid beta (Aβ) burden was examined in 44 participants who underwent an 18F-flutemetamol PET scan.

Results

The PRS was not significantly associated with overall functioning or decline in global cognition or any of the specific cognitive domains. Similarly, following correction for multiple testing, there was no association with Aβ burden and other brain imaging phenotypes.

Conclusion

Our results suggest that the cumulative effect of LOAD susceptibility loci is not associated with a greater rate of cognitive decline in older adults with T2D, and other pathways may underlie this link.

Greater intake of the MEDI diet is associated with better cognitive trajectory in older adults with type 2 diabetes

AIMS

To determine associations of three dietary patterns (Mediterranean (MEDI) diet, the Dietary Approaches to Stop Hypertension (DASH) diet and the Mediterranean- DASH Intervention for Neurodegenerative Delay (MIND) diet) with cognitive decline in older adults with type 2 diabetes mellitus (T2D).

METHODS

This is a longitudinal observational study. Participants (N = 960) from the Israel Diabetes and Cognitive Decline (IDCD) study were included in this study. A multivariable-adjusted model including all three dietary patterns concurrently was developed to investigate their independent effect on cognitive decline.

RESULTS

The mean follow up was 4.1 ± 2.1 years. While high adherence to both the MIND and the MEDI diet was associated with a slower decline, in the multivariable model only the associations of higher MEDI diet intake with greater decline in global cognition and in executive functions remained significant (β = 0.013, SE = 0.006; P = 0.042; β = 0.001, SE = 0.008, Pv = 0.023 respectively).

CONCLUSIONS

In older adults with T2D, adherence to the MEDI is related to better cognitive trajectory. Diet is a meaningful factor in the path linking T2D and cognition.

Psychosis as a Treatment Target in Dementia: A Roadmap for Designing Interventions

Psychotic phenomena are among the most severe and disruptive symptoms of dementias and appear in 30% to 50% of patients. They are associated with a worse evolution and great suffering to patients and caregivers. Their current treatments obtain limited results and are not free of adverse effects, which are sometimes serious. It is therefore crucial to develop new treatments that can improve this situation. We review available data that could enlighten the future design of clinical trials with psychosis in dementia as main target. Along with an explanation of its prevalence in the common diseases that cause dementia, we present proposals aimed at improving the definition of symptoms and what should be included and excluded in clinical trials. A review of the available information regarding the neurobiological basis of symptoms, in terms of pathology, neuroimaging, and genomics, is provided as a guide towards new therapeutic targets. The correct evaluation of symptoms is transcendental in any therapeutic trial and these aspects are extensively addressed. Finally, a critical overview of existing pharmacological and non-pharmacological treatments is made, revealing the unmet needs, in terms of efficacy and safety. Our work emphasizes the need for better definition and measurement of psychotic symptoms in dementias in order to highlight their differences with symptoms that appear in non-dementing diseases such as schizophrenia. Advances in neurobiology should illuminate the development of new, more effective and safer molecules for which this review can serve as a roadmap in the design of future clinical trials.

Trajectories of depression symptoms over time differ by APOE4 genotype in older adults with type 2 diabetes

OBJECTIVES

The APOE-ε4 genotype has been associated with old-age depression, but this relationship has been rarely investigated in type 2 diabetes (T2D) older adults, who are at significantly increased risk for depression, a major contributor to T2D complications. We examined whether trajectories of depression symptoms over time differ by APOE-ε4 genotype in older adults with T2D.

METHODS

Participants (n = 754 [13.1% APOE-ε4 carrier]s) were from the longitudinal Israel Diabetes and Cognitive Decline (IDCD) study. They were initially cognitively normal and underwent evaluations of depression approximately every 18 months using the 15-item version of the Geriatric Depression Scale (GDS) and the depression subscale of the Neuropsychiatric Inventory (NPI). APOE was defined as a dichotomy of ε4 carriers and non-carriers. We used Hierarchical Linear Mixed Models (HLMM) that modeled the effects of APOE status on repeated GDS and NPI-depression scores in an unadjusted model (Model 1), adjusting for demographic factors (Model 2) and additionally adjusting for cardiovascular factors and global cognition (Model 3).

RESULTS

Participants' mean age was 71.37 (SD = 4.5); 38.2% female. In comparison to non-carriers, APOE-ε4 carriers had lower mean GDS scores (β = -0.46, p = 0.018) and lower NPI-depression scores (β = -0.170, p = 0.038) throughout all study follow period. The groups did not differ in the slope of change over time in GDS (β = -0.005, p = 0.252) or NPI-depression (β = -0.001, p = 0.994) scores. Additional adjustment for cardiovascular factors and global cognition did not alter these results.

CONCLUSIONS

In older adults with T2D, APOE-ε4 carriers have less depressive symptoms in successive measurements suggesting they may be less susceptible to depression.

The Israel Registry for Alzheimer's Prevention (IRAP) Study: Design and Baseline Characteristics

BACKGROUND

Family history of Alzheimer's disease (AD) is associated with increased dementia-risk.

OBJECTIVE

The Israel Registry for Alzheimer's Prevention (IRAP) is a prospective longitudinal study of asymptomatic middle-aged offspring of AD patients (family history positive; FH+) and controls (whose parents have aged without dementia; FH-) aimed to unravel the contribution of midlife factors to future cognitive decline and dementia. Here we present the study design, methods, and baseline characteristics.

METHODS

Participants are members of the Maccabi Health Services, 40-65 years of age, with exquisitely detailed laboratory, medical diagnoses and medication data available in the Maccabi electronic medical records since 1998. Data collected through IRAP include genetic, sociodemographic, cognitive, brain imaging, lifestyle, and health-related characteristics at baseline and every three years thereafter.

RESULTS

Currently IRAP has 483 participants [mean age 54.95 (SD = 6.68) and 64.8% (n = 313) women], 379 (78.5%) FH+, and 104 (21.5%) FH-. Compared to FH-, FH+ participants were younger (p = 0.011), more often males (p = 0.003) and with a higher prevalence of the APOE E4 allele carriers (32.9% FH+, 22% FH-; p = 0.040). Adjusting for age, sex, and education, FH+ performed worse than FH-in global cognition (p = 0.027) and episodic memory (p = 0.022).

CONCLUSION

Lower cognitive scores and higher rates of the APOE E4 allele carriers among the FH+ group suggest that FH ascertainment is good. The combination of long-term historical health-related data available through Maccabi with the multifactorial information collected through IRAP will potentially enable development of dementia-prevention strategies already in midlife, a critical period in terms of risk factor exposure and initiation of AD-neuropathology.

Physical fitness mediates the association between age and cognition in healthy adults

BACKGROUND

Physical fitness is an important contributor to healthy aging that improves cognition. Older adults who engage in cardiorespiratory fitness activities show less cognitive decline.

AIMS

To examine whether physical fitness acts as a potential protective mechanism shielding against the negative associations between age and cognition. Specifically, we examined whether physical fitness mediates the relationship between age and processing speed.

METHODS

114 (M = 63.80, SD = 10.63) senior executives completed a computerized cognitive battery composed of four processing speed tasks. Level of physical fitness was assessed on a treadmill stress test and reported in metabolic equivalents (METs).

RESULTS

Older age was associated with slower processing speed (r = 0.25, p = 0.007), whereas greater physical fitness was associated with faster processing speed (r = -0.30, p = 0.001). Path analysis indicated that the association between age and processing speed was fully mediated by the level of physical fitness (Indirect effect: β = 0.10, p = 0.008; Direct effect: β = 0.16, p = 0.20).

CONCLUSIONS AND DISCUSSION

The findings indicate that physical fitness is a strong mediator of the relationship between age and processing speed and imply that physical fitness makes a major contribution to cognitive reserve during the aging process. The results may suggest that the decrease in physical fitness during aging may partially account for slower cognitive processing.

Specific Dimensions of Depression Have Different Associations With Cognitive Decline in Older Adults With Type 2 Diabetes

OBJECTIVE

Depression is highly frequent in older adults with type 2 diabetes and is associated with cognitive impairment, yet little is known about how various depression dimensions differentially affect cognition. We investigated longitudinal associations of specific depression dimensions with cognitive decline.

RESEARCH DESIGN AND METHODS

Participants (N = 1,002) were from the Israel Diabetes and Cognitive Decline study, were ≥65 years of age, had type 2 diabetes, and were not experiencing dementia at baseline. Participants underwent a comprehensive neuropsychological battery at baseline and every 18 months thereafter, including domains of episodic memory, attention/working memory, semantic categorization/language, and executive function, and Z-scores of each domain were averaged and further normalized to calculate global cognition. Depression items from the 15-item Geriatric Depression Scale were measured at each visit and subcategorized into five dimensions: dysphoric mood, withdrawal-apathy-vigor (entitled apathy), anxiety, hopelessness, and memory complaint. Random coefficients models examined the association of depression dimensions with baseline and longitudinal cognitive functioning, adjusting for sociodemographics and baseline characteristics, including cardiovascular risk factors, physical activity, and use of diabetes medications.

RESULTS

In the fully adjusted model at baseline, all dimensions of depression, except for anxiety, were associated with some aspect of cognition (P values from 0.01 to <0.001). Longitudinally, greater apathy scores were associated with faster decline in executive function (P = 0.004), a result that withstood adjustment for multiple comparisons. Associations of other depression dimensions with cognitive decline were not significant (P > 0.01).

CONCLUSIONS

Apathy was associated with a faster cognitive decline in executive function. These findings highlight the heterogeneity of depression as a clinical construct rather than as a single entity and point to apathy as a specific risk factor for cognitive decline among older adults with type 2 diabetes.

Deterioration in Motor Function Over Time in Older Adults With Type 2 Diabetes is Associated with Accelerated Cognitive Decline

OBJECTIVE

Type 2 diabetes (T2D) is associated with motor impairments and a higher dementia risk. The relationships of motor decline with cognitive decline in T2D older adults has rarely been studied. Using data from the Israel Diabetes and Cognitive Decline study (N = 892), we examined associations of decline in motor function with cognitive decline over a 54-month period.

METHODS

Motor function measures were strength (handgrip) and gait speed (time to walk 3 m). Participants completed a neuropsychologic battery of 13 tests transformed into z-scores, summarized into 4 cognitive domains: episodic memory, attention/working memory, executive functions, and language/semantic categorization. The average of the 4 domains' z-scores defined global cognition. Motor and cognitive functions were assessed in 18-months intervals. A random coefficients model delineated longitudinal relationships of cognitive decline with baseline and change from baseline in motor function, adjusting for sociodemographic, cardiovascular, and T2D-related covariates.

RESULTS

Slower baseline gait speed levels were significantly associated with more rapid decline in global cognition (P = .004), language/semantic categorization (P = .006) and episodic memory (P = .029). Greater decline over time in gait speed was associated with an accelerated rate of decline in global cognition (P = .050), attention/working memory (P = .047) and language/semantic categorization (P<.001). Baseline strength levels were not associated with cognitive decline but the rate of declining strength was associated with an accelerated decline in executive functions (P = .025) and language/semantic categorization (P = .006).

CONCLUSION

In T2D older adults, the rate of decline in motor function, beyond baseline levels, was associated with accelerated cognitive decline, suggesting that cognitive and motor decline share common neuropathologic mechanisms in T2D.

Sleep Monitoring Using WatchPAT Device to Predict Recurrence of Major Depression in Patients at High Risk for Major Depression Disorder Recurrence: A Case Report

Background: Major depressive disorders are strongly correlated with alterations in sleep pattern and architecture, including changes in the Rapid Eye Movement (REM) phase. However, it is still unknown whether sleep alterations precede other depression-related symptoms, particularly in patients with recurrent depressive episodes at relapse risk. Case Presentation: We initiated a study aimed at examining the value of ambulatory sleep monitoring using a WatchPAT device, in predicting recurrence of Major depression. Depression was assessed monthly with the Beck Depression Inventory version II (BDI-II). Here we present the case of a 63 years old woman, with a history of recurrent depressive episodes. AT the time of recruitment, she was asymptomatic, she experienced recurrence of Major depression 3 months into the study. We observed a significant reduction of the Rem Latency parameters 5 weeks prior to BDI-II score increase, reflecting major depressive episode recurrence. Conclusion: Though our results are preliminary, they suggest that ambulatory sleep monitoring can be used as a simple and accessible tool, predicting recurrence of Major Depressive episodes in patients at high risk, thus enabling early treatment intervention.

Executive functioning of older adults with bipolar disorder

OBJECTIVES

Despite their impact on daily functioning, we have limited understanding of the executive functioning of older adults with bipolar disorder (OABD). Even less is known about the possible differences in the executive functioning of OABD and older adults with unipolar depression (OADEP).

METHODS

After excluding acutely ill patients, the executive functioning of OABD was compared to that of OADEP and healthy controls (n = 22, n = 20, n = 22; respectively). Cognitive insight, a sub-domain of executive functioning, was operationalized as the discrepancy between the participants' self-reported cognitive functioning and appraisals that were made by their care partners. To complement the cognitive profiling, the groups were compared in information processing speed, verbal memory, and visual-spatial memory.

RESULTS

OABD were impaired in several cognitive domains compared to healthy controls, most prominently in executive functioning and memory. OABD had poorer executive functioning and visual-spatial memory than OADEP. The findings also tentatively point toward intact cognitive insight among OABD, while OADEP seem to have a heightened level of awareness of their cognitive impairment.

CONCLUSIONS

OABD have a unique profile of cognitive impairment compared to OADEP. It is characterized by a more severe cognitive impairment, accompanied by relatively intact cognitive insight. The findings may help clarify the cognitive profile of OABD and assist in the development of cognitive rehabilitation programs tailored to their needs. They should, however, be considered preliminary and await further research.

Association of the CD2AP locus with cognitive functioning among middle-aged individuals with a family history of Alzheimer's disease

First-degree family history is an established risk factor for Alzheimer's disease (AD). We investigated the association of late-onset AD risk loci with cognitive functioning among 315 offspring of AD patients. Participants were cognitively normal Jewish individuals, aged 40-65 years, from the Israel Registry for Alzheimer's Prevention (IRAP) study. Twenty-two single-nucleotide polymorphisms (SNPs) within these loci and the APOE E4 allele were included in the final analyses, and a polygenic risk score was also calculated. Using linear regression (assuming an additive genetic model), we found a significant association only for SNP rs9473117, located near the CD2-associated protein (CD2AP) gene, with global cognition. Controlling for demographic variables (age, sex, years of education, and ancestry), the late-onset AD risk allele C was associated with lower global cognitive functioning (p = 0.0005), and withstood correction for multiple testing. After adjusting for additional characteristics (APOE E4 status and then also for cardiovascular factors), the results remained essentially unchanged (p = 0.0003 and p = 0.0005, respectively). In secondary analyses examining specific cognitive domains, rs9473117 was similarly associated with episodic memory (p = 0.005), language (p = 0.009), and working memory/attention (p = 0.018) but not with executive functions (p = 0.27). Again, the results were similar after adjusting for APOE E4 status and cardiovascular factors. The polygenic risk score was not associated with global cognitive functioning or with any of the 4 domains. In conclusion, our findings suggest a contribution of the CD2AP locus to cognitive functioning in middle-aged individuals with a parental history of AD. Further validations, including in longitudinal studies, are required.

Higher BMI is associated with smaller regional brain volume in older adults with type 2 diabetes

AIMS/HYPOTHESIS

There are established relationships between adiposity (obesity) and higher dementia risk, faster cognitive decline and associated neural injury. Type 2 diabetes is strongly linked to greater adiposity and has been consistently associated with neural injury and poor cognitive outcomes. However, although obesity is a major cause of type 2 diabetes, there is limited evidence on the association of adiposity with brain atrophy among individuals with type 2 diabetes.

METHODS

We examined the association of BMI (a measure of adiposity), and of long-term trajectories of BMI (three empirically identified groups of trajectories-'normal', 'overweight' and 'obese'-using SAS macro PROC TRAJ), with regional brain volume, in a sample of older individuals (aged 64-84) with type 2 diabetes participating in the Israel Diabetes and Cognitive Decline Study (n = 198).

RESULTS

Using linear regression, we found that greater BMI was associated with smaller volumes of the inferior frontal gyrus (IFG) (r = -0.25, p = 0.001) and the middle temporal gyrus (r = -0.19; p = 0.010) after adjusting for sociodemographic covariates and total intracranial volume. In addition, there were significant differences between BMI trajectory groups in IFG volume (F = 4.34, p = 0.014), such that a long-term trajectory of obesity was associated with a smaller volume. Additional adjustment for cardiovascular and diabetes-related potential confounders did not substantively alter the results. There were no associations of adiposity with superior frontal gyrus, middle frontal gyrus or total grey matter volumes.

CONCLUSIONS/INTERPRETATION

In older adults with type 2 diabetes, long-term adiposity may have a detrimental impact on volume of brain regions relevant to cognitive functioning. Further studies to identify the underlying mechanisms are warranted. Graphical abstract.

Long-term trajectories of BMI predict carotid stiffness and plaque volume in type 2 diabetes older adults: a cohort study

BACKGROUND

High body mass index (BMI) is a risk factor for type 2 diabetes and cardiovascular disease. However, its relationships with indices of carotid stiffness and plaque volume are unclear. We investigated associations of long-term measurements of BMI with indices of carotid stiffness and atherosclerosis among non-demented diabetes patients from the Israel Diabetes and Cognitive Decline (IDCD) study.

METHODS

Carotid ultrasound indices [carotid intima media thickness (cIMT), distensibility, elastography and plaque volume] were assessed in N = 471 participants. Mean BMI across all MHS diabetes registry measurements and trajectories of BMI were calculated. BMI was categorized into three trajectory groups representing: a relatively stable normal weight (n = 185, 44%), overweight trajectory (n = 188, 44.8%) and a trajectory of obesity (n = 47, 11.2%). Linear and logistic regressions estimated associations of carotid indices with mean BMI and BMI trajectories.

RESULTS

Compared to the normal weight trajectory, an obesity trajectory was associated with carotid distensibility (β = - 3.078, p = 0.037), cIMT (β = 0.095, p = 0.004), and carotid elastography (β = 0.181, p = 0.004) but not with plaque volume (β = 0.066, p = 0.858). Compared with the normal weight trajectory, an obesity trajectory was associated with increased odds for impaired carotid distensibility (OR = 2.790, p = 0.033), impaired cIMT (OR = 5.277, p = 0.001) and large carotid plaque volume (OR = 8.456, p = 0.013) but not with carotid elastography (OR = 1.956, p = 0.140). Mean BMI was linearly associated with Distensibility (β = - 0.275, p = 0.005) and cIMT (β = 0.005, p = 0.026).

CONCLUSIONS

Long-term measurements of adiposity are associated with indices of carotid stiffness and plaque volume among older type 2 diabetes adults.

C-reactive protein in midlife is associated with depressive symptoms two decades later among men with coronary heart disease

Aim: We investigated the relationship between midlife C-reactive protein (CRP) levels in men with coronary heart disease (CHD) and depressive symptoms at old age. CRP levels were measured in a subset of patients with CHD, who previously participated in a secondary prevention trial.Methods: Depressive symptoms were evaluated in survivors of the original cohort 15.0 ± 3 and 19.9 ± 1 years later (T1, n = 463 and T2, n = 314 respectively) using the Geriatric Depression Scale (GDS), 15-item version. Logistic regression was used to estimate ORs and 95%CIs for presence of potentially clinically significant depressive symptoms (GDS ≥5) at T1 and T2.Results: Adjusting for demographic and health-related variables, the OR (95%CI) for GDS ≥5 was 1.23 (0.65-2.33); p = .53 at T1 and 2.36 (1.16-4.83); p = .018 at T2 in the top CRP tertile compared to the others. Similarly, consistently high CRP levels in the top tertile at baseline and 2 years later, were associated with OR of 2.85 (95%CI 1.29-6.30); p = .01 for GDS ≥5 at T2.Conclusions: Presence and persistence of low-grade inflammation in men with CHD during midlife are associated with increased risk of depressive symptoms twenty years later. Among middle aged men with CHD, low-grade inflammation may provide an important added value for prediction of depression in old age.

Computerized Cognitive Training for Older Adults at Higher Dementia Risk due to Diabetes: Findings From a Randomized Controlled Trial

BACKGROUND

To evaluate the effects of adaptive and tailored computerized cognitive training on cognition and disease self-management in older adults with diabetes.

METHODS

This was a single-blind trial. Eighty-four community-dwelling older adults with diabetes were randomized into a tailored and adaptive computerized cognitive training or a generic, non-tailored or adaptive computerized cognitive training condition. Both groups trained for 8 weeks on the commercially available CogniFit program and were supported by a range of behavior change techniques. Participants in each condition were further randomized into a global or cognition-specific self-efficacy intervention, or to a no self-efficacy condition. The primary outcome was global cognition immediately following the intervention. Secondary outcomes included diabetes self-management, meta-memory, mood, and self-efficacy. Assessments were conducted at baseline, immediately after the training, and at a 6-month follow-up.

RESULTS

Adherence and retention were lower in the generic computerized cognitive training condition, but the self-efficacy intervention was not associated with adherence. Moderate improvements in performance on a global cognitive composite at the posttreatment assessments were observed in both cognitive training conditions, with further small improvement observed at the 6-month follow-up. Results for diabetes self-management showed a modest improvement on self-rated diabetes care for both intervention conditions following the treatment, which was maintained at the 6-month follow-up.

CONCLUSIONS

Our findings suggest that older adults at higher dementia risk due to diabetes can show improvements in both cognition and disease self-management following home-based multidomain computerized cognitive training. These findings also suggest that adaptive difficulty and individual task tailoring may not be critical components of such interventions.

TRIAL REGISTRATION

NCT02709629.

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.

Vitamin E Intake Is Associated with Lower Brain Volume in Haptoglobin 1-1 Elderly with Type 2 Diabetes

BACKGROUNDS

The efficacy of vitamin E in prevention of diabetes-related complications differs by Haptoglobin (Hp) genotype.

OBJECTIVE

To examine the role of Hp genotype in the relationship of vitamin E intake with brain volume in cognitively normal elderly patients with type 2 diabetes.

METHODS

Brain volumes for the superior, middle, and inferior frontal gyri and for the middle temporal gyrus were generated from structural T1 MRI in 181 study participants (Hp 1-1: n = 24, Hp 2-1: n = 77, Hp 2-2: n = 80). Daily vitamin E intake was assessed using the Food Frequency Questionnaire. Analyses of covariance, controlling for demographic and cardiovascular variables was used to evaluate whether the association of daily vitamin E intake with brain volume was modified by Hp genotype.

RESULTS

Average age was 70.8 (SD = 4.2) with 40% females, and mean Mini-Mental State Examination score of 28.17 (SD = 1.90). A significant interaction was found between vitamin E intake and Hp genotype in inferior frontal gyrus' volume; p = 0.0108. For every 1 microgram increase in vitamin E intake, the volume of the inferior frontal gyrus decreased by 0.955% for Hp 1-1 (p = 0.0348), increased by 0.429% for Hp 2-1 (p = 0.0457), and by 0.077% for Hp 2-2 (p = 0.6318). There were no significant interactions between vitamin E intake and Hp genotype for the middle (p = 0.6011) and superior (p = 0.2025) frontal gyri or for the middle temporal gyrus (p = 0.503).

CONCLUSIONS

The effect of dietary vitamin E on the brain may differ by Hp genotype. Studies examining the impact of vitamin E on brain-related outcomes should consider Hp genotype.

Differences in Semantic Memory Encoding Strategies in Young, Healthy Old and MCI Patients

Associative processes, such as the encoding of associations between words in a list, can enhance episodic memory performance and are thought to deteriorate with age. Here, we examine the nature of age-related deficits in the encoding of associations, by using a free recall paradigm with visual arrays of objects. Fifty-five participants (26 young students; 20 cognitive healthy older adults; nine patients with Mild Cognitive Impairment, MCI) were shown multiple slides (experimental trials), each containing an array of nine common objects for recall. Most of the arrays contained three objects from three semantic categories, each. In the remaining arrays, the nine objects were unrelated. Eye fixations were also monitored during the viewing of the arrays, in a subset of the participants. While for young participants the immediate recall was higher for the semantically related arrays, this effect was diminished in healthy elderly and totally absent in MCI patients. Furthermore, only in the young group did the sequence of eye fixations show a semantic scanning pattern during encoding, even when the related objects were non- adjacent in the array. Healthy elderly and MCI patients were not influenced by the semantic relatedness of items during the array encoding, to the same extent as young subjects, as observed by a lack of (or reduced) semantic scanning. The results support a version of the encoding of the association aging-deficit hypothesis.

TCF7L2 polymorphisms are associated with amygdalar volume in elderly individuals with Type 2 Diabetes

The association between several Single Nucleotide Polymorphisms (SNPs) within the transcription factor 7-like 2 (TCF7L2) gene and Type 2 Diabetes (T2D) as well as additional T2D-related traits is well established. Since alteration in total and regional brain volumes are consistent findings among T2D individuals, we studied the association of four T2D susceptibility SNPS within TCF7L2 (rs7901695, rs7903146, rs11196205, and rs12255372) with volumes of white matter hyperintensities (WMH), gray matter, and regional volumes of amygdala and hippocampus obtained from structural MRI among 191 T2D elderly Jewish individuals. Under recessive genetic model (controlling for age, sex and intracranial volume), we found that for all four SNPs, carriers of two copies of the T2D risk allele (homozygous genotype) had significantly smaller amygdalar volume: rs7901695- CC genotype vs. CT + TT genotypes, p = 0.002; rs7903146-TT vs. TC + CC, p = 0.003; rs11196205- CC vs. CG + GG, p = 0.0003; and rs12255372- TT vs. TG + GG, p = 0.003. Adjusting also for T2D-related covariates, body mass index (BMI), and ancestry did not change the results substantively (rs7901695, p = 0.003; rs7903146, p = 0.005; rs11196205, p = 0.001; and rs12255372, p = 0.005). Conditional analysis demonstrated that only rs11196205 was independently associated with amygdalar volume at a significant level. Separate analysis of left and right amygdala revealed stronger results for left amygdalar volume. Taken together, we report association of TCF7L2 SNPs with amygdalar volume among T2D elderly Jewish patients. Further studies in other populations are required to support these findings and reach more definitive conclusions.

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

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

The CADM2 gene is associated with processing speed performance - evidence among elderly with type 2 diabetes

Objectives: Recent large-scale meta-analysis of genome-wide association studies (GWAS) from multiple cohorts, demonstrated the association of the single nucleotide polymorphism (SNP) rs17518584, with processing speed (measured by the Digit Symbol Substitution Test (DSST) or the Letter Digit Substitution Test (LDST)), at GWAS significance level. This SNP is located within the cell adhesion molecule 2 (CADM2) gene. We aimed to validate this finding in our sample of 944 cognitively normal Jewish elderly individuals with type 2 diabetes (T2D), a population which is at risk for cognitive decline and dementia.Methods: Using linear regression, we studied the association of rs17518584 with DSST performance, adjusting for demographic, T2D-related characteristics and cardiovascular factors. In secondary analyses, associations with performance in four cognitive domains (episodic memory, language/semantic categorisation, attention/working memory and executive function) and overall cognition were examined.Results: Controlling for sex, age at cognitive assessment, years of education and ancestry, we found a significant association of rs17518584 with DSST performance (P = 0.013), consistent with the originally reported effect direction. Results remained significant even when the additional covariates (T2D-related and cardiovascular factors) were included in the analysis (P = 0.034). Moreover, this SNP was significantly associated with performance in the cognitive domains of language/semantic categorisation and executive function, as well as overall cognition.Conclusions: Taken together, irrespective of T2D-related characteristics and cardiovascular factors, our findings provide independent support for the association of CADM2 SNP rs17518584 with processing speed (and demonstrate association with additional cognitive phenotypes), among cognitively normal elderly individuals with T2D.

The associations between objective and subjective health among older adults with type 2 diabetes: The moderating role of personality

BACKGROUND

Objective and subjective health are two powerful constructs which predict morbidity and mortality across a range of conditions including Type 2 Diabetes (T2D). Studies, however, suggest that these two constructs do not necessarily correlate, as some people with poor objective health perceive their health as good, while other people with good objective health perceive their health as poor. We seek to examine the role of personality as a moderator of the associations between objective and subjective health among older adults with T2D, who are likely to experience poor objective and subjective health due to their chronic medical condition.

METHODS

Cross-sectional study of 368 individuals with T2D (72 ± 4 years, 42% women), participating in the Israel Diabetes and Cognitive Decline Study. Personality was conceptualized using the five-factor model (agreeableness, conscientiousness, extraversion, neuroticism, openness). Objective health was operationalized by T2D-related clinical status, cognitive function, and motor ability. Subjective health was assessed using a single self-report question. Hayes' process macro was used for the moderation analyses.

RESULTS

The objective-subjective health associations were stronger among individuals with increased neuroticism (proportion of days covered: p = 0.02; cognitive function: p = 0.003; hand grip: p = 0.02; 3-m walk: p = 0.04) as well as decreased openness (cognitive status: p = 0.04) and agreeableness (3-m walk: p = 0.02).

DISCUSSION

Personality traits, and specifically neuroticism, can modify the associations between objective and subjective health in older adults with T2D. Findings contribute to the understanding of health as a multidimensional construct that encompasses medical and psychological aspects, especially among older adults with a chronic illness.

The Association of Depressive Symptoms With Brain Volume Is Stronger Among Diabetic Elderly Carriers of the Haptoglobin 1-1 Genotype Compared to Non-carriers

Aim: Depression is highly prevalent in type 2 diabetes and is associated with lower adherence to medical treatments, worse glycemic control, and increased risk for diabetes-related complications. The mechanisms underlying depression in type 2 diabetes are unclear. The haptoglobin (Hp) genotype is associated with type 2 diabetes related complications including increased risk for cerebrovascular pathology and worse cognitive performance. Its relationship with depression is unknown. We investigated the role of Hp genotype on the association of depression with brain and white matter hyperintensities (WMH) volumes. Methods: Depressive symptoms (measured with the 15-item Geriatric Depression Scale), brain MRI, and Hp genotypes, were examined in elderly subjects with type 2 diabetes [29 (13.8%) Hp 1-1 carriers and 181 (86.2%) non-carriers]. The interaction of Hp genotype with number of depressive symptoms on regional brain measures was assessed using regression analyses. Results: The significant interactions were such that in Hp 1-1 carriers but not in non-carriers, number of depressive symptoms was associated with overall frontal cortex (p = 0.01) and WMH (p = 0.04) volumes but not with middle temporal gyrus volume (p = 0.43). Conclusions: These results suggest that subjects with type 2 diabetes carrying the Hp 1-1 genotype may have higher susceptibility to depression in the context of white matter damage and frontal lobe atrophy. The mechanisms underlying depression in diabetes may differ by Hp genotype.

Association of the Haptoglobin Gene Polymorphism With Cognitive Function and Decline in Elderly African American Adults With Type 2 Diabetes: Findings From the Action to Control Cardiovascular Risk in Diabetes-Memory in Diabetes (ACCORD-MIND) Study

IMPORTANCE

African American individuals have higher dementia risk than individuals of white race/ethnicity. They also have higher rates of type 2 diabetes, which may contribute to this elevated risk. This study examined the association of the following 2 classes of alleles at the haptoglobin (Hp) locus that are associated with poor cognition, cardiovascular disease, and mortality: Hp 1-1 (associated with poor cognition and cerebrovascular disease) and Hp 2-1 and Hp 2-2 (associated with greater risk of myocardial infarction and mortality). An additional polymorphism in the promoter region of the Hp 2 allele, restricted to individuals of African descent, yields a fourth genotype, Hp 2-1m. African American adults have a higher prevalence of Hp 1-1 (approximately 30%) compared with individuals of white race/ethnicity (approximately 14%), but the potential role of the Hp genotype in cognition among elderly African American individuals with type 2 diabetes is unknown.

OBJECTIVE

To assess the association of the Hp genotypes with cognitive function and decline in elderly African American adults with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used publicly available data and specimens from the Action to Control Cardiovascular Risk in Diabetes-Memory in Diabetes (ACCORD-MIND) study to investigate the association of the Hp genotypes with cognitive function and decline in 466 elderly African American participants with type 2 diabetes. The hypothesis was that the Hp 1-1 genotype compared with the other genotypes would be associated with more cognitive impairment and faster cognitive decline in elderly African American adults with type 2 diabetes. The initial ACCORD trial was performed from October 28, 1999, to September 15, 2014. This was a multicenter clinical study performed in an academic setting.

EXPOSURES

The Hp genotypes were determined from serum samples by polyacrylamide gel electrophoresis and by enzyme-linked immunosorbent assay.

MAIN OUTCOMES AND MEASURES

The Mini-Mental State Examination (MMSE) was used to measure cognitive function and change after 40 months. The MMSE score ranges from 0 to 30 points; higher scores represent better cognition. Associations were examined with analysis of covariance and linear regression, adjusting for age, sex, education, baseline glycated hemoglobin level, systolic blood pressure, diastolic blood pressure, cholesterol level, creatinine level, and treatment arm (intensive vs standard). The cognitive change model adjusted also for the baseline MMSE score.

RESULTS

Among 466 African American study participants (mean [SD] age, 62.3 [5.7] years), 64.8% were women, and the genotype prevalences were 29.4% (n = 137) for Hp 1-1, 36.1% (n = 168) for Hp 2-1, 10.9% (n = 51) for Hp 2-1m, and 23.6% (n = 110) for Hp 2-2. The groups differed in their baseline MMSE scores (P = .006): Hp 1-1 had the lowest MMSE score (mean [SE], 25.68 [0.23]), and Hp 2-1m had the highest MMSE score (mean [SE], 27.15 [0.36]). Using the least squares method, the 40-month decline was significant for Hp 1-1 (mean [SE], -0.41 [0.19]; P = .04) and for Hp 2-2 (mean [SE], -0.68 [0.21]; P = .001). However, the overall comparison across the 4 groups did not reach statistical significance for the fully adjusted model. The interaction of age with the Hp 1-1 genotype on MMSE score decline estimate per year change was significant (mean [SE], -0.87 [0.37]; P = .005), whereas it was not significant for Hp 2-1 (mean [SE], 0.06 [0.37]; P = .85), Hp 2-1m (mean [SE], -0.06 [0.51]; P = .89), and Hp 2-2 (mean [SE], -0.44 [0.41]; P = .29), indicating that cognitive decline in Hp 1-1 carriers was accentuated in older ages, whereas it was not significant for the other Hp genotypes.

CONCLUSIONS AND RELEVANCE

In this study, the Hp 1-1 genotype, which is 2-fold (approximately 30%) more prevalent among African American individuals than among individuals of white race/ethnicity, was associated with poorer cognitive function and greater cognitive decline than the other Hp genotypes. The Hp gene polymorphism may explain the elevated dementia risk in African American adults. The neuropathological substrates and mechanisms for these associations merit further investigation.

Depressive Symptoms Are Associated with Cognitive Function in the Elderly with Type 2 Diabetes

BACKGROUND

Type 2 diabetes (T2D) is a metabolic condition associated with poor clinical and cognitive outcomes including vascular disease, depressive symptoms, cognitive impairment, and dementia. In the general elderly population, depression has been consistently identified as a risk factor for cognitive impairment/decline. However, the association between depression and cognitive function in T2D has been understudied.

OBJECTIVE

We investigated the association between depression and cognitive function in a large sample of cognitively normal elderly with T2D.

METHODS

In this cross-sectional study, we examined 738 participants, aged 65-88 years old, enrolled in the Israel Diabetes and Cognitive Decline study. For each cognitive domain (Episodic Memory, Executive Function, Attention/Working Memory, Language/Semantic Categorization) and Overall Cognition, multiple linear regressions assessed its association with depression (score greater than 5 on the 15-item version of the Geriatric Depression Scale [GDS]), adjusting for age, sex, and education.

RESULTS

Depression (n = 66, 8.9%) was associated with worse performance on tasks of Executive Function (p = 0.004), Language/Semantic Categorization (p < 0.001), and Overall Cognition (p < 0.002), but not Episodic Memory (p = 0.643) or Attention/Working Memory (p = 0.488). Secondary analyses using GDS as a continuous variable did not substantially change the results. Adjusting also for a history of antidepressant medication use slightly weakened the findings.

CONCLUSION

Significant associations of depression with several cognitive domains and Overall Cognition even in cognitively normal elderly with T2D, suggest that depression may have a role in impaired cognitive function in T2D, which may be attenuated by antidepressants.

Computerized cognitive training for older diabetic adults at risk of dementia: Study protocol for a randomized controlled trial

Introduction

Older adults with type 2 diabetes are at high risk of cognitive decline and dementia and form an important target group for dementia risk reduction studies. Despite evidence that computerized cognitive training (CCT) may benefit cognitive performance in cognitively healthy older adults and those with mild cognitive impairment, whether CCT may benefit cognitive performance or improve disease self-management in older diabetic adults has not been studied to date. In addition, whether adaptive difficulty levels and tailoring of interventions to individuals' cognitive profile are superior to generic training remains to be established.

Methods

Ninety community-dwelling older (age ≥ 65) diabetic adults are recruited and randomized into a tailored and adaptive computerized cognitive training condition or to a generic, nontailored, or adaptive CCT condition. Both groups complete an 8-week training program using the commercially available CogniFit program. The intervention is augmented by a range of behavior-change techniques, and participants in each condition are further randomized into a global or cognition-specific phone-based self-efficacy (SE) condition, or a no-SE condition. The primary outcome is global cognitive performance immediately after the intervention. Secondary outcomes include diabetes self-management, meta-memory, mood, and SE.

Discussion

This pilot study is the first trial evaluating the potential benefits of home-based tailored and adaptive CCT in relation to cognitive and disease self-management in older diabetic adults. Methodological strengths of this trial include the double-blind design, the clear identification of the proposed active ingredients of the intervention, and the use of evidence-based behavior-change techniques. Results from this study will indicate whether CCT has the potential to lower the risk of diabetes-related cognitive decline. The outcomes of the trial will also advance our understanding of essential intervention parameters required to improve or maintain cognitive function and enhance disease self-management in this at-risk group.

Haptoglobin 1-1 Genotype Modulates the Association of Glycemic Control With Hippocampal Volume in Elderly Individuals With Type 2 Diabetes

Recent evidence suggests that glycemic control is associated with cognitive function in older patients with type 2 diabetes who are carriers of the haptoglobin (Hp) 1-1 genotype compared with noncarriers. We assessed whether poor glycemic control in Hp 1-1 carriers is more strongly associated with smaller hippocampal volume than in noncarriers. Hippocampal volume was generated from high-resolution structural T1 MRI obtained for 224 participants (28 Hp 1-1 carriers [12.5%] and 196 noncarriers [87.5%]) from the Israel Diabetes and Cognitive Decline (IDCD) study, who had a mean (SD) number of years in the Maccabi Healthcare Services (MHS) registry of 8.35 (2.63) and a mean (SD) HbA_1c level of 6.66 (0.73)% [49 mmol/mol]. A stronger negative association between right hippocampal volume and HbA_1c was found in patients with the Hp 1-1 genotype, with a 0.032-mL decrease in right hippocampal volume per 14% increase in HbA_1c (P = 0.0007) versus a 0.009-mL decrease in Hp 1-1 noncarriers (P = 0.047), after adjusting for total intracranial volume, age, sex, follow-up years in the registry, and cardiovascular factor (interaction, P = 0.025). This indicates that 29.66% of the total variance in right hippocampal volume is explained by HbA_1c levels among Hp 1-1 carriers and that 3.22% is explained by HbA_1c levels among Hp 1-1 noncarriers. Our results suggest that the hippocampus of Hp 1-1 carriers may be more vulnerable to the insults of poor glycemic control.

Hemoglobin A1c Variability Predicts Symptoms of Depression in Elderly Individuals With Type 2 Diabetes

OBJECTIVE

This study aimed to analyze the relationship of variability in hemoglobin A_1c (HbA_1c) over years with subsequent depressive symptoms.

RESEARCH DESIGN AND METHODS

Subjects (n = 837) were participants of the Israel Diabetes and Cognitive Decline (IDCD) study, which aimed to examine the relationship of characteristics of long-term type 2 diabetes with cognitive decline. All pertain to a diabetes registry established in 1998, which contains an average of 18 HbA_1c measurements per subject. The results presented here are based on the IDCD baseline examination. Symptoms of depression were assessed using the 15-item version of the Geriatric Depression Scale (GDS). To quantify the association between variability in glycemic control (measured as the SD of HbA_1c measurements [HbA_1c-SD]) since 1998 with the number of depression symptoms at IDCD baseline, incidence rate ratios (IRRs) and corresponding 95% CIs were estimated via negative binomial regression modeling and used to account for the overdispersion in GDS scores.

RESULTS

Subjects' ages averaged 72.74 years (SD 4.63 years), and the mean number of years in the diabetes registry was 8.7 (SD 2.64 years). The mean GDS score was 2.16 (SD 2.26); 10% of subjects had a GDS score ≥6, the cutoff for clinically significant depression. Mean HbA_1c significantly correlated with HbA_1c-SD (r = 0.6625; P < 0.0001). The SD, but not the mean, of HbA_1c measurements was significantly associated with the number of subsequent depressive symptoms. For each additional 1% increase in HbA_1c-SD, the number of depressive symptoms increased by a factor of 1.31 (IRR = 1.31 [95% CI 1.03-1.67]; P = 0.03).

CONCLUSIONS

Variability in glycemic control is associated with more depressive symptoms.

Triceps and Subscapular Skinfold in Men Aged 40-65 and Dementia Prevalence 36 Years Later

BACKGROUND

The relationship of obesity with risk for dementia is complex and may change with age.

OBJECTIVE

To analyze the relationship between measures of obesity at age 40-65 and dementia prevalence in survivors 36 years later.

METHODS

Obesity-related measures of triceps and subscapular skinfold thickness were assessed in 1963 in n = 9,760 men aged 40-65 participating in the Israel Ischemic Heart Disease study. Cognitive evaluation and assessment of dementia prevalence were performed in n = 1,643 participants of the original cohort who survived until 1999/2000 (age ≥76 years) and had anthropometric measures in 1963.

RESULTS

Age-adjusted prevalence of dementia in survivors in 1999/2000 by baseline triceps skinfold quintile was 20.5%, 21.2%, 17.6%, 15.6%, and 14.5%, respectively, from lowest to highest (p = 0.006 in trend test). Using logistic regression, a 6-mm increment of triceps skinfold was associated with an age and BMI-adjusted odds ratio of 0.81 (95% CI, 0.70-0.94) for dementia prevalence among survivors. Age-adjusted risk for dementia by subscapular skinfold quintile demonstrated 20.5%, 17.1%, 15.7%, 19.4%, and 18.1%, respectively, in groups of subjects by subscapular skinfold quintile from lowest to highest (p = 0.6 in trend test).

CONCLUSIONS

Lower triceps skinfold at age 40-65, reflecting diminished peripheral fat, was associated with higher dementia prevalence in late life, potentially suggesting a protective role of peripheral fat to brain health.