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Introduction: There are limited data on prevalence of dementia in centenarians and near-centenarians (C/NC), its determinants, and whether the risk of dementia continues to rise beyond 100., Methods: Participant-level data were obtained from 18 community-based studies (N = 4427) in 11 countries that included individuals ≥95 years. A harmonization protocol was applied to cognitive and functional impairments, and a meta-analysis was performed., Results: The mean age was 98.3 years (SD = 2.67); 79% were women. After adjusting for age, sex, and education, dementia prevalence was 53.2% in women and 45.5% in men, with risk continuing to increase with age. Education (OR 0.95;0.92-0.98) was protective, as was hypertension (odds ratio [OR] 0.51;0.35-0.74) in five studies. Dementia was not associated with diabetes, vision and hearing impairments, smoking, and body mass index (BMI)., Discussion: Among the exceptional old, dementia prevalence remains higher in the older participants. Education was protective against dementia, but other factors for dementia-free survival in C/NC remain to be understood., (© 2022 The Authors. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

Background: Besides physical activity as a target for dementia prevention, sedentary behaviour is hypothesized to be a potential target in its own right. The rising number of persons with dementia and lack of any effective treatment highlight the urgency to better understand these modifiable risk factors. Therefore, we aimed to investigate whether higher levels of sedentary behaviour are associated with reduced global cognitive functioning and slower cognitive decline in older persons without dementia., Methods: We used five population cohorts from Greece, Australia, USA, Japan, and Singapore (HELIAD, PATH, SALSA, SGS, and SLAS2) from the Cohort Studies of Memory in an International Consortium. In a coordinated analysis, we assessed the relationship between sedentary behaviour and global cognitive function with the use of linear mixed growth model analysis (mean follow-up range of 2.0-8.1 years)., Results: Baseline datasets combined 10,450 older adults without dementia with a mean age range between cohorts of 66.7-75.1 years. After adjusting for multiple covariates, no cross-sectional association between sedentary behaviour and cognition was found in four studies. One association was detected where more sedentary behaviour was cross-sectionally linked to higher cognition levels (SLAS2, B = 0.118 (0.075; 0.160), P < 0.001). Longitudinally, there were no associations between baseline sedentary behaviour and cognitive decline (P > 0.05)., Conclusions: Overall, these results do not suggest an association between total sedentary time and lower global cognition in older persons without dementia at baseline or over time. We hypothesize that specific types of sedentary behaviour may differentially influence cognition which should be investigated further. For now, it is, however, too early to establish undifferentiated sedentary time as a potential effective target for minimizing cognitive decline in older adults without dementia.

Background: There is widespread consumer concern that statin use may be associated with impaired memory and cognitive decline., Objectives: This study sought to examine the association between statin use and changes in memory and global cognition in the elderly population over 6 years and brain volumes over 2 years. Interactions between statin use and known dementia risk factors were examined., Methods: Prospective observational study of community-dwelling elderly Australians age 70 to 90 years (the MAS [Sydney Memory and Ageing Study], n = 1,037). Outcome measures were memory and global cognition (by neuropsychological testing every 2 years) and total brain, hippocampal and parahippocampal volumes (by magnetic resonance) in a subgroup (n = 526). Analyses applied linear mixed modeling, including the covariates of age, sex, education, body mass index, heart disease, diabetes, hypertension, stroke, smoking, and apolipoprotein Eε4 carriage. Interactions were sought between statin use and dementia risk factors., Results: Over 6 years there was no difference in the rate of decline in memory or global cognition between statin users and never users. Statin initiation during the observation period was associated with blunting the rate of memory decline. Exploratory analyses found statin use was associated with attenuated decline in specific memory test performance in participants with heart disease and apolipoprotein Eε4 carriage. There was no difference in brain volume changes between statin users and never users., Conclusions: In community-dwelling elderly Australians, statin therapy was not associated with any greater decline in memory or cognition over 6 years. These data are reassuring for consumers concerned about statin use and risk of memory decline., (Crown Copyright © 2019. Published by Elsevier Inc. All rights reserved.)

Background: With no effective treatments for cognitive decline or dementia, improving the evidence base for modifiable risk factors is a research priority. This study investigated associations between risk factors and late-life cognitive decline on a global scale, including comparisons between ethno-regional groups., Methods and Findings: We harmonized longitudinal data from 20 population-based cohorts from 15 countries over 5 continents, including 48,522 individuals (58.4% women) aged 54-105 (mean = 72.7) years and without dementia at baseline. Studies had 2-15 years of follow-up. The risk factors investigated were age, sex, education, alcohol consumption, anxiety, apolipoprotein E ε4 allele (APOE*4) status, atrial fibrillation, blood pressure and pulse pressure, body mass index, cardiovascular disease, depression, diabetes, self-rated health, high cholesterol, hypertension, peripheral vascular disease, physical activity, smoking, and history of stroke. Associations with risk factors were determined for a global cognitive composite outcome (memory, language, processing speed, and executive functioning tests) and Mini-Mental State Examination score. Individual participant data meta-analyses of multivariable linear mixed model results pooled across cohorts revealed that for at least 1 cognitive outcome, age (B = -0.1, SE = 0.01), APOE*4 carriage (B = -0.31, SE = 0.11), depression (B = -0.11, SE = 0.06), diabetes (B = -0.23, SE = 0.10), current smoking (B = -0.20, SE = 0.08), and history of stroke (B = -0.22, SE = 0.09) were independently associated with poorer cognitive performance (p < 0.05 for all), and higher levels of education (B = 0.12, SE = 0.02) and vigorous physical activity (B = 0.17, SE = 0.06) were associated with better performance (p < 0.01 for both). Age (B = -0.07, SE = 0.01), APOE*4 carriage (B = -0.41, SE = 0.18), and diabetes (B = -0.18, SE = 0.10) were independently associated with faster cognitive decline (p < 0.05 for all). Different effects between Asian people and white people included stronger associations for Asian people between ever smoking and poorer cognition (group by risk factor interaction: B = -0.24, SE = 0.12), and between diabetes and cognitive decline (B = -0.66, SE = 0.27; p < 0.05 for both). Limitations of our study include a loss or distortion of risk factor data with harmonization, and not investigating factors at midlife., Conclusions: These results suggest that education, smoking, physical activity, diabetes, and stroke are all modifiable factors associated with cognitive decline. If these factors are determined to be causal, controlling them could minimize worldwide levels of cognitive decline. However, any global prevention strategy may need to consider ethno-regional differences., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: AEA is a consultant for Kinsa Inc. and has received an unrestricted gift from Gojo Inc. CB is a member of the Editorial Board of PLOS Medicine. HB is on the Advisory Board of Nutricia Australia. MG was on Biogen Inc’s “Patient Journey Advisory Group” in 2016 and 2017. NS reports personal fees from Merck Consumer Health and the NIH outside the submitted work. RBL is the Edwin S. Lowe Professor of Neurology at the Albert Einstein College of Medicine in New York. He receives research support from the NIH: 2PO1 AG003949 (mPI), 5U10 NS077308 (PI), RO1 NS082432 (Investigator), 1RF1 AG057531 (Site PI), RF1 AG054548 (Investigator), 1RO1 AG048642 (Investigator), R56 AG057548 (Investigator), K23 NS09610 (Mentor), K23AG049466 (Mentor), 1K01AG054700 (Mentor). He also receives support from the Migraine Research Foundation and the National Headache Foundation. He serves on the editorial board of Neurology, senior advisor to Headache, and associate editor to Cephalalgia. He has reviewed for the NIA and NINDS, holds stock options in eNeura Therapeutics and Biohaven Holdings; serves as consultant, advisory board member, or has received honoraria from: American Academy of Neurology, Alder, Allergan, American Headache Society, Amgen, Autonomic Technologies, Avanir, Biohaven, Biovision, Boston Scientific, Dr. Reddy’s, Electrocore, Eli Lilly, eNeura Therapeutics, GlaxoSmithKline, Merck, Pernix, Pfizer, Supernus, Teva, Trigemina, Vector, Vedanta. He receives royalties from Wolff’s Headache 7th and 8th Edition, Oxford Press University, 2009, Wiley and Informa. PSS received grant funding from the NIH/NIA (USA) and the NHMRC (Australia), as well as philanthropic funding through The Dementia Momentum. He is on the Australian Advisory Board of Biogen Pharmaceuticals. All other authors have declared that no competing interests exist.

Current social phobia models (e.g., Clark & Wells, 1995; Leary & Kowalski, 1995) postulate that socially anxious individuals negatively appraise their anxiety sensations (e.g., sweating, heart racing, blushing) as evidence of poor social performance, and thus fear these anxiety symptoms will be noticed and judged negatively by others. Consequently, they become self-focused and hypervigilant of these sensations and use them to judge how they appear to others. To test this model, high (N=41) and low (N=38) socially anxious participants were shown false physiological feedback regarding an increase or decrease in heart rate prior to and during an impromptu speech task. Relative to participants who observed a false heart rate decrease, those in the increase condition reported higher levels of negative affect, more negative performance appraisals, and more frequent negative ruminative thoughts, and these effects were mediated by an increase in self-focused attention. The unhelpful effects of the physiological feedback were not specific to high socially anxious participants. The results have implications for current cognitive models as well as the treatment of social phobia., (Copyright © 2012. Published by Elsevier Ltd.)

Numerous studies have shown that social phobia patients experience negative self-impressions or images during social situations. Clark and Wells (1995) posited that such negative self-images are involved in the maintenance of social phobia. Thus, the present study investigated the effects of negative self-imagery on cognition and emotion during and following a brief social situation. Specifically, high and low socially anxious participants (N = 77) were instructed to hold either a negative or control self-image as they engaged in a brief speech. Participants then rated their anxiety, performance, cognitions, and focus of attention. Twenty-four hours later, they returned to the laboratory and completed questionnaires assessing the amount of post-event processing (PEP) they engaged in. The results showed that, irrespective of the level of social anxiety or depressive symptoms, participants that held the negative self-image experienced higher levels of anxiety, were more self-focused, experienced more negative thoughts, rated their anxiety as more visible, appraised their performance more negatively, and engaged in more negative and less positive PEP than participants that held the control self-image. Collectively the results indicate that negative imagery is causally involved in the maintenance of social phobia, as well as in the generation of social anxiety among non-anxious individuals., (Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.)