Search

Introduction: Although poor glycemic control is associated with dementia, it is unknown if variability in glycemic control, even in those with optimal glycosylated hemoglobin A 1c (HbA 1c ) levels, increases dementia risk., Methods: Among 171,964 people with type 2 diabetes, we evaluated the hazard of dementia association with long-term HbA 1c variability using five operationalizations, including standard deviation (SD), adjusting for demographics and comorbidities., Results: The mean baseline age was 61 years (48% women). Greater HbA 1c SD was associated with greater dementia hazard (adjusted hazard ratio = 1.15 [95% confidence interval: 1.12, 1.17]). In stratified analyses, higher HbA 1c SD quintiles were associated with greater dementia hazard among those with a mean HbA 1c  < 6% (P = 0.0004) or 6% to 8% (P < 0.0001) but not among those with mean HbA 1c ≥ 8% (P = 0.42)., Discussion: Greater HbA 1c variability is associated with greater dementia risk, even among those with HbA 1c concentrations at ideal clinical targets. These findings add to the importance and clinical impact of recommendations to minimize glycemic variability., Highlights: We observed a cohort of 171,964 people with type 2 diabetes (mean age 61 years). This cohort was based in Northern California between 1996 and 2018. We examined the association between glycosylated hemoglobin A 1c (HbA 1c ) variability and dementia risk. Greater HbA 1c variability was associated with greater dementia hazard. This was most evident among those with normal-low mean HbA 1c concentrations., (© 2024 The Author(s). Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

Importance: The levels of glycemic control associated with the lowest risk of dementia in people with type 2 diabetes are unknown. This knowledge is critical to inform patient-centered glycemic target setting., Objective: To examine the associations between cumulative exposure to various ranges of glycated hemoglobin (HbA1c) concentrations with dementia risk across sex and racial and ethnic groups and the association of current therapeutic glycemic targets with dementia risk., Design, Setting, and Participants: This cohort study included members of the Kaiser Permanente Northern California integrated health care system with type 2 diabetes who were aged 50 years or older during the study period from January 1, 1996, to September 30, 2015. Individuals with fewer than 2 HbA1c measurements during the study period, prevalent dementia at baseline, or less than 3 years of follow-up were excluded. Data were analyzed from February 2020 to January 2023., Exposures: Time-updated cumulative exposure to HbA1c thresholds. At each HbA1c measurement, participants were categorized based on the percentage of their HbA1c measurements that fell into the following categories: less than 6%, 6% to less than 7%, 7% to less than 8%, 8% to less than 9%, 9% to less than 10%, and 10% or more of total hemoglobin (to convert percentage of total hemoglobin to proportion of total hemoglobin, multiply by 0.01)., Main Outcomes and Measures: Dementia diagnosis was identified using International Classification of Diseases, Ninth Revision codes from inpatient and outpatient encounters. Cox proportional hazards regression models estimated the association of time-varying cumulative glycemic exposure with dementia, adjusting for age, race and ethnicity, baseline health conditions, and number of HbA1c measurements., Results: A total of 253 211 participants were included. The mean (SD) age of participants was 61.5 (9.4) years, and 53.1% were men. The mean (SD) duration of follow-up was 5.9 (4.5) years. Participants with more than 50% of HbA1c measurements at 9% to less than 10% or 10% or more had greater risk of dementia compared with those who had 50% or less of measurements in those categories (HbA1c 9% to <10%: adjusted hazard ratio [aHR], 1.31 [95% CI, 1.15-1.51]; HbA1c≥10%: aHR, 1.74 [95% CI, 1.62-1.86]). By contrast, participants with more than 50% of HbA1c concentrations less than 6%, 6% to less than 7%, or 7% to less than 8% had lower risk of dementia (HbA1c<6%: aHR, 0.92 [95% CI, 0.88-0.97]; HbA1c 6% to <7%: aHR, 0.79 [95% CI, 0.77-0.81]; HbA1c 7% to <8%: aHR, 0.93 [95% CI, 0.89-0.97])., Conclusions and Relevance: In this study dementia risk was greatest among adults with cumulative HbA1c concentrations of 9% or more. These results support currently recommended relaxed glycemic targets for older people with type 2 diabetes.

Background and Objectives: Volunteer-delivered programs to assist people with dementia and/or delirium in-hospital can provide person-centered one-on-one support in addition to usual care. These programs could mitigate hospital resource demands; however, their effectiveness is unknown. This review evaluated literature of volunteer programs in acute hospital settings for people living with dementia and/or delirium., Research Design and Methods: Four databases were searched. Studies that reported patient or program outcomes were included (i.e., delirium incidence, length of stay, number of falls, satisfaction). Risk of bias was completed. Meta-analysis was performed where 2 or more studies measured the same outcome. Narrative synthesis was performed on the qualitative results., Results: Eleven studies were included in the review, with varied design, participant groups and outcomes measured. Risk of bias averaged 71%. Volunteer-delivered programs addressed delirium risk factors, for example, hydration/nutrition, mobility, use of sensory aids. Eight patients and 6 program outcomes were captured, but only 3 patient outcomes could be pooled. Meta-analyses demonstrated a reduction in delirium incidence (rate ratio = 0.65; 95% confidence interval [CI] 0.47, 0.90) but no reduction in length of stay (mean difference -1.09; 95% CI -0.58, 2.77) or number of falls (rate ratio = 0.67; 95% CI 0.19, 2.35). Narrative synthesis identified benefits to patients (e.g., less loneliness), volunteers (sense of meaning), and staff (timesaving, safety)., Discussion and Implications: Volunteer-delivered programs for inpatients with dementia and/or delirium may provide benefits for patients, volunteers, and staff. However, studies conducted with more robust designs are required to determine overall effectiveness on program outcomes. Further high-quality research appropriate for this vulnerable population is required to identify volunteer program effectiveness., (© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objectives: Age and female sex are risk factors for dementia, and menopause is associated with cognitive dysfunction. Previous work largely considered the effects of sex and menopause as being independent of age. We studied whether age interacts with sex or menopause in explaining imaging biomarkers of dementia during midlife., Methods: In this cross-sectional study of UK Biobank participants with brain magnetic resonance imaging (MRI), we explored the interaction of age with sex or menopausal status in explaining total brain volume (TBV), gray matter volume (GMV), white matter volume (WMV), white matter hyperintensity volume (WMHV), regional cortical volume , and subcortical volume., Results: Data were available for 1827 postmenopausal women, 230 pre/perimenopausal women and 2165 men (median age 63.3 years). There was a significant interaction between age and sex (P = .024) for TBV, where the inverse association age with TBV was steeper in women (β = -5.35 mL/year) than in men (β = -4.77 mL/year). Similar age-sex interactions were also observed for GMV and WMV. In women, there was a significant interaction between age and menopausal status (P = .007) where the inverse association of age with TBV was steeper in postmenopausal (β = -5.89 mL/year) than in pre/perimenopausal women (β = -1.61 mL/year). Similar age-menopause interactions were found in predicting lower GMV and higher WMHV. Differences in the direction of these age-sex and age-menopause interactions were found for regional cortical and subcortical brain volumes., Conclusion: Sex and menopause both interact with age during midlife in explaining MRI biomarkers of dementia. Further work is required to understand the mechanisms driving these interactions to develop strategies for delaying dementia., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background and Objectives: Older adults with cognitive impairment are vulnerable to frequent hospital admissions and emergency department presentations. The aim of this study was to use a codesign approach to develop MyCare Ageing, a programme that will train volunteers to provide psychosocial support to older people with dementia and/or delirium in hospital and at home when discharged from hospital., Setting: Melbourne, Victoria, Australia., Research Design: This study adopts an action research methodology. We report on two co-design workshops with keystakeholders: Workshop 1: identification of components from three existing programmes to inform the development of the MyCare Ageing program logic and, Workshop 2: identification of implementation strategies., Participants: The key stakeholders and workshop participants included clinicians (geriatricians, nurses and allied health), hospital staff (volunteer coordinators and hospital executives), Baptcare staff, a consumer, researchers and implementation experts and project staff., Results: Workshop 1 identified the components from three existing programmes-the Volunteer Dementia and Delirium Care programme, Home-Start and MyCare for inclusion in MyCare Ageing. In workshop 2, the p implementation plan was developed taking into consideration hospital-specific processes, training and support needs of volunteers and safety and risk management processes., Discussion and Conclusion: The codesign process was successfully applied to develop the MyCare Ageing programme to provide volunteer support to patients with dementia and/or delirium in hospital and their transition home. MyCare Ageing is an innovative programme that meets an identified need from hospitals and consumers to support patients with dementia and/or delirium to improve psychosocial outcomes on discharge from hospital., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To explore the perceived acceptability of the Volunteer Dementia and Delirium Care (VDDC)© program components from the perspective of key stakeholders in a metropolitan health network., Methods: A mixed-methods design was used. Surveys (nurses) and focus groups and interviews (hospital staff, volunteers, patients and caregivers) were conducted simultaneously. Descriptive statistics were used to profile the survey responses. The framework method was used to analyse the qualitative data., Results: The majority of nurses identified that it is acceptable for volunteers to read to, and converse and play games with patients. Hospital staff perceived risk in volunteers assisting with feeding and mobilisation. Overall participants believed the VDDC was acceptable and would be of benefit to the patients., Conclusion: Key stakeholders have a favourable view of the VDDC© program. Strategies can be developed to address the identified issues, and components of the program may be amended to ensure that implementation is acceptable., (© 2019 AJA Inc.)

Objective: To explore the perceived barriers and enablers to the implementation of the Volunteer Dementia and Delirium © program from the perspective of key stakeholders in a metropolitan hospital network., Methods: Focus groups and interviews with hospital staff, volunteers, patients and caregivers. Deductive analysis was conducted for the Behaviour Change Wheel (COM-B) domains, and inductive thematic analysis for emerging themes., Results: Utilising the skills and knowledge of volunteers, making the program available to all patients, and recognising that volunteers will improve the care experience for patients were identified as enablers. Threats to volunteer safety, difficulty in defining roles and responsibilities of volunteers, volunteer attrition and availability and supervision of volunteers were perceived as barriers to implementation., Conclusion: To enhance the implementation of the program into a metropolitan setting, strategies addressing the identified barriers and enablers need to be developed., (© 2019 AJA Inc.)

Purpose of Review: Type 2 diabetes (T2D) is a well-established risk factor for the development of dementia. Dementia and T2D share some underlying pathophysiology that has led to interest in the potential to repurpose drugs used in the management of T2D to benefit brain health. This review describes the scientific data available on the use of T2D medications for the risk reduction or management of dementia, in people with and without T2D., Recent Findings: Results from basic laboratory research support the potential for commonly-used medications for T2D, including those with direct glucose-lowering properties, to have a beneficial effect on brain health. However, human studies have been mostly observational in nature and report conflicting results. Preliminary data suggest that intranasal insulin, metformin, and GLP-1 agonists show promise for dementia, but confirmatory evidence for their benefit in dementia is still lacking. Current evidence does not support the repurposing of T2D medications for dementia risk reduction or management. Research in the field of T2D and dementia is active, and further data are required before definitive conclusions can be drawn.

INTRODUCTION: Although poor glycemic control is associated with dementia, it is unknown if variability in glycemic control, even in those with optimal glycosylated hemoglobin A1c (HbA1c) levels, increases dementia risk. METHODS: Among 171,964 people with type 2 diabetes, we evaluated the hazard of dementia association with long-term HbA1c variability using five operationalizations, including standard deviation (SD), adjusting for demographics and comorbidities. RESULTS: The mean baseline age was 61 years (48% women). Greater HbA1c SD was associated with greater dementia hazard (adjusted hazard ratio = 1.15 [95% confidence interval: 1.12, 1.17]). In stratified analyses, higher HbA1c SD quintiles were associated with greater dementia hazard among those with a mean HbA1c

IntroductionWomen comprise two-thirds of people with dementia, making female sex a significant dementia risk factor. Both type 1 diabetes (T1D) and type 2 diabetes (T2D) are known dementia risk factors with an increasing global incidence. Understanding whether subtle sex differences persist in cognitive function prior to dementia in the context of diabetes may help elucidate the magnitude of sex effects on dementia risk.Research design and methodsWe examined cross-sectional data from the Study of Longevity in Diabetes (SOLID), a prospective cohort study of members of Kaiser Permanente Northern California aged 60 years and older with T1D (n=758), T2D (n=232) and without either T1D or T2D (n=247). We used factor analysis to generate summary scores of cognitive domains and used regression analyses to examine the associations between sex and cognition adjusting for sociodemographic and cardiovascular confounders.ResultsWe included 1237 participants (630 women and 607 men) with mean age 68 years. By design, the distribution of men and women in T1D, T2D and no diabetes was similar. Women had better cognitive performance than men in global cognition (β=0.21, 95% CI 0.16 to 0.26), language (β=0.08, 95% CI 0.004 to 0.15), executive function (β=0.13, 95% CI 0.05 to 0.20), episodic verbal memory (β=0.68, 95% CI 0.59 to 0.77) and attention (β=0.20, 95% CI 0.11 to 0.28) but not in episodic visual memory (β=0.006, 95% CI -0.07 to 0.09) adjusting for age and education independent of diabetes status. We did not find an interaction between sex and diabetes status for any of the cognitive outcomes.ConclusionsWomen in late mid-life have better cognitive performance than men in many cognitive domains independent of the presence of T1D or T2D. Further work is required to understand whether these differences change over time or in older cohorts and to understand their relationship to subsequent dementia.

ObjectiveTo study longitudinal relationships between type 2 diabetes mellitus (T2DM), cortical thickness, and cognitive function in older people with normal cognition, mild cognitive impairment, and Alzheimer disease (AD).MethodsThe sample was derived from the Alzheimer's Disease Neuroimaging Initiative cohort who underwent brain MRI and cognitive tests annually for 5 years. Presence of T2DM was based on fasting blood glucose ≥7.0mml/L or the use of glucose-lowering agents. We used latent growth curve modeling to explore longitudinal relationships between T2DM, cortical thickness, and cognitive function, adjusting for relevant covariates and testing for interactions.ResultsThere were 124 people with T2DM (mean age 75.5 years, SD 6.2) and 693 without T2DM (mean age 75.1 years, SD 6.9) with at least 1 MRI available. AD and lower cortical thickness at study entry was associated with a lower chance of having a MRI available at each follow-up phase (all p < 0.001). T2DM was associated with lower baseline cortical thickness (p = 0.01). We found no direct effect of T2DM on decline in cortical thickness or cognitive function, but there was an indirect pathway linking T2DM and cognitive decline via baseline cortical thickness (β = -0.17, p = 0.022). There was an interaction between T2DM and education whereby the negative effect of T2DM on baseline cortical thickness was reduced in those with greater education (β = 0.34, p = 0.037). These associations changed minimally when adjusted for baseline cognitive diagnosis.ConclusionsIn an older cohort with low cerebrovascular disease burden, T2DM contributes to cognitive decline via neurodegeneration. Prior brain and cognitive reserve may protect against this effect.

INTRODUCTION: Although poor glycemic control is associated with dementia, it is unknown if variability in glycemic control, even in those with optimal glycosylated hemoglobin A1c (HbA1c) levels, increases dementia risk. METHODS: Among 171,964 people with type 2 diabetes, we evaluated the hazard of dementia association with long‐term HbA1c variability using five operationalizations, including standard deviation (SD), adjusting for demographics and comorbidities. RESULTS: The mean baseline age was 61 years (48% women). Greater HbA1c SD was associated with greater dementia hazard (adjusted hazard ratio = 1.15 [95% confidence interval: 1.12, 1.17]). In stratified analyses, higher HbA1c SD quintiles were associated with greater dementia hazard among those with a mean HbA1c < 6% (P = 0.0004) or 6% to 8% (P < 0.0001) but not among those with mean HbA1c ≥ 8% (P = 0.42). DISCUSSION: Greater HbA1c variability is associated with greater dementia risk, even among those with HbA1c concentrations at ideal clinical targets. These findings add to the importance and clinical impact of recommendations to minimize glycemic variability. Highlights: We observed a cohort of 171,964 people with type 2 diabetes (mean age 61 years).This cohort was based in Northern California between 1996 and 2018.We examined the association between glycosylated hemoglobin A1c (HbA1c) variability and dementia risk.Greater HbA1c variability was associated with greater dementia hazard.This was most evident among those with normal–low mean HbA1c concentrations. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes (T2D) is associated with an increased risk of dementia and early features may become evident even in mid-life. Characterizing these early features comprehensively requires multiple measurement modalities and careful selection of participants with and without T2D. Objective: We conducted a cross-sectional multimodal imaging study of T2D-discordant twins in late mid-life to provide insights into underlying mechanisms. Methods: Measurements included computerized cognitive battery, brain MRI (including arterial spin labelling, diffusion tensor, resting state functional), fluorodeoxyglucose (FDG)-PET, and retinal optical coherence tomography. Results: There were 23 pairs, mean age 63.7 (±6.1) years. In global analyses, T2D was associated with poorer attention (β= –0.45, p <0.001) and with reduced FDG uptake (β= –5.04, p = 0.02), but not with cortical thickness (p = 0.71), total brain volume (p = 0.51), fractional anisotropy (p = 0.15), mean diffusivity (p = 0.34), or resting state activity (p = 0.4). Higher FDG uptake was associated with better attention (β= 3.19, p = 0.01) but not with other cognitive domains. In regional analyses, T2D was associated with lower accumbens volume (β= –44, p = 0.0004) which was in turn associated with poorer attention. Conclusion: T2D-related brain dysfunction in mid-life manifests as attentional loss accompanied by evidence of subtle neurodegeneration and global reduction in cerebral metabolism, in the absence of overt cerebrovascular disease. [ABSTRACT FROM AUTHOR]

The prevalence of type 2 diabetes (T2D) and cognitive dysfunction increases with age. As society ages, clinicians will be increasingly tasked with managing older people who have both T2D and cognitive dysfunction. T2D is associated with an increased risk of cognitive dysfunction and hence there is increasing interest in whether T2D is a causal factor in the pathogenesis of cognitive decline and dementia. Recent advances in the use of sensitive measures of in vivo brain dysfunction in life-course studies can help understand potential mechanistic pathways and also help guide recommendations for clinical practice. In this article we will describe new horizons in the understanding of cognitive dysfunction associated with T2D. Coming from a clinical perspective, we discuss potential mechanisms and pathways linking the 2 conditions and the contribution of multimodal neuroimaging and study designs to advancing understanding in the field. We also highlight the important issues on the horizon that will need addressing in clinical identification, management, and risk reduction for people with coexistent T2D and cognitive dysfunction. [ABSTRACT FROM AUTHOR]

Background: Physical inactivity is a risk factor for type 2 diabetes (T2D) and dementia. However, it is unknown if physical activity (PA) intensity is associated with brain health in people with T2D. Therefore, this study aimed to determine (i) associations between PA intensity and step count with both cognition and brain structure and (ii) if apolipoprotein E-ε4 or insulin therapy modifies any associations.Methods: Participants were people with T2D (n = 220; aged 55-86 years). An accelerometer worn over the right hip was used to obtain step count and moderate-to-vigorous PA (MVPA) averaged over 7 days. Cognition in 7 domains was obtained using a battery of neuropsychological tests. Brain structure was measured by Magnetic Resonance Imaging. Linear regression models were used to examine associations between step count, MVPA and each cognitive and Magnetic Resonance Imaging measure. Apolipoprotein E-ε4 × PA and insulin therapy × PA product terms were added to the models to examine effect modification.Results: The mean age of participants was 67.9 (SD = 6.3). Higher step count was associated with greater hippocampal volume (β = 0.028, 95% CI = 0.005, 0.051). Insulin therapy modified the association between MVPA and attention-processing speed, such that associations were significant in people receiving insulin therapy (p for interaction = .019). There were no other significant associations.Conclusions: Higher step count and greater time spent in MVPA may be associated with better hippocampal volume and attention-processing speed, respectively, in people with T2D. People with greater diabetes severity (receiving insulin therapy) may get more cognitive benefit from MVPA. [ABSTRACT FROM AUTHOR]

Objective: To explore the perceived barriers and enablers to the implementation of the Volunteer Dementia and Delirium© program from the perspective of key stakeholders in a metropolitan hospital network. Methods: Focus groups and interviews with hospital staff, volunteers, patients and caregivers. Deductive analysis was conducted for the Behaviour Change Wheel (COM‐B) domains, and inductive thematic analysis for emerging themes. Results: Utilising the skills and knowledge of volunteers, making the program available to all patients, and recognising that volunteers will improve the care experience for patients were identified as enablers. Threats to volunteer safety, difficulty in defining roles and responsibilities of volunteers, volunteer attrition and availability and supervision of volunteers were perceived as barriers to implementation. Conclusion: To enhance the implementation of the program into a metropolitan setting, strategies addressing the identified barriers and enablers need to be developed. [ABSTRACT FROM AUTHOR]

Background: Cognitive dysfunction is common in older adults, particularly in those with type 2 diabetes (T2D). Higher adherence to the Dietary Guidelines for Americans is associated with better brain health. However, it is unclear if adherence to the Australian Dietary Guidelines (ADG) is associated with cognition or brain structure in older adults.Objective: The aims of this study were to 1) examine the relation between adherence to the ADG, cognition, and brain MRI and 2) determine whether T2D modifies any associations.Methods: The Cognition and Diabetes in Older Tasmanians Study is a cross-sectional study in 688 people (n = 343 with T2D) aged 55-90 y. A validated 80-item food-frequency questionnaire was used to assess dietary intake. Adherence to the 2013 ADG was estimated using the Dietary Guidelines Index (DGI). Cognitive function in multiple domains was assessed with a comprehensive battery of neuropsychological tests and brain structure with MRI. Multivariable linear models were used to assess the associations between DGI, cognitive z scores, and brain structure. Effect modification for T2D was examined with a DGI × T2D product term.Results: The mean age of the sample was 69.9 y (SD: 7.4 y), with 57.1% men. The mean DGI was 54.8 (SD: 10.7; range: 24.1-84.6). No associations were observed between the Australian DGI and cognition or brain MRI measures. T2D did not modify any associations (P > 0.05).Conclusions: This is the first study to investigate associations between adherence to the ADG and brain health in the older adults with and without T2D. Future prospective studies are required to clarify if there are long-term associations. [ABSTRACT FROM AUTHOR]

Background: Unhealthy dietary patterns (DPs) are associated with poorer cognition, but few studies have investigated the underlying brain structural mechanisms.Objective: We aimed to examine the relations between DPs, brain structure, and cognition in older people with and without type 2 diabetes.Methods: This cross-sectional study consisted of a sample of people with (n = 343) and without type 2 diabetes (n = 346) aged 55-90 y. The 80-item Cancer Council of Victoria FFQ was used to assess dietary intake. Two DPs (prudent and traditional) for people with type 2 diabetes and 3 DPs (prudent, traditional, and Western) for those without type 2 diabetes were derived using principal component analysis. Neuropsychological tests assessed 6 cognitive domains. Brain MRI was performed to obtain gray, white matter, and hippocampal volumes and markers of small vessel disease (microbleeds, infarcts, and white matter hyperintensities). Multivariable linear regression was used to assess the cross-sectional associations between DPs, brain MRI, and cognitive variables.Results: For those without type 2 diabetes, higher adherence to the Western DP was associated with lower gray matter volume (β = -3.03 95% CI: -5.67, -0.38; P = 0.03). The addition of a cardiovascular risk score, mood, and physical activity weakened associations such that they were no longer significant (β = -1.97 (95% CI: -4.68, 0.74) P = 0.15) for the Western DP. There were no significant associations for the other DPs in people with and without type 2 diabetes.Conclusions: In this cross-sectional study, DPs were not independently associated with brain structure in people with or without type 2 diabetes. Future prospective studies are needed to clarify the role of vascular risk factors on associations between DPs and brain health. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes (T2D) is associated with an increased risk of cognitive impairment and dementia with poorly understood underlying mechanisms.Objective: We examined the role of blood pressure (BP), aortic stiffness, and hemodynamics in this association.Methods: Cross-sectional sample of late middle-aged twins discordant for T2D from the Australian Twin Registry. Measurements included neuropsychological battery and brain MRI including arterial spin labelling (ASL) to measure cerebral perfusion. Mobil-o-Graph devices were used to non-invasively obtain 24-hour BP, aortic stiffness, and hemodynamic measures. Using mixed modelling, we studied associations of T2D with cognition, MRI measures, BP, aortic stiffness, and hemodynamics.Results: There were 23 twin pairs with mean age 63.7 (SD = 6.1) years. T2D (β=-0.45, p < 0.001) and age (β=-0.05, p = 0.022) were independently associated with poorer attention but not with memory or perceptual speed. T2D was associated with reduced nocturnal central systolic BP dipping (β=-3.79, p = 0.027), but not with BP, aortic stiffness, cerebral perfusion, or other hemodynamic measures. There was a statistically significant interaction between T2D and central systolic BP dipping in predicting attention scores (both p < 0.05 for the interaction term) whereby there was a positive association between BP dipping and attention scores in those with T2D, but not in those without T2D.Conclusion: We found an association between T2D and reduced nocturnal central systolic dipping, but not with any other measures of BP, stiffness or hemodynamic measures. Further study of the role of nocturnal central BP dipping in the association between T2D and cognitive impairment may help identify potential mechanisms. [ABSTRACT FROM AUTHOR]

Background: Hypertension is an established risk factor for dementia. However, it is unclear whether there are differential effects of angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blockers (ARB) on brain health. In human observational studies, the evidence for superiority of either agent remains unclear.Objective: To compare brain atrophy and cognitive decline between people treated with ACEi or ARB.Methods: Participants aged 55-90 years without dementia had brain magnetic resonance imaging and neuropsychological assessments performed at 3 time points. The sample was enriched with people with type 2 diabetes (T2D). Multivariable mixed models were used to examine longitudinal associations of antihypertensive medication class with change in cognition and total brain volume.Results: Of 565 people with longitudinal data, there were 163 on ACEi (mean age 69.9 years, T2D:64% with) and 125 on ARB (mean age 69.6 years, T2D:62%) at baseline. The baseline characteristics of those taking either an ACEi or ARB were similar with regards to age, sex, blood pressure control, and vascular risk factors. The mean duration of follow up was 3.2 years. The baseline association of ACEi and ARB use with total brain volume was similar in both groups. However, those taking an ARB had a slower rate of brain atrophy than those taking an ACEi (p = 0.031). Neither ACEi nor ARB use was associated with baseline cognitive function or cognitive decline.Conclusions: These results support the theory that ARB may be preferable to ACEi to reduce brain atrophy. The mechanisms underlying this differential association warrant further investigation. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is associated with an elevated risk of cognitive impairment and dementia. Cerebrovascular disease and neurodegeneration are two major pathways that may explain the effect of diabetes on the brain and therefore deserve investigation. Neuroimaging provides an effective way to investigate the contribution of these pathways in vivo, guiding further mechanistic research and providing biomarkers for clinical correlation or interventional studies. In this paper, we present a narrative review of the state of play with neuroimaging evidence in studies of people with diabetes mellitus, how these data are useful in understanding mechanistic links between diabetes and brain impairment, and possible ways that the field may develop in the future. [ABSTRACT FROM AUTHOR]

An inflammatory diet is related to poorer cognition, but the underlying brain pathways are unknown. The aim of this study was to examine associations between the Energy-Adjusted Dietary Inflammatory Index (E-DII) and brain volume, small vessel disease, and cognition in people with and without type 2 diabetes mellitus (T2DM). This is a secondary cross-sectional analysis of data from the Cognition and Diabetes in Older Tasmanians study. This study included 641 participants (n = 326 with T2DM) enrolled between 2005 and 2011 from Tasmania, Australia. The E-DII was computed from the 80-item Dietary Questionnaire for Epidemiological Studies, version 2. Brain volumes (gray matter, white matter, and white matter hyperintensities), infarcts, and microbleeds were obtained from magnetic resonance imaging. Global cognition was derived from a comprehensive battery of neuropsychological tests. Logistic and linear regressions were performed to examine associations between E-DII and brain measures and a global cognitive score, adjusting for demographics, energy, T2DM, mood, ambulatory activity, and cardiovascular risk factors. An E-DII × T2DM interaction term was tested in each model. The mean (standard deviation) age of participants was 69.8 (7.4) years. There were no associations between the E-DII and any of the brain structural measures or global cognitive function in fully adjusted models. There was a modification effect for T2DM on the association between E-DII and gray matter volume (T2DM: β = 1.38, 95% CI –3.03 to 5.79; without T2DM: β = –4.34, 95% CI, –8.52 to –0.16), but not with any of the other outcome measures. In this cross-sectional study, E-DII was not associated with brain structure or global cognition. In 1 of the 7 outcomes, a significant modification effect for T2DM was found for the associations between E-DII and gray matter. Future prospective studies are needed to clarify the associations between diet-related inflammation and brain health. [ABSTRACT FROM AUTHOR]