Dispersion-based cognitive intra-individual variability in former American football players: Association with traumatic encephalopathy syndrome, repetitive head impacts, and biomarkers.

Exposure to repetitive head impacts (RHI), such as those experienced in American football, is linked to cognitive dysfunction later in life. Traumatic encephalopathy syndrome (TES) is a proposed clinical syndrome thought to be linked to neuropath-ology of chronic traumatic encephalopathy (CTE), a condition associated with RHI from football. Cognitive intra-individual variability (d-CIIV) measures test-score dispersion, indicating cognitive dysfunction.

Single- versus two-test criteria for cognitive impairment: associations with CSF and imaging markers in former American football players.

 Cognitive impairment is a core feature of traumatic encephalopathy syndrome (TES), the putative clinical syndrome of chronic traumatic encephalopathy-a neuropathological disease associated with repetitive head impacts (RHI). Careful operationalization of cognitive impairment is essential to improving the diagnostic specificity and accuracy of TES criteria. We compared single- versus two-test criteria for cognitive impairment in their associations with CSF and imaging biomarkers in male former American football players.

Olfactory function is reduced in a subset of former elite American football players with traumatic encephalopathy syndrome.

Former American football players are at risk for developing traumatic encephalopathy syndrome (TES), the clinical disorder associated with neuropathologically diagnosed chronic traumatic encephalopathy (CTE). The objective of this study was to determine whether hyposmia is present in traumatic encephalopathy syndrome. The study included 119 former professional American football players, 60 former college football players, and 58 same-age asymptomatic unexposed men from the DIAGNOSE CTE Research Project.

Clinical and Neuropathological Correlates of Substance Use in American Football Players.

Background: Chronic traumatic encephalopathy (CTE) is a neurodegenerative tauopathy more frequently found in deceased former football players. CTE has heterogeneous clinical presentations with multifactorial causes. Previous literature has shown substance use (alcohol/drug) can contribute to Alzheimer's disease and related tauopathies pathologically and clinically.

Optimal blood tau species for the detection of Alzheimer's disease neuropathology: an immunoprecipitation mass spectrometry and autopsy study.

Plasma-to-autopsy studies are essential for validation of blood biomarkers and understanding their relation to Alzheimer's disease (AD) pathology. Few such studies have been done on phosphorylated tau (p-tau) and those that exist have made limited or no comparison of the different p-tau variants. This study is the first to use immunoprecipitation mass spectrometry (IP-MS) to compare the accuracy of eight different plasma tau species in predicting autopsy-confirmed AD.

Amyloid PET across the cognitive spectrum in former professional and college American football players: findings from the DIAGNOSE CTE Research Project.

Background: Exposure to repetitive head impacts (RHI) in American football players can lead to cognitive impairment and dementia due to neurodegenerative disease, particularly chronic traumatic encephalopathy (CTE). The pathognomonic lesion of CTE consists of perivascular aggregates of hyper-phosphorylated tau in neurons at the depths of cortical sulci. However, it is unclear whether exposure to RHI accelerates amyloid-β (Aβ) plaque formation and increases the risk for Alzheimer's disease (AD).

Neuropsychological test performance of former American football players.

Background: Patterns of cognitive impairment in former American football players are uncertain because objective neuropsychological data are lacking. This study characterized the neuropsychological test performance of former college and professional football players.

Methods: One hundred seventy male former football players (n=111 professional, n=59 college; 45-74 years) completed a neuropsychological test battery.

Associations between near end-of-life flortaucipir PET and postmortem CTE-related tau neuropathology in six former American football players.

Purpose: Flourine-18-flortaucipir tau positron emission tomography (PET) was developed for the detection for Alzheimer's disease. Human imaging studies have begun to investigate its use in chronic traumatic encephalopathy (CTE). Flortaucipir-PET to autopsy correlation studies in CTE are needed for diagnostic validation.

White matter hyperintensities in former American football players.

Introduction: The presentation, risk factors, and etiologies of white matter hyperintensities (WMH) in people exposed to repetitive head impacts are unknown. We examined the burden and distribution of WMH, and their association with years of play, age of first exposure, and clinical function in former American football players.

Methods: A total of 149 former football players and 53 asymptomatic unexposed participants (all men, 45-74 years) completed fluid-attenuated inversion recovery magnetic resonance imaging, neuropsychological testing, and self-report neuropsychiatric measures.

Association of APOE Genotypes and Chronic Traumatic Encephalopathy.

Importance: Repetitive head impact (RHI) exposure is the chief risk factor for chronic traumatic encephalopathy (CTE). However, the occurrence and severity of CTE varies widely among those with similar RHI exposure. Limited evidence suggests that the APOEε4 allele may confer risk for CTE, but previous studies were small with limited scope.

Ante-mortem plasma phosphorylated tau (181) predicts Alzheimer's disease neuropathology and regional tau at autopsy.

Blood-based biomarkers such as tau phosphorylated at threonine 181 (phosphorylated-tau181) represent an accessible, cost-effective and scalable approach for the in vivo detection of Alzheimer's disease pathophysiology. Plasma-pathological correlation studies are needed to validate plasma phosphorylated-tau181 as an accurate and reliable biomarker of Alzheimer's disease neuropathological changes. This plasma-to-autopsy correlation study included participants from the Boston University Alzheimer's Disease Research Center who had a plasma sample analysed for phosphorylated-tau181 between 2008 and 2018 and donated their brain for neuropathological examination.

Association of Playing College American Football With Long-term Health Outcomes and Mortality.

Importance: Exposure to repetitive head impacts from playing American football (including impacts resulting in symptomatic concussions and subconcussive trauma) is associated with increased risk for later-life health problems, including cognitive and neuropsychiatric decline and neurodegenerative disease. Most research on long-term health consequences of playing football has focused on former professional athletes, with limited studies of former college players.

Objectives: To estimate the prevalence of self-reported health conditions among former college football players compared with a sample of men in the general population as well as standardized mortality ratios (SMRs) among former college football players.

Plasma p-tau shows stronger network association to Alzheimer's disease dementia than neurofilament light and total tau.

Introduction: We examined the ability of plasma hyperphosphorylated tau (p-tau) to detect cognitive impairment due to Alzheimer's disease (AD) independently and in combination with plasma total tau (t-tau) and neurofilament light (NfL).

Methods: Plasma samples were analyzed using the Simoa platform for 235 participants with normal cognition (NC), 181 with mild cognitive impairment due to AD (MCI), and 153 with AD dementia. Statistical approaches included multinomial regression and Gaussian graphical models (GGMs) to assess a network of plasma biomarkers, neuropsychological tests, and demographic variables.

Comprehensive, School-Based Preventive Dentistry: Program Details and Students' Unmet Dental Needs.

Background: In this paper, we describe the design, program details, and baseline demographics and oral health of participants in ForsythKids, a regional, comprehensive, school-based mobile caries prevention program.

Methods: We solicited all Massachusetts elementary schools with greater than 50% of students receiving free or reduced-price meals. Six schools initially elected to participate, ultimately followed by over 50 schools.

Association of Bariatric Surgery With Vascular Outcomes.

Importance: Bariatric surgical weight loss is associated with reduced cardiovascular mortality; however, the mechanisms underlying this association are incompletely understood.

Objectives: To identify variables associated with vascular remodeling after bariatric surgery and to examine how sex, race, and metabolic status are associated with microvascular and macrovascular outcomes.

Design, Setting, And Participants: This population-based longitudinal cohort included 307 individuals who underwent bariatric surgery.

Validity of the 2014 traumatic encephalopathy syndrome criteria for CTE pathology.

Introduction: Validity of the 2014 traumatic encephalopathy syndrome (TES) criteria, proposed to diagnose chronic traumatic encephalopathy (CTE) in life, has not been assessed.

Methods: A total of 336 consecutive brain donors exposed to repetitive head impacts from contact sports, military service, and/or physical violence were included. Blinded to clinical information, neuropathologists applied National Institute on Neurological Disorders and Stroke/National Institute of Biomedical Imaging and Bioengineering CTE criteria.