To determine the relationship between the amount and intensity of physical activity performed by older adults in North America (United States and Canada) and their depression and anxiety symptoms ...while currently under social distancing guidelines (SDG) for the COVID-19 pandemic.
Descriptive cross-sectional study.
Online survey conducted between April 9 and April 30, 2020, during the COVD-19 pandemic.
About 1,046 older adults over the age of 50 who live in North America.
Participants were asked about their basic demographic information, current health status, and the impact of the current SDG on their subjective state of mental health. Participants completed the Physical Activity Scale for the Elderly, to determine the amount and intensity of physical activity performed, as well as both the Geriatric Depression Scale and Geriatric Anxiety Scale, to ascertain the extent of their depression and anxiety-like symptoms.
Ninety-seven percent of participants indicated that they adhered to current SDG "Most of the time" or "Strictly." Participants who performed greater levels of physical activity experienced lower levels of depression-like symptoms when age, sex, and education were accounted for; however, no relationship between physical activity and anxiety-like symptoms was found. A hierarchical regression analysis that incorporated the intensity of physical activity performed (light, moderate, and vigorous) in the model indicated that greater light and strenuous activity, but not moderate, predicted lower depression-like symptoms.
These results suggest that performing even light physical activity during the COVID-19 pandemic may help alleviate some of the negative mental health impacts that older adults may be experiencing while isolated and adhering to SDG during the COVID-19 pandemic.
Objective: Over the last 25 years, there has been an unprecedented increase in federal funding for large-scale longitudinal studies, many of which collect neuropsychological or neuroimaging outcome ...measures. These studies have collected data from thousands of study participants across multiple waves of data collection over many years. With the increased availability of longitudinal data, data sharing policies have become more liberal, thereby offering significant opportunities for interested researchers to carry out their own longitudinal research with these data. At the same time, these opportunities have stimulated new conceptualizations of longitudinal change and have led to the development of novel approaches toward analysis of longitudinal data. My aim is to review these new conceptualizations and novel data analytic approaches. Method: In this article, I describe the state of the field a quarter century ago with respect to available longitudinal studies, and I trace the growth of federally funded longitudinal studies over the last 25 years by describing 18 of these projects, many of which are still collecting data. In the second part of this article, I describe changes in the methods used to analyze longitudinal data, transitioning from the paired t test and repeated measures ANOVA to latent change scores, linear mixed effects modeling, and latent growth curve models. Changes in the approach to management of missing data are also discussed. Conclusions: Future studies should abandon traditional longitudinal analytic methods in favor of contemporary approaches given their increased power, greater accuracy, and widespread availability.
General Scientific Summary
This article describes a number of federally funded longitudinal research studies in cognitive aging and Alzheimer's disease that have made significant contributions to our understanding of longitudinal changes in normal and pathological aging, and it underscores the rapid rise of these funded studies over the last 25 years. The article also considers significant shortcomings and limitations associated with traditional approaches to longitudinal data analysis, such as the paired t test and repeated measures analysis of variance. Finally, contemporary methods are presented for management of missing data and for longitudinal data analysis, including linear mixed effects modeling, latent growth curve analysis, latent change scores, and generalized estimating equations, and the article illustrates the advantages of these contemporary approaches over traditional methods of analysis.
Mild traumatic brain injury (mTBI) is a significant healthcare burden and its diagnosis remains a challenge in the emergency department. Serum biomarkers and advanced magnetic resonance imaging (MRI) ...techniques have already demonstrated their potential to improve the detection of brain injury even in patients with negative computed tomography (CT) findings. The objective of this study was to determine the clinical value of a combinational use of both blood biomarkers and MRI in mTBI detection and their characterization in the acute setting (within 24 hours after injury).
Nine patients with mTBI were prospectively recruited from the emergency department. Serum samples were collected at the time of hospital admission and every 6 hours up to 24 hours post injury. Neuronal (Ubiquitin C-terminal Hydrolase-L1 UCH-L1) and glial (glial fibrillary acidic protein GFAP) biomarker levels were analyzed. Advanced MRI data were acquired at 9 ± 6.91 hours after injury. Patients' neurocognitive status was assessed by using the Standard Assessment of Concussion (SAC) instrument.
The median serum levels of UCH-L1 and GFAP on admission were increased 4.9 folds and 10.6 folds, respectively, compared to reference values. Three patients were found to have intracranial hemorrhages on SWI, all of whom had very high GFAP levels. Total volume of brain white matter (WM) with abnormal fractional anisotropy (FA) measures of diffusion tensor imaging (DTI) were negatively correlated with patients' SAC scores, including delayed recall. Both increased and decreased DTI-FA values were observed in the same subjects. Serum biomarker level was not correlated with patients' DTI data nor SAC score.
Blood biomarkers and advanced MRI may correlate or complement each other in different aspects of mTBI detection and characterization. GFAP might have potential to serve as a clinical screening tool for intracranial bleeding. UCH-L1 complements MRI in injury detection. Impairment at WM tracts may account for the patients' neurocognitive symptoms.
Covering: 2006 to 2013. Investigations on the chemistry and biology of rocaglamide, silvestrol and structurally related bioactive compounds from Aglaia species during the period 2006-2013 are ...reviewed. Included are new phytochemical studies of naturally occurring rocaglamide derivatives, an update on synthetic methods for cyclopentabbenzofurans, and a description of the recent biological evaluation and mechanism-of-action studies on compounds of this type.
We examined the impact of physical activity (PA) on longitudinal change in hippocampal volume in cognitively intact older adults at varying genetic risk for the sporadic form of Alzheimer's disease ...(AD). Hippocampal volume was measured from structural magnetic resonance imaging (MRI) scans administered at baseline and at an 18-month follow-up in 97 healthy, cognitively intact older adults. Participants were classified as High or Low PA based on a self-report questionnaire of frequency and intensity of exercise. Risk status was defined by the presence or absence of the apolipoprotein E-epsilon 4 (APOE-ε4) allele. Four subgroups were studied: Low Risk/High PA (n = 24), Low Risk/Low PA (n = 34), High Risk/High PA (n = 22), and High Risk/Low PA (n = 17). Over the 18 month follow-up interval, hippocampal volume decreased by 3% in the High Risk/Low PA group, but remained stable in the three remaining groups. No main effects or interactions between genetic risk and PA were observed in control brain regions, including the caudate, amygdala, thalamus, pre-central gyrus, caudal middle frontal gyrus, cortical white matter (WM), and total gray matter (GM). These findings suggest that PA may help to preserve hippocampal volume in individuals at increased genetic risk for AD. The protective effects of PA on hippocampal atrophy were not observed in individuals at low risk for AD. These data suggest that individuals at genetic risk for AD should be targeted for increased levels of PA as a means of reducing atrophy in a brain region critical for the formation of episodic memories.
ABSTRACTObjectives:Centenarians have survived into very late life, but whether they reach very old age in good health remains unclear. The purpose of this study was to compare the cardiovascular ...health status and cognitive functioning of centenarians in the United States with centenarians in Japan.
This cross-national design compared centenarians from the United States and Japan. The sample of U.S. centenarians was recruited from the Georgia Centenarian Study and included 287 centenarians. The sample of Japanese centenarians was recruited from the Tokyo Centenarian Study and included 304 centenarians.
Cognitive functioning was assessed with a mental status questionnaire, and cardiovascular disease by a health history assessment, blood pressure, and selected blood parameters.
The results suggest that Tokyo centenarians had lower disease experiences and BMI values, when compared to Georgia centenarians, but blood pressure was higher among Japanese centenarians. Lower levels of hemoglobin in Japanese centenarians and higher levels of C-reactive protein in Georgia were also found. The positive association of hypertension and albumin levels with cognitive functioning and the negative association of stroke occurrence with cognitive functioning were replicated in both countries. Differential effects were obtained for heart problems, BMI, and C-reactive protein (with positive effects for Tokyo centenarians, except for C-reactive protein).
For extremely old individuals, some markers of cardiovascular disease are replicable across countries, whereas differential effects for cardiovascular health also need to be considered in cardiovascular health.
Hippocampal sclerosis is a relatively common neuropathological finding (∼10% of individuals over the age of 85 years) characterized by cell loss and gliosis in the hippocampus that is not explained ...by Alzheimer's disease. Hippocampal sclerosis pathology can be associated with different underlying causes, and we refer to hippocampal sclerosis in the aged brain as hippocampal sclerosis associated with ageing. Much remains unknown about hippocampal sclerosis associated with ageing. We combined three different large autopsy cohorts: University of Kentucky Alzheimer's Disease Centre, the Nun Study and the Georgia Centenarian Study to obtain a pool of 1110 patients, all of whom were evaluated neuropathologically at the University of Kentucky. We focused on the subset of cases with neuropathology-confirmed hippocampal sclerosis (n=106). For individuals aged≥95 years at death (n=179 in our sample), each year of life beyond the age of 95 years correlated with increased prevalence of hippocampal sclerosis pathology and decreased prevalence of 'definite' Alzheimer's disease pathology. Aberrant TAR DNA protein 43 immunohistochemistry was seen in 89.9% of hippocampal sclerosis positive patients compared with 9.7% of hippocampal sclerosis negative patients. TAR DNA protein 43 immunohistochemistry can be used to demonstrate that the disease is usually bilateral even when hippocampal sclerosis pathology is not obvious by haematoxylin and eosin stains. TAR DNA protein 43 immunohistochemistry was negative on brain sections from younger individuals (n=10) after hippocampectomy due to seizures, who had pathologically confirmed hippocampal sclerosis. There was no association between cases with hippocampal sclerosis associated with ageing and apolipoprotein E genotype. Age of death and clinical features of hippocampal sclerosis associated with ageing (with or without aberrant TAR DNA protein 43) were distinct from previously published cases of frontotemporal lobar degeneration TAR DNA protein 43. To help sharpen our ability to discriminate patients with hippocampal sclerosis associated with ageing clinically, the longitudinal cognitive profile of 43 patients with hippocampal sclerosis associated with ageing was compared with the profiles of 75 controls matched for age, gender, education level and apolipoprotein E genotype. These individuals were followed from intake assessment, with 8.2 (average) longitudinal cognitive assessments. A neuropsychological profile with relatively high-verbal fluency but low word list recall distinguished the hippocampal sclerosis associated with ageing group at intake (P<0.015) and also 5.5-6.5 years before death (P<0.005). This may provide a first step in clinical differentiation of hippocampal sclerosis associated with ageing versus pure Alzheimer's disease in their earliest stages. In summary, in the largest series of autopsy-verified patients with hippocampal sclerosis to date, we characterized the clinical and pathological features associated with hippocampal sclerosis associated with ageing.
Abstract
Objective
After two stimulus pairs with a common stimulus are presented, healthy adults readily derive multiple indirect associations between each stimulus without explicit training. Factors ...related to this ability to derive new associations are relatively unstudied. We investigated the effects of sex and episodic memory performance on response times (RT) for different stimulus types (letters versus symbols) during trained and derived relational responding.
Method
Ninety-four cognitively healthy young adults were administered a relational responding (RR) task and the Hopkins Verbal Learning Test–Revised (HVLT-R) remotely via videoconferencing. In the RR task, two associations were directly trained in a single learning trial (A → B; A → C). Four other associations can be derived (B → A; C → A; B → C; C → B). Moderated multiple regressions examined main and interaction effects of sex and HVLT-R performance on correct RTs for trained and derived relations between letters and symbols, separately.
Results
Higher HVLT-R immediate and delayed recall scores were associated with faster RTs for all derived, but not trained, relations in the letter (p = 0.001–0.022) and symbol (p = 0.006–0.043) conditions. There was no main effect of sex, but significant sex by HVLT-R interactions were observed for several derived relations in the symbol (p = 0.032–0.044) and letter conditions (p = 0.035). Only males showed a significant RR-HVLT-R association.
Conclusions
After a single presentation of two stimulus pairs, participants learned the two trained associations and independently derived four new, untrained stimulus relations. Better HVLT-R performance predicted faster RT uniquely for derived relations between letters/symbols. This relationship was more robust in males. Future research should evaluate the effectiveness of RR-based interventions for memory rehabilitation.
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