COGNITIVE CORRELATES OF GAIT SPEED AMONG OLDER ADULTS FROM SIX COUNTRIES: FINDINGS FROM THE COSMIC COLLABORATION

Using data from population-based cohorts of older adults 65+ from six countries across three continents (N=6472), we aimed to (1) describe and (2) identify predictors of usual and rapid gait speed from studies participating in the Cohort Studies of Memory in an International Consortium (COSMIC) collaboration. We investigated whether clinical (BMI, hypertension, stroke, APOE status), psychological (cognition, mood, general health) and behavioral factors (smoking, drinking, physical activity) predicted gait speed similarly across cohorts; we used regression models controlling for demographics. Unadjusted usual gait speed ranged from 0.52-1.09 m/s and rapid gait speed ranged from 1.20-1.68 m/s. Lower BMI and better cognitive function consistently predicted faster usual and rapid gait speed in all cohorts. These patterns were not attenuated by demographics. Other psychological and behavioral factors were less consistently associated with gait. Taken together, gait speed is variable across ethnogeographic regions, but the influence of cognitive on gait is remarkably consistent

Prevalence of burnout among teachers during the Covid-19 pandemic: a meta-analysis

Since the start of the COVID-19 pandemic, many studies have found that there has been a lot of teacher overload. One of the additional burdens has been that they have had to teach online. In addition, when they returned to face-to-face classes, they had to follow all the hygiene rules so that the COVID-19 virus would not spread. It is therefore not surprising that, during this pandemic period, high levels of psychological symptoms have been reported among teachers. Among this symptomatology, burnout has been very frequent among teachers. Therefore, the aim of this study is to conduct a meta-analysis to determine the overall prevalence of burnout among teachers during the COVID-19 pandemic. For this purpose, a search was conducted for cross-sectional studies listed in PubMed from 1 December 2019 to 14 February 2022 that reported on the prevalence of burnout among teachers. A total of nine studies from eight different countries in Africa, Asia, Europe, and North and South America, were included in this study. The pooled prevalence of burnout among teachers was 52% (95% CI 33–71%), which is higher than burnout rates reported for health professionals. There was significant heterogeneity between studies (I2 = 99%, p-value < 0.001), and the prevalence of burnout was higher in women and school teachers (compared to university educators), and lower in American studies. This meta-analysis concludes that teachers worldwide experienced a high rate of burnout during the COVID-19 pandemic. This has implications not only for the teachers themselves, but also for the quality of the education they were able to provide. This education has an influence on the student population. The possible long-term effects are yet to be determined

Bed rest and cognition: effects on executive functioning and reaction time

INTRODUCTION: Executive functions are high-order aspects of cognition heavily dependent upon the prefrontal cortex. Both prefrontal cortex activity and executive function task performance are enhanced by participation in aerobic physical activity, suggesting that a lack of such activity during the bed rest model of prolonged weightlessness might induce executive function deficits. METHODS: Twenty-four healthy males (ages 21-45 yr) undertook 60 d of head-down bed rest (-6 degrees) for the 2nd Berlin Bed Rest Study (BBR2-2). Three executive function tasks (Iowa Gambling Task, working memory, and flanker) and a reaction time task were administered before, during, and after bed rest. RESULTS: Iowa Gambling Task scores were significantly worse during bed rest (1.7 +/- 6.9) than in other sessions (24.3 +/- 7.8). Effects on working memory and flanker task performance were less obvious, requiring practice effects to be considered. Reaction time was significantly slower after bed rest (569 +/- 42 ms) than in earlier tests (529 +/- 45 ms). There was also significantly less intrasubject variability in reaction time after bed rest, consistent with more efficient executive functioning at this stage. DISCUSSION: Our results provide some evidence for a detrimental effect of bed rest on executive functioning. Whether this stems from a lack of aerobic physical activity and/or changes in the prefrontal cortex remains to be determined. Cognitive effects of bed rest could have implications for the planned human exploration of Mars, and for medical and lifestyle conditions with inadequate levels of aerobic physical activity

Does Anxiety Increase the Risk of all-Cause Dementia? An Updated Meta-Analysis of Prospective Cohort Studies

Background:Anxiety has been suggested as a potentially modifiable risk factor for dementia, but results are still controversial. Our main objectives are to develop an updated meta-analysis of prospective population-based studies on the relationship between anxiety and risk of dementia, and to estimate the population fraction of dementia attributable to anxiety (PAF).Methods:We searched for cohort studies listed on PubMed or Web of Science from January 2018 to January 2020 that reported risk estimates for the association between anxiety and incident dementia. These were added to cohort studies published before January 2018 that were used in a previously published meta-analysis. Fully adjusted RRs were pooled using random effects models. We estimated the proportion of incident dementia attributable to anxiety by using PAF.Results:The meta-analysis included nine prospective cohorts from eight studies, representing 29, 608 participants. The overall relative risk (RR) of dementia was 1.24 (95% CI: 1.06-1.46) and the PAF of dementia due to anxiety was 3.9%.Conclusions:Anxiety is significantly associated with an increased risk of all-cause dementia. The treatment or prevention of anxiety might help to reduce dementia incidence rates, but more research is needed to clarify whether anxiety is a cause of dementia rather than a prodrome

Association between anxiety and vascular dementia risk: new evidence and an updated meta-analysis

The association between anxiety and vascular dementia (VaD) is unclear. We aimed to reliably estimate the association between anxiety and VaD risk using meta-analysis to pool new results from a large community-based cohort (Zaragoza Dementia and Depression (ZARADEMP) study) and results from previous studies. ZARADEMP participants (n = 4057) free of dementia were followed up on for up to 12 years. Cases and subcases of anxiety were determined at baseline. A panel of four psychiatrists diagnosed incident cases of VaD by consensus. We searched for similar studies published up to October 2019 using PubMed and Web of Science. Observational studies reporting associations between anxiety and VaD risk, and adjusting at least for age, were selected. Odds ratios (ORs) from each study were combined using fixed-effects models. In the ZARADEMP study, the risk of VaD was 1.41 times higher among individuals with anxiety (95% CI: 0.75-2.68) compared with non-cases (p = 0.288). Pooling this result with results from two previous studies yielded an OR of 1.65 (95% CI: 1.07-2.53; p = 0.022). These findings indicate that anxiety is associated with an increased risk of VaD. Taking into account that anxiety is commonly observed in the elderly, treating and preventing it might reduce the prevalence and incidence of VaD. However, whether anxiety is a cause of a prodrome of VaD is still unknown, and future research is needed to clarify this

Age-related cognitive decline and associations with sex, education and apolipoprotein E genotype across ethnocultural groups and geographic regions: a collaborative cohort study

Background: The prevalence of dementia varies around the world, potentially contributed to by international differences in rates of age-related cognitive decline. Our primary goal was to investigate how rates of age-related decline in cognitive test performance varied among international cohort studies of cognitive aging. We also determined the extent to which sex, educational attainment, and apolipoprotein E ε4 allele (APOE*4) carrier status were associated with decline. Methods and findings: We harmonized longitudinal data for 14 cohorts from 12 countries (Australia, Brazil, France, Greece, Hong Kong, Italy, Japan, Singapore, Spain, South Korea, United Kingdom, United States), for a total of 42,170 individuals aged 54–105 y (42% male), including 3.3% with dementia at baseline. The studies began between 1989 and 2011, with all but three ongoing, and each had 2–16 assessment waves (median = 3) and a follow-up duration of 2–15 y. We analyzed standardized Mini-Mental State Examination (MMSE) and memory, processing speed, language, and executive functioning test scores using linear mixed models, adjusted for sex and education, and meta-analytic techniques. Performance on all cognitive measures declined with age, with the most rapid rate of change pooled across cohorts a moderate -0.26 standard deviations per decade (SD/decade) (95% confidence interval [CI] [-0.35, -0.16], p < 0.001) for processing speed. Rates of decline accelerated slightly with age, with executive functioning showing the largest additional rate of decline with every further decade of age (-0.07 SD/decade, 95% CI [-0.10, -0.03], p = 0.002). There was a considerable degree of heterogeneity in the associations across cohorts, including a slightly faster decline (p = 0.021) on the MMSE for Asians (-0.20 SD/decade, 95% CI [-0.28, -0.12], p < 0.001) than for whites (-0.09 SD/decade, 95% CI [-0.16, -0.02], p = 0.009). Males declined on the MMSE at a slightly slower rate than females (difference = 0.023 SD/decade, 95% CI [0.011, 0.035], p < 0.001), and every additional year of education was associated with a rate of decline slightly slower for the MMSE (0.004 SD/decade less, 95% CI [0.002, 0.006], p = 0.001), but slightly faster for language (-0.007 SD/decade more, 95% CI [-0.011, -0.003], p = 0.001). APOE*4 carriers declined slightly more rapidly than non-carriers on most cognitive measures, with processing speed showing the greatest difference (-0.08 SD/decade, 95% CI [-0.15, -0.01], p = 0.019). The same overall pattern of results was found when analyses were repeated with baseline dementia cases excluded. We used only one test to represent cognitive domains, and though a prototypical one, we nevertheless urge caution in generalizing the results to domains rather than viewing them as test-specific associations. This study lacked cohorts from Africa, India, and mainland China. Conclusions: Cognitive performance declined with age, and more rapidly with increasing age, across samples from diverse ethnocultural groups and geographical regions. Associations varied across cohorts, suggesting that different rates of cognitive decline might contribute to the global variation in dementia prevalence. However, the many similarities and consistent associations with education and APOE genotype indicate a need to explore how international differences in associations with other risk factors such as genetics, cardiovascular health, and lifestyle are involved. Future studies should attempt to use multiple tests for each cognitive domain and feature populations from ethnocultural groups and geographical regions for which we lacked dataFunding for each of the contributing studies is as follows: The Brazilian Ministry of Health and Ministry of Science and Technology (MFLC, ECC); Major awards from the UK Medical Research Council and the Department of Health (CB, FEM, BCMS); National Institute on Health/National Institute on Aging grants (5P01 AG003949, 1R03 AG045474; RBL, MJK); Novartis (KR, JS, MLA); Alzheimer’s Association (IIRG-09- 133014), ESPA-EU program Excellence Grant (ARISTEIA), which is co-funded by the European Social Fund and Greek National resources (189 10276/8/9/2011), and Ministry for Health and Social Solidarity, Greece (ΔY2β/οικ.51657/ 14.4.2009; NS, MY, ED); Mr. Lai Seung Hung & Mrs. Lai Chan Pui Ngong Dementia in Hong Kong Research Fund, and an educational fund from Eisai (LCWL, CHYW, AWTF); Fondazione Golgi Cenci and Federazione Alzheimer Italia (AG, RV, AD); Korean Health Technology R&D Project, Ministry of Health and Welfare, Republic of Korea [Grant No. HI09C1379 (A092077); KWK, JWH, THK]; National Health and Medical Research Council of Australia (Grants 973302, 179805, 157125 and 1002160; KJA, NC, PB); Wellcome Trust (grant code GR066133MA) and FAPESP-Brazil (grant code 2004/12694-8; MS); Health and Labour Sciences Research Grant from the Ministry of Health, Labour and Welfare of Japan (H25-Ninchisho-Ippan-004) and a research grant from Sasaguri town, Fukuoka, Japan (SK, SC, KN); Research grants (No. 03/ 121/17/214 and No. 08/1/21/19/567) from the Biomedical Research Council, Agency for Science, Technology and Research (A_STAR) in Singapore (TPN, QG); National Health & Medical Research Council of Australia Program Grant (ID 350833; PSS, DML, NAK, JDC, AT, GA, SR, HB); Fondo de Investigacio´n Sanitaria, Instituto de Salud Carlos III, Spanish Ministry of Health, Madrid, Spain (Grants 94/ 1562, 97/1321E, 98/0103, 01/0255, 03/0815, 06/0617, and G03/128) and Pfizer Foundation, Madrid (AL, RLA, JS). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript