Plasma Neurofilament Light and Markers of Sensorimotor Function in a Predominantly Hispanic Population of Older Adults in San Antonio, Texas

Background: Sensorimotor and blood-based biomarkers are promising dementia biomarkers with high accessibility and limited invasiveness. Although sensorimotor changes appear with aging, more severe changes may precede cognitive decline, dementia, and other neurological diseases. Additionally, blood-based neurofilament light (NfL), a broad marker of neuroaxonal injury, is commonly elevated in many types of neurological disease. Prior studies have suggested that increased blood levels of NfL in conjunction with sensorimotor decline may allow for earlier neurological disease diagnosis and/or prediction of disease severity, but little is known about the correlation of these markers in the general population. We examined the association between NfL and sensorimotor markers in a predominantly Hispanic population in San Antonio, Texas. Method: Our sample included older adults from our San Antonio MarkVCID and South Texas Alzheimer’s Disease Research Center (ADRC) cohorts (n=152, mean age 71.2±7.63, 60.4% women, 79.5% Hispanic) with available plasma NfL, olfaction (B-SIT age-adjusted percentile), grip strength, and touch (monofilament) data (Table 1). NfL concentrations were log-transformed to achieve a normal distribution. We used linear or logistic regression models, as appropriate, to assess the association between NfL and sensorimotor outcomes, adjusting for age, sex, race, ethnicity, and cognitive diagnosis. Result: Higher plasma NfL was significantly associated with decreased olfaction score percentiles (Beta [95% Confidence Interval], β=-8.79; [95% CI -16.89; -0.12], p=0.05), grip strength in either hand (left: β=-3.62; [95% CI -5.51; -1.74], p=0.0002; right: β=-2.99; [95% CI -5.01; -1.03], p=0.003), and impaired touch perception (Odds Ratio [95% CI], OR=2.56; [95% CI 1.01; 6.48]; p=0.05), independent of the potential confounders listed above. Conclusion: These results highlight the association of plasma NfL with several markers of sensorimotor function, which may reflect central and peripheral neuroaxonal injury. Additional studies are needed in larger community samples to confirm these findings and explore the potential of NfL as a marker of functional decline in longitudinal studies. We plan to continue collecting these markers, as well as gait and balance, longitudinally to gain a better understanding of the link between neurodegeneration, sensorimotor markers, and neurological disease trajectory in our unique South Texas population

Preinjury somatization symptoms contribute to clinical recovery after sport-related concussion

OBJECTIVE: To determine the degree to which preinjury and acute postinjury psychosocial and injury-related variables predict symptom duration following sport-related concussion. METHODS: A total of 2,055 high school and collegiate athletes completed preseason evaluations. Concussed athletes (n = 127) repeated assessments serially (<24 hours and days 8, 15, and 45) postinjury. Cox proportional hazard modeling was used to predict concussive symptom duration (in days). Predictors considered included demographic and history variables; baseline psychological, neurocognitive, and balance functioning; acute injury characteristics; and postinjury clinical measures. RESULTS: Preinjury somatic symptom score (Brief Symptom Inventory-18 somatization scale) was the strongest premorbid predictor of symptom duration. Acute (24-hour) postconcussive symptom burden (Sport Concussion Assessment Tool-3 symptom severity) was the best injury-related predictor of recovery. These 2 predictors were moderately correlated (r = 0.51). Path analyses indicated that the relationship between preinjury somatization symptoms and symptom recovery was mediated by postinjury concussive symptoms. CONCLUSIONS: Preinjury somatization symptoms contribute to reported postconcussive symptom recovery via their influence on acute postconcussive symptoms. The findings highlight the relevance of premorbid psychological factors in postconcussive recovery, even in a healthy athlete sample relatively free of psychopathology or medical comorbidities. Future research should elucidate the neurobiopsychosocial mechanisms that explain the role of this individual difference variable in outcome following concussive injury

Prospective, Head-to-Head Study of Three Computerized Neurocognitive Assessment Tools (CNTs): Reliability and Validity for the Assessment of Sport-Related Concussion

Abstract Limited data exist comparing the performance of computerized neurocognitive tests (CNTs) for assessing sport-related concussion. We evaluated the reliability and validity of three CNTs—ANAM, Axon Sports/Cogstate Sport, and ImPACT—in a common sample. High school and collegiate athletes completed two CNTs each at baseline. Concussed ( n =165) and matched non-injured control ( n =166) subjects repeated testing within 24 hr and at 8, 15, and 45 days post-injury. Roughly a quarter of each CNT’s indices had stability coefficients ( M =198 day interval) over .70. Group differences in performance were mostly moderate to large at 24 hr and small by day 8. The sensitivity of reliable change indices (RCIs) was best at 24 hr (67.8%, 60.3%, and 47.6% with one or more significant RCIs for ImPACT, Axon, and ANAM, respectively) but diminished to near the false positive rates thereafter. Across time, the CNTs’ sensitivities were highest in those athletes who became asymptomatic within 1 day before neurocognitive testing but was similar to the tests’ false positive rates when including athletes who became asymptomatic several days earlier. Test–retest reliability was similar among these three CNTs and below optimal standards for clinical use on many subtests. Analyses of group effect sizes, discrimination, and sensitivity and specificity suggested that the CNTs may add incrementally (beyond symptom scores) to the identification of clinical impairment within 24 hr of injury or within a short time period after symptom resolution but do not add significant value over symptom assessment later. The rapid clinical recovery course from concussion and modest stability probably jointly contribute to limited signal detection capabilities of neurocognitive tests outside a brief post-injury window. ( JINS , 2016, 22 , 24–37

Associations between neuropsychiatric symptoms and ADRD serum biomarkers in Mexican American and non-Hispanic white adults with mild cognitive impairment

Background: Mild cognitive impairment (MCI) is a heterogenous diagnostic category with trajectories ranging from reversion to unimpaired cognition to progression to dementia. Neuropsychiatric symptoms such as depression and irritability are common and influence quality of life of patients and caregivers. The role of neuropsychiatric symptoms on disease biology, presentation, and course remains poorly understood. The goal of this study was to evaluate the associations between neuropsychiatric symptoms and serum ADRD biomarkers in Mexican American and non-Hispanic white participants diagnosed with MCI. Method: Participants from the Texas Alzheimer’s Research and Care Consortium underwent a blood draw and clinical evaluation, including psychopathological and cognitive assessments. Diagnoses of MCI were adjudicated in consensus reviews. The presence and severity of neuropsychiatric symptoms were assessed by informant report using the Neuropsychiatric Inventory (NPI). Serum levels of total tau, neurofilament light (NfL), and glial fibrillary acidic protein (GFAP) were assessed using Simoa HD-X Analyzer. Associations between NPI total score and individual items with serum biomarker levels were assessed using linear regression adjusted for age and sex. Result: A total of 425 participants (mean age: 71 ± 9 years, 62% female, 74% Mexican American) had a diagnosis of MCI and serum ADRD biomarkers (Table 1). Total NPI score was not associated with total tau (ß=0.002, p=0.609), NfL (ß=0.001, p=0.658), or GFAP (ß=0.001, p=0.777). However, endorsement of appetite changes was associated with higher NfL (ß=0.077, p=0.006) and GFAP (ß=0.088, p=0.002) levels. Stratified analyses indicated associations of appetite changes with serum NfL (ß=0.108, p=0.002) and GFAP (ß=0.095, p=0.003) in Mexican Americans, but not in non-Hispanic whites (NfL: ß=0.022, p=0.633, GFAP: ß=0.102, p=0.066).There were no other significant associations between individual items on the NPI with serum biomarkers (p\u3e0.05, Bonferroni adjustment p±0.003). Conclusion: Within Mexican American adults with MCI, changes in appetite were associated with higher serum NFL and GFAP levels. As elevations in circulating NfL and GFAP levels are associated with ADRD pathology and accelerated disease progression, appetite changes, a non-invasive and easily discernible behavioral phenotype, may predict higher likelihood of worsening cognitive course. Future longitudinal studies will be necessary to confirm predictive utility of appetite changes for disease progression

Influence of demographic and clinical characteristics on circulating GFAP levels in Mexican American and non-Hispanic white older adults

Background: Circulating levels of glial fibrillary acidic protein (GFAP), an intermediate filament protein of the astrocytic cytoskeleton and putative marker of reactive astrocytosis, increase with cerebral amyloid beta burden and associate with risk of incident all-cause and Alzheimer\u27s disease (AD) dementia. However, further validation in diverse cohorts and evaluation of potential health disparities are necessary for broader generalization. The goal of the present study was to examine the associations between demographics, cardiovascular risk factors, and APOE ε4 status with serum GFAP levels among Mexican American and non-Hispanic white older adults across the continuum from cognitively unimpaired to AD dementia. Method: Participants included 1,156 Mexican American and 587 non-Hispanic white adults, aged 55 years and older, who completed a blood draw, clinical and cognitive evaluations, and dementia consensus reviews as part of the Texas Alzheimer’s Research and Care Consortium. Serum levels of GFAP were assayed using a Simoa HD-1 Analyzer (Quanterix). Associations between demographic and clinical characteristics with serum GFAP levels were evaluated using linear regression. The diagnostic accuracy of serum GFAP was further examined using area under the receiver operating characteristic curves (AUROC) in univariate and adjusted models and optimal cut-points were derived using the maximum Kolmogorov-Smirnov metric. All models were also stratified by ethnicity and disease stage. Result: In the whole sample (Table 1), older age (b=0.588, p Conclusion: The study results highlight the importance of understanding the role of broader demographic and clinical factors on circulating GFAP levels within diverse cohorts in order to enhance precision across clinical, research, and community settings

Investigating the Heart of a Community: Archaeological Excavations at the African Meeting House, Boston, Massachusetts

In collaboration with the Museum of African American History, an archaeological research team from the University of Massachusetts Boston carried out a data recovery excavation at the African Meeting House on Beacon Hill. The African Meeting House was a powerful social institution for 19thcentury Boston’s free black community. The site played an important role in the abolition movement, the creation of educational opportunity, and other community action for social and political equality. The Meeting House was originally built in 1806, and renovations in preparation for the 2006 bi-centennial celebration prompted an investigation of areas of the property to be impacted by the proposed construction. Archaeological fieldwork, conducted under Massachusetts Historical Commission Permit Number 2750, was spread over seven weeks in May through July 2005. The field team opened and explored about 19 m2 of the site in the backlot south of the Meeting House and alley to the west. These excavations recorded information about a series of significant features and deposits, and collected over 38,000 artifacts and a series of soil samples for a detailed archaeobiological research program. These excavations met the requirements of the data recovery program as outlined in 950 CMR 70.00 and in the Memorandum of Agreement for the project, and the proposed renovation work proceeded with a finding of no adverse effect (36 CFR 800.5(b)). The depositional history and the nature of the archaeological record allow us to separate the overall excavation into three sub-areas: 1) the west alley between the AMH and 2 Smith Court; 2) the historic Meeting House backlot; and 3) the south yard, which originally belonged to the 44 Joy Street property. In terms of significant features and deposits, the west alley was almost entirely a series of builders’ trenches reflecting the historic sequence of construction and remodeling of the Meeting House and adjacent buildings to the west. In the backlot, the units against the south wall of the Meeting House contained similar builders’ trenches. The backlot also contained a series of stone and brick drains and a trash-rich midden layer. The vast majority of artifacts in the Meeting House backlot date from about 1806–1840. The ceramics assemblage is particularly large, and reflects both community meals at the Meeting House and business of Domingo Williams, a caterer who rented a basement apartment. Finally, only one feature was studied in the south yard, a privy (outhouse) that was for the 44 Joy Street property. The bottommost layer of the privy was an artifact rich nightsoil layer, dating to about 1811–1838, and containing the trash of African American tenants living at 44 Joy Street. Together, the archaeological deposits in the backlot provide a variety of insights into living conditions, economic opportunity, foodways, health, and daily life for 19th-century Boston’s free black community. These results thus provide information to help further the research, interpretation, and public education goals of the Museum of African American History

Cognitive performance and normative data between Hispanic and non-Hispanic cohorts: Results from the South Texas Alzheimer’s Disease Research Center (ADRC)

Background: The prevalence of Alzheimer\u27s disease and related dementias (ADRD) in the United States was estimated as 6.5 million people in 2022, with a five-fold increase for the Hispanic/Latinx population expected by 2060. The South Texas Alzheimer\u27s Disease Center (STAC) was designated as a new ADRC in 2021 by the National Institute on Aging (NIA) with a specific aim to serve the growing needs of the local underrepresented Hispanic population. As cultural and linguistic factors can impact performance on cognitive tests, the goal of the study was to compare UDS-3 cognitive test raw scores and normative data in Hispanic and non-Hispanic adults without cognitive impairment residing in South Texas. Method: Participants from the STAC cohort completed the Uniform Data Set (UDS), V.3.0, which includes demographics and neuropsychological battery. All batteries were administered in the participants’ preferred language, English. Normative data was calculated using Weintraub et al. (2018)’s age, sex, and education adjusted regression models for UDSNB 3.0. Mean differences between baseline visit raw scores and normative data were compared using independent sample t-tests among Hispanic and non-Hispanic participants. Result: Thirty-four Hispanic (mean age=70.4, 67.6% female) and thirty-eight non-Hispanic (mean age=71.9, 57.9% female) participants were included. Hispanic participants had fewer years of education relative to non-Hispanic participants [M(SD)] = [14.7(2.5)] to [16.5(2.5)], respectively; (t(70.1)=3.0, p =0.004); although, the groups did not differ in age or sex distribution (p\u3e0.05). Hispanic and non-Hispanic participants generally performed equivalently on the neuropsychological battery. However, Hispanics had lower mean raw scores on the Montreal Cognitive Assessment (MoCA) (t(70.8)= 3.6, p Conclusion: Overall, Hispanic and non-Hispanic participants performed similarly on the UDS-3 neuropsychological battery. However, Hispanics had lower mean raw and normative scores on the MINT, as well as the MoCA which also includes language measures. Our findings highlight the importance of future research validating the sensitivity and specificity of normative data used in underrepresented populations, especially those at higher risk for ADRD

A communal catalogue reveals Earth’s multiscale microbial diversity

Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

A communal catalogue reveals Earth's multiscale microbial diversity

Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe