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Previous studies have identified bilingualism as a protective factor against dementia. Here we aimed to test whether being bilingual at different life stages impacts cognition and brain structure in older adulthood. We included 746 participants from the DZNE-Longitudinal Cognitive Impairment and Dementia Study (DELCODE). Assessment of bilingualism at 3 life stages (early: 13-30, middle: 30-65 and late: over 65 years old) was determined with the Lifetime of Experiences Questionnaire. Individuals reporting bilingualism (i.e., daily use of L2) in the early life stage outperformed monolinguals on learning & memory, working-memory, executive functions and language. Bilingualism in middle life stage showed a significant advantage on learning & memory, while no effect of bilingualism in old life stage was identified. Brain gray matter volume was not associated with L2 use and did not differ between groups. However, stronger correlations between brain gray matter volume in selected brain regions and cognitive performance were found in bilingual participants in the early and middle life stages. Our results indicate that bilingualism in early life might provide a long-lasting protective effect on cognition and shape the brain to sustain cognitive performance in older adulthood.

It remains unknown whether the global small vessel disease (SVD) burden predicts post-stroke outcomes.In a prospective multicenter study of 666 ischemic and hemorrhagic stroke patients, we quantified magnetic resonance imaging (MRI)-based SVD markers (lacunes, white matter hyperintensities, microbleeds, perivascular spaces) and explored associations with 6- and 12-month cognitive (battery of 15 neuropsychological tests) and functional (modified Rankin scale) outcomes.A global SVD score (range 0-4) was associated with cognitive impairment; worse performance in executive function, attention, language, and visuospatial ability; and worse functional outcome across a 12-month follow-up. Although the global SVD score did not improve prediction, individual SVD markers, assessed across their severity range, improved the calibration, discrimination, and reclassification of predictive models including demographic, clinical, and other imaging factors.SVD presence and severity are associated with worse cognitive and functional outcomes 12 months after stroke. Assessing SVD severity may aid prognostication for stroke patients.In a multi-center cohort, we explored associations of small vessel disease (SVD) burden with stroke outcomes. SVD burden associates with post-stroke cognitive and functional outcomes. A currently used score of SVD burden does not improve the prediction of poor outcomes. Assessing the severity of SVD lesions adds predictive value beyond known predictors. To add predictive value in assessing SVD in stroke patients, SVD burden scores should integrate lesion severity.

Background and ObjectivesWe assessed whether novelty-related fMRI activity in medial temporal lobe regions and the precuneus follows an inverted U-shaped pattern across the clinical spectrum of increased Alzheimer disease (AD) risk as previously suggested. Specifically, we tested for potentially increased activity in individuals with a higher AD risk due to subjective cognitive decline (SCD) or mild cognitive impairment (MCI). We further tested whether activity differences related to diagnostic groups were accounted for by CSF markers of AD or brain atrophy.MethodsWe studied 499 participants aged 60–88 years from the German Center for Neurodegenerative Diseases Longitudinal Cognitive Impairment and Dementia Study (DELCODE) who underwent task-fMRI. Participants included 163 cognitively normal (healthy control, HC) individuals, 222 SCD, 82 MCI, and 32 patients with clinical diagnosis of mild AD. CSF levels of β-amyloid 42/40 ratio and phosphorylated-tau181 were available from 232 participants. We used region-based analyses to assess novelty-related activity (novel > highly familiar scenes) in entorhinal cortex, hippocampus, and precuneus as well as whole-brain voxel-wise analyses. First, general linear models tested differences in fMRI activity between participant groups. Complementary regression models tested quadratic relationships between memory impairment and activity. Second, relationships of activity with AD CSF biomarkers and brain volume were analyzed. Analyses were controlled for age, sex, study site, and education.ResultsIn the precuneus, we observed an inverted U-shaped pattern of novelty-related activity across groups, with higher activity in SCD and MCI compared with HC, but not in patients with AD who showed relatively lower activity than MCI. This nonlinear pattern was confirmed by a quadratic relationship between memory impairment and precuneus activity. Precuneus activity was not related to AD biomarkers or brain volume. In contrast to the precuneus, hippocampal activity was reduced in AD dementia compared with all other groups and related to AD biomarkers.DiscussionNovelty-related activity in the precuneus follows a nonlinear pattern across the clinical spectrum of increased AD risk. Although the underlying mechanism remains unclear, increased precuneus activity might represent an early signature of memory impairment. Our results highlight the nonlinearity of activity alterations that should be considered in clinical trials using functional outcome measures or targeting hyperactivity.

INTRODUCTION: It remains unclear whether functional brain networks are consistently altered in individuals with subjective cognitive decline (SCD) of diverse ethnic and cultural backgrounds and whether the network alterations are associated with an amyloid burden.METHODS: Cross-sectional resting-state functional magnetic resonance imaging connectivity (FC) and amyloid-positron emission tomography (PET) data from the Chinese Sino Longitudinal Study on Cognitive Decline and German DZNE Longitudinal Cognitive Impairment and Dementia cohorts were analyzed.RESULTS: Limbic FC, particularly hippocampal connectivity with right insula, was consistently higher in SCD than in controls, and correlated with SCD-plus features. Smaller SCD subcohorts with PET showed inconsistent amyloid positivity rates and FC-amyloid associations across cohorts.DISCUSSION: Our results suggest an early adaptation of the limbic network in SCD, which may reflect increased awareness of cognitive decline, irrespective of amyloid pathology. Different amyloid positivity rates may indicate a heterogeneous underlying etiology in Eastern and Western SCD cohorts when applying current research criteria. Future studies should identify culture-specific features to enrich preclinical Alzheimer's disease in non-Western populations.HIGHLIGHTS: Common limbic hyperconnectivity across Chinese and German subjective cognitive decline (SCD) cohorts was observed. Limbic hyperconnectivity may reflect awareness of cognition, irrespective of amyloid load. Further cross-cultural harmonization of SCD regarding Alzheimer's disease pathology is required.

BACKGROUND: The NIA-AA proposed amyloid-tau-neurodegeneration (ATN) as a classification system for AD biomarkers. The amyloid cascade hypothesis (ACH) implies a sequence across ATN groups that patients might undergo during transition from healthy towards AD: A-T-N-➔A+T-N-➔A+T+N-➔A+T+N+. Here we assess the evidence for monotonic brain volume decline for this particular (amyloid-conversion first, tau-conversion second, N-conversion last) and alternative progressions using voxel-based morphometry (VBM) in a large cross-sectional MRI cohort.METHODS: We used baseline data of the DELCODE cohort of 437 subjects (127 controls, 168 SCD, 87 MCI, 55 AD patients) which underwent lumbar puncture, MRI scanning, and neuropsychological assessment. ATN classification was performed using CSF-Aβ42/Aβ40 (A+/-), CSF phospho-tau (T+/-), and adjusted hippocampal volume or CSF total-tau (N+/-). We compared voxel-wise model evidence for monotonic decline of gray matter volume across various sequences over ATN groups using the Bayesian Information Criterion (including also ROIs of Braak stages). First, face validity of the ACH transition sequence A-T-N-➔A+T-N-➔A+T+N-➔A+T+N+ was compared against biologically less plausible (permuted) sequences among AD continuum ATN groups. Second, we evaluated evidence for 6 monotonic brain volume progressions from A-T-N- towards A+T+N+ including also non-AD continuum ATN groups.RESULTS: The ACH-based progression A-T-N-➔A+T-N-➔A+T+N-➔A+T+N+ was consistent with cognitive decline and clinical diagnosis. Using hippocampal volume for operationalization of neurodegeneration (N), ACH was most evident in 9% of gray matter predominantly in the medial temporal lobe. Many cortical regions suggested alternative non-monotonic volume progressions over ACH progression groups, which is compatible with an early amyloid-related tissue expansion or sampling effects, e.g., due to brain reserve. Volume decline in 65% of gray matter was consistent with a progression where A status converts before T or N status (i.e., ACH/ANT) when compared to alternative sequences (TAN/TNA/NAT/NTA). Brain regions earlier affected by tau tangle deposition (Braak stage I-IV, MTL, limbic system) present stronger evidence for volume decline than late Braak stage ROIs (V/VI, cortical regions). Similar findings were observed when using CSF total-tau for N instead.CONCLUSION: Using the ATN classification system, early amyloid status conversion (before tau and neurodegeneration) is associated with brain volume loss observed during AD progression. The ATN system and the ACH are compatible with monotonic progression of MTL atrophy.TRIAL REGISTRATION: DRKS00007966, 04/05/2015, retrospectively registered.

Background In preclinical Alzheimer’s disease, it is unclear why some individuals with amyloid pathologic change are asymptomatic (stage 1), whereas others experience subjective cognitive decline (SCD, stage 2). Here, we examined the association of stage 1 vs. stage 2 with structural brain reserve in memory-related brain regions. Methods We tested whether the volumes of hippocampal subfields and parahippocampal regions were larger in individuals at stage 1 compared to asymptomatic amyloid-negative older adults (healthy controls, HCs). We also tested whether individuals with stage 2 would show the opposite pattern, namely smaller brain volumes than in amyloid-negative individuals with SCD. Participants with cerebrospinal fluid (CSF) biomarker data and bilateral volumetric MRI data from the observational, multi-centric DZNE-Longitudinal Cognitive Impairment and Dementia Study (DELCODE) study were included. The sample comprised 95 amyloid-negative and 26 amyloid-positive asymptomatic participants as well as 104 amyloid-negative and 47 amyloid-positive individuals with SCD. Volumes were based on high-resolution T2-weighted images and automatic segmentation with manual correction according to a recently established high-resolution segmentation protocol. Results In asymptomatic individuals, brain volumes of hippocampal subfields and of the parahippocampal cortex were numerically larger in stage 1 compared to HCs, whereas the opposite was the case in individuals with SCD. MANOVAs with volumes as dependent data and age, sex, years of education, and DELCODE site as covariates showed a significant interaction between diagnosis (asymptomatic versus SCD) and amyloid status (Aß42/40 negative versus positive) for hippocampal subfields. Post hoc paired comparisons taking into account the same covariates showed that dentate gyrus and CA1 volumes in SCD were significantly smaller in amyloid-positive than negative individuals. In contrast, CA1 volumes were significantly (p = 0.014) larger in stage 1 compared with HCs. Conclusions These data indicate that HCs and stages 1 and 2 do not correspond to linear brain volume reduction. Instead, stage 1 is associated with larger than expected volumes of hippocampal subfields in the face of amyloid pathology. This indicates a brain reserve mechanism in stage 1 that enables individuals with amyloid pathologic change to be cognitively normal and asymptomatic without subjective cognitive decline.

The original version of this Article omitted from the author list the 212th author Patrizia Mecocci, who is from the Institute of Gerontology and Geriatrics, Department of Medicine, University of Perugia, Perugia, Italy. Consequently, the “Sample Contribution” section of Author Contributions was updated to add “P.M” between “P.D.” and “R.C.”. Additionally, the original version of this Article contained the incorrect affiliation for author Patrick Gavin Kehoe, which incorrectly read “German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany”. The correct version replaces this affiliation with “Bristol Medical School (THS), University of Bristol, Southmead Hospital, Bristol, UK”. This has been corrected in both the PDF and HTML versions of the Article. CA extern

BackgroundWhite matter hyperintensities (WMH), a biomarker of small vessel disease, are often found in Alzheimer’s disease (AD) and their advanced detection and quantification can be beneficial for research and clinical applications. To investigate WMH in large-scale multicenter studies on cognitive impairment and AD, appropriate automated WMH segmentation algorithms are required. This study aimed to compare the performance of segmentation tools and provide information on their application in multicenter research.MethodsWe used a pseudo-randomly selected dataset (n = 50) from the DZNE-multicenter observational Longitudinal Cognitive Impairment and Dementia Study (DELCODE) that included 3D fluid-attenuated inversion recovery (FLAIR) images from participants across the cognitive continuum. Performances of top-rated algorithms for automated WMH segmentation [Brain Intensity Abnormality Classification Algorithm (BIANCA), lesion segmentation toolbox (LST), lesion growth algorithm (LGA), LST lesion prediction algorithm (LPA), pgs, and sysu_media] were compared to manual reference segmentation (RS).ResultsAcross tools, segmentation performance was moderate for global WMH volume and number of detected lesions. After retraining on a DELCODE subset, the deep learning algorithm sysu_media showed the highest performances with an average Dice’s coefficient of 0.702 (±0.109 SD) for volume and a mean F1-score of 0.642 (±0.109 SD) for the number of lesions. The intra-class correlation was excellent for all algorithms (>0.9) but BIANCA (0.835). Performance improved with high WMH burden and varied across brain regions.ConclusionTo conclude, the deep learning algorithm, when retrained, performed well in the multicenter context. Nevertheless, the performance was close to traditional methods. We provide methodological recommendations for future studies using automated WMH segmentation to quantify and assess WMH along the continuum of cognitive impairment and AD dementia.

Background: Cognitive reserve (CR) explains inter-individual differences in the impact of the neurodegenerative burden on cognitive functioning. A residual model was proposed to estimate CR more accurately than previous measures. However, associations between residual CR markers (CRM) and functional connectivity (FC) remain unexplored. Objective: To explore the associations between the CRM and intrinsic network connectivity (INC) in resting-state networks along the neuropathological-continuum of Alzheimer’s disease (ADN). Methods: Three hundred eighteen participants from the DELCODE cohort were stratified using cerebrospinal fluid biomarkers according to the A(myloid-β)/T(au)/N(eurodegeneration) classification. CRM was calculated utilizing residuals obtained from a multilinear regression model predicting cognition from markers of disease burden. Using an independent component analysis in resting-state fMRI data, we measured INC of resting-state networks, i.e., default mode network (DMN), frontoparietal network (FPN), salience network (SAL), and dorsal attention network. The associations of INC with a composite memory score and CRM and the associations of CRM with the seed-to-voxel functional connectivity of memory-related were tested in general linear models. Results: CRM was positively associated with INC in the DMN in the entire cohort. The A+T+N+ group revealed an anti-correlation between the SAL and the DMN. Furthermore, CRM was positively associated with anti-correlation between memory-related regions in FPN and DMN in ADN and A+T/N+. Conclusion: Our results provide evidence that INC is associated with CRM in ADN defined as participants with amyloid pathology with or without cognitive symptoms, suggesting that the neural correlates of CR are mirrored in network FC in resting-state.

Background: It is unclear whether subjective cognitive decline (SCD) is a relevant clinical marker of incipient Alzheimer’s disease (AD) and future cognitive deterioration in individuals with a family history of AD (FHAD). Objective: To investigate the association of SCD with cross-sectional cerebrospinal fluid (CSF) AD biomarker levels and cognitive decline in cognitively normal older adults with or without a first-degree FHAD. Methods: We analyzed data from cognitively normal individuals with first-degree FHAD (n = 82 “AD relatives”; mean age: 65.7 years (SD = 4.47); 59% female) and a similar group of n = 236 healthy controls without FHAD from the DELCODE study. We measured SCD with an in-depth structured interview from which we derived a SCD score, capturing features proposed to increase likelihood of underlying AD (“SCD-plus score”). We tested whether higher SCD-plus scores were associated with more pathological CSF AD biomarker levels and cognitive decline over time and whether this association varied by group. Results: AD relatives showed higher SCD-plus scores than healthy controls and more cognitive decline over time. Higher SCD-plus scores also related stronger to cognitive change and abnormal CSF AD biomarker levels in the AD relatives as compared to the healthy controls group. Conclusion: Quantification of specific SCD features can provide further information on the likelihood of early AD pathology and cognitive decline among AD relatives. FHAD and SCD appear as synergistically acting enrichment strategies in AD research, the first one as a permanent indicator of genetic risk, the latter one as a correlate of disease progression.

Background: Parkinson’s disease (PD) is associated with various non-motor symptoms, including cognitive deterioration. Objective: Here, we used data from the DEMPARK/LANDSCAPE cohort to describe the association between progression of cognitive profiles and the PD motor phenotypes: postural instability and gait disorder (PIGD), tremor-dominant (TR-D), and not-determined (ND). Methods: Demographic, clinical, and neuropsychological six-year longitudinal data of 711 PD-patients were included (age: M = 67.57; 67.4% males). We computed z-transformed composite scores for a priori defined cognitive domains. Analyses were controlled for age, gender, education, and disease duration. To minimize missing data and drop-outs, three-year follow-up data of 442 PD-patients was assessed with regard to the specific role of motor phenotype on cognitive decline using linear mixed modelling (age: M = 66.10; 68.6% males). Results: Our study showed that in the course of the disease motor symptoms increased while MMSE and PANDA remained stable in all subgroups. After three-year follow-up, significant decline of overall cognitive performance for PIGD-patients were present and we found differences for motor phenotypes in attention (β= –0.08, SE = 0.003, p

While some individuals age without pathological memory impairments, others develop age‐associated cognitive diseases. Since changes in cognitive function develop slowly over time in these patients, they are often diagnosed at an advanced stage of molecular pathology, a time point when causative treatments fail. Thus, there is great need for the identification of inexpensive and minimal invasive approaches that could be used for screening with the aim to identify individuals at risk for cognitive decline that can then undergo further diagnostics and eventually stratified therapies. In this study, we use an integrative approach combining the analysis of human data and mechanistic studies in model systems to identify a circulating 3‐microRNA signature that reflects key processes linked to neural homeostasis and inform about cognitive status. We furthermore provide evidence that expression changes in this signature represent multiple mechanisms deregulated in the aging and diseased brain and are a suitable target for RNA therapeutics., Alzheimer’s disease (AD) is usually diagnosed at an advanced stage of molecular pathology, a time point when causative treatments fail. This study aimed to identify a minimally invasive biomarker that can help to identify individuals at risk for cognitive decline before clinical manifestation.

Additional file 5: Supplementary Figure 3. Comparison of mean relevance maps between samples.

Additional file 2: Supplementary Table 2. Group separation performance for hippocampus volume and the convolutional neural network models for raw input data.

Additional file 6: Supplementary Figure 4. Correlation matrix of hippocampus volume (residualized) and several brain regions’ relevance scores for DELCODE participants and the model trained on the whole ADNI-GO/2 dataset.

Additional file 3: Supplementary Figure 1. UML diagram of the interactive visualization application.

BackgroundThe Locus Coeruleus (LC) may play an important role in the pathogenesis of Alzheimer’s disease (AD). Neuromelanin-sensitive Magnetic Resonance Imaging (MRI) permits the visualization of the LC in vivo. Previously, we proposed an automatic, deep learning-based approach to segmenting the LC in a cohort of 82 healthy young and older adults (82 HC; Dünnwald et al. 2021). Here, we applied the same automatic segmentation method to baseline data from the DZNE Longitudinal Cognitive Impairment and Dementia (DELCODE) study comprising 42 healthy elderly adults (HEA), 18 participants with subjective cognitive decline (SCD), 25 participants with mild cognitive impairment (MCI) and 11 participants with AD.MethodThe LC was visualized using 3T T1-weighted Fast Low Angle Shot (FLASH) MRI acquired at 0.75mm isotropic resolution. Prior to processing, the data was sinc-interpolated to a resolution of 0.375mm³. The automated segmentation pipeline comprises two consecutive Convolutional Neural Networks (CNNs), which perform LC centerpoint regression and segmentation (see Fig. 1). The networks were trained only on the 82 HC dataset using a cross-validation scheme. We applied the networks to the unseen DELCODE data and assessed their performance with respect to manually delineated masks from two trained raters using Dice similarity coefficient (DSC) and intraclass correlation coefficient (ICC) of contrast ratios (CRs).ResultIn HEA, the networks showed similar agreement (DSC, ICC) compared to that observed between two independent raters. Using DSC, automated segmentation of SCD, MCI and AD groups showed less agreement than in the HEA group with 66.67%, 64.86%, 59.77% and 67.06% on average respectively (see Fig. 2). However, good reliability between automated and manually delineated masks for all groups using LC MRI contrast was observed (see Tab. 1) indicating that CRs may be relatively robust wrt. mask differences (see Fig. 3 and 4 for qualitative comparisons).ConclusionThe results demonstrate good reliability between manual and automatically generated LC segmentations with respect to LC MRI contrast using networks trained on healthy older adults. Additional fine-tuning of the networks to account for the variance in AD should be explored as a means to further improve reliability.

Additional file 1: Supplementary Table 1. Group separation performance for hippocampus volume and the convolutional neural network models for residualized data (extended).

Additional file 4: Supplementary Figure 2. Sequence diagram of function calls when selecting a new person.

Author(s): Piot, Ines; Schweyer, Kerstin; Respondek, Gesine; Stamelou, Maria; DescribePSP study group; ProPSP study group; MDS-endorsed PSP study group; Sckopke, Philipp; Schenk, Thomas; Goetz, Christopher G; Stebbins, Glenn T; Hoglinger, Gunter U | Abstract: BackgroundThere is currently no undisputed, validated, clinically meaningful measure for deficits in the broad spectrum of PSP phenotypes.ObjectiveTo develop a scale to monitor clinical deficits in patients with PSP across its broad phenotypes.MethodsThe Progressive Supranuclear Palsy Clinical Deficits Scale was conceptualized to cover seven clinical domains (Akinesia-rigidity, Bradyphrenia, Communication, Dysphagia, Eye movements, Finger dexterity, and Gait a balance), each scored from 0 to 3 (no, mild, moderate, or severe deficits). User guidelines were developed to standardize its application. Progressive Supranuclear Palsy Clinical Deficits Scale scores were collected in patients fulfilling the MDS-PSP diagnostic criteria in two independent, multicenter, observational studies, both cross-sectionally (exploratory DescribePSP cohort; confirmatory ProPSP cohort) and longitudinally (12-months' follow-up, both cohorts).ResultsCognitive pretesting demonstrated easy scale utility. In total, 164 patients were scored (70.4 ± 7.6 years; 62% males, 35% variant phenotypes). Mean Progressive Supranuclear Palsy Clinical Deficits Scale completion time was 4 minutes. The Progressive Supranuclear Palsy Clinical Deficits Scale total score correlated with existing scales (e.g., Progressive Supranuclear Palsy Rating Scale: R = 0.88; P l 0.001). Individual Progressive Supranuclear Palsy Clinical Deficits Scale items correlated well with similar constructs in existing scales. Internal consistency (Cronbach's alpha: 0.75), inter-rater reliability (0.96), and test-retest stability (0.99) were acceptable. The PSP-CDS showed significant 12-month change (baseline, 8.6 ± 3.6; follow-up: 10.8 ± 3.6; annualized difference: 3.4 ± 3.4; n = 49; P l 0.0001). Sample sizes required per arm for a two-arm, 1-year follow-up therapeutic trial to detect 50% change in Progressive Supranuclear Palsy Clinical Deficits Scale progression was estimated to be 65 (two-sided, two-sample t test).ConclusionThe Progressive Supranuclear Palsy Clinical Deficits Scale is a rapidly completed, clinimetrically sound scale for clinical care and research involving PSP. © 2020 International Parkinson and Movement Disorder Society.

Additional file 1: Table S1. Results from binary logistic regression to predict a GDS total score ≥ 1 (A) and ≥ 2 (B). Table S2. Results from binary logistic regression to predict a GAI-SF total score ≥ 1 (A) and ≥ 2 (B). Table S3. Results from binary logistic regression to predict the presence of agitation, depression, anxiety, apathy, irritability and sleep disturbances on the NPI-Q.

Alien limb phenomenon is a rare syndrome associated with a feeling of non-belonging and disowning toward one's limb. In contrast, anarchic limb phenomenon leads to involuntary but goal-directed movements. Alien/anarchic limb phenomena are frequent in corticobasal syndrome (CBS), an atypical parkinsonian syndrome characterized by rigidity, akinesia, dystonia, cortical sensory deficit, and apraxia. The structure–function relationship of alien/anarchic limb was investigated in multi-centric structural magnetic resonance imaging (MRI) data. Whole-group and single-subject comparisons were made in 25 CBS and eight CBS-alien/anarchic limb patients versus controls. Support vector machine was used to see if CBS with and without alien/anarchic limb could be distinguished by structural MRI patterns. Whole-group comparison of CBS versus controls revealed asymmetric frontotemporal atrophy. CBS with alien/anarchic limb syndrome versus controls showed frontoparietal atrophy including the supplementary motor area contralateral to the side of the affected limb. Exploratory analysis identified frontotemporal regions encompassing the pre-/and postcentral gyrus as compromised in CBS with alien limb syndrome. Classification of CBS patients yielded accuracies of 79%. CBS-alien/anarchic limb syndrome was differentiated from CBS patients with an accuracy of 81%. Predictive differences were found in the cingulate gyrus spreading to frontomedian cortex, postcentral gyrus, and temporoparietoocipital regions. We present the first MRI-based group analysis on CBS-alien/anarchic limb. Results pave the way for individual clinical syndrome prediction and allow understanding the underlying neurocognitive architecture.

C9ORF72 mutations are the most common cause of familial frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). MRI studies have investigated structural changes in C9ORF72-associated FTLD (C9FTLD) and provided first insights about a prominent involvement of the thalamus and the cerebellum. Our multicenter, 18F-fluorodeoxyglucose positron-emission tomography study of 22 mutation carriers with FTLD, 22 matched non-carriers with FTLD, and 23 cognitively healthy controls provided valuable insights into functional changes in C9FTLD: compared to non-carriers, mutation carriers showed a significant reduction of glucose metabolism in both thalami, underscoring the key role of the thalamus in C9FTLD. Thalamic metabolism did not correlate with disease severity, duration of disease, or the presence of psychotic symptoms. Against our expectations we could not demonstrate a cerebellar hypometabolism in carriers or non-carriers. Future imaging and neuropathological studies in large patient cohorts are required to further elucidate the central role of the thalamus in C9FTLD.

Introduction: Subjective cognitive decline (SCD) in cognitively unimpaired older individuals has been recognized as an early clinical at-risk state for Alzheimer's disease (AD) dementia and as a target population for future dementia prevention trials. Currently, however, SCD is heterogeneously defined across studies, potentially leading to variations in the prevalence of AD pathology. Here, we compared the prevalence and identified common determinants of abnormal AD biomarkers in SCD across three European memory clinics participating in the European initiative on harmonization of SCD in preclinical AD (Euro-SCD). Methods: We included three memory clinic SCD samples with available cerebrospinal fluid (CSF) biomaterial (IDIBAPS, Barcelona, Spain, n = 44; Amsterdam Dementia Cohort (ADC), The Netherlands, n = 50; DELCODE multicenter study, Germany, n = 42). CSF biomarkers (amyloid beta (Aβ)42, tau, and phosphorylated tau (ptau181)) were centrally analyzed in Amsterdam using prespecified cutoffs to define prevalence of pathological biomarker concentrations. We used logistic regression analysis in the combined sample across the three centers to investigate center effects with regard to likelihood of biomarker abnormality while taking potential common predictors (e.g., age, sex, apolipoprotein E (APOE) status, subtle cognitive deficits, depressive symptoms) into account. Results: The prevalence of abnormal Aβ42, but not tau or ptau181, levels was different across centers (64% DELCODE, 57% IDIBAPS, 22% ADC; p < 0.001). Logistic regression analysis revealed that the likelihood of abnormal Aβ42 (and also abnormal tau or ptau181) levels was predicted by age and APOE status. For Aβ42 abnormality, we additionally observed a center effect, indicating between-center heterogeneity not explained by age, APOE, or the other included covariates. Conclusions: While heterogeneous frequency of abnormal Aβ42 was partly explained by between-sample differences in age range and APOE status, the additional observation of center effects indicates between-center heterogeneity that may be attributed to different recruitment procedures. These findings highlight the need for the development of harmonized recruitment protocols for SCD case definition in multinational studies to achieve similar enrichment rates of preclinical AD.

Subjective Cognitive Decline Interview (SCD-I). Table S1. Linear regression with the number of fulfilled SCD-plus features predicting AD biomarkers. Table S2. Linear regression with the number of reported SCD-I domains predicting AD biomarkers. (PDF 137 kb)

Table S1. Antibody subclasses, number of NMDAab positive samples and titres in PD patients, controls and PD diagnostic subgroups. (DOCX 14 kb)

Background With upcoming therapeutic interventions for patients with primary progressive aphasia (PPA), instruments for the follow-up of patients are needed to describe disease progression and to evaluate potential therapeutic effects. So far, volumetric brain changes have been proposed as clinical endpoints in the literature, but cognitive scores are still lacking. This study followed disease progression predominantly in language-based performance within 1 year and defined a PPA sum score which can be used in therapeutic interventions. Methods We assessed 28 patients with nonfluent variant PPA, 17 with semantic variant PPA, 13 with logopenic variant PPA, and 28 healthy controls in detail for 1 year. The most informative neuropsychological assessments were combined to a sum score, and associations between brain atrophy were investigated followed by a sample size calculation for clinical trials. Results Significant absolute changes up to 20% in cognitive tests were found after 1 year. Semantic and phonemic word fluency, Boston Naming Test, Digit Span, Token Test, AAT Written language, and Cookie Test were identified as the best markers for disease progression. These tasks provide the basis of a new PPA sum score. Assuming a therapeutic effect of 50% reduction in cognitive decline for sample size calculations, a number of 56 cases is needed to find a significant treatment effect. Correlations between cognitive decline and atrophy showed a correlation up to r = 0.7 between the sum score and frontal structures, namely the superior and inferior frontal gyrus, as well as with left-sided subcortical structures. Conclusion Our findings support the high performance of the proposed sum score in the follow-up of PPA and recommend it as an outcome measure in intervention studies.

Previous studies have demonstrated increased tau plasma levels in patients with Alzheimer’s disease (AD) and mild cognitive impairment (MCI) due to AD. Much less is known whether increased tau plasma levels can already be detected in the pre-MCI stage of subjective cognitive decline (SCD). In the present study we measured tau plasma levels in 111 SCD patients and 134 age- and gender-matched cognitively healthy controls participating in the DZNE (German Center for Neurodegenerative Diseases) longitudinal study on cognition and dementia (DELCODE). Tau plasma levels were measured using ultra-sensitive, single-molecule array (Simoa) technology. We found no significant different tau plasma levels in SCD (3.4 pg/ml) compared with healthy controls (3.6 pg/ml) after controlling for age, gender, and education (p = 0.137). In addition, tau plasma levels did not correlate with Aβ42 (r = 0.073; p = 0.634), tau (r = −0.179; p = 0.240), and p-tau181 (r = −0.208; p = 0.171) cerebrospinal fluid (CSF) levels in a subgroup of 45 SCD patients with available CSF. In conclusion, plasma tau is not increased in SCD patients. In addition, the lack of correlation between tau in plasma and CSF in the examined cohort suggests that tau levels are affected by different factors in both biofluids.

Background and Objective: Altered levels of naturally occurring autoantibodies (nAbs) against disease-associated neuronal proteins have been reported for neurodegenerative diseases, such as Alzheimer's (AD) and Parkinson's disease (PD). Recent histopathologic studies suggest a contribution of both Lewy body- and AD-related pathology to Parkinson's disease dementia (PDD). Therefore, we explored nAbs against alpha-synuclein (αS), tau and β-amyloid (Aβ) in PDD compared to cognitively normal PD patients. Materials and Methods: We established three different ELISAs to quantify the nAbs-tau, nAbs-αS, and nAbs-Aβ levels and avidity towards their specific antigen in serum samples of 18 non-demented (PDND) and 18 demented PD patients (PDD), which were taken from an ongoing multi-center cohort study (DEMPARK/LANDSCAPE). Results: PDD patients had significantly decreased nAbs-tau serum levels compared to PDND patients (p = 0.007), whereas the serum titers of nAbs-αS and nAbs-Aβ were unchanged. For all three nAbs, no significant differences in avidity were found between PDD and PDND cohorts. However, within both patient groups, nAbs-tau showed lowest avidity to their antigen, followed by nAbs-αS, and nAbs-Aβ. Though, due to a high interassay coefficient of variability and the exclusion of many samples below the limit of detection, conclusions for nAbs-Aβ are only conditionally possible. Conclusion: We detected a significantly decreased nAbs-tau serum level in PDD patients, indicating a potential linkage between nAbs-tau serum titer and cognitive deficits in PD. Thus, further investigation in larger samples is justified to confirm our findings. OA gold

Objective: To identify biological evidence for Alzheimer disease (AD) in individuals with subjective memory impairment (SMI) and unimpaired cognitive performance and to investigate the longitudinal cognitive course in these subjects. Method: [ 18 F]fluoro-2-deoxyglucose PET (FDG-PET) and structural MRI were acquired in 31 subjects with SMI and 56 controls. Cognitive follow-up testing was performed (average follow-up time: 35 months). Differences in baseline brain imaging data and in memory decline were assessed between both groups. Associations of memory decline with brain imaging data were tested. Results: The SMI group showed hypometabolism in the right precuneus and hypermetabolism in the right medial temporal lobe. Gray matter volume was reduced in the right hippocampus in the SMI group. At follow-up, subjects with SMI showed a poorer performance than controls on measures of episodic memory. Longitudinal memory decline in the SMI group was associated with reduced glucose metabolism in the right precuneus at baseline. Conclusion: The cross-sectional difference in 2 independent neuroimaging modalities indicates early AD pathology in SMI. The poorer memory performance at follow-up and the association of reduced longitudinal memory performance with hypometabolism in the precuneus at baseline support the concept of SMI as the earliest manifestation of AD.

Introduction: There is a growing need for prospective observationalstudies linking ICU parameters and serum biomarkers to long-termcognitive, brain morphological and other functional outcomes amongsurvivors of sepsis.Objectives: The main goal of this DZNE-sponsored study is to provide a comprehensive long-term cognitive, neurological, brainmorphological, electroencephalographic and serological profile ofsevere sepsis and septic shock survivors. The need for rehabilitationmeasures after successful survival of the initial disease will be thoroughly evaluated in terms of neurological status, changes in dailyactivities and function level, sleep and psychiatric burden

The aim of the study was to investigate the efficacy of the antibiotic minocycline as a drug treatment in patients with Multiple-System-Atrophy Parkinson-type (MSA-P). Sixty-three patients were randomized to minocycline 200 mg/d (n = 32) or a matching placebo (n = 31). The primary outcome variable was the change in the value of the motor score of the Unified Multiple-System-Atrophy Rating-Scale (UMSARSII) from baseline to 48 weeks. Secondary outcome variables included subscores and individual Parkinsonian symptoms as determined by the UMSARS and the Unified-Parkinson's-Disease Rating-Scale (UPDRS). Health-related quality of life (HrQoL) was assessed using the EQ-5D and SF-12. "Progression rate" was assumed to be reflected in the change in motor function over 48 weeks. At 24 weeks and 48 weeks of follow-up, there was a significant deterioration in motor scores in both groups, but neither the change in UMSARSII nor in UPDRSIII differed significantly between treatment groups, i.e. "progression rate" was considered to be similar in both treatment arms. HrQoL did not differ among the two treatment arms. In a small subgroup of patients (n = 8; minocycline = 3, placebo = 5)[(11)C](R)-PK11195-PET was performed. The three patients in the minocycline group had an attenuated mean increase in microglial activation as compared to the placebo group (P = 0.07) and in two of them individually showed decreased [11C](R)-PK11195 binding actually decreased. These preliminary PET-data suggest that minocycline may interfere with microglial activation. The relevance of this observation requires further investigation. This prospective, 48 week, randomized, double-blind, multinational study failed to show a clinical effect of minocycline on symptom severity as assessed by clinical motor function.

Background: Parkinson’s disease (PD) is often accompanied by non-motor complications, such as dementia, depression, and psychotic symptoms, which worsen the prognosis and increase the personal and socioeconomic burden of disease. Prevalence estimates of these complications are quite variable and are lacking for the outpatient care sector. Methods: As part of a larger, nationwide, cross-sectional epidemiological study in n=315 neurological outpatient settings in Germany, this paper estimates the frequency of dementia and cognitive impairment in n=873 outpatients meeting the UK Brain Bank criteria for idiopathic PD. Assessments were based on a clinical interview and neuropsychological assessments, including the Hoehn & Yahr rating and Unified Parkinson’s Disease Rating Scale (UPDRS). Cognitive impairment was assessed by the Mini-Mental State Exam (MMSE), Clock Drawing Test (CDT) and the Parkinson Neuropsychometric Dementia Assessment (PANDA) and the clinician’s diagnosis of dementia was based on the diagnostic criteria of DSMIV. Results Using standardized cutoff scores, the prevalence of cognitive impairment in the study sample as measured by various methods was 17.5% by MMSE (≤ 24), 41.8% by CDT (≥ 3), 43.6% by PANDA (≤ 14), and 28.6% met the DSM-IV criteria for dementia. All estimates increased with age and PD severity. Gender was an inconsistent contributor while illness duration had no significant impact on cognition. Multiple regression analyses revealed PD severity to be the strongest predictor of dementia risk (OR=4.3; 95 % CI: 2.1–9.1), while neuropsychiatric syndromes had independent, although modest additional contributions (OR=2.5, 95% CI: 1.6–3.8). Conclusion: Estimates of cognitive impairment and dementia in PD patients are largely dependent on the diagnostic measure used. Using established clinical diagnostic standards for dementia the overall rate on routine outpatient neurological care is 28.6%, but using more sensitive neuropsychological measures, rates for cognitive impairment might be up to 2-fold higher. The MMSE revealed strikingly low sensitivity. Neuropsychiatric syndromes, in addition to PD severity and age, have an independent – although modest – additional contribution to patients’ risk for cognitive impairment and dementia.

ObjectiveTo determine the association of serum neurofilament light chain (NfL) with functional deterioration and brain atrophy during follow-up of patients with behavioral variant frontotemporal dementia (bvFTD).MethodsBlood NfL levels from 74 patients with bvFTD, 26 with Alzheimer disease (AD), 17 with mild cognitive impairment (MCI), and 15 healthy controls (Con) at baseline and follow-up were determined and analyzed for the diagnostic potential in relation to functional assessment (Clinical Dementia Rating Scale Sum of Boxes [CDR-SOB], frontotemporal lobar degeneration–related CDR-SOB, Mini-Mental State Examination [MMSE]) and brain volumetry.ResultsAt baseline, serum NfL level correlated with CSF NfL (bvFTD r = 0.706, p < 0.0001; AD/MCI r = 0.666, p = 0.0003). Highest serum levels were observed in bvFTD (p p = 0.0078 vs AD, respectively). Discrimination of bvFTD from Con/MCI/AD was possible with 91%/74%/74% sensitivity and 79%/74%/58% specificity. At follow-up, serum NfL increased in bvFTD and AD (p = 0.0039 and p = 0.0006, respectively). At baseline and follow-up, NfL correlated with functional scores of patients with bvFTD (e.g., CDR-SOB [baseline] r = 0.4157, p = 0.0006; [follow-up] r = 0.5629, p < 0.0001) and with atrophy in the gray and white matter of many brain regions including frontal and subcortical areas (e.g., frontal lobe: r = −0.5857, p < 0.0001; 95% confidence interval −0.7415 to −0.3701). For patients with AD/MCI, NfL correlated with the functional performance as well (e.g., CDR-SOB [baseline] r = 0.6624, p < 0.0001; [follow-up] r = 0.5659, p = 0.0003) but not with regional brain volumes.ConclusionsAs serum NfL correlates with functional impairment and brain atrophy in bvFTD at different disease stages, we propose it as marker of disease severity, paving the way for its future use as outcome measure for clinical trials.Classification of evidenceThis study provides Class III evidence that for patients with cognitive problems, serum NfL concentration discriminates bvFTD from other forms of dementia.

Funder: Funder: Fundación bancaria ‘La Caixa’ Number: LCF/PR/PR16/51110003 Funder: Grifols SA Number: LCF/PR/PR16/51110003 Funder: European Union/EFPIA Innovative Medicines Initiative Joint Number: 115975 Funder: JPco-fuND FP-829-029 Number: 733051061, Genetic discoveries of Alzheimer's disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer's disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer's disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer's disease.

Background: Deep phenotyping and longitudinal assessment of predementia at- risk states of Alzheimer’s disease (AD) are required to define populations and outcomes for dementia prevention trials. Subjective cognitive decline (SCD) is a pre-mild cognitive impairment (pre-MCI) at-risk state of dementia, which emerges as a highly promising target for AD prevention. Methods: The German Center for Neurodegenerative Diseases (DZNE) is conducting the multicenter DZNE-Longitudinal Cognitive Impairment and Dementia Study (DELCODE), which focuses on the characterization of SCD in patients recruited from memory clinics. In addition, individuals with amnestic MCI, mild Alzheimer’s dementia patients, first-degree relatives of patients with Alzheimer’s dementia, and cognitively unimpaired control subjects are studied. The total number of subjects to be enrolled is 1000. Participants receive extensive clinical and neuropsychological assessments, magnetic resonance imaging, positron emission tomography, and biomaterial collection is perfomed. In this publication, we report cognitive and clinical data as well as apolipoprotein E (APOE) genotype and cerebrospinal fluid (CSF) biomarker results of the first 394 baseline data sets. Results: In comparison with the control group, patients with SCD showed slightly poorer performance on cognitive and functional measures (Alzheimer’s Disease Assessment Scale—cognitive part, Clinical Dementia Rating, Functional Activities Questionnaire), with all mean scores in a range which would be considered unimpaired. APOE4 genotype was enriched in the SCD group in comparison to what would be expected in the population and the frequency was significantly higher in comparison to the control group. CSF Aβ42 was lower in the SCD group in comparison to the control group at a statistical trend with age as a covariate. There were no group differences in Tau or pTau concentrations between the SCD and the control groups. The differences in all measures between the MCI group and the AD group were as expected. Conclusions: The initial baseline data for DELCODE support the approach of using SCD in patients recruited through memory clinics as an enrichment strategy for late- stage preclinical AD. This is indicated by slightly lower performance in a range of measures in SCD in comparison to the control subjects as well as by enriched APOE4 frequency and lower CSF Aβ42 concentration.

Alzheimer’s disease (AD) is a severe and incurable neurodegenerative disease, and the failure to find effective treatments suggests that the underlying pathology remains poorly understood. Due to its strong heritability, deciphering the genetic landscape of AD and related dementia (ADD) is a unique opportunity to advance our knowledge. We completed a meta-analysis of genome-wide association studies (39,106 clinically AD-diagnosed cases, 46,828 proxy-ADD cases and 401,577 controls) with the most promising signals followed-up in 25,392 independent AD cases and 276,086 controls. We report 75 risk loci for ADD, including 42 novel ones. Pathway-enrichment analyses confirm the involvement of amyloid/Tau pathways, highlight the role of microglia and its potential interaction with APP metabolism. Numerous genes exhibited differential expression or splicing in AD-related conditions and gene prioritization implies EGFR signaling and TNF-α pathway through LUBAC complex. We also generated a novel polygenic risk score strongly associated with the risk of future dementia or progression from mild cognitive impairment to dementia. In conclusion, by more than doubling the number of loci associated with ADD risk, our study offers new insights into the pathophysiological processes underlying AD and offers additional therapeutic entry-points and tools for translational genomics.