Search

Objective: Amyotrophic lateral sclerosis (ALS) is a clinically heterogenous disease, typically presenting with focal motor weakness that eventually generalizes. Weather there is a correlation between focal motor weakness and metabolic alterations in specific areas of the brain has not been thoroughly explored. This study aims to systematically investigate this by using fluorodeoxyglucose-positron emission tomography (FDG-PET), including longitudinal imaging. Methods: This observational imaging study included 131 ALS patients diagnosed and examined with FDG-PET at the ALS Clinical Research Center at the Karolinska University Hospital in Stockholm, Sweden. Thirteen ALS patients had a second scan and were analyzed longitudinally. The findings were compared to 39 healthy controls examined at the University Medical Center of Gröningen, the Netherlands. Results: There was a general pattern of brain metabolic alterations consistent with previously reported findings in ALS, namely hypometabolism in frontal regions and hypermetabolism in posterior regions. A higher symptom burden was associated with increased hypometabolism and decreased hypermetabolism. However, there was no clear correlation between focal motor weakness and specific metabolic alterations, neither when analyzing focal motor weakness with concomitant upper motor neuron signs or when including all focal motor weakness. Longitudinal FDG-PET imaging showed inconsistent results with little correlation between progression of motor weakness and metabolic alterations. Conclusion: Our results support the disease model of ALS as a diffuse process since no clear correlation was seen between focal motor weakness and specific metabolic alterations. However, there is need for further research on a larger number of patients, particularly including longitudinal imaging.

ImportanceIndividuals who are amyloid-positive with subjective cognitive decline and clinical features increasing the likelihood of preclinical Alzheimer disease (SCD+) are at higher risk of developing dementia. Some individuals with SCD+ undergo amyloid-positron emission tomography (PET) as part of research studies and frequently wish to know their amyloid status; however, the disclosure of a positive amyloid-PET result might have psychological risks.ObjectiveTo assess the psychological outcomes of the amyloid-PET result disclosure in individuals with SCD+ and explore which variables are associated with a safer disclosure in individuals who are amyloid positive.Design, Setting, and ParticipantsThis prospective, multicenter study was conducted as part of The Amyloid Imaging to Prevent Alzheimer Disease Diagnostic and Patient Management Study (AMYPAD-DPMS) (recruitment period: from April 2018 to October 2020). The setting was 5 European memory clinics, and participants included patients with SCD+ who underwent amyloid-PET. Statistical analysis was performed from July to October 2022.ExposuresDisclosure of amyloid-PET result.Main Outcomes and MeasuresPsychological outcomes were defined as (1) disclosure related distress, assessed using the Impact of Event Scale–Revised (IES-R; scores of at least 33 indicate probable presence of posttraumatic stress disorder [PTSD]); and (2) anxiety and depression, assessed using the Hospital Anxiety and Depression scale (HADS; scores of at least 15 indicate probable presence of severe mood disorder symptoms).ResultsAfter disclosure, 27 patients with amyloid-positive SCD+ (median [IQR] age, 70 [66-74] years; gender: 14 men [52%]; median [IQR] education: 15 [13 to 17] years, median [IQR] Mini-Mental State Examination [MMSE] score, 29 [28 to 30]) had higher median (IQR) IES-R total score (10 [2 to 14] vs 0 [0 to 2]; P P P P P = .06) and Depression (–1.0 [–2.0 to 0.0] vs –1.0 [–3.0 to 0.0]; P = .46) deltas (score after disclosure – scores at baseline). In patients with amyloid-positive SCD+, despite the small sample size, higher education was associated with lower disclosure-related distress (ρ = –0.43; P = .02) whereas the presence of study partner was associated with higher disclosure-related distress (W = 7.5; P = .03). No participants with amyloid-positive SCD+ showed probable presence of PTSD or severe anxiety or depression symptoms at follow-up.Conclusions and RelevanceThe disclosure of a positive amyloid-PET result to patients with SCD+ was associated with a bigger psychological change, yet such change did not reach the threshold for clinical concern.

Amyloid positron emission tomography (PET) allows the direct assessment of amyloid deposition, one of the main hallmarks of Alzheimer disease. However, this technique is currently not widely reimbursed because of the lack of appropriately designed studies demonstrating its clinical effect.To assess the clinical effect of amyloid PET in memory clinic patients.The AMYPAD-DPMS is a prospective randomized clinical trial in 8 European memory clinics. Participants were allocated (using a minimization method) to 3 study groups based on the performance of amyloid PET: arm 1, early in the diagnostic workup (within 1 month); arm 2, late in the diagnostic workup (after a mean [SD] 8 [2] months); or arm 3, if and when the managing physician chose. Participants were patients with subjective cognitive decline plus (SCD+; SCD plus clinical features increasing the likelihood of preclinical Alzheimer disease), mild cognitive impairment (MCI), or dementia; they were assessed at baseline and after 3 months. Recruitment took place between April 16, 2018, and October 30, 2020. Data analysis was performed from July 2022 to January 2023.Amyloid PET.The main outcome was the difference between arm 1 and arm 2 in the proportion of participants receiving an etiological diagnosis with a very high confidence (ie, ≥90% on a 50%-100% visual numeric scale) after 3 months.A total of 844 participants were screened, and 840 were enrolled (291 in arm 1, 271 in arm 2, 278 in arm 3). Baseline and 3-month visit data were available for 272 participants in arm 1 and 260 in arm 2 (median [IQR] age: 71 [65-77] and 71 [65-77] years; 150/272 male [55%] and 135/260 male [52%]; 122/272 female [45%] and 125/260 female [48%]; median [IQR] education: 12 [10-15] and 13 [10-16] years, respectively). After 3 months, 109 of 272 participants (40%) in arm 1 had a diagnosis with very high confidence vs 30 of 260 (11%) in arm 2 (P < .001). This was consistent across cognitive stages (SCD+: 25/84 [30%] vs 5/78 [6%]; P < .001; MCI: 45/108 [42%] vs 9/102 [9%]; P < .001; dementia: 39/80 [49%] vs 16/80 [20%]; P < .001).In this study, early amyloid PET allowed memory clinic patients to receive an etiological diagnosis with very high confidence after only 3 months compared with patients who had not undergone amyloid PET. These findings support the implementation of amyloid PET early in the diagnostic workup of memory clinic patients.EudraCT Number: 2017-002527-21.

Cross-sectional studies have indicated potential for positron emission tomography (PET) in imaging tau pathology in Alzheimer’s disease (AD); however, its prognostic utility remains unproven. In a longitudinal, multi-modal, prognostic study of cognitive decline, 20 patients with a clinical biomarker-based diagnosis in the AD spectrum (mild cognitive impairment or dementia and a positive amyloid-beta PET scan) were recruited from the Cognitive Clinic at Karolinska University Hospital. The participants underwent baseline neuropsychological assessment, PET imaging with [18F]THK5317, [11C]PIB and [18F]FDG, magnetic resonance imaging, and in a subgroup cerebrospinal fluid (CSF) sampling, with clinical follow-up after a median 48 months (interquartile range = 32:56). In total, 11 patients declined cognitively over time, while 9 remained cognitively stable. The accuracy of baseline [18F]THK5317 binding in temporal areas was excellent at predicting future cognitive decline (area under the receiver operating curve 0.84–1.00) and the biomarker levels were strongly associated with the rate of cognitive decline (β estimate −33.67 to −31.02, p 0.05). Baseline [18F]THK5317 binding and CSF tau levels were more strongly associated with the MMSE score at follow-up than at baseline (p

Data de publicació electrónica: 17-06-2022 Introduction: AMYPAD Diagnostic and Patient Management Study (DPMS) aims to investigate the clinical utility and cost-effectiveness of amyloid-PET in Europe. Here we present participants' baseline features and discuss the representativeness of the cohort. Methods: participants with subjective cognitive decline plus (SCD+), mild cognitive impairment (MCI), or dementia were recruited in eight European memory clinics from April 16, 2018, to October 30, 2020, and randomized into three arms: ARM1, early amyloid-PET; ARM2, late amyloid-PET; and ARM3, free-choice. Results: A total of 840 participants (244 SCD+, 341 MCI, and 255 dementia) were enrolled. Sociodemographic/clinical features did not differ significantly among recruiting memory clinics or with previously reported cohorts. The randomization assigned 35% of participants to ARM1, 32% to ARM2, and 33% to ARM3; cognitive stages were distributed equally across the arms. Discussion: the features of AMYPAD-DPMS participants are as expected for a memory clinic population. This ensures the generalizability of future study results. This communication reflects the views of the authors and neither the Innovative Medicines Initiative (IMI) nor the European Union and the European Federation of Pharmaceutical Industries and Associations (EFPIA) are liable for any use that may be made of the information contained herein. The Geneva Memory Center is funded by the following private donors under the supervision of the Private Foundation of Geneva University Hospitals: A.P.R.A. - Association Suisse pour la Recherche sur la Maladie d'Alzheimer, Genève; Fondation Segré, Genève; Ivan Pictet, Genève; Fondazione Agusta, Lugano; Fondation Chmielewski, Genève. Competitive research projects have been funded by: H2020, Human Brain Project, Innovative Medicines Initiative (IMI), IMI2, Swiss National Science Foundation, VELUX Foundation. External sites affiliated with CHUT: Françoise Desclaux (Geriatrics department of Lavaur), Marie-Noelle Cufi (Geriatrics department of Lavaur), and Jérémie Pariente (department of Neurology of Toulouse University Hospital, Inserm Toulouse NeuroImaging Center, Université Paul Sabatier, Centre d'Investigation Clinique de Toulouse CIC 1436). The BBRC's memory center received funding from the Barcelona City Council (agreement # 20XC0354) and Biogen. Daniele Altomare received funding from the Fondation Recherche Alzheimer and the Swiss National Science Foundation (project CRSK-3_196354/1). Camilla Caprioglio was supported by EU-EFPIA Innovative Medicines Initiatives 2 Joint Undertaking (IMI 2 JU) Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD, grant agreement number: 115952). Johannes Berkhof is a recipient of ABOARD, which is a public-private partnership receiving funding from ZonMW (#73305095007) and Health∼Holland, Topsector Life Sciences & Health (PPP-allowance; #LSHM20106), and received funding from the EU (AMYPAD, RISCC), ZonMW (HPV compare), WHO, IARC, and RIVM. Valentina Garibotto was supported by the Swiss National Science Foundation (projects 320030_169876, 320030_185028 and IZSEZ0_188355), by the Velux Foundation (project 1123), by the Schmidheiny foundation, and by the Aetas foundation. Oriol Grau-Rivera received funding from Alzheimer's Association (2019-AARF-644568) and Instituto de Salud Carlos III (PI19/00117). Juan Domingo Gispert is supported by the Spanish Ministry of Science and Innovation (RYC-2013-13054) and received funding from the EU-EFPIA Innovative Medicines Initiatives 2 Joint Undertaking (IMI 2 JU) Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD, grant agreement number: 115952). Alexander Drzezga received funding by Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD, grant agreement number: 115952), DFG (Deutsche Forschungsgemeinschaft), BMBF (Bundesministerium für Bildung und Forschung), EFRE/Leitmarkt (Europäischen Fonds für regionale Entwicklung), University of Cologne, Forschungszentrum Jülich. Novartis clinical trial. Claus Escher received funding from the EU-EFPIA Innovative Medicines Initiatives 2 Joint Undertaking (IMI 2 JU) European Prevention of Alzheimer's Dementia consortium (EPAD, grant agreement number: 115736) and Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD, grant agreement number: 115952). Frank Jessen received funding from BMBF, DFG, H2020, and IMI. Agneta Nordberg received funding from Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD, grant agreement number: 115952), Swedish Foundation for Strategic Research (RB12-01929), Swedish Research Council (2017-06086, 2017-02965, 2020-019909, CIMED, Swedish Brain Foundation, Swedish Alzheimer foundation, Recherche Sur Alzheimer Fondation, France, and Michael J Fox Foundation (MJFF-019728). Zuzana Walker received funding from HTA-NIHR, Lewy body Society, and ARUK. Jean-François Demonet received funding from Biogen “EMBARK” study, Empiris foundation, Solis foundation, OM Pharma, and Leenaards foundation. Frederik Barkhof is supported by the NIHR Biomedical Research Centre at University College London Hospitals. Giovanni B. Frisoni received funding from the EU-EFPIA Innovative Medicines Initiatives 2 Joint Undertaking (IMI 2 JU) European Prevention of Alzheimer's Dementia consortium (EPAD, grant agreement number: 115736) and Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD, grant agreement number: 115952); the Swiss National Science Foundation (COSCODE, grant number: 320030_182772); A.P.R.A. - Association Suisse pour la Recherche sur la Maladie d'Alzheimer, Genève; Fondation Segré, Genève; Ivan Pictet, Genève; Fondazione Agusta, Lugano; Fondation Chmielewski, Genève; and VELUX Foundation. Open access funding provided by Universite de Geneve.

Cross-sectional studies have indicated potential for positron emission tomography (PET) in imaging tau pathology in Alzheimer's disease (AD); however, its prognostic utility remains unproven. In a longitudinal, multi-modal, prognostic study of cognitive decline, 20 patients with a clinical biomarker-based diagnosis in the AD spectrum (mild cognitive impairment or dementia and a positive amyloid-beta PET scan) were recruited from the Cognitive Clinic at Karolinska University Hospital. The participants underwent baseline neuropsychological assessment, PET imaging with [F-18]THK5317, [C-11]PIB and [F-18]FDG, magnetic resonance imaging, and in a subgroup cerebrospinal fluid (CSF) sampling, with clinical follow-up after a median 48 months (interquartile range = 32:56). In total, 11 patients declined cognitively over time, while 9 remained cognitively stable. The accuracy of baseline [F-18]THK5317 binding in temporal areas was excellent at predicting future cognitive decline (area under the receiver operating curve 0.84-1.00) and the biomarker levels were strongly associated with the rate of cognitive decline (beta estimate -33.67 to -31.02,p < 0.05). The predictive accuracy of the other baseline biomarkers was poor (area under the receiver operating curve 0.58-0.77) and their levels were not associated with the rate of cognitive decline (beta estimate -4.64 to 15.78,p > 0.05). Baseline [F-18]THK5317 binding and CSF tau levels were more strongly associated with the MMSE score at follow-up than at baseline (p < 0.05). These findings support a temporal dissociation between tau deposition and cognitive impairment, and suggest that [F-18]THK5317 predicts future cognitive decline better than other biomarkers. The use of imaging markers for tau pathology could prove useful for clinical prognostic assessment and screening before inclusion in relevant clinical trials.

Introduction: The disconnection hypothesis of Alzheimer's disease (AD) is supported by growing neuroimaging and neurophysiological evidence of altered brain functional connectivity in cognitively impaired individuals. Brain functional modalities such as [18F]fluorodeoxyglucose positron-emission tomography ([18F]FDG-PET) and electroencephalography (EEG) measure different aspects of synaptic functioning, and can contribute to understanding brain connectivity disruptions in AD. Aim: This study investigated the relationship between cortical glucose metabolism and topographical EEG measures of brain functional connectivity in subjects along AD continuum. Methods: Patients diagnosed with mild cognitive impairment (MCI) and AD (n = 67), and stratified into amyloid-positive (n = 32) and negative (n = 10) groups according to cerebrospinal fluid Aβ42/40 ratio, were assessed with [18F]FDG-PET and resting-state EEG recordings. EEG-based neuroimaging analysis involved standardized low-resolution electromagnetic tomography (sLORETA), which estimates functional connectivity from cortical sources of electrical activity in a 3D head model. Results: Glucose hypometabolism in temporoparietal lobes was significantly associated with altered EEG functional connectivity of the same regions of interest in clinically diagnosed MCI and AD patients and in patients with biomarker-verified AD pathology. The correlative pattern of disrupted connectivity in temporoparietal lobes, as detected by EEG sLORETA analysis, included decreased instantaneous linear connectivity in fast frequencies and increased lagged linear connectivity in slow frequencies in relation to the activity of remaining cortex. Conclusions: Topographical EEG measures of functional connectivity detect regional dysfunction of AD-vulnerable brain areas as evidenced by association and spatial overlap with the cortical glucose hypometabolism in MCI and AD patients. Impact statement The association between glucose hypometabolism, as evidenced by [18F]FDG-PET ([18F]fluorodeoxyglucose positron-emission tomography), and altered electroencephalography (EEG) functional connectivity metrics within temporoparietal lobes provides link between synaptic, neurophysiological, and metabolic impairment in mild cognitive impairment and Alzheimer's disease patients. This study reported alterations in EEG measures of both instantaneous and lagged linear connectivity across distinct frequency bands, both of which were shown to be important for inter- and intrahemispheric communication and function of memory systems in general. EEG-based imaging of brain functional connectivity has a potential to serve as a noninvasive, low-cost, and widely available alternative in assessing synaptic and network dysfunction in cognitively impaired patients.

Objective To perform a comprehensive characterization of a cohort of patients with chorea-acanthocytosis (ChAc) in Sweden. Methods Clinical assessments, targeted genetic studies, neuroimaging with MRI, [18F]-fluorodeoxyglucose (FDG) PET, and dopamine transporter with 123I FP-CIT (DaTscan) SPECT. One patient underwent magnetic resonance spectroscopy (MRS). Results Four patients living in Sweden but with different ethnical backgrounds were included. Their clinical features were variable. Biallelic VPS13A mutations were confirmed in all patients, including 3 novel mutations. All tested patients had either low or absent chorein levels. One patient had progressive caudate atrophy. Investigation using FDG-PET revealed severe bilateral striatal hypometabolism, and DaTscan SPECT displayed presynaptic dopaminergic deficiency in 3 patients. MRS demonstrated reduced N-acetylaspartate/creatine (Cr) ratio and mild elevation of both choline/Cr and combined glutamate and glutamine/Cr in the striatum in 1 case. One patient died during sleep, and another was treated with deep brain stimulation, which transiently attenuated feeding dystonia but not his gait disorder or chorea. Conclusions Larger longitudinal neuroimaging studies with different modalities, particularly MRS, are needed to determine their potential role as biomarkers for ChAc.

OBJECTIVE: To identify brain regions whose metabolic impairment contributes to DLB clinical core features expression and to assess the influence of severity of global cognitive impairment on the DLB-hypometabolic-pattern. METHODS: Brain FDG-PET and information on core features were available in 171 patients belonging to the imaging repository of the European DLB-consortium. Principal component analysis was applied to identify brain regions relevant to the local data variance. A linear regression model was applied to generate core feature-specific patterns controlling for the main confounding variables (MMSE, Age, Education, Gender, and Center). Regression analysis to the locally-normalized intensities was performed to generate a MMSE score-sensitive map. RESULTS: Parkinsonism negatively covaried with bilateral parietal, precuneus and anterior cingulate metabolism, visual-hallucinations with bilateral dorsolateral-frontal cortex, posterior cingulate and parietal metabolism and RBD with bilateral parieto-occipital cortex, precuneus and ventrolateral-frontal metabolism. VH and RBD shared a positive covariance with metabolism in medial temporal lobe, cerebellum, brainstem, basal ganglia, thalami, orbitofrontal and sensorimotor cortex. Cognitive fluctuations negatively covaried with occipital metabolism and positively with parietal lobes metabolism. MMSE positively covaried with metabolism in left superior frontal gyrus, bilateral-parietal cortex, and left precuneus, and negatively with metabolism in insula, medial frontal gyrus, hippocampus in the left hemisphere and in right cerebellum. INTERPRETATION: Regions of more preserved metabolism are relatively consistent across the variegate DLB spectrum. By contrast, core features were associated to more prominent hypometabolism in specific regions thus suggesting a close clinical-imaging correlation, reflecting the interplay between topography of neurodegeneration and clinical presentation in DLB patients. This article is protected by copyright. All rights reserved.

OBJECTIVE: LMNB1-related autosomal dominant leukodystrophy is caused by an overexpression of the protein lamin B1, usually due to a duplication of the LMNB1 gene. Symptoms start in 5th to 6th decade. This slowly progressive disease terminates with death. We studied brain glucose metabolism in this disease using 18 F-fluorodeoxyglucose positron emission tomography (PET). METHODS: We examined 8 patients, aged 48-64 years, in varying stages of clinical symptomatology. Two patients were investigated with quantitative PET on clinical indications after which six more patients were recruited. Absolute glucose metabolism was analyzed with the PVElab software in 6 patients and 18 healthy controls. A semiquantitative analysis using the CortexID software was performed in seven investigations, relating local metabolism levels to global glucose metabolism. RESULTS: The clinical quantitative PET revealed low global glucose metabolism, with the most marked reduction in the cerebellum. In the PVElab analysis, patients presented low mean glucose metabolism in the cerebellum, brainstem and global grey matter. In the semiquantitative analysis, 2 patients showed a decreased metabolism in the cerebellum and 4 patients a relatively higher metabolism in parts of the temporal lobes. Since none of the patients showed an increased metabolism in the quantitative analysis, we interpret these increases as "pseudo-increases" related to a globally reduced metabolism. CONCLUSIONS: Global reduction of grey matter glucose metabolism in this white matter disease most likely depends on a combination of cortical afferent dysfunction and, in later stages, neuronal loss. The lowest metabolism in the cerebellum is consistent with histopathological findings and prominent cerebellar symptoms.