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Background and Objectives: Preclinical Alzheimer disease (AD) trials simultaneously test candidate treatments and the implications of disclosing biomarker information to cognitively unimpaired individuals. Methods: The EARLY trial was a randomized, double-blind, placebo-controlled, phase 2b/3 study conducted in 143 centers across 14 countries from November 2015 to December 2018 after being stopped prematurely because of treatment-related hepatotoxicity. Participants age 60-85 years deemed cognitively unimpaired were disclosed an elevated or not elevated brain amyloid result by a certified clinician. Among 3,686 participants, 2,066 underwent amyloid imaging, 1,394 underwent CSF biomarker assessment, and 226 underwent both. Among biomarker-tested participants with at least one change score on an outcome of interest, 680 with elevated and 2,698 with not elevated amyloid were included in this analysis. We compared the Geriatric Depression Scale (GDS), the State-Trait Anxiety Scale (STAI), and the Columbia Suicide Severity Rating Scale (CSSRS) before disclosure between amyloid groups. After disclosure, we assessed for differences in the Impact of Events Scale (IES, collected 24-72 hours after disclosure), a measure of intrusive thoughts. Additional scales included the Concerns for AD scale. Results: Among 3378 included participants, the mean (SD) age was 69.0 (5.3); most were female (60%) and White race (84%). No differences were observed before disclosure between participants with elevated and not elevated amyloid for the GDS, STAI, or CSSRS. Participants with elevated amyloid demonstrated higher Concerns for AD scores compared with participants with not elevated amyloid before disclosure. Participants with elevated amyloid demonstrated higher IES scores (9.6 [10.8] vs 5.1 [8.0]) after disclosure and increased Concerns about AD. Patterns of reactions (elevated vs not elevated) were similar for biomarker modalities, although scores were lower among those undergoing CSF compared with PET testing. Although score differences were apparent comparing geographical regions, patterns of group differences were similar. Discussion: Although sample bias must be considered, these results suggest that amyloid disclosure resulted in increased perceived risk and mild distress in those learning an elevated result. Although this study did not assess psychological safety, observed associations intrusive thoughts and distress could be important considerations in the future clinical practice.
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The Alzheimer's Disease Neuroimaging Initiative (ADNI) Private Partners Scientific Board (PPSB) encompasses members from industry, biotechnology, diagnostic, and non-profit organizations that have until recently been managed by the Foundation for the National Institutes of Health (FNIH) and provided financial and scientific support to ADNI programs. In this article, we review some of the major activities undertaken by the PPSB, focusing on those supporting the most recently completed National Institute on Aging grant, ADNI3, and the impact it has had on streamlining biomarker discovery and validation in Alzheimer's disease. We also provide a perspective on the gaps that may be filled with future PPSB activities as part of ADNI4 and beyond. HIGHLIGHTS: The Private Partners Scientific board (PPSB) continues to play a key role in enabling several Alzheimer's Disease Neuroimaging Initiative (ADNI) activities. PPSB working groups have led landscape assessments to provide valuable feedback on new technologies, platforms, and methods that may be taken up by ADNI in current or future iterations.
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Enfermedad de Alzheimer , Investigación Biomédica , Factores de Coagulación Sanguínea , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Neuroimagen/métodos , BiomarcadoresRESUMEN
BACKGROUND: Atabecestat, a potent brain penetrable BACE1 inhibitor that reduces CSF amyloid beta (Aß), was developed as an oral treatment for Alzheimer's disease (AD). Elevated liver enzyme adverse events were reported in three studies although only one case met Hy's law criteria to predict serious hepatotoxicity. METHOD: We performed a case-control genome-wide association study (GWAS) to identify genetic risk variants associated with liver enzyme elevation using 42 cases with alanine transaminase (ALT) above three times the upper limit of normal (ULN) and 141 controls below ULN. Additionally, we performed a GWAS using continuous maximal ALT/ULN (expressed as times the ULN) upon exposure to atabecestat as the outcome measure (n = 285). RESULTS: No variant passed the genome-wide significance threshold (p = 5 × 10- 8) in the case-control GWAS. We identified suggestive association signals in genes (NLRP1, SCIMP, and C1QBP) implicated in the inflammatory processes. Among the genes implicated by position mapping using variants suggestively associated (p < 1 × 10- 5) with ALT elevation case-control status, gene sets involved in innate immune response (adjusted p-value = 0.05) and regulation of cytokine production (adjusted p-value = 0.04) were enriched. One genomic region in the intronic region of GABRG3 passed the genome-wide significance threshold in the continuous max(ALT/ULN) GWAS, and this variant was nominally associated with ALT elevation case status (p = 0.009). CONCLUSION: The suggestive GWAS signals in the case-control GWAS analysis suggest the potential role of inflammation in atabecestat-induced liver enzyme elevation.
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Secretasas de la Proteína Precursora del Amiloide , Estudio de Asociación del Genoma Completo , Humanos , Alanina Transaminasa , Secretasas de la Proteína Precursora del Amiloide/genética , Péptidos beta-Amiloides , Ácido Aspártico Endopeptidasas , Proteínas Portadoras , Proteínas MitocondrialesRESUMEN
Well-designed placebo-controlled clinical trials are critical to the development of novel treatments for epilepsy, but their design has not changed for decades. Patients, clinicians, regulators, and innovators all have concerns that recruiting for trials is challenging, in part, due to the static design of maintaining participants for long periods on add-on placebo when there are an increasing number of options for therapy. A traditional trial maintains participants on blinded treatment for a static period (e.g., 12 weeks of maintenance), during which participants on placebo have an elevated risk of sudden unexpected death in epilepsy compared to patients on an active treatment. Time-to-event trials observe participants on blinded treatment until a key event occurs (e.g., post-randomization seizure count matches pre-randomization monthly seizure count). In this article, we review the evidence for these designs based on re-analysis of prior trials, one published trial that used a time-to-second seizure design, and experience from an ongoing blinded trial. We also discuss remaining concerns regarding time-to-event trials. We conclude that, despite potential limitations, time-to-event trials are a potential promising mechanism to make trials more patient friendly and reduce placebo exposure, which are urgent needs to improve safety and increase recruitment to trials.
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Anticonvulsivantes , Epilepsia , Humanos , Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Epilepsia/inducido químicamente , Proyectos de Investigación , Convulsiones/tratamiento farmacológico , Convulsiones/inducido químicamente , Ensayos Clínicos como AsuntoRESUMEN
OBJECTIVE: The prevalence of epilepsy is slightly higher in women than in men and sensitivity to seizure stimuli differs between sexes. Some evidence suggests sex differences in response to antiseizure medications exist mainly due to inconsistent pharmacokinetic differences; however, there is a lack of real-world evidence examining differences in response to antiseizure medications between men and women. METHODS: This was a retrospective population-based cohort study in five large US healthcare databases. The population included adult patients with epilepsy, newly exposed to levetiracetam, and naive to antiseizure medication. The first exposure to levetiracetam was the index date. The requirement that all patients received the same medication was done to avoid potential confounding due to differences in index treatment. The outcome was the development of treatment resistant epilepsy (TRE), defined as having at least three distinct antiseizure medications in 1 year. The proportion of patients who developed TRE within 1 year following the index date was calculated. To compare the risk of developing TRE between sexes, relative risks (RR) and 95% confidence intervals (CI) were calculated, and estimates were pooled using meta-analytic techniques stratified by gender and age. RESULTS: A total of 147 334 subjects were included in the databases, 50.8% were women, and 4.27% developed TRE. The comorbid profile differed greatly between men and women; however, the types of epilepsy syndromes observed during baseline were similar between the two groups. Across all databases, women were more likely to develop TRE than men (pooled RR 1.27, 95% CI 1.17-1.38). Results remained similar when stratified by age. SIGNIFICANCE: This study assessed sex differences in response to antiseizure medications using the development of TRE as a proxy for effectiveness. Women newly exposed to levetiracetam were 27% more likely to develop TRE than men, independent of age.
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Anticonvulsivantes , Epilepsia , Adulto , Femenino , Humanos , Masculino , Levetiracetam/uso terapéutico , Anticonvulsivantes/uso terapéutico , Estudios Retrospectivos , Estudios de Cohortes , Epilepsia/tratamiento farmacológicoRESUMEN
Background: Practice effects (PE), after repeated cognitive measurements, may mask cognitive decline and represent a challenge in clinical and research settings. However, an attenuated practice effect may indicate the presence of brain pathologies. This study aimed to evaluate practice effects on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) scale, and their associations with brain amyloid status and other factors in a cohort of cognitively unimpaired older adults enrolled in the CHARIOT-PRO SubStudy. Materials and Methods: 502 cognitively unimpaired participants aged 60-85 years were assessed with RBANS in both screening and baseline clinic visits using alternate versions (median time gap of 3.5 months). We tested PE based on differences between test and retest scores in total scale and domain-specific indices. Multiple linear regressions were used to examine factors influencing PE, after adjusting for age, sex, education level, APOE-ε4 carriage and initial RBANS score. The latter and PE were also evaluated as predictors for amyloid positivity status based on defined thresholds, using logistic regression. Results: Participants' total scale, immediate memory and delayed memory indices were significantly higher in the second test than in the initial test (Cohen's dz = 0.48, 0.70 and 0.35, P < 0.001). On the immediate memory index, the PE was significantly lower in the amyloid positive group than the amyloid negative group (P = 0.022). Older participants (≥70 years), women, non-APOE-ε4 carriers, and those with worse initial RBANS test performance had larger PE. No associations were found between brain MRI parameters and PE. In addition, attenuated practice effects in immediate or delayed memory index were independent predictors for amyloid positivity (P < 0.05). Conclusion: Significant practice effects on RBANS total scale and memory indices were identified in cognitively unimpaired older adults. The association with amyloid status suggests that practice effects are not simply a source of measurement error but may be informative with regard to underlying neuropathology.
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INTRODUCTION: Epilepsy is a neurological disease characterized by recurrent, unprovoked seizures and its impact on biological, cognitive, psychological, and social outcomes. An unmet need for finding effective treatment options exists. Identifying medical diagnoses present prior to a diagnosis of epilepsy is an important step in increasing our understanding of how people with epilepsy may respond to therapy, help guide clinicians in managing associated comorbid conditions, and inform future research. METHODS: A population-based retrospective comparative cohort study was conducted using administrative claims data to explore differences in medical diagnoses prior to an initial diagnosis of epilepsy between patients with and without drug-resistant epilepsy (DRE) identified within one-year post diagnosis by evaluating standardized mean differences between the groups. RESULTS: A total of 205,183 patients with newly diagnosed epilepsy were identified. Of those, 4.1% (nâ¯=â¯8340) were considered drug resistant one-year post diagnosis. Pain and mood disorders were the common physical and psychiatric diagnoses in both cohorts. Differences between the newly diagnosed epilepsy and DRE cohorts were observed. Patients in the DRE cohort were younger, had more encounters with the healthcare system, and higher burden of disease for both physical (e.g., headache, neuropathy, muscular-skeletal disorders, and traumatic brain injury) and psychiatric diagnoses (e.g., depression, anxiety, bipolar disorder, suicidal thoughts, drug dependency, and sleep disorders). CONCLUSION: Physical and psychiatric diagnoses are common one year prior to first diagnosis of epilepsy in administrative claims data. Compared to patients without DRE, those who develop DRE within one-year post initial diagnosis demonstrated a higher burden of disease.
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Epilepsia , Preparaciones Farmacéuticas , Estudios de Cohortes , Epilepsia/diagnóstico , Epilepsia/epidemiología , Humanos , Estudios Retrospectivos , Convulsiones/diagnóstico , Convulsiones/epidemiologíaRESUMEN
INTRODUCTION: The Cognitive Health in Ageing Register: Investigational, Observational and Trial Studies in Dementia Research (CHARIOT): Prospective Readiness cOhort (PRO) SubStudy (CPSS), sponsored by Janssen Pharmaceutical Research & Development LLC, is an Alzheimer's disease (AD) biomarker enriched observational study that began 3 July 2015 CPSS aims to identify and validate determinants of AD, alongside cognitive, functional and biological changes in older adults with or without detectable evidence of AD pathology at baseline. METHODS AND ANALYSIS: CPSS is a dual-site longitudinal cohort (3.5 years) assessed quarterly. Cognitively normal participants (60-85 years) were recruited across Greater London and Edinburgh. Participants are classified as high, medium (amnestic or non-amnestic) or low risk for developing mild cognitive impairment-Alzheimer's disease based on their Repeatable Battery for the Assessment of Neuropsychological Status performance at screening. Additional AD-related assessments include: a novel cognitive composite, the Global Preclinical Alzheimer's Cognitive Composite, brain MRI and positron emission tomography and cerebrospinal fluid analysis. Lifestyle, other cognitive and functional data, as well as biosamples (blood, urine, and saliva) are collected. Primarily, study analyses will evaluate longitudinal change in cognitive and functional outcomes. Annual interim analyses for descriptive data occur throughout the course of the study, although inferential statistics are conducted as required. ETHICS AND DISSEMINATION: CPSS received ethical approvals from the London-Central Research Ethics Committee (15/LO/0711) and the Administration of Radioactive Substances Advisory Committee (RPC 630/3764/33110) The study is at the forefront of global AD prevention efforts, with frequent and robust sampling of the well-characterised cohort, allowing for detection of incipient pathophysiological, cognitive and functional changes that could inform therapeutic strategies to prevent and/or delay cognitive impairment and dementia. Dissemination of results will target the scientific community, research participants, volunteer community, public, industry, regulatory authorities and policymakers. On study completion, and following a predetermined embargo period, CPSS data are planned to be made accessible for analysis to facilitate further research into the determinants of AD pathology, onset of symptomatology and progression. TRIAL REGISTRATION NUMBER: The CHARIOT:PRO SubStudy is registered with clinicaltrials.gov (NCT02114372). Notices of protocol modifications will be made available through this trial registry.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Envejecimiento , Enfermedad de Alzheimer/diagnóstico , Cognición , Disfunción Cognitiva/diagnóstico , Progresión de la Enfermedad , Humanos , Londres , Pruebas Neuropsicológicas , Estudios Observacionales como Asunto , Estudios ProspectivosRESUMEN
Importance: Atabecestat, a nonselective oral ß-secretase inhibitor, was evaluated in the EARLY trial for slowing cognitive decline in participants with preclinical Alzheimer disease. Preliminary analyses suggested dose-related cognitive worsening and neuropsychiatric adverse events (AEs). Objective: To report efficacy, safety, and biomarker findings in the EARLY trial, both on and off atabecestat treatment, with focus on potential recovery of effects on cognition and behavior. Design, Setting, and Participants: Randomized, double-blind, placebo-controlled, phase 2b/3 study conducted from November 2015 to December 2018 after being stopped prematurely. The study was conducted at 143 centers across 14 countries. Participants were permitted to be followed off-treatment by the original protocol, collecting safety and efficacy data. From 4464 screened participants, 557 amyloid-positive, cognitively normal (Clinical Dementia Rating of 0; aged 60-85 years) participants (approximately 34% of originally planned 1650) were randomized before the trial sponsor stopped enrollment. Interventions: Participants were randomized (1:1:1) to atabecestat, 5 mg (n = 189), 25 mg (n = 183), or placebo (n = 185). Main Outcomes and Measures: Primary outcome: change from baseline in Preclinical Alzheimer Cognitive Composite score. Secondary outcomes: change from baseline in the Cognitive Function Index and the Repeatable Battery for the Assessment of Neuropsychological Status total scale score. Safety was monitored throughout the study. Results: Of 557 participants, 341 were women (61.2%); mean (SD) age was 70.4 (5.56) years. In May 2018, study medication was stopped early owing to hepatic-related AEs; participants were followed up off-treatment for 6 months. Atabecestat, 25 mg, showed significant cognitive worsening vs placebo for Preclinical Alzheimer Cognitive Composite at month 6 (least-square mean difference, -1.09; 95% CI, -1.66 to -0.53; P < .001) and month 12 (least-square mean, -1.62; 95% CI, -2.49 to -0.76; P < .001), and at month 3 for Repeatable Battery for the Assessment of Neuropsychological Status (least-square mean, -3.70; 95% CI, -5.76 to -1.63; P < .001). Cognitive Function Index participant report showed nonsignificant worsening at month 12. Systemic and neuropsychiatric-related treatment-emergent AEs were greater in atabecestat groups vs placebo. After stopping treatment, follow-up cognitive testing and AE assessment provided evidence of reversibility of drug-induced cognitive worsening and AEs in atabecestat groups. Conclusions and Relevance: Atabecestat treatment was associated with dose-related cognitive worsening as early as 3 months and presence of neuropsychiatric treatment-emergent AEs, with evidence of reversibility after 6 months off treatment. Trial Registration: ClinicalTrials.gov Identifier: NCT02569398.
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Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Piridinas/administración & dosificación , Piridinas/efectos adversos , Tiazinas/administración & dosificación , Tiazinas/efectos adversos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/enzimología , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Biomarcadores/metabolismo , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Trastornos Mentales/inducido químicamente , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
PURPOSE: Real-world studies to describe the use of first, second and third line therapies for the management and symptomatic treatment of dementia are lacking. This retrospective cohort study describes the first-, second- and third-line therapies used for the management and symptomatic treatment of dementia, and in particular Alzheimer's Disease. METHODS: Medical records of patients with newly diagnosed dementia between 1997 and 2017 were collected using four databases from the UK, Denmark, Italy and the Netherlands. RESULTS: We identified 191,933 newly diagnosed dementia patients in the four databases between 1997 and 2017 with 39,836 (IPCI (NL): 3281, HSD (IT): 1601, AUH (DK): 4474, THIN (UK): 30,480) fulfilling the inclusion criteria, and of these, 21,131 had received a specific diagnosis of Alzheimer's disease. The most common first line therapy initiated within a year (± 365 days) of diagnosis were Acetylcholinesterase inhibitors, namely rivastigmine in IPCI, donepezil in HSD and the THIN and the N-methyl-D-aspartate blocker memantine in AUH. CONCLUSION: We provide a real-world insight into the heterogeneous management and treatment pathways of newly diagnosed dementia patients and a subset of Alzheimer's Disease patients from across Europe.
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Enfermedad de Alzheimer , Registros Electrónicos de Salud , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Europa (Continente) , Galantamina , Humanos , Indanos , Italia , Países Bajos , Fenilcarbamatos , Piperidinas , Estudios RetrospectivosRESUMEN
OBJECTIVES: Determinants of cognitive functioning in individuals aged 90 years and older, the oldest-old, remain poorly understood. We aimed to establish the association of risk factors, white matter hyperintensities (WMHs), hippocampal atrophy, and amyloid aggregation with cognition in the oldest-old. METHOD: We included 84 individuals without cognitive impairment and 38 individuals with cognitive impairment from the EMIF-AD 90+ Study (mean age 92.4 years) and tested cross-sectional associations between risk factors (cognitive activity, physical parameters, nutritional status, inflammatory markers, and cardiovascular risk factors), brain pathology biomarkers (WMH and hippocampal volume on magnetic resonance imaging, and amyloid binding measured with positron emission tomography), and cognition. Additionally, we tested whether the brain pathology biomarkers were independently associated with cognition. When applicable, we tested whether the effect of risk factors on cognition was mediated by brain pathology. RESULTS: Lower values for handgrip strength, Short Physical Performance Battery (SPPB), nutritional status, HbA1c, and hippocampal volume, and higher values for WMH volume and amyloid binding were associated with worse cognition. Higher past cognitive activity and lower body mass index were associated with increased amyloid binding, lower muscle mass with more WMH, and lower SPPB scores with more WMH and hippocampal atrophy. The brain pathology markers were independently associated with cognition. The association of SPPB with cognition was partially mediated by hippocampal volume. DISCUSSION: In the oldest-old, physical parameters, nutritional status, HbA1c, WMH, hippocampal atrophy, and amyloid binding are associated with cognitive impairment. Physical performance may affect cognition through hippocampal atrophy. This study highlights the importance to consider multiple factors when assessing cognition in the oldest-old.
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Enfermedad de Alzheimer , Péptidos beta-Amiloides/metabolismo , Envejecimiento Cognitivo/fisiología , Disfunción Cognitiva , Estado de Salud , Hipocampo/patología , Sustancia Blanca/patología , Anciano de 80 o más Años , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Atrofia/patología , Estudios de Casos y Controles , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/patología , Disfunción Cognitiva/fisiopatología , Europa (Continente) , Femenino , Hemoglobina Glucada , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía de Emisión de Positrones , Sustancia Blanca/diagnóstico por imagenRESUMEN
BACKGROUND: Atabecestat, a potent brain-penetrable inhibitor of BACE1 activity that reduces CSF amyloid beta (Aß), was developed for oral treatment for Alzheimer's disease (AD). The long-term safety and effect of atabecestat on cognitive performance in participants with predementia AD in two phase 2 studies were assessed. METHODS: In the placebo-controlled double-blind parent ALZ2002 study, participants aged 50 to 85 years were randomized (1:1:1) to placebo or atabecestat 10 or 50 mg once daily (later reduced to 5 and 25 mg) for 6 months. Participants entered ALZ2004, a 12-month treatment extension with placebo or atabecestat 10 or 25 mg, followed by an open-label phase. Safety, changes in CSF biomarker levels, brain volume, and effects on cognitive performance were assessed. RESULTS: Of 114 participants randomized in ALZ2002, 99 (87%) completed, 90 entered the ALZ2004 double-blind phase, and 77 progressed to the open-label phase. CSF Aß fragments and sAPPß were reduced dose-proportionately. Decreases in whole brain and hippocampal volumes were greater in participants with mild cognitive impairment (MCI) due to AD than in preclinical AD, but were not affected by treatment. In ALZ2004, change from baseline in RBANS trended toward worse scores for atabecestat versus placebo. Elevated liver enzyme adverse events reported in 12 participants on atabecestat resulted in dosage modification and increased frequency of safety monitoring. Treatment discontinuation normalized ALT or AST in all except one with pretreatment elevation, which remained mildly elevated. No case met ALT/AST > 3× ULN and total bilirubin > 2× ULN (Hy's law). CONCLUSION: Atabecestat was associated with trend toward declines in cognition, and elevation of liver enzymes. TRIAL REGISTRATION: ALZ2002: ClinicalTrials.gov, NCT02260674, registered October 9, 2014; ALZ2004: ClinicalTrials.gov, NCT02406027, registered April 1, 2015.
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Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides , Ácido Aspártico Endopeptidasas , Método Doble Ciego , Humanos , Piridinas , Tiazinas , Resultado del TratamientoRESUMEN
BACKGROUND: Hippocampal atrophy (HA) is one of the biomarkers for Alzheimer's disease (AD). OBJECTIVE: To identify the best biomarkers and develop models for prediction of HA over 24 months using baseline data. METHODS: The study included healthy elderly controls, subjects with mild cognitive impairment, and subjects with AD, obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI 1) and the Australian Imaging Biomarkers and Lifestyle Flagship Study of Ageing (AIBL) databases. Predictor variables included cognitive and neuropsychological tests, amyloid-ß, tau, and p-tau from cerebrospinal fluid samples, apolipoprotein E, and features extracted from magnetic resonance images (MRI). Least-mean-squares regression with elastic net regularization and least absolute deviation regression models were tested using cross-validation in ADNI 1. The generalizability of the models including only MRI features was evaluated by training the models with ADNI 1 and testing them with AIBL. The models including the full set of variables were not evaluated with AIBL because not all needed variables were available in it. RESULTS: The models including the full set of variables performed better than the models including only MRI features (root-mean-square error (RMSE) 1.76-1.82 versus 1.93-2.08). The MRI-only models performed well when applied to the independent validation cohort (RMSE 1.66-1.71). In the prediction of dichotomized HA (fast versus slow), the models achieved a reasonable prediction accuracy (0.79-0.87). CONCLUSIONS: These models can potentially help identifying subjects predicted to have a faster HA rate. This can help in selection of suitable patients into clinical trials testing disease-modifying drugs for AD.
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Enfermedad de Alzheimer/patología , Hipocampo/patología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides/líquido cefalorraquídeo , Atrofia/líquido cefalorraquídeo , Atrofia/diagnóstico por imagen , Atrofia/patología , Biomarcadores , Progresión de la Enfermedad , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Análisis Multivariante , Proteínas tau/líquido cefalorraquídeoRESUMEN
INTRODUCTION: Performance of "Revere", a novel iPad-administered word-list recall (WLR) test, in quantifying deficits in verbal episodic memory, was evaluated versus examiner-administered Rey Auditory Verbal Learning Test (RAVLT) in patients with mild cognitive impairment and cognitively normal participants. METHODS: Elderly patients with clinically diagnosed mild cognitive impairment (Montreal Cognitive Assessment score 24-27) and cognitively normal (Montreal Cognitive Assessment score ≥28) were administered RAVLT or Revere in a randomized crossover design. RESULTS: A total of 153/161 participants (Revere/RAVLT n = 75; RAVLT/Revere n = 78) were randomized; 148 (97%) completed study; 121 patients (mean [standard deviation] age: 70.4 [7.84] years) were included for analysis. Word-list recall scores (8 trials) were comparable between Revere and RAVLT (Pearson's correlation coefficients: 0.12-0.70; least square mean difference [Revere-RAVLT]: -0.84 [90% CI, -1.15; -0.54]). Model factor estimates indicated trial (P < .001), period (P < .001) and evaluation sequence (P = .038) as significant factors. Learning over trials index and serial position effects were comparable. DISCUSSION: Participants' verbal recall performance on Revere and RAVLT were equivalent.
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BACKGROUND: The oldest-old (subjects aged 90 years and older) population represents the fastest growing segment of society and shows a high dementia prevalence rate of up to 40%. Only a few studies have investigated protective factors for cognitive impairment in the oldest-old. The EMIF-AD 90+ Study aims to identify factors associated with resilience to cognitive impairment in the oldest-old. In this paper we reviewed previous studies on cognitive resilience in the oldest-old and described the design of the EMIF-AD 90+ Study. METHODS: The EMIF-AD 90+ Study aimed to enroll 80 cognitively normal subjects and 40 subjects with cognitive impairment aged 90 years or older. Cognitive impairment was operationalized as amnestic mild cognitive impairment (aMCI), or possible or probable Alzheimer's Disease (AD). The study was part of the European Medical Information Framework for AD (EMIF-AD) and was conducted at the Amsterdam University Medical Centers (UMC) and at the University of Manchester. We will test whether cognitive resilience is associated with cognitive reserve, vascular comorbidities, mood, sleep, sensory system capacity, physical performance and capacity, genetic risk factors, hallmarks of ageing, and markers of neurodegeneration. Markers of neurodegeneration included an amyloid positron emission tomography, amyloid ß and tau in cerebrospinal fluid/blood and neurophysiological measures. DISCUSSION: The EMIF-AD 90+ Study will extend our knowledge on resilience to cognitive impairment in the oldest-old by extensive phenotyping of the subjects and the measurement of a wide range of potential protective factors, hallmarks of aging and markers of neurodegeneration. TRIAL REGISTRATION: Nederlands Trial Register NTR5867 . Registered 20 May 2016.
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Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/psicología , Envejecimiento Saludable/psicología , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides/metabolismo , Biomarcadores/metabolismo , Estudios de Casos y Controles , Cognición/fisiología , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/metabolismo , Femenino , Envejecimiento Saludable/metabolismo , Humanos , Masculino , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: With the shift of research focus towards the pre-dementia stage of Alzheimer's disease (AD), there is an urgent need for reliable, non-invasive biomarkers to predict amyloid pathology. The aim of this study was to assess whether easily obtainable measures from structural MRI, combined with demographic data, cognitive data and apolipoprotein E (APOE) ε4 genotype, can be used to predict amyloid pathology using machine-learning classification. METHODS: We examined 810 subjects with structural MRI data and amyloid markers from the European Medical Information Framework for Alzheimer's Disease Multimodal Biomarker Discovery study, including subjects with normal cognition (CN, n = 337, age 66.5 ± 7.2, 50% female, 27% amyloid positive), mild cognitive impairment (MCI, n = 375, age 69.1 ± 7.5, 53% female, 63% amyloid positive) and AD dementia (n = 98, age 67.0 ± 7.7, 48% female, 97% amyloid positive). Structural MRI scans were visually assessed and Freesurfer was used to obtain subcortical volumes, cortical thickness and surface area measures. We first assessed univariate associations between MRI measures and amyloid pathology using mixed models. Next, we developed and tested an automated classifier using demographic, cognitive, MRI and APOE ε4 information to predict amyloid pathology. A support vector machine (SVM) with nested 10-fold cross-validation was applied to identify a set of markers best discriminating between amyloid positive and amyloid negative subjects. RESULTS: In univariate associations, amyloid pathology was associated with lower subcortical volumes and thinner cortex in AD-signature regions in CN and MCI. The multi-variable SVM classifier provided an area under the curve (AUC) of 0.81 ± 0.07 in MCI and an AUC of 0.74 ± 0.08 in CN. In CN, selected features for the classifier included APOE ε4, age, memory scores and several MRI measures such as hippocampus, amygdala and accumbens volumes and cortical thickness in temporal and parahippocampal regions. In MCI, the classifier including demographic and APOE ε4 information did not improve after additionally adding imaging measures. CONCLUSIONS: Amyloid pathology is associated with changes in structural MRI measures in CN and MCI. An automated classifier based on clinical, imaging and APOE ε4 data can identify the presence of amyloid pathology with a moderate level of accuracy. These results could be used in clinical trials to pre-screen subjects for anti-amyloid therapies.
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Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Anciano , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/líquido cefalorraquídeo , Apolipoproteína E4/genética , Biomarcadores , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Curva ROC , Máquina de Vectores de SoporteRESUMEN
We investigated whether amyloid-ß (Aß) and tau affected cognition in cognitively normal (CN) individuals, and whether norms for neuropsychological tests based on biomarker-negative individuals would improve early detection of dementia. We included 907 CN individuals from 8 European cohorts and from the Alzheimer's disease Neuroimaging Initiative. All individuals were aged above 40, had Aß status and neuropsychological data available. Linear mixed models were used to assess the associations of Aß and tau with five neuropsychological tests assessing memory (immediate and delayed recall of Auditory Verbal Learning Test, AVLT), verbal fluency (Verbal Fluency Test, VFT), attention and executive functioning (Trail Making Test, TMT, part A and B). All test except the VFT were associated with Aß status and this influence was augmented by age. We found no influence of tau on any of the cognitive tests. For the AVLT Immediate and Delayed recall and the TMT part A and B, we calculated norms in individuals without Aß pathology (Aß- norms), which we validated in an independent memory-clinic cohort by comparing their predictive accuracy to published norms. For memory tests, the Aß- norms rightfully identified an additional group of individuals at risk of dementia. For non-memory test we found no difference. We confirmed the relationship between Aß and cognition in cognitively normal individuals. The Aß- norms for memory tests in combination with published norms improve prognostic accuracy of dementia.
RESUMEN
BACKGROUND: Therapeutic research on Alzheimer's disease (AD) has moved to intercepting the disease at the preclinical phase. Most drugs in late development have focused on the amyloid hypothesis. OBJECTIVE: To understand the magnitude of amyloid-related functional decline and to identify the functional domains sensitive to decline in a preclinical AD population. METHODS: Data were from the Religious Orders Study and the Rush Memory and Aging Project. Cognitive decline was measured by a modified version of the Alzheimer's Disease Cooperative Study Preclinical Alzheimer Cognitive Composite. The trajectories of functional decline, as measured by the instrumental and basic activities of daily living, were longitudinally modeled in 484 participants without cognitive impairment at baseline and having both a final clinical and a postmortem neuropathology assessment of AD. RESULTS: Individuals with different final clinical diagnoses had different trajectories of cognitive and functional decline. Individuals with AD dementia, minor cognitive impairment, and no cognitive impairment had the most, intermediate, and least declines. While individuals with pathologic AD had significantly more cognitive decline over time than those without, the magnitude of difference in functional decline between these two groups was small. Functional domains such as handling finance and handling medications were more sensitive to decline. CONCLUSION: Demonstrating the functional benefit of an amyloid-targeting drug represents a significant challenge as elderly people experience functional decline due to a wide range of reasons with limited manifestation attributable to AD neuropathology. More sensitive functional scales focusing on the functional domains sensitive to decline in preclinical AD are needed.
Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Amiloidosis/patología , Disfunción Cognitiva/diagnóstico , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , Amiloidosis/complicaciones , Disfunción Cognitiva/epidemiología , Progresión de la Enfermedad , Femenino , Humanos , Modelos Lineales , Estudios Longitudinales , Masculino , Pruebas NeuropsicológicasRESUMEN
OBJECTIVE: To evaluate whether amyloid-related imaging abnormalities with edema/effusion (ARIA-E) observed in bapineuzumab clinical trials was associated with specific biomarker patterns. METHODS: Bapineuzumab, an anti-ß-amyloid monoclonal antibody, was evaluated in patients with mild to moderate Alzheimer disease. Amyloid PET imaging, CSF biomarkers, or volumetric MRI (vMRI) were assessed. RESULTS: A total of 1,512 participants underwent one or more biomarker assessments; 154 developed incident ARIA-E. No differences were observed at baseline between ARIA-E and non-ARIA-E participants in brain amyloid burden by PET, the majority of vMRI measures, or CSF biomarkers, with the exception of lower baseline CSF Aß42 in APOE ε4 noncarrier ARIA-E vs non-ARIA-E groups (bapineuzumab non-ARIA-E p = 0.027; placebo non-ARIA-E p = 0.012). At week 71, bapineuzumab-treated participants with ARIA-E vs non-ARIA-E showed greater reduction in brain amyloid PET, greater reductions in CSF phosphorylated tau (p-tau) (all comparisons p < 0.01), and total tau (t-tau) (all comparisons p < 0.025), and greater hippocampal volume reduction and ventricular enlargement (all p < 0.05). Greater reduction in CSF Aß40 concentrations was observed for ARIA-E versus both non-ARIA-E groups (bapineuzumab/placebo non-ARIA-E p = 0.015/0.049). No group differences were observed at week 71 for changes in whole brain volume or CSF Aß42. CONCLUSIONS: Baseline biomarkers largely do not predict risk for developing ARIA-E. ARIA-E was associated with significant longitudinal changes in several biomarkers, with larger reductions in amyloid PET and CSF p-tau and t-tau concentrations, and paradoxically greater hippocampal volume reduction and ventricular enlargement, suggesting that ARIA-E in bapineuzumab-treated cases may be related to increased Aß efflux from the brain and affecting downstream pathogenic processes.
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Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Biomarcadores/líquido cefalorraquídeo , Factores Inmunológicos/uso terapéutico , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/líquido cefalorraquídeo , Compuestos de Anilina/farmacocinética , Apolipoproteínas E/genética , Encéfalo/diagnóstico por imagen , Encéfalo/efectos de los fármacos , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Fragmentos de Péptidos/líquido cefalorraquídeo , Tomografía de Emisión de Positrones , Tiazoles/farmacocinética , Resultado del Tratamiento , Proteínas tau/líquido cefalorraquídeoRESUMEN
INTRODUCTION: The European Medical Information Framework consortium has assembled electronic health record (EHR) databases for dementia research. We calculated dementia prevalence and incidence in 25 million persons from 2004 to 2012. METHODS: Six EHR databases (three primary care and three secondary care) from five countries were interrogated. Dementia was ascertained by consensus harmonization of clinical/diagnostic codes. Annual period prevalences and incidences by age and gender were calculated and meta-analyzed. RESULTS: The six databases contained 138,625 dementia cases. Age-specific prevalences were around 30% of published estimates from community samples and incidences were around 50%. Pooled prevalences had increased from 2004 to 2012 in all age groups but pooled incidences only after age 75 years. Associations with age and gender were stable over time. DISCUSSION: The European Medical Information Framework initiative supports EHR data on unprecedented number of people with dementia. Age-specific prevalences and incidences mirror estimates from community samples in pattern at levels that are lower but increasing over time.