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Background: The NINDS criteria define Traumatic Encephalopathy Syndrome (TES) as the clinical manifestation of the neuropathologically diagnosed chronic traumatic encephalopathy (CTE). The core clinical features of TES include both cognitive and neuropsychiatric symptoms, the latter termed neurobehavioral dysregulation (NBD). We explored potential biological correlates of NBD by investigating fluid biomarkers of neuronal damage, astrogliosis, phosphorylated tau (pTau), neuroinflammation, and catecholamines in former American football players. Method: Our cohort consisted of former professional (PRO) and college (COL) American football players from the DIAGNOSE CTE Research Project. NBD was measured by four subscales (i.e., explosivity, emotional dyscontrol, impulsivity, affective lability) and a total NBD score, derived by factor analysis of multiple self‐report neuropsychiatric measures. Plasma neurofilament light (NfL) and glial fibrillary acidic protein (GFAP), CSF total tau and pTau181/231/217, as well as CSF biomarkers related to neuroinflammation (IL‐6, CRP, TNF‐α, VEGF‐A), were measured with various well‐validated immunoassay methods. Catecholamines in CSF (dopamine, 3,4‐dihydroxyphenylacetic acid, 3,4‐dihydroxyphenylalanine, noradrenaline, 3,4‐dihydroxyphenylglycol) were measured with HPLC. Multivariate linear regression models assessed the relationships between biomarkers and NBD scales, adjusted for age, BMI, race, and APOE e4, including stratification by exposure group, i.e., PRO, COL. Result: Demographics and biomarker levels are displayed in Table 1. High levels of IL‐6 were significantly associated with higher scores of all NBD subscales, independent of exposure group. Other significant relationships included plasma NfL with emotional dyscontrol and impulsivity. Within the college group, CSF pTau181 was significantly associated with emotional dyscontrol and CSF noradrenaline with explosivity, emotional dyscontrol, impulsivity, and total NBD score. (Table 2 & Figure 1). IL‐6 models were repeated with measures of cognitive dysfunction (another core feature of TES) added as covariates; these analyses again found significant relationships between IL‐6 and NBD, irrespective of cognitive functioning. Conclusion: We observed specific fluid biomarkers related to NBD in former American football players. Of note were the associations between IL‐6 and all NBD subscales (and not with cognitive functioning), suggesting that neuroinflammation may be a specific component in the expression of NBD symptoms. Future studies will investigate how these neuroinflammatory processes are related to other biomarkers, level of RHI exposure, and neuropathology. [ABSTRACT FROM AUTHOR]

Introduction: We examined the association between cerebrospinal fluid (CSF)‐derived biomarkers of Alzheimer's disease and neuropsychiatric symptoms (NPS) in older non‐demented adults. Methods: We included 784 persons (699 cognitively unimpaired, 85 with mild cognitive impairment) aged ≥ 50 years who underwent CSF amyloid beta (Aβ42), hyperphosphorylated tau 181 (p‐tau), and total tau (t‐tau) as well as NPS assessment using Beck Depression and Anxiety Inventories (BDI‐II, BAI), and Neuropsychiatric Inventory Questionnaire (NPI‐Q). Results: Lower CSF Aβ42, and higher t‐tau/Aβ42 and p‐tau/Aβ42 ratios were associated with BDI‐II and BAI total scores, clinical depression (BDI‐II ≥ 13), and clinical anxiety (BAI ≥ 10), as well as NPI‐Q–assessed anxiety, apathy, and nighttime behavior. Discussion: CSF Aβ42, t‐tau/Aβ42, and p‐tau/Aβ42 ratios were associated with NPS in community‐dwelling individuals free of dementia. If confirmed by a longitudinal cohort study, the findings have clinical relevance of taking into account the NPS status of individuals with abnormal CSF biomarkers. [ABSTRACT FROM AUTHOR]

Introduction: We investigated the association of the area deprivation index (ADI) with cognitive decline, mild cognitive impairment (MCI), and dementia in older adults (≥50 years old). ADI is a neighborhood socioeconomic disadvantage measure assessed at the census block group level. Methods: The study included 4699 participants, initially without dementia, with available ADI values for 2015 and at least one study visit in 2008 through 2018. Using logistic regression and Cox proportional hazards models with age as the time scale, we assessed the odds for MCI and the risk for dementia, respectively. Results: In cognitively unimpaired (CU) adults at baseline, the risk for progression to dementia increased for every decile increase in the ADI state ranking (hazard ratio = 1.06, 95% confidence interval (1.01–1.11), P =.01). Higher ADI values were associated with subtly faster cognitive decline. Discussion: In older CU adults, higher baseline neighborhood socioeconomic deprivation levels were associated with progression to dementia and slightly faster cognitive decline. Highlights: The study used area deprivation index, a composite freely available neighborhood deprivation measure.Higher levels of neighborhood deprivation were associated with greater mild cognitive impairment odds.Higher neighborhood deprivation levels were associated with higher dementia risk. [ABSTRACT FROM AUTHOR]

Introduction: We investigated the longitudinal relationship between cortical amyloid deposition, anxiety, and depression and the risk of incident mild cognitive impairment (MCI). Methods: We followed 1440 community‐dwelling, cognitively unimpaired individuals aged ≥ 50 years for a median of 5.5 years. Clinical anxiety and depression were assessed using Beck Anxiety and Depression Inventories (BAI, BDI‐II). Cortical amyloid beta (Aβ) was measured by Pittsburgh compound B positron emission tomography (PiB‐PET) and elevated deposition (PiB+) was defined as standardized uptake value ratio ≥ 1.48. We calculated Cox proportional hazards models with age as the time scale, adjusted for sex, education, and medical comorbidity. Results: Cortical Aβ deposition (PiB+) independent of anxiety (BAI ≥ 10) or depression (BDI‐II ≥ 13) increased the risk of MCI. There was a significant additive interaction between PiB+ and anxiety (joint effect hazard ratio 6.77; 95% confidence interval 3.58–12.79; P =.031) that is, being PiB+ and having anxiety further amplified the risk of MCI. Discussion: Anxiety modified the association between PiB+ and incident MCI. [ABSTRACT FROM AUTHOR]

Apathy is one of the most prevalent, stable and persistent neuropsychiatric symptom across the neurocognitive disorders spectrum. Recent advances in understanding of phenomenology, neurobiology and intervention trials highlight apathy as an important target for clinical intervention. We conducted a comprehensive review and critical evaluation of recent advances to determine the evidence-based suggestions for future trial designs. This review focused on 4 key areas: 1) pre-dementia states; 2) assessment; 3) mechanisms/biomarkers and 4) treatment/intervention efficacy. Considerable progress has been made in understanding apathy as a treatment target and appreciating pharmacological and non-pharmacological apathy treatment interventions. Areas requiring greater investigation include: diagnostic procedures, symptom measurement, understanding the biological mechanisms/biomarkers of apathy, and a well-formed approach to the development of treatment strategies. A better understanding of the subdomains and biological mechanisms of apathy will advance apathy as a treatment target for clinical trials. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) disproportionately affects Mexican Americans, however, reasons underlying this health disparity remain unknown. Type 2 diabetes (T2D) is a risk factor for AD and may contribute to AD pathogenesis. The purpose of this study was to examine the associations between T2D and AD blood biomarkers among Mexican Americans and non‐Hispanic Whites. Methods: This study analyzed baseline data from the Health and Aging Brain Study: Health Disparities (HABS‐HD) that investigated AD differences among Mexican Americans and non‐Hispanic White. HABS‐AD participants were excluded from this study if they had missing data or were outliers (z‐scores >|4|) on a given AD biomarker (N = 1,552 for Aβ42/40 ratio, 1,570 for t‐tau, and 1,553 for NfL). AD biomarkers included plasma Aβ42/42 ratio, total tau (t‐tau), and neurofilament light (NfL) analyzed using Simoa. Predictors were blood glucose, HbA1c, and T2D diagnosis. Data were analyzed with regression analyses controlling for covariates (e.g., demographics, smoking, BMI, health status, diseases, cognition) and treating missing predictor data using Bayesian MCMC estimation. Results: Mexican Americans differed significantly from non‐Hispanic Whites in age (66.6±8.7 vs. 69.5±8.6), sex (64.9% female vs. 55.1%), education (9.5±4.6 vs. 15.6±2.5), blood glucose (113.5±36.6 vs. 99.2±17.0), HbA1c (6.33±1.4 vs. 5.51±0.6), T2D diagnosis (35.3% vs. 11.1%), Aβ42/40 ratio (.051±.012 vs..047±.011), t‐tau (2.56±.95 vs. 2.33±.90), and NfL (16.3±9.5 vs. 20.3±10.3). The models with the covariates and predictors accounted for 6% (p<.001), 15% (p<.001), and 36% (p<.001) of the variation in Aβ42/40 ratio, t‐tau, and NfL, respectively. Blood glucose, HbA1c, and T2D diagnosis were not related to Aβ42/40 ratio and t‐tau but explained 3.7% of the variation in NfL (p<.001). Among non‐Hispanic Whites, blood glucose, HbA1c, and T2D diagnosis were negatively (b = ‐0.09, p<.01, β = ‐0.26), not (b = 0.34, p =.71, β = 0.04), and positively (b = 3.32, p<.01, β = 0.33) associated with NfL, respectively. In contrast, blood glucose and T2D diagnosis were not, while HbA1c was positively (b = 2.31, p<.001, β = 0.26), associated with NfL among Mexican Americans. Conclusion: Blood glucose, HbA1c, and T2D may contribute to differences in NfL levels, but not Aβ42/40 ratio and t‐tau, in an ethnicity‐specific manner. Future studies are needed to corroborate our findings in longitudinal cohorts. [ABSTRACT FROM AUTHOR]

Objective: The authors conducted a prospective cohort study to examine the risk of incident mild cognitive impairment (MCI) as predicted by baseline neuropsychiatric symptoms (NPS) and brain regional glucose metabolic dysfunction.Methods: About 1,363 cognitively unimpaired individuals (52.8% males) aged ≥50 years were followed for a median of 4.8 years to the outcome of incident MCI. NPS were assessed using Beck Depression and Anxiety Inventories and Neuropsychiatric Inventory Questionnaire. Glucose hypometabolism was measured by fluorodeoxyglucose positron emission tomography and defined as standardized uptake value ratio ≤ 1.47 in regions typically affected in Alzheimer disease. Cox proportional hazards models were adjusted for age, sex, education, and APOE ε4 status.Results: Participants with regional glucose hypometabolism and depression (Beck Depression Inventory-II ≥13) had a more than threefold increased risk of incident MCI (hazard ratio [95% confidence interval], 3.66 [1.75, 7.65], p <0.001, χ2 = 11.83, degree of freedom [df] = 1) as compared to the reference group (normal regional glucose metabolism and no depression), and the risk was also significantly elevated (7.21 [3.54, 14.7], p <0.001, χ2 = 29.68, df = 1) for participants with glucose hypometabolism and anxiety (Beck Anxiety Inventory ≥10). Having glucose hypometabolism and ≥1 NPS (3.74 [2.40, 5.82], p <0.001, χ2 = 34.13, df = 1) or ≥2 NPS (3.89 [2.20, 6.86], p <0.001, χ2 = 21.92, df = 1) increased the risk of incident MCI by more than three times, and having ≥3 NPS increased the risk by more than four times (4.12 [2.03, 8.37], p <0.001, χ2 = 15.39, df = 1).Conclusion: Combined presence of NPS with regional glucose hypometabolism is associated with an increased risk of incident MCI, with fluorodeoxyglucose positron emission tomography appearing to be a stronger driving force of cognitive decline than NPS. [ABSTRACT FROM AUTHOR]

Background: Most studies on the relationship between neuropsychiatric symptoms (NPS) and cognitive decline focus on NPS data collected over a short period of time. To better understand the association between NPS and cognitive decline, including their temporal relationship, it is important to know NPS status across a person's life. Method: We utilized the unique Rochester Epidemiology Project medical record linkage system that has captured medical records as far back as 1907, to abstract the psychiatric history of 1810 cognitively unimpaired participants in the population‐based Mayo Clinic Study of Aging (MCSA). Trained nurse abstractors ascertained the presence of exposure to three common NPS (anxiety, depression, and unspecified emotional distress [UED]), both before and after entry into the MCSA. We conducted Cox Proportional Hazards (PH) models using age as the time scale and adjusting for sex, education, and APOE E4 allele for each NPS in predicting mild cognitive impairment (MCI), or dementia. Additional analyses considering medication use (yes/no) and timing of NPS were also run. Result: Anxiety (Hazard Ratio [HR] = 1.47, p<0.001), depression (HR = 1.36, p = 0.001), and UED (HR = 1.22, p = 0.039) were associated with a higher risk of MCI. These associations were present regardless of medication use for anxiety (With medication: HR = 1.51, p<0.001; without medication: HR = 1.41, p = 0.015), and for those taking medications for depression (With medication: HR = 1.47, p<0.001; without medication: 1.09, p = 0.597). Anxiety was associated with MCI regardless of timing of onset with the strongest relationship being for those with onset of anxiety before 65 that persisted into later life (HR = 1.88, p = 0.004). Depression was associated regardless of timing of onset if the depression was present in late life too. The results were similar for the outcome of dementia (Anxiety: HR = 1.62, p<0.001; depression: HR = 1.31, p = 0.040; UED: HR = 1.37, p = 0.014). The associations accounting for medication use and timing of NPS were similar for the outcome of dementia too. Conclusion: NPS is associated with progression to MCI and dementia. Both medication use and timing of NPS might play a role in these associations. [ABSTRACT FROM AUTHOR]

Background: Physical activity is associated with reduced risk for Alzheimer's disease (AD). Aerobic exercise produced modest‐to‐moderate cognitive gains in older adults with mild cognitive impairment or AD dementia. In animal models, aerobic exercise modifies AD's AT(N) biomarkers of Amyloid‐beta (Aβ), hyperphosphorylated Tau, and Neurodegeneration. However, most observational studies didn't find significant associations between physical activity and AT(N) biomarkers. Few exercise trials included biomarkers, partially attributable to the prohibitive cost and invasiveness of cerebrospinal fluid or PET biomarkers and reported mixed effects on central AT(N) biomarkers. Plasma Aβ42/40 ratio, phosphorylated tau 181 (p‐tau181), and total tau (t‐tau) demonstrate robust correlations with central amyloid and tau levels and offer an opportunity for inclusion in exercise trials. Method: This pilot study examined the preliminary effects of 6‐month aerobic exercise on plasma Aβ42/40 ratio, p‐tau181, and t‐tau in older adults with mild‐to‐moderate AD dementia. Twenty‐six participants were eligible, and all consented to enroll (8 in stretching, 18 in cycling). Plasma Aβ42/40 ratio, p‐tau181, and t‐tau were measured using Simoa™ assays at baseline, 3, and 6 months. Data were analyzed using Cohen's d, multilevel model, and intention‐to‐treat. Result: The sample averaged 77.58±6.99 years old, 15.44±3.00 years of education, 65% male, and 96.2% carrying an APOE e4 allele. The 6‐month within‐group trajectories of changes in outcomes trended differently but were not statistically significant. Aβ42/40 ratio (mean ± standard deviation) increased by 0.001±0.012, p‐tau181 increased by 0.609±1.417 pg/ml, and t‐tau decreased by 0.020±0.279 ng/ml in the stretching group, while Aβ42/40 ratio decreased by 0.001±0.010, p‐tau181 increased by 0.101±1.579 pg/ml, and t‐tau decreased by 0.075±0.215 pg/ml in the cycling group. Between‐group differences were not significant. Effect sizes for 6‐month within‐group changes were small except for p‐tau181 in stretching (d = 0.43 [‐.65, 1.45]) and t‐tau in cycling (‐0.35 [‐0.87, 0.17]). Most 6‐month between‐group effect sizes were also small except for p‐tau181 (d =.40 [‐.70, 1.51]) and t‐tau (d =.53 [‐.40, 1.46]), a trend favoring cycling. Conclusion: Blood biomarkers are highly feasible and tolerable. Exercise modalities may affect AD plasma biomarkers differently. Aerobic exercise may reduce p‐tau181 levels and stretching exercise may improve Aβ42/40 ratio, which need to be validated in future trials. [ABSTRACT FROM AUTHOR]

Background: Physical and cognitive activities are associated with decreased risk of mild cognitive impairment and dementia. However, the longitudinal associations between physical and cognitive activities with trajectories of Alzheimer's disease (AD) neuroimaging biomarkers among older adults free of dementia remain unclear. Method: We conducted a longitudinal study derived from the population‐based Mayo Clinic Study of Aging, including individuals aged ≥ 50 years who were free of dementia. Participants had information on physical and cognitive activity engagement in midlife (ages 30‐45 for participants aged 50‐69; ages 50‐65 for participants aged ≥ 70) and late‐life (12 months prior to baseline assessment), and AD biomarker assessments. We calculated linear mixed‐effect models to examine the association between baseline physical and cognitive activity composite scores for mid‐ and late‐life, and trajectories for individual yearly change in amyloid deposition (measured by PiB‐PET), tau burden (measured by Tau‐PET), regional glucose hypometabolism (measured by FDG‐PET), cortical thickness (measured by MRI), and white matter hyper intensities (WMH, measured by FLAIR‐MRI). The models were adjusted for age, sex, and APOE ɛ4 carrier status. Result: The sample included 2755 persons (52% males; 2462 cognitively unimpaired, 293 with MCI). The mean [SD] age was 72.7 [9.8] years; 774 participants were APOE ɛ4 carriers. Although, overall, participants showed an increase in amyloid deposition, tau burden, WMH, and a decrease in glucose metabolism and cortical thickness over time, those with higher late‐life physical activity experienced less pronounced increase in Tau‐PET SUVR over time [estimate for late‐life physical activity with time interaction: ‐0.002; 95% CI ‐0.004, ‐0.000; p = 0.034]. In addition, participants with higher cognitive activities in midlife [est. for midlife cognitive activity with time interaction: 0.001; 95% CI 0.000, 0.003; p = 0.026] and late‐life [est. for late‐life cognitive activity with time interaction 0.002; 95% CI 0.001, 0.003; p = 0.005] had less pronounced decrease in FDG‐PET SUVR over time. There were no further significant interactions. Conclusion: Preliminary findings suggest significant associations between 1) late‐life physical activity and less tauopathy, and 2) cognitive activities in mid‐ and late‐life with less synaptic dysfunction over time. Further research is needed to validate study findings. [ABSTRACT FROM AUTHOR]

Introduction The Mediterranean diet (MeDi) is associated with reduced risk of cognitive impairment, but it is unclear whether it is associated with better brain imaging biomarkers. Methods Among 672 cognitively normal participants (mean age, 79.8 years, 52.5% men), we investigated associations of MeDi score and MeDi components with magnetic resonance imaging measures of cortical thickness for the four lobes separately and averaged (average lobar). Results Higher MeDi score was associated with larger frontal, parietal, occipital, and average lobar cortical thickness. Higher legume and fish intakes were associated with larger cortical thickness: legumes with larger superior parietal, inferior parietal, precuneus, parietal, occipital, lingual, and fish with larger precuneus, superior parietal, posterior cingulate, parietal, and inferior parietal. Higher carbohydrate and sugar intakes were associated with lower entorhinal cortical thickness. Discussion In this sample of elderly persons, higher adherence to MeDi was associated with larger cortical thickness. These cross-sectional findings require validation in prospective studies. [ABSTRACT FROM AUTHOR]

Introduction Apathy is common in neurocognitive disorders (NCDs) such as Alzheimer's disease and mild cognitive impairment. Although the definition of apathy is inconsistent in the literature, apathy is primarily defined as a loss of motivation and decreased interest in daily activities. Methods The Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART) Neuropsychiatric Syndromes Professional Interest Area (NPS-PIA) Apathy workgroup reviewed the latest research regarding apathy in NCDs. Results Progress has recently been made in three areas relevant to apathy: (1) phenomenology, including the use of diagnostic criteria and novel instruments for measurement, (2) neurobiology, including neuroimaging, neuropathological and biomarker correlates, and (3) interventions, including pharmacologic, nonpharmacologic, and noninvasive neuromodulatory approaches. Discussion Recent progress confirms that apathy has a significant impact on those with major NCD and those with mild NCDs. As such, it is an important target for research and intervention. [ABSTRACT FROM AUTHOR]

The article discusses the neuropsychiatric symptoms and neuroimaging biomarkers in Alzheimer Disease.

Abstract: Background: Type 2 diabetes may increase the risk of amnestic mild cognitive impairment (aMCI) through Alzheimer's disease (AD)-related and vascular pathology and may also increase the risk of nonamnestic MCI (naMCI) through vascular disease mechanisms. We examined the association of type 2 diabetes with mild cognitive impairment (MCI) and MCI subtype (aMCI and naMCI) overall and by sex. Methods: Participants were Olmsted County, Minnesota residents (70 years and older) enrolled in a prospective, population-based study. At baseline and every 15 months thereafter, participants were evaluated using the Clinical Dementia Rating scale, a neurological evaluation, and neuropsychological testing for a diagnosis of normal cognition, MCI, and dementia by a consensus panel. Type 2 diabetes was ascertained from the medical records of participants at baseline. Results: Over a median 4.0 years of follow-up, 348 of 1450 subjects developed MCI. Type 2 diabetes was associated (hazard ratio [95% confidence interval]) with MCI (1.39 [1.08–1.79]), aMCI (1.58 [1.17–2.15]; multiple domain: 1.58 [1.01–2.47]; single domain: 1.49 [1.09–2.05]), and the hazard ratio for naMCI was elevated (1.37 [0.84–2.24]). Diabetes was strongly associated with multiple-domain aMCI in men (2.42 [1.31–4.48]) and an elevated risk of multiple domain naMCI in men (2.11 [0.70–6.33]), and with single domain naMCI in women (2.32 [1.04–5.20]). Conclusions: Diabetes was associated with an increased risk of MCI in elderly persons. The association of diabetes with MCI may vary with subtype, number of domains, and sex. Prevention and control of diabetes may reduce the risk of MCI and Alzheimer's disease. [Copyright &y& Elsevier]