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INTRODUCTION/AIMS: Sporadic inclusion body myositis (IBM) is a degenerative and inflammatory acquired myopathy characterized by muscle deposition of various proteins typically associated with Alzheimer disease and other neurodegenerative diseases. Although cognitive impairment is not noted as a clinical feature of IBM, evidence is lacking. In this study we investigated whether cognitive performance of patients with IBM differs from population norms, focusing on cognitive domains affected in early Alzheimer disease (memory, executive function), and to test whether disease duration and the level of disability of IBM are associated with cognitive function. METHODS: Twenty-four patients with IBM (mean [standard deviation]: age, 62.0 [7.2] years; disease duration, 9.6 [4.8] years) were assessed cross-sectionally on neuropsychological tests covering multiple cognitive domains, including the Preclinical Alzheimer Cognitive Composite (PACC). Performance was compared with published normative data adjusted for age, sex, and education (National Alzheimer's Coordinating Center; N = 3268). Associations were examined between PACC score, disease duration, and level of disability (assessed using the IBM Functional Rating Scale [IBMFRS]). RESULTS: Across all cognitive tests, group performance was within ±1 standard deviation of the normative mean. There was no evidence of associations between PACC score and either disease duration (ρ = -0.04, P = .87) or IBMFRS total score (ρ = 0.14, P = .52). DISCUSSION: Memory and executive function in patients with IBM did not differ from normative data, and we observed no evidence of associations between the cognitive composite and disease duration or level of disability. This addresses a question frequently asked by patients and will be of value for clinicians and patients alike.
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Doença de Alzheimer , Miosite de Corpos de Inclusão , Estudos Transversais , Função Executiva/fisiologia , Humanos , Pessoa de Meia-Idade , Testes NeuropsicológicosRESUMO
Posterior cortical atrophy is a clinico-radiological syndrome characterized by progressive decline in visual processing and atrophy of posterior brain regions. With the majority of cases attributable to Alzheimer's disease and recent evidence for genetic risk factors specifically related to posterior cortical atrophy, the syndrome can provide important insights into selective vulnerability and phenotypic diversity. The present study describes the first major longitudinal investigation of posterior cortical atrophy disease progression. Three hundred and sixty-one individuals (117 posterior cortical atrophy, 106 typical Alzheimer's disease, 138 controls) fulfilling consensus criteria for posterior cortical atrophy-pure and typical Alzheimer's disease were recruited from three centres in the UK, Spain and USA. Participants underwent up to six annual assessments involving MRI scans and neuropsychological testing. We constructed longitudinal trajectories of regional brain volumes within posterior cortical atrophy and typical Alzheimer's disease using differential equation models. We compared and contrasted the order in which regional brain volumes become abnormal within posterior cortical atrophy and typical Alzheimer's disease using event-based models. We also examined trajectories of cognitive decline and the order in which different cognitive tests show abnormality using the same models. Temporally aligned trajectories for eight regions of interest revealed distinct (P < 0.002) patterns of progression in posterior cortical atrophy and typical Alzheimer's disease. Patients with posterior cortical atrophy showed early occipital and parietal atrophy, with subsequent higher rates of temporal atrophy and ventricular expansion leading to tissue loss of comparable extent later. Hippocampal, entorhinal and frontal regions underwent a lower rate of change and never approached the extent of posterior cortical involvement. Patients with typical Alzheimer's disease showed early hippocampal atrophy, with subsequent higher rates of temporal atrophy and ventricular expansion. Cognitive models showed tests sensitive to visuospatial dysfunction declined earlier in posterior cortical atrophy than typical Alzheimer's disease whilst tests sensitive to working memory impairment declined earlier in typical Alzheimer's disease than posterior cortical atrophy. These findings indicate that posterior cortical atrophy and typical Alzheimer's disease have distinct sites of onset and different profiles of spatial and temporal progression. The ordering of disease events both motivates investigation of biological factors underpinning phenotypic heterogeneity, and informs the selection of measures for clinical trials in posterior cortical atrophy.
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Doença de Alzheimer/patologia , Córtex Cerebral/patologia , Disfunção Cognitiva/patologia , Doença de Alzheimer/complicações , Estudos de Casos e Controles , Disfunção Cognitiva/complicações , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Testes NeuropsicológicosRESUMO
A young woman with systemic lupus erythematosus (SLE) developed recurrent enterovirus meningoencephalitis while taking prednisolone, azathioprine and rituximab. After reducing the immunosuppression, she developed a central nervous system (CNS) flare of SLE, with enterovirus still present in the cerebrospinal fluid (CSF). There are no evidence-based specific treatments for enterovirus encephalitis, but she responded well to intravenous immunoglobulin alongside pulsed methylprednisolone and rituximab. This case highlights the difficulties in managing people with co-existing infective and autoimmune conditions, especially if each affects the CNS. A viral infection and SLE flare can resemble one another clinically, although here the radiological differentiation of CNS lupus versus enterovirus encephalitis helped to guide the diagnosis.
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Infecções por Enterovirus/imunologia , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Meningoencefalite/imunologia , Azatioprina/uso terapêutico , Encefalite Viral/imunologia , Feminino , Humanos , Meningite Viral/imunologia , Prednisolona/uso terapêutico , Rituximab/uso terapêutico , Adulto JovemRESUMO
White matter hyperintensities (WMH) are often seen on MRI brain scans in frontotemporal dementia (FTD) due to progranulin (GRN) mutations, but their pathological correlates are unknown. We examined the histological changes underlying WMH in a patient with GRN mutation associated behavioral variant FTD. In vivo and cadaveric MRI showed progressive, asymmetric frontotemporal and parietal atrophy, and asymmetrical WMH predominantly affecting frontal mid-zones. We first performed segmentation and localization analyses of WMH present on cadaveric MRI FLAIR images, then selected five different brain regions directly matched to differing severities of WMH for histological analysis. We used immunohistochemistry to assess vascular pathology, degree of spongiosis, neuronal and axonal loss, TDP-43, demyelination and astrogliosis, and microglial burden and morphology. Brain regions with significant WMH displayed severe cortical and white matter pathology, and prominent white matter microglial activation and microglial dystrophy, but only mild axonal loss and minimal vascular pathology. Our study suggests that WMH in GRN mutation carriers are not secondary to vascular pathology. Whilst cortical pathology induced axonal degeneration could contribute to white matter damage, individuals with GRN mutations could develop selective white matter vulnerability and myelin loss due to chronic, regional microglial dysfunction arising from GRN haploinsufficiency.
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Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Demência Frontotemporal/fisiopatologia , Progranulinas/genética , Substância Branca/patologia , Feminino , Demência Frontotemporal/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagemRESUMO
Syphilis is a resurgent sexually transmitted infection in the UK that is disproportionately diagnosed in patients living with HIV, particularly in men who have sex with men. Syphilis appears to present differently in patients with HIV, particularly in those with severe immunosuppression. Progression to neurosyphilis is more common in HIV coinfection and can be asymptomatic, often for several years. The presentations of neurosyphilis vary but can include meningitis, meningovascular disease, general paresis and tabes dorsalis. There is debate about the circumstances in which to perform a lumbar puncture, and the current gold standard diagnostics have inadequate sensitivity. We recommend a pragmatic approach to lumbar punctures, interpreting investigations and deciding when to consider treatment with a neuropenetrative antibiotic regimen.
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Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Neurossífilis/complicações , Adulto , Diagnóstico Diferencial , Infecções por HIV/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Neurossífilis/diagnóstico , Neurossífilis/terapiaRESUMO
We discuss the assessment and differential diagnoses of a young adult Hungarian man with a 1-year history of a progressive and symmetric amyotrophic lateral sclerosis-like syndrome, along with irregular action tremor and stimulus-sensitive myoclonus of the arms. MR scan of the brain showed isolated cerebellar atrophy and formal neuropsychometric testing identified significant subclinical deficits in attention, processing speed and memory. We suspected a form of GM2 gangliosidosis, and white cell enzyme analysis showed markedly reduced enzymatic activity of ß-hexosaminidase A. Genetic testing subsequently revealed two heterozygous pathogenic mutations in the HEXA gene (c.1499delT p.(Leu500fs) and c.805G>A p.(Gly269Ser)), confirming the very rare diagnosis of adult-onset Tay-Sachs disease.
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Doença de Tay-Sachs/diagnóstico , Doença de Tay-Sachs/fisiopatologia , Adulto , Idade de Início , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Creatina Quinase/sangue , Diagnóstico Diferencial , Eletrocardiografia , Humanos , Imageamento por Ressonância Magnética , Masculino , Doença de Tay-Sachs/sangue , Tomografia Computadorizada por Raios XRESUMO
This is a rare presentation of brain tumour in the region of the lateral geniculate nucleus (LGN) presenting as a homonymous horizontal sectoranopia (HHS). The case highlights that subtle field defects can be asymptomatic and only detected by formal perimetry. Although homonymous sectoranopia is a rare form of visual field defect, it should be recognised as a potential manifestation of potentially significant intracranial pathology.
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New therapeutic approaches in Alzheimer's disease are urgently needed. The normal plasma protein, serum amyloid P component (SAP), is always present in cerebrospinal fluid (CSF) and in the pathognomonic lesions of Alzheimer's disease, cerebrovascular and intracerebral Abeta amyloid plaques and neurofibrillary tangles, as a result of its binding to amyloid fibrils and to paired helical filaments, respectively. SAP itself may also be directly neurocytotoxic. Here, in this unique study in Alzheimer's disease of the bis(d-proline) compound, (R)-1-[6-[(R)-2-carboxy-pyrrolidin-1-yl]-6-oxo-hexanoyl]pyrrolidine-2-carboxylic acid (CPHPC), we observed depletion of circulating SAP and also remarkable, almost complete, disappearance of SAP from the CSF. We demonstrate that SAP depletion in vivo is caused by CPHPC cross-linking pairs of SAP molecules in solution to form complexes that are immediately cleared from the plasma. We have also solved the structure of SAP complexed with phosphothreonine, its likely ligand on hyperphosphorylated tau protein. These results support further clinical study of SAP depletion in Alzheimer's disease and potentially other neurodegenerative diseases.
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Doença de Alzheimer/metabolismo , Ácidos Carboxílicos/administração & dosagem , Pirrolidinas/administração & dosagem , Componente Amiloide P Sérico/antagonistas & inibidores , Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Dicroísmo Circular , Cristalografia por Raios X , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Projetos Piloto , Conformação Proteica , Componente Amiloide P Sérico/líquido cefalorraquidiano , Componente Amiloide P Sérico/químicaRESUMO
OBJECTIVE: To investigate whether herpes simplex virus type 1 (HSV-1) infection was associated with rates of cognitive decline or whole brain atrophy among individuals from the Dominantly Inherited Alzheimer Network (DIAN). METHODS: Among two subsets of the DIAN cohort (age range 19.6-66.6 years; median follow-up 3.0 years) we examined (i) rate of cognitive decline (N = 164) using change in mini-mental state examination (MMSE) score, (ii) rate of whole brain atrophy (N = 149), derived from serial MR imaging, calculated using the boundary shift integral (BSI) method. HSV-1 antibodies were assayed in baseline sera collected from 2009-2015. Linear mixed-effects models were used to compare outcomes by HSV-1 seropositivity and high HSV-1 IgG titres/IgM status. RESULTS: There was no association between baseline HSV-1 seropositivity and rates of cognitive decline or whole brain atrophy. Having high HSV-1 IgG titres/IgM was associated with a slightly greater decline in MMSE points per year (difference in slope - 0.365, 95% CI: -0.958 to -0.072), but not with rate of whole brain atrophy. Symptomatic mutation carriers declined fastest on both MMSE and BSI measures, however, this was not influenced by HSV-1. Among asymptomatic mutation carriers, rates of decline on MMSE and BSI were slightly greater among those who were HSV-1 seronegative. Among mutation-negative individuals, no differences were seen by HSV-1. Stratifying by APOE4 status yielded inconsistent results. INTERPRETATION: We found no evidence for a major role of HSV-1, measured by serum antibodies, in cognitive decline or whole brain atrophy among individuals at high risk of early-onset AD.
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Doença de Alzheimer , Disfunção Cognitiva , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Simplexvirus , Doença de Alzheimer/genética , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imunoglobulina G , Imunoglobulina MRESUMO
Establishing preclinical models of Alzheimer's disease that predict clinical outcomes remains a critically important, yet to date not fully realized, goal. Models derived from human cells offer considerable advantages over non-human models, including the potential to reflect some of the inter-individual differences that are apparent in patients. Here we report an approach using induced pluripotent stem cell-derived cortical neurons from people with early symptomatic Alzheimer's disease where we sought a match between individual disease characteristics in the cells with analogous characteristics in the people from whom they were derived. We show that the response to amyloid-ß burden in life, as measured by cognitive decline and brain activity levels, varies between individuals and this vulnerability rating correlates with the individual cellular vulnerability to extrinsic amyloid-ß in vitro as measured by synapse loss and function. Our findings indicate that patient-induced pluripotent stem cell-derived cortical neurons not only present key aspects of Alzheimer's disease pathology but also reflect key aspects of the clinical phenotypes of the same patients. Cellular models that reflect an individual's in-life clinical vulnerability thus represent a tractable method of Alzheimer's disease modelling using clinical data in combination with cellular phenotypes.
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A 37-year-old female presented with ocular flutter and a transient rhombo-encephalitis following acute adenoviral kerato-conjunctivitis. Clinicians are made aware of the possibility of a transient encephalitic illness following adenoviral conjunctivitis.
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BACKGROUND: Type 2 diabetes is a risk factor for Alzheimer's disease (AD), and AD brain shows impaired insulin signalling. The role of peripheral insulin resistance on AD aetiopathogenesis in non-diabetic patients is still debated. Here we evaluated the influence of insulin resistance on brain glucose metabolism, grey matter volume and white matter lesions (WMLs) in non-diabetic AD subjects. METHODS: In total, 130 non-diabetic AD subjects underwent MRI and [18F]FDG PET scans with arterial cannula insertion for radioactivity measurement. T1 Volumetric and FLAIR sequences were acquired on a 3-T MRI scanner. These subjects also had measurement of glucose and insulin levels after a 4-h fast on the same day of the scan. Insulin resistance was calculated by the updated homeostatic model assessment (HOMA2). For [18F]FDG analysis, cerebral glucose metabolic rate (rCMRGlc) parametric images were generated using spectral analysis with arterial plasma input function. RESULTS: In this non-diabetic AD population, HOMA2 was negatively associated with hippocampal rCMRGlc, along with total grey matter volumes. No significant correlation was observed between HOMA2, hippocampal volume and WMLs. CONCLUSIONS: In non-diabetic AD, peripheral insulin resistance is independently associated with reduced hippocampal glucose metabolism and with lower grey matter volume, suggesting that peripheral insulin resistance might influence AD pathology by its action on cerebral glucose metabolism and on neurodegeneration.
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Doença de Alzheimer , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Fluordesoxiglucose F18 , Glucose , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de PósitronsRESUMO
An amendment to this paper has been published and can be accessed via the original article.
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BACKGROUND: Creutzfeldt-Jakob disease (CJD) is a rapidly progressive fatal neurodegenerative disorder. We report an unusual case of pathologically confirmed sporadic CJD developing in a HIV-positive patient but presenting with clinical and radiological features suggestive of variant CJD. CASE PRESENTATION: A 63-year-old man with chronic stable HIV developed progressive difficulties with decision-making, obsessive compulsive disorder and visual hallucinations over 3 months. CSF examination detected a weakly positive 14-3-3 protein, elevated S-100 protein, and siginificantly elevated total-Tau protein. Brain MRI revealed bilateral abnormal signal within the posterolateral thalami compatible with pulvinar sign. Further investigations revealed a negative tonsillar biospy and positive blood test consistent with variant CJD. However, prion protein genotyping detected MV heterozygosity at codon 129 and post-mortem histopathological examination was consistent with sporadic CJD. CONCLUSION: Although MRI findings were suggestive of variant CJD, the short residence in the UK and MV heterozygosity are aytpical, and the histopathological examination was consistent with sporadic CJD. With only two cases of HIV and sporadic CJD reported so far, the association of CJD with HIV remains unclear.
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Síndrome de Creutzfeldt-Jakob/complicações , Síndrome de Creutzfeldt-Jakob/diagnóstico , Infecções por HIV/complicações , Encéfalo/diagnóstico por imagem , Síndrome de Creutzfeldt-Jakob/patologia , Diagnóstico Diferencial , Evolução Fatal , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Interest is growing in the role of infectious agents in the pathogenesis of dementia, but current evidence is limited. We conducted a systematic review and meta-analysis to investigate the effect of any of eight human herpesviruses on development of dementia or mild cognitive impairment (MCI). We searched the Cochrane Library, Embase, Global Health, Medline, PsycINFO, Scopus, Web of Science, clinical trials registers and grey literature sources from inception to December 2017 for observational studies with cohort, case control or self-controlled designs, or randomised controlled trials of interventions against herpesviruses. Pooled effect estimates and 95% confidence intervals (CIs) were generated through random effects meta-analyses across studies with the same design, outcome, and virus type, method and site of measurement. We included 57 studies across various geographic settings. Past infection with herpesviruses, measured by IgG seropositivity, was generally not associated with dementia risk. A single cohort study rated moderate quality showed an association between varicella zoster virus reactivation (ophthalmic zoster) and incident dementia (HR 2.97; 95%CI, 1.89 to 4.66). Recent infection with, or reactivation of, herpes simplex virus type 1 or type 1/2 unspecified, cytomegalovirus and human herpes virus-6 measured by serum IgM, high titre IgG or clinical disease may be associated with dementia or MCI, though results were inconsistent across studies and overall evidence rated very low quality. Longitudinal population studies with robust repeated virus measurements taken sufficiently proximal to dementia onset are needed to establish whether, when and among whom herpesviruses affect dementia risk.
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Disfunção Cognitiva/virologia , Demência/virologia , Infecções por Herpesviridae/complicações , Disfunção Cognitiva/etiologia , Citomegalovirus/patogenicidade , Demência/etiologia , Herpesviridae/patogenicidade , Herpesvirus Humano 3/patogenicidade , Humanos , Ativação ViralRESUMO
BACKGROUND: Liraglutide is a glucagon-like peptide-1 (GLP-1) analogue currently approved for type 2 diabetes and obesity. Preclinical evidence in transgenic models of Alzheimer's disease suggests that liraglutide exerts neuroprotective effects by reducing amyloid oligomers, normalising synaptic plasticity and cerebral glucose uptake, and increasing the proliferation of neuronal progenitor cells. The primary objective of the study is to evaluate the change in cerebral glucose metabolic rate after 12 months of treatment with liraglutide in participants with Alzheimer's disease compared to those who are receiving placebo. METHODS/DESIGN: ELAD is a 12-month, multi-centre, randomised, double-blind, placebo-controlled, phase IIb trial of liraglutide in participants with mild Alzheimer's dementia. A total of 206 participants will be randomised to receive either liraglutide or placebo as a daily injection for a year. The primary outcome will be the change in cerebral glucose metabolic rate in the cortical regions (hippocampus, medial temporal lobe, and posterior cingulate) from baseline to follow-up in the treatment group compared with the placebo group. The key secondary outcomes are the change from baseline to 12 months in z scores for clinical and cognitive measures (Alzheimer's Disease Assessment Scale-Cognitive Subscale and Executive domain scores of the Neuropsychological Test Battery, Clinical Dementia Rating Sum of Boxes, and Alzheimer's Disease Cooperative Study-Activities of Daily Living) and the incidence and severity of treatment-emergent adverse events or clinically important changes in safety assessments. Other secondary outcomes are 12-month change in magnetic resonance imaging volume, diffusion tensor imaging parameters, reduction in microglial activation in a subgroup of participants, reduction in tau formation and change in amyloid levels in a subgroup of participants measured by tau and amyloid imaging, and changes in composite scores using support machine vector analysis in the treatment group compared with the placebo group. DISCUSSION: Alzheimer's disease is a leading cause of morbidity worldwide. As available treatments are only symptomatic, the search for disease-modifying therapies is a priority. If the ELAD trial is successful, liraglutide and GLP-1 analogues will represent an important class of compounds to be further evaluated in clinical trials for Alzheimer's treatment. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01843075 . Registration 30 April 2013.
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Doença de Alzheimer/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Glucose/metabolismo , Hipoglicemiantes/uso terapêutico , Liraglutida/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Atividades Cotidianas , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Ensaios Clínicos Fase II como Assunto , Cognição/efeitos dos fármacos , Método Duplo-Cego , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Liraglutida/efeitos adversos , Memória/efeitos dos fármacos , Estudos Multicêntricos como Assunto , Fármacos Neuroprotetores/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Reino UnidoRESUMO
BACKGROUND: Both cognitive tests and MRI-based measures have been suggested as outcomes in trials assessing disease-modifying therapies in Alzheimer's disease (AD). OBJECTIVE: To compare changes in longitudinal MRI measures with changes in performance on cognitive tests routinely used in AD clinical trials. METHOD: Fifty-two subjects from the placebo-arm of a clinical trial in mild-to-moderate AD had volumetric T(1)-weighted scans and cognitive tests including the Mini-Mental State Examination (MMSE), AD Assessment Scale-Cognitive Subscale, Disability Assessment for Dementia, AD Cooperative Study-Clinical Global Impression of Change and Clinical Dementia Rating at baseline and one-year later. Rates of brain atrophy and ventricular enlargement were measured using the boundary shift integral. Hippocampal (Hc) atrophy was calculated from manual volume measurements. The relationships between MRI and cognitive measures were investigated. RESULTS: Rates of brain atrophy and/or ventricular enlargement were correlated with declining performance on cognitive scales. The strongest association was between brain atrophy rate and MMSE decline (r = 0.59, p < 0.0001). Hc atrophy rate was not significantly correlated with any of the cognitive scales. CONCLUSION: The lack of correlation between Hc atrophy and cognitive scales may reflect a combination of: the extensive functional damage to the Hc by the time AD is clinically established, the greater influence of ongoing cortical degeneration, and errors in Hc outlining. The strong correlations between brain atrophy and ventricular enlargement, and cognitive scales probably reflect the correspondence between these measures of overall cerebral loss and global cognitive measures in the moderate stages of AD.
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Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Atrofia/patologia , Encéfalo/patologia , Transtornos Cognitivos/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Atrofia/etiologia , Atrofia/fisiopatologia , Biomarcadores/análise , Encéfalo/fisiopatologia , Mapeamento Encefálico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Progressão da Doença , Método Duplo-Cego , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Placebos , Valor Preditivo dos Testes , PrognósticoRESUMO
Gait disturbances are some of the earliest changes in dementia and their monitoring presents an opportunity for early diagnosis. The exact relationship between gait and well-established biomarkers of Alzheimer's disease (AD) remains to be clarified. In this study we compared gait-related measures with cerebrospinal fluid (CSF) markers of AD pathology. We recruited seventeen participants with mild AD in a multi-site study and performed gait assessment as well as lumbar punctures to obtain CSF. CSF Aß42/Aß40 and Aß42/Aß38 correlated positively with measures of variability (step time and step length) in the clinic-based assessments. This was driven by a negative relationship between gait variability and Aß40 and Aß38 but not Aß42.The amyloid ratios and gait variability measures were also associated with more severe functional impairment. We interpret these data as an indication that increasing amyloid production (i.e., increasing Aß40 and Aß38) is associated with diminishing cognitive-motor control of gait. These preliminary results suggest that the two amyloid ratios may be a marker of the earliest disturbances in the interplay between cognitive and motor control which characterize dementia.
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Atividades Cotidianas/psicologia , Doença de Alzheimer , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Transtornos Neurológicos da Marcha , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Doença de Alzheimer/psicologia , Feminino , Transtornos Neurológicos da Marcha/líquido cefalorraquidiano , Transtornos Neurológicos da Marcha/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos , Projetos Piloto , Reino UnidoRESUMO
BACKGROUND: The study investigated whether donepezil exerts symptomatic benefit in patients with posterior cortical atrophy (PCA), an atypical variant of Alzheimer's disease. METHODS: A single-centre, double-blind, placebo-controlled, cross-over clinical trial was performed to assess the efficacy of donepezil in patients with PCA. Each patient received either donepezil (5 mg once daily in the first 6 weeks and 10 mg once daily in the second 6 weeks) or placebo for 12 weeks. After a 2-week washout period, each patient received the other treatment arm during the following 12 weeks followed by another 2-week washout period. The primary outcome was the Mini-Mental State Examination (MMSE) at 12 weeks. Secondary outcome measures were five neuropsychological tests reflecting parieto-occipital function. Intention-to-treat analysis was used. For each outcome measure, carry-over effects were first assessed. If present, then analysis was restricted to the first 12-week period. Otherwise, the standard approach to the analysis of a 2 × 2 cross-over trial was used. RESULTS: Eighteen patients (13 females) were recruited (mean age 61.6 years). There was a protocol violation in one patient, who subsequently withdrew from the study due to gastrointestinal side effects. There was statistically significant (p < 0.05) evidence of a carry-over effect on MMSE. Therefore, the analysis of treatment effect on MMSE was restricted to the first 12-week period. Treatment effect at 6 weeks was statistically significant (difference = 2.5 in favour of donepezil, 95% CI 0.1 to 5.0, p < 0.05). Treatment effect at 12 weeks was close, but not statistically significant (difference = 2.0 in favour of donepezil, 95% CI -0.1 to 4.5, p > 0.05). There were no statistically significant treatment effects on any of the five neuropsychological tests, except for digit span at 12 weeks (higher by 0.5 digits in favour of placebo, 95% CI 0.1 to 0.9). Gastrointestinal side effects occurred most frequently, affecting 13/18 subjects (72%), and were the cause of study discontinuation in one subject. Nightmares and vivid dreams occurred in 8/18 subjects (44%), and were statistically more frequent during treatment with donepezil. CONCLUSIONS: In this small study, there was no statistically significant treatment effect of donepezil on the primary outcome measure (MMSE score at 12 weeks) in PCA patients, who appear to be particularly susceptible to the development of nightmares and vivid dreams when treated. TRIAL REGISTRATION: Trial registration: Current Controlled Trials ISRCTN22636071 . Retrospectively registered 19 May 2010.
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Doença de Alzheimer/tratamento farmacológico , Atrofia/tratamento farmacológico , Córtex Cerebral/patologia , Inibidores da Colinesterase/uso terapêutico , Donepezila/uso terapêutico , Idoso , Doença de Alzheimer/complicações , Atrofia/etiologia , Córtex Cerebral/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Testes Neuropsicológicos , Avaliação de Resultados em Cuidados de Saúde , Resultado do TratamentoRESUMO
INTRODUCTION: There is a need for a reliable, noninvasive biomarker for Alzheimer's disease (AD). We assessed whether short-latency afferent inhibition (SAI), a transcranial magnetic stimulation paradigm that assesses cholinergic circuits of the brain, could become such a biomarker. METHODS: Nineteen patients with AD underwent four SAI testing sessions. The timing of their usual donepezil dose was altered to create different cholinergic states for each session. This was compared to the SAI results from 20 healthy subjects. RESULTS: SAI was not able to distinguish the different cholinergic states assessed in our study. There appeared to be a diurnal variation in cholinergic function in the control group, which was not present in the AD cohort. DISCUSSION: SAI does not appear to have a role in diagnosis and assessment of AD patients. The loss of diurnal variation, however, warrants further investigation as it may provide further biochemical insights about AD.