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Background and Objective: Patients with dementia with Lewy bodies (DLB) may have overlapping Alzheimer's disease pathology. We investigated the longitudinal rate of tau accumulation and its association with neurodegeneration and clinical disease progression in DLB., Methods: Consecutive patients with probable DLB (n = 22) from the Mayo Clinic Alzheimer's Disease Research Center and age-matched and sex-matched cognitively unimpaired controls (CU; n = 22) with serial magnetic resonance imaging and flortaucipir positron emission tomography scans within an average of 1.6 years were included. Regional annualized rates of flortaucipir uptake standardized uptake value ratios (SUVr) were calculated. Regional annualized rates of cortical volume change were measured with the Tensor Based Morphometry-Syn algorithm., Results: The annual increase of flortaucipir SUVr was greater in the middle and superior occipital, fusiform, and inferior parietal cortices in DLB (mean: 0.017, 0.019, 0.019, and 0.015, respectively) compared with the CU (mean: -0.006, -0.009, -0.003, and - 0.005, respectively; P < 0.05). In patients with DLB (but not the CU), a longitudinal increase in flortaucipir SUVr was associated with longitudinal cortical atrophy rates in the lateral occipital and inferior temporoparietal cortices, hippocampus, and the temporal pole as well as a concurrent decline on Mini-Mental State Examination and Clinical Dementia Rating-Sum of Boxes in the lateral occipital and the fusiform cortices., Conclusions: Tau accumulation was faster in DLB compared with the CU, with increased accumulation rates in the lateral occipital and temporoparietal cortices. These increased rates of tau accumulation were associated with neurodegeneration and faster disease progression in DLB. Tau may be a potential treatment target in a subset of patients with DLB. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society., (© 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.)

Objective: To investigate β-amyloid and tau depositions using Pittsburgh compound B (PiB) positron emission tomography (PET) and AV1451 tau PET imaging in aging multiple sclerosis (MS) patients., Methods: Patients with MS (n = 16) and controls (n = 80) matched for age, sex, and APOE ε4 status from the population-based Mayo Clinic Study of Aging who underwent PiB PET imaging were studied. Of these individuals, 12 patients with MS and 60 matching controls also underwent AV1451 tau PET. Cortical PiB and AV1451 standard uptake value ratios (SUVrs) from the entire cortex and previously determined Alzheimer disease (AD) signature regions in the same population were calculated for group comparisons and testing for associations with age., Results: AD signature PiB SUVr (odds ratio [OR] [95% confidence interval (CI)] = 0.52 [0.27-0.98], p = 0.044), total cortical PiB SUVr (OR [95% CI] = 0.52 [0.28-0.99], p = 0.048), and the frequency of abnormal PiB SUVrs (OR [95% CI] = 0.10 [0.01-0.90], p = 0.040) were lower in MS than controls. Although AD-signature and total cortical AV1451 SUVrs were not different between the groups, the frequency of abnormal AV1451 SUVrs was higher (OR [95% CI] = 10.65 [1.10-103.35], p = 0.041) in MS than controls. The association of AD signature PiB SUVr with age was steeper in the controls compared to patients with MS (estimate [95% CI] = -0.14 [-0.023 to -0.006], p = 0.002). Similarly, the association of total cortical PiB SUVr with age was steeper in the controls compared to patients with MS (estimate [95% CI] = -0.13 [-0.021 to -0.005], p = 0.002). There was no difference in the association of AV1451 SUVr findings with age between the MS patients and controls., Interpretation: Although both β-amyloid and tau are biomarkers of cognitive aging and AD, cortical β-amyloid deposition was lower in MS than age-matched controls, suggesting that some aspect of MS pathobiology retards the accumulation of β-amyloid but not the accumulation of tau. ANN NEUROL 2020;87:556-567., (© 2020 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)

Objective: To investigate the multifactorial processes underlying cognitive aging based on the hypothesis that multiple causal pathways and mechanisms (amyloid, vascular, and resilience) influence longitudinal cognitive decline in each individual through worsening brain health., Methods: We identified 1,230 elderly subjects (aged ≥50 years) with an average of 4.9 years of clinical follow-up and with amyloid positron emission tomography, diffusion tensor imaging, and structural magnetic resonance imaging scans from the population-based Mayo Clinic Study of Aging. We examined imaging markers of amyloid and brain health (white matter microstructural integrity and cortical thinning), systemic vascular health preceding the imaging markers, and early to midlife intellectual enrichment to predict longitudinal cognitive trajectories. We used latent growth curve models for modeling longitudinal cognitive decline., Results: All the pathways (amyloid, vascular, resilience) converged through their effects on cortical thinning and worsening cognition and together explained patterns in cognitive decline. Resilience and vascular pathways (aging process, sex differences, education/occupation, and systemic vascular health) had significant impact on white matter microstructural integrity. Education/occupation levels contributed to white matter integrity through systemic vascular health. Worsening white matter integrity contributed to significant cortical thinning and subsequently longitudinal cognitive decline. Baseline amyloidosis contributed to a significant proportion of cognitive decline that accelerated with longer follow-up times, and its primary impact was through cortical thinning., Interpretation: We developed an integrated framework to help explain the dynamic and complex process of cognitive aging by considering key causal pathways. Such an approach is important for both better comprehension of cognitive aging processes and will aid in the development of successful intervention strategies. ANN NEUROL 2019;86:866-877., (© 2019 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)

Background: Posterior cortical atrophy and dementia with Lewy bodies are 2 distinct clinical syndromes, yet they can overlap in symptoms and occipital hypometabolism. Patients with dementia with Lewy bodies often have overlapping Alzheimer's disease pathology. Similarly, Lewy bodies can be found in patients with posterior cortical atrophy. We investigated differences in the distribution and magnitude of F18-AV-1451 uptake in patients with these 2 syndromes., Methods: Consecutive patients with probable dementia with Lewy bodies (n = 33), posterior cortical atrophy (n = 18), and cognitively unimpaired controls (n = 100) underwent 18 F-AV-1451 positron emission tomography. Regional differences in AV-1451 uptake were assessed using voxel-wise and an atlas-based approach. The greatest differences in AV-1451 uptake between patient groups were identified using area under receiver operating curve statistics, and a composite region was derived., Results: AV-1451 uptake in both patient groups was predominantly localized to the lateral occipital regions, but the magnitude of uptake was markedly greater in posterior cortical atrophy compared with dementia with Lewy bodies. The posterior cortical atrophy group showed the greatest AV-1451 uptake throughout all the gray matter compared with that in other groups. The occipital composite region, consisting of superior, middle, and inferior occipital cortices, distinguished posterior cortical atrophy from dementia with Lewy bodies (area under the curve >0.97; P < 0.001, Bonferroni-corrected) with excellent sensitivity (88%) and specificity (100%)., Conclusions: Posterior cortical atrophy and dementia with Lewy bodies can share clinical features, and although the pattern of AV-1451 uptake in occipital cortices overlaps between these 2 syndromes, its magnitude is significantly higher in posterior cortical atrophy. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society., (© 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.)

Objective: Recent availability of amyloid and tau positron emission tomography (PET) has provided us with a unique opportunity to measure the association of systemic vascular health with brain health after accounting for the impact of Alzheimer disease (AD) pathologies. We wanted to quantify early cerebrovascular health-related magnetic resonance imaging brain measures (structure, perfusion, microstructural integrity) and evaluate their utility as a biomarker for cerebrovascular health., Methods: We used 2 independent samples (discovery, n = 390; validation, n = 1,035) of individuals, aged ≥ 60 years, along the cognitive continuum with imaging from the population-based sample of Mayo Clinic Study of Aging. We ascertained vascular health by summing up recently existing cardiovascular and metabolic conditions (CMC) from health care records (hypertension, hyperlipidemia, cardiac arrhythmias, coronary artery disease, congestive heart failure, diabetes mellitus, and stroke). Using multiple regression models, we quantified associations between CMC and brain health after accounting for age, sex, education/occupation, and AD burden (from amyloid and tau PET)., Results: Systemic vascular health was associated with medial temporal lobe thinning, widespread cerebral hypoperfusion, and loss of microstructural integrity in several white matter tracts including the corpus callosum and fornix. Further investigations suggested that microstructural integrity of the genu of the corpus callosum was suitable for assessing prodromal cerebrovascular health, had similar distributions in the discovery and independent validation datasets, and predicted cognitive performance above and beyond amyloid deposition., Interpretation: Systemic vascular health has significant impact on brain structure and function. Quantifying prodromal cerebrovascular health-related brain measures that are independent of AD pathology-related changes has great utility for cognitive aging. Ann Neurol 2018;84:713-724., (© 2018 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)

Objective: To investigate the associations between age, vascular health, and Alzheimer disease (AD) imaging biomarkers in an elderly sample., Methods: We identified 430 individuals along the cognitive continuum aged >60 years with amyloid positron emission tomography (PET), tau PET, and magnetic resonance imaging (MRI) scans from the population-based Mayo Clinic Study of Aging. A subset of 329 individuals had fluorodeoxyglucose (FDG) PET. We ascertained presently existing cardiovascular and metabolic conditions (CMC) from health care records and used the summation of presence/absence of hypertension, hyperlipidemia, cardiac arrhythmias, coronary artery disease, congestive heart failure, diabetes mellitus, and stroke as a surrogate for vascular health. We used global amyloid from Pittsburgh compound B PET, entorhinal cortex tau uptake (ERC-tau) from tau-PET, and neurodegeneration in AD signature regions from MRI and FDG-PET as surrogates for AD pathophysiology. We dichotomized participants into CMC = 0 (CMC - ) versus CMC > 0 (CMC + ) and tested for age-adjusted group differences in AD biomarkers. Using structural equation models (SEMs), we assessed the impact of vascular health on AD biomarker cascade (amyloid leads to tau leads to neurodegeneration) after considering the direct and indirect age, sex, and apolipoprotein E effects., Results: CMC + participants had significantly greater neurodegeneration than CMC - participants but did not differ by amyloid or ERC-tau. The SEMs showed that (1) vascular health had a significant direct and indirect impact on neurodegeneration but not on amyloid; and (2) vascular health, specifically the presence of hyperlipidemia, had a significant direct impact on ERC-tau., Interpretation: Vascular health had quantifiably greater impact on neurodegeneration in AD regions than on amyloid deposition. Longitudinal studies are warranted to clarify the relationship between tau deposition and vascular health. Ann Neurol 2017;82:706-718., (© 2017 American Neurological Association.)

Background: The clinical course of dementia with Lewy bodies patients is heterogeneous. The ability to more accurately prognosticate survival is important., Objective: The objective of this study was to investigate hippocampal volume as a predictor of survival in dementia with Lewy bodies patients., Methods: Survival analysis for time from onset of cognitive symptoms to death was carried out using Cox proportional hazards models. Given their age and total intracranial volume, patients were dichotomized into low/medium (0%-66.7%) and high (66. 7%-100%) hippocampal volume categories. The models using these categories to predict survival were adjusted for field strength, APOE ε4 status, and estimated onset age of cognitive problems., Results: We investigated 167 consecutive patients with dementia with Lewy bodies. The median age at MRI was 72 years (interquartile range 67-76), and 80% were male. The median time from estimated first cognitive symptom to death was 7.4 years (interquartile range:5.7-10.2). Lower hippocampal volumes were significantly associated with higher risk of death (hazard ratio 1.28; 95% confidence interval 1.04-1.58; P = .024). The predicted median survival for participants with onset of cognitive symptoms at age 68 was 10.63 years (95% confidence interval 8.66-14.54) for APOE ε4 negative, high hippocampal volume participants; 8.89 years (95% confidence interval 7.56-12.36) for APOE ε4 positive, high hippocampal volume participants; 8.10 years (95% confidence interval 7.34-11.08) for APOE ε4 negative, low/medium hippocampal volume participants; and 7.38 (95% confidence interval 6.74-9.29) years for APOE ε4 positive, low/medium hippocampal volume participants., Conclusions: Among patients with clinically diagnosed dementia with Lewy bodies, those with neuroimaging evidence of hippocampal atrophy have shorter survival times. © 2016 International Parkinson and Movement Disorder Society., (© 2016 International Parkinson and Movement Disorder Society.)

Objective: A study was undertaken to investigate the association of intellectual and physical activity with biomarkers of Alzheimer disease (AD) pathophysiology and cognition in a nondemented elderly population. The biomarkers evaluated were brain Aβ load via Pittsburgh compound B (PiB)-positron emission tomography (PET), neuronal dysfunction via (18) F-fluorodeoxyglucose (FDG)-PET, and neurodegeneration via structural magnetic resonance imaging (MRI)., Methods: We studied 515 nondemented (428 cognitively normal and 87 mild cognitive impairment) participants in the population-based Mayo Clinic Study of Aging who completed a 3T MRI, PET scans, and APOE genotype, and had lifestyle activity measures and cognition data available. The imaging measures computed were global PiB-PET uptake, and global FDG-PET and MRI based hippocampal volume. We consolidated activity variables into lifetime intellectual, current intellectual, and current physical activities. We used a global cognitive z score as a measure of cognition. We applied 2 independent methods-partial correlation analysis adjusted for age and gender and path analysis using structural equations-to evaluate the associations between lifestyle activities, imaging biomarkers, and global cognition., Results: None of the lifestyle variables were correlated with the biomarkers, and the path associations between lifestyle variables and biomarkers were not significant (p > 0.05). Conversely, all the biomarkers were correlated with global cognitive z score (p < 0.05), and the path associations between (lifetime and current) intellectual activities and global z score were significant (p < 0.01)., Interpretation: Intellectual and physical activity lifestyle factors were not associated with AD biomarkers, but intellectual lifestyle factors explained variability in the cognitive performance in this nondemented population. This study provides evidence that lifestyle activities may delay the onset of dementia but do not significantly influence the expression of AD pathophysiology., (Copyright © 2012 American Neurological Association.)