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Aim: To examine the associations between visceral adipose tissue (VAT) and brain structural measures at midlife and explore how these associations may be affected by age, sex and cardiometabolic factors. Methods: We used abdominal and brain magnetic resonance imaging data from a population‐based cohort of people at midlife in the UK Biobank. Regression modelling was applied to study associations of VAT volume with total brain volume (TBV), grey matter volume (GMV), white matter volume, white matter hyperintensity volume (WMHV) and total hippocampal volume (THV), and whether these associations were altered by age, sex or cardiometabolic factors. Results: Complete data were available for 17 377 participants (mean age 63 years, standard deviation = 12, 53% female). Greater VAT was associated with lower TBV, GMV and THV (P <.001). We found an interaction between VAT and sex on TBV (P <.001), such that the negative association of VAT with TBV was greater in men (β = −2.89, 95% confidence interval [CI] −2.32 to −10.15) than in women (β = −1.32, 95% CI −0.49 to −3.14), with similar findings for GMV. We also found an interaction between VAT and age (but not sex) on WMHV (P <.001). The addition of other cardiometabolic factors or measures of physical activity resulted in little change to the models. Conclusions: VAT volume is associated with poorer brain health in midlife and this relationship is greatest in men and those at younger ages. [ABSTRACT FROM AUTHOR]

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 Inpatient delirium is common and associated with poor outcomes. Although most organisations have evidence-based guidelines to improve delirium prevention and management, delirium rates and outcomes have remained relatively unchanged over time. A lack of understanding of healthcare providers' experience of caring for people with delirium and its integration into existing guidance may explain some of the slow progress in improving delirium care. Objective To review and synthesise existing qualitative evidence on healthcare providers' experience of caring for inpatients with delirium within and across disciplines. Methods We systematically searched OVID Medline, CINAHL, Embase, Emcare, PsychINFO, AMED and Web of Science databases for articles published between January 1990 and November 2022. Article inclusion and study quality were assessed by two independent reviewers. Both thematic synthesis and content analysis were then conducted to synthesise findings from included studies. Results Within the 25 included studies, the experience of nurses was the most commonly studied perspective, followed by medical and allied health. Nursing, medical and allied health staff all reported that their experience of caring for people with delirium was challenging, highlighting difficulties in delirium recognition and that they felt unsupported at organisational and local levels. Attitudes towards older people and the importance of delirium influenced identification and prioritisation. Conclusions Healthcare providers often find caring for hospitalised patients with delirium challenging and complex. Although good communication within multidisciplinary teams was deemed helpful, more work is required to understand how to achieve this, recognising the unique perspectives of individual disciplines. [ABSTRACT FROM AUTHOR]

Rising rates of insulin resistance and an ageing population are set to exact an increasing toll on individuals and society. Here we examine the contribution of age and insulin resistance to the association of cerebral blood flow and glucose metabolism; both critical process in the supply of energy for the brain. Thirty-four younger (20–42 years) and 41 older (66–86 years) healthy adults underwent a simultaneous resting state MR/PET scan, including arterial spin labelling. Rates of cerebral blood flow and glucose metabolism were derived using a functional atlas of 100 brain regions. Older adults had lower cerebral blood flow than younger adults in 95 regions, reducing to 36 regions after controlling for cortical atrophy and blood pressure. Lower cerebral blood flow was also associated with worse working memory and slower reaction time in tasks requiring cognitive flexibility and response inhibition. Younger and older insulin sensitive adults showed small, negative correlations between relatively high rates of regional cerebral blood flow and glucose metabolism. This pattern was inverted in insulin resistant older adults, who showed hypoperfusion and hypometabolism across the cortex, and a positive correlation. In insulin resistant younger adults, the association showed inversion to positive correlations, although not to the extent seen in older adults. Our findings suggest that the normal course of ageing and insulin resistance alter the rates of and associations between cerebral blood flow and glucose metabolism. They underscore the criticality of insulin sensitivity to brain health across the adult lifespan. [ABSTRACT FROM AUTHOR]

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.)