RESUMO
BACKGROUND: This study reports the findings of the first large-scale Phase III investigator-driven clinical trial to slow the rate of cognitive decline in Alzheimer disease with a dihydropyridine (DHP) calcium channel blocker, nilvadipine. Nilvadipine, licensed to treat hypertension, reduces amyloid production, increases regional cerebral blood flow, and has demonstrated anti-inflammatory and anti-tau activity in preclinical studies, properties that could have disease-modifying effects for Alzheimer disease. We aimed to determine if nilvadipine was effective in slowing cognitive decline in subjects with mild to moderate Alzheimer disease. METHODS AND FINDINGS: NILVAD was an 18-month, randomised, placebo-controlled, double-blind trial that randomised participants between 15 May 2013 and 13 April 2015. The study was conducted at 23 academic centres in nine European countries. Of 577 participants screened, 511 were eligible and were randomised (258 to placebo, 253 to nilvadipine). Participants took a trial treatment capsule once a day after breakfast for 78 weeks. Participants were aged >50 years, meeting National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's disease Criteria (NINCDS-ADRDA) for diagnosis of probable Alzheimer disease, with a Standardised Mini-Mental State Examination (SMMSE) score of ≥12 and <27. Participants were randomly assigned to 8 mg sustained-release nilvadipine or matched placebo. The a priori defined primary outcome was progression on the Alzheimer's Disease Assessment Scale Cognitive Subscale-12 (ADAS-Cog 12) in the modified intention-to-treat (mITT) population (n = 498), with the Clinical Dementia Rating Scale sum of boxes (CDR-sb) as a gated co-primary outcome, eligible to be promoted to primary end point conditional on a significant effect on the ADAS-Cog 12. The analysis set had a mean age of 73 years and was 62% female. Baseline demographic and Alzheimer disease-specific characteristics were similar between treatment groups, with reported mean of 1.7 years since diagnosis and mean SMMSE of 20.4. The prespecified primary analyses failed to show any treatment benefit for nilvadipine on the co-primary outcome (p = 0.465). Decline from baseline in ADAS-Cog 12 on placebo was 0.79 (95% CI, -0.07-1.64) at 13 weeks, 6.41 (5.33-7.49) at 52 weeks, and 9.63 (8.33-10.93) at 78 weeks and on nilvadipine was 0.88 (0.02-1.74) at 13 weeks, 5.75 (4.66-6.85) at 52 weeks, and 9.41 (8.09-10.73) at 78 weeks. Exploratory analyses of the planned secondary outcomes showed no substantial effects, including on the CDR-sb or the Disability Assessment for Dementia. Nilvadipine appeared to be safe and well tolerated. Mortality was similar between groups (3 on nilvadipine, 4 on placebo); higher counts of adverse events (AEs) on nilvadipine (1,129 versus 1,030), and serious adverse events (SAEs; 146 versus 101), were observed. There were 14 withdrawals because of AEs. Major limitations of this study were that subjects had established dementia and the likelihood that non-Alzheimer subjects were included because of the lack of biomarker confirmation of the presence of brain amyloid. CONCLUSIONS: The results do not suggest benefit of nilvadipine as a treatment in a population spanning mild to moderate Alzheimer disease. TRIAL REGISTRATION: Clinicaltrials.gov NCT02017340, EudraCT number 2012-002764-27.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Nifedipino/análogos & derivados , Nootrópicos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/psicologia , Progressão da Doença , Método Duplo-Cego , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nifedipino/uso terapêutico , Resultado do TratamentoRESUMO
We evaluated 374 consecutive patients from May 2013 to April 2014 who underwent major cardiac surgery. Each patient had an interview and a neurological clinical examination during the rehabilitation period. Patients with possible peripheral nervous system (PNS) complications underwent further electrodiagnostic tests. Among 374 patients undergoing major heart surgery (coronary artery bypass grafting, valvular heart surgery, ascending aortic aneurysm repair) 23 (6.1 %) developed 34 new PNS complications. We found four brachial plexopathies; four carpal tunnel syndromes; five critical illness neuropathies; three worsening of pre-existing neuropathies; two involvement of X, one of IX and one of XII cranial nerves; three peroneal (at knee), one saphenous, two median (at Struthers ligament), six ulnar (at elbow) mononeuropathies; two meralgia parestheticas. Diabetes is a strong risk factor for PNS complications (p = 0.002); we could not find any other relationship of PNS complications with clinical conditions, demographic data (gender, age) or type of surgical intervention. The mononeuropathies of right arms can be related to ipsilateral vein cannulation; position of body and stretching from chest wall retraction may be the cause of mononeuropathies of left arms (more frequent); the use of saphenous vein and position of the limbs may be the cause of mononeuropathies of the legs; surgical and anesthetical procedures can injure cranial nerves; respiratory failure and infection during the first days after surgery can cause critical illness neuropathies. Careful preoperative assessment and intraoperative management may reduce the risk of long-term PNS complications after cardiac surgery.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Doenças do Sistema Nervoso Periférico/epidemiologia , Complicações Pós-Operatórias , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mononeuropatias/epidemiologia , PrevalênciaRESUMO
BACKGROUND: Neurodegenerative disorders such Alzheimer's disease (AD) are often characterized by senile plaques and neurofibrillary tangle. In addition, reactive astrogliosis, microglia activation and a chronic inflammation are found in AD brain. Activated microglia has been reported to express a large number of beta chemokines including monocyte chemoattractant protein-1 (MCP-1). The potential role of MCP-1 in AD pathogenesis is supported by the over expression of MCP-1 associated with an increase of amyloid deposition in transgenic mice. MCP-1 protein may be regulated by a single nucleotide polymorphism (SNP) occurring at position -2518 of the MCP-1 gene promoter. In this paper we correlated the A-2518G MCP-1 SNP distribution in three different populations: AD, control and MCI (mild cognitive impairment) population to evaluate whether this SNP might be a risk factor for AD or for MCI-AD conversion. MCP-1 plasma levels were also measured and correlated to the cognitive impairment (CIND) and AD risk. RESULTS: No differences in genotype distribution and allele frequencies of A-2518G MCP-1 SNP among AD patients, MCI subjects and controls were observed even after APOEe4 variation adjustment with logistic regression. However in MCI subjects, followed up for two years, this SNP appears to influence the progression of the disease; being the G allele slightly more frequent in MCI patients that developed AD. MCP-1 plasma levels were different among CIND (cognitive impairment but no dementia), AD and controls. The MCP-1 A-2518G promoter polymorphism did not affect MCP-1 plasma levels within the three populations. CONCLUSIONS: MCP-1 G allele did not affect the risk of AD, but slightly influenced MCI conversion to AD and MCP-1 plasma levels were increased in subjects with preclinical AD.
RESUMO
The early differentiation between Alzheimer's disease (AD) and frontal variant of frontotemporal dementia (fvFTD) is frequently difficult, albeit critical for the adequate management of patients and their caregivers. In order to assess the accuracy of CSF levels of beta-amyloid 1-42 (Aß), tau (τ) and Thr 181-phosphorilated tau (Pτ) in the early differentiation of AD from fvFTD, we designed a prospective study in which patients have been followed up for at least 2 years. Seventy-two patients with AD and 42 patients with fvFTD showed significantly different CSF levels of Pτ (increased in AD, p = 0.0001), Aß (reduced in AD, p = 0.03), and ratios of Pτ to Aß (p = 0.003). ROC analyses showed that the ratio Pτ/Αß is able to predict diagnosis with an AUC of 0.73 (optimal level being 0.16) corresponding to a sensitivity of 80% and a specificity of 68%. Our findings suggest that CSF metabolites may be the important tools in the early differential diagnosis between AD and fvFTD, albeit to be correlated with clinical, neuropsychological and bio imaging features.
Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico , Demência Frontotemporal/líquido cefalorraquidiano , Demência Frontotemporal/diagnóstico , Proteínas tau/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/metabolismo , Biomarcadores/líquido cefalorraquidiano , Diagnóstico Diferencial , Feminino , Demência Frontotemporal/metabolismo , Humanos , Masculino , Curva ROCRESUMO
OBJECTIVE: Studies correlating electroencephalographic (EEG) data and cognitive performance in Down's syndrome (DS) showed conflicting results. The aims of this study were to investigate the sources of EEG rhythms in adults with DS at three dimensional representation of current source density (CSD) using exact/standard Low Resolution Electromagnetic Tomography (e/sLORETA), and their correlation with cognitive performance. METHODS: Twenty-five adults with DS underwent a neuropsychological battery and 5 min of resting, eye-closed 29-channel EEG were recorded. After e/sLORETA analysis, data were compared with those from age and gender-matching control subjects as following: absolute and relative power in delta (1-3 Hz), theta (4-7 Hz), alpha1 (8-9 Hz), alpha2 (10-12 Hz), beta1 (13-18 Hz), beta2 (19-21 Hz), beta3 (22-30 Hz); alpha and theta bands adjusted to individual alpha peak frequency (IAF). Current source activities in DS group in regions showing significant differences compared with controls underwent correlation analysis with psychometric scores. RESULTS: In DS, IAF was shifted to lower frequencies and correlated positively with Wechsler Adult Intelligence Scale and Mini-Mental State examination. Compared with controls, DS showed increased CSD in: theta, alpha-1, and beta1 classical bands and in IAF-adjusted bands, while relative alpha2 was decreased. A negative correlation between cognitive performance and theta/alpha CSD in the right frontal lobe and right posterior cingulate cortex was found. The relative alpha2 correlated positively with cognitive tests. CONCLUSIONS: Increased CSD in DS, correlating with cognitive performance, for both slow and fast rhythms suggests involving of cortical and subcortical mechanisms. LORETA might be useful for objective measure of cognitive decline in DS.
Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Síndrome de Down/fisiopatologia , Adulto , Idoso , Transtornos Cognitivos/etiologia , Síndrome de Down/complicações , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes NeuropsicológicosRESUMO
BACKGROUND: Despite being the fastest growing and the most cognitively impaired age group, the oldest olds are under-represented in clinical research. The purpose of this study was to describe the design, methods, and baseline characteristics of the survey population and investigate possible differences in demographic, cognitive, functional, and behavioral characteristics between oldest old with and without any performance on cognitive tests and between oldest old alive and those deceased prior to the interview. METHODS: The Monzino 80-plus Study is a prospective door-to-door population-based survey among 80 years or older residents in the municipalities in the province of Varese, Italy. Dementia cases were identified with a one-phase design. Trained psychologists interviewed both the subject and a proxy informant. The interview included a comprehensive standardized questionnaire together with an array of rating scales and a multidomain cognitive battery to assess cognitive and functional ability, behavioral disturbances and mood. RESULTS: Information was available for 2,139 of the 2,428 registered individuals aged 80 years or older. Main baseline characteristics of the population are reported and discussed. In comparison with those living, elderly persons who had died before the first visit were older, had twice the rate of institutionalization, poorer cognitive performance and competence, and significantly greater instrumental and basic functional disability. The percentage of elderly persons, alive at baseline, without Mini-Mental State Examination rose rather evenly with age. Moreover, they had significantly worse cognitive competence and functional ability, and reported higher prevalences of depressive symptoms and problem behaviors than those with Mini-Mental State Examination. CONCLUSIONS: Prospective investigation of a large population of oldest old can contribute significantly to understanding the relations between age, cognitive decline, and dementia occurrence. Use of informant-based instruments in surveys in the oldest old is crucial in assessing everyday functioning and changes, especially in participants with no cognitive test performance available. Failure to include information on deceased elderly would underestimate, increasingly with age, the prevalence of cognitive and functional disability in the elderly population.
Assuntos
Demência/diagnóstico , Demência/epidemiologia , Avaliação Geriátrica , Atividades Cotidianas , Idoso de 80 Anos ou mais , Sintomas Comportamentais/etiologia , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/etiologia , Planejamento em Saúde Comunitária , Demência/complicações , Pessoas com Deficiência , Feminino , Humanos , Itália/epidemiologia , Estilo de Vida , Masculino , Testes Neuropsicológicos , Prevalência , Estudos Retrospectivos , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: The authors assessed whether brain changes detected by diffusion tensor (DT) MRI can improve the understanding of structural damage in Alzheimer's disease (AD) and are associated with different risks of conversion to AD in amnestic mild cognitive impairment (aMCI). METHODS: Twenty-one aMCI patients, 21 AD patients and 20 healthy subjects underwent conventional and DT MRI at baseline. All subjects were clinically followed up over 2 years; at the end of follow-up, aMCI were grouped into converters to AD (aMCI-C) and non-converters (aMCI-NC). The mean diffusivity (MD) and fractional anisotropy (FA) were obtained from total grey matter (GM) and white matter (WM), and from several GM and WM regions of interest (ROIs). On T1-weighted images, normalised volumes of the whole brain (NBV), GM (NGMV) and WM were measured. RESULTS: A significant 'trend' of worsening with a trajectory 'normal/aMCI/AD' was found for NBV and NGMV, total GM and WM MD, total WM FA, as well as for diffusivity abnormalities in several GM and WM ROIs, mainly located in posterior brain regions. aMCI-C had GM and WM changes similar to those seen in AD, whereas aMCI-NC showed a DT MRI pattern similar to that of healthy subjects. DT MRI metrics that better distinguished aMCI-C from aMCI-NC were MD of total GM and WM, hippocampi, anterior insulae, frontal and parietal WM, occipital GM and WM, and FA of temporal WM. Volumetric variables were not able to distinguish the two aMCI subgroups (aMCI-C and aMCI-NC). CONCLUSIONS: Subtle brain diffusivity changes occur from the prodromal stages of AD, mainly in posterior brain regions, and spread over the course of the disease to involve the frontal lobe. In aMCI, the severity of microstructural damage within and beyond the medial temporal lobe is associated with an increased short-term risk to develop AD.
Assuntos
Doença de Alzheimer/patologia , Infarto da Artéria Cerebral Média/patologia , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/psicologia , Amnésia/etiologia , Amnésia/psicologia , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Infarto da Artéria Cerebral Média/complicações , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , SoftwareRESUMO
In a neuropsychological assessment, each test aims at measuring a single cognitive function. However, test performance depends on an interconnected system of cognitive functions and individual characteristics. For a better understanding of cognitive deficits, it is fundamental to recognize this complexity and study the relationships between test performances. This study aims to evaluate complexity in neuropsychological assessment through network analysis (NA) in 165 healthy older adults, 191 patients with Alzheimer's disease (AD), and 129 patients with vascular encephalopathy (VaE). NA is a flexible method to explore different domains where many variables are correlated with each other, and the relationships are key for understanding the domains. We included general aspects of individual differences (i.e., age, sex, years of education) and the raw scores of a clinically used neuropsychological battery in the network. Healthy subjects showed a segregated pattern, suggesting a good specificity of each test in measuring a specific cognitive function. Moreover, the scores were related to age and education. In the patient groups, the identified patterns changed in a consistent manner, showing less specificity and new relationships between the various tests, thereby reducing the impact of age and education on the performance. In particular, AD patients showed worse performance on the tests but also a different balance between different tasks, suggesting a reorganization of the cognitive system and not a mere decline. These results provide a new perspective in looking at the complexity of cognitive function assessment.
Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Disfunção Cognitiva , Idoso , Doença de Alzheimer/diagnóstico , Cognição , Disfunção Cognitiva/diagnóstico , Humanos , Testes NeuropsicológicosRESUMO
Conceptual knowledge is supported by multiple semantic systems that are specialized for the analysis of different properties associated with object concepts. Various types of semantic association between concrete concepts-categorical (CA), encyclopedic (EA), functional (FA), and visual-encyclopedic (VEA) associations-were tested through a new picture-to-picture matching task (semantic association task, SAT). Forty individuals with Alzheimer's disease (AD), 13 with behavioral variant of frontotemporal dementia (bv-FTD), 6 with primary progressive aphasia (PPA), and 37 healthy participants were tested with the SAT. Within-group comparisons highlighted a global impairment of all types of semantic association in bv-FTD individuals but a disproportionate impairment of EA and FA, with relative sparing of CA and VEA, in AD individuals. Single-case analyses detected dissociations in all dementia groups. Conceptual knowledge can be selectively impaired in various types of neurodegenerative disease on the basis of the specific cognitive process that is disrupted.
Assuntos
Doença de Alzheimer/fisiopatologia , Afasia Primária Progressiva/fisiopatologia , Conhecimentos, Atitudes e Prática em Saúde , Testes Neuropsicológicos/estatística & dados numéricos , Semântica , Idoso , Feminino , Demência Frontotemporal/fisiopatologia , Humanos , MasculinoRESUMO
Sixty-nine dyads of patients with Alzheimer's disease and primary caregivers have been followed up for 1 year to evaluate cognitive (Mini-Mental State Examination), functional (Instrumental Activities of Daily Living), and behavioral (Neuropsychiatric Inventory) decline of patient in relation to burden (Caregiver Burden Inventory), stress (Relative Stress Scale), anxiety (State-Trait Anxiety Inventory Y), and depression (Beck Depression Inventory) reported by the caregivers. After 1 year of observation, cognitive and functional scores worsened while behavioral problems remained unchanged and relatively mild in patients. After 1 year, caregivers' scores of scales of anxiety and depression decreased significantly, while stress scores remained unchanged and burden slightly increased. In our opinion, the unexpected improvement in psychological situation of caregivers may be mainly due to educational interventions focused on knowledge of the disease with a particular attention directed toward emotional support and individual needs.
Assuntos
Doença de Alzheimer/enfermagem , Ansiedade/psicologia , Cuidadores/psicologia , Efeitos Psicossociais da Doença , Depressão/psicologia , Estresse Psicológico/psicologia , Adaptação Psicológica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica/estatística & dados numéricosRESUMO
BACKGROUND: The latest developments in Lewy Body Dementia (DLB) raise some controversies on clinical features, neuroimaging and therapy. The aim of our study is to determine clinical, neuropsychological, neuroimaging and EEG profile of DLB through retrospective and prospective data of 102 patients. METHODS: data were collected with an analytical form that was developed by an expertise of neurologists. RESULTS: DLB represented 4.8% of the dementia population, with no sex difference. Family history of dementia was common (24.5%), while familiarity for parkinsonism was rare (4.9%). Cognitive disturbances were the predominant clinical presentation at onset (49%), followed by behavioral symptoms (29.4%) and parkinsonism (21.6%). Clinical features at consultation were: memory disturbances (almost all cases), symmetrical (68.6%) or asymmetrical (18.6%) parkinsonism, cognitive fluctuations (49%), visuospatial deficits (53.9%), and visual hallucinations (44.1%). Autonomic signs were present in a third of the cases, while sleep disorders were present in 44.1%. Some clinical response to antiparkinsonian drugs was evident in half of the cases. MRI, SPET, EEG and Neuropsychiatric Inventory data were available in a subgroup of patients. CONCLUSIONS: Most of our data were in accordance with the previous literature. However, some data underline the relationship between DLB, Alzheimer's and Parkinson's disease.
Assuntos
Doenças do Sistema Nervoso Autônomo/epidemiologia , Sintomas Comportamentais/epidemiologia , Doença por Corpos de Lewy/complicações , Doença por Corpos de Lewy/psicologia , Transtornos da Percepção/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Diagnóstico por Imagem , Eletroencefalografia , Feminino , Hospitais Psiquiátricos , Humanos , Itália , Doença por Corpos de Lewy/diagnóstico , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Prevalência , Psicotrópicos/uso terapêutico , Estudos RetrospectivosRESUMO
BACKGROUND: A secure attachment style could promote more intimacy in romantic relationships, while an insecure attachment style could be correlated with less positive romantic relationships in adulthood. Numerous studies have noted that a secure attachment to parents was correlated with lower levels of aggression, whereas insecure attachments were associated with higher levels of aggression. We aimed to investigate the role of the attachment system as a mediator of the expression of aggressiveness during adolescence. Specifically, we considered that the attachment to parents and peers could influence one's attachment to a romantic partner. METHODS: We empirically tested whether there were relationships of parent and peer attachment on aggressiveness mediated by romantic attachment style. Participants of the study included 411 students. RESULTS: Results indicated that for males an insecure father-child attachment style seems to be associated with higher levels of anxiety and avoidance in romantic attachments and then with aggressiveness. For females, an insecure mother-child attachment style seems to be associated with higher levels of aggressiveness. CONCLUSION: The attachment to parents and to peers plays a key role in defining romantic attachment according to gender, and these dimensions in turn tend to affect the levels of aggressiveness.
RESUMO
AIM: To determine the applicability and psychometric properties of the Italian version of the Disability Assessment of Dementia scale (DAD-I) in a community-residing population with early-stage Alzheimer's disease (AD). METHODS: The DAD-I was administered to the primary caregivers of 159 patients (mean age +/- SD 77.1 +/- 5.2) with mild AD (mean Mini Mental State Examination, MMSE, +/- SD 23.1 +/- 2.2). RESULTS: The DAD-I showed excellent internal consistency reliability (Cronbach's alpha = 0.92) and good construct validity. The DAD-I score was not significantly associated with gender, education and presumed duration of the illness, and had a low negative correlation with age. The DAD-I score correlated moderately with the traditional Instrumental Activities of Daily Living and Activities of Daily Living scales, respectively, with r = 0.53 and r = 0.54 (p < 0.0001). Relatively low, but statistically significant correlations (r ranging between 0.21 and 0.31) with the MMSE were also found. CONCLUSION: The DAD-I was found to be a reliable and valid instrument to assess functional disability in community-dwelling Italian subjects with early-stage AD.
Assuntos
Doença de Alzheimer/diagnóstico , Avaliação da Deficiência , Inquéritos e Questionários , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaRESUMO
The genetic form of Alzheimer disease (FAD) accounts for about 5% of total Alzheimer disease (AD) cases, and the discovery of FAD-linked genes has shed new light on AD pathogenic mechanism. The presenilins genes (PSEN-1 and PSEN-2) carry the large majority of FAD-linked mutations. Here, we report an Italian kindred with FAD and PSEN-1 double mutation E318G+G394V that clearly cosegregates with the pathology. The E318G mutation has not an assessed pathogenic function, but some data have highlighted a role as a risk factor for AD in a predisposed familiar background. The G394V mutation was still described in association to an AD case with reported (but not demonstrated) familiar cosegregation. In an attempt to better characterize the biochemical effect of this double mutation, we assessed A beta(1-40) and A beta(1-42) concentrations in conditioned media from primary skin fibroblasts obtained from AD-affected and healthy family members. We did not find any modification of the A beta(1-42)/A beta(1-40) ratio, suggesting that this double mutation might be involved in early-onset AD etiopathogenesis by affecting a PSEN-1 function other than gamma-secretase activity.
Assuntos
Doença de Alzheimer/genética , Presenilina-1/genética , Adulto , Idade de Início , Precursor de Proteína beta-Amiloide , Apolipoproteínas E , Testes Genéticos , Genótipo , Humanos , Itália , Masculino , Pessoa de Meia-Idade , MutaçãoRESUMO
The "frontal aging hypothesis" predicts that brain senescence affects predominantly the prefrontal regions. Preliminary evidence has recently been gathered in favour of an age-related change in a typically frontal process, i.e. decision making, using the Iowa Gambling Task (IGT), but overall findings have been conflicting. Following the traditional scoring method, coupled with a qualitative analysis, in the present study we compared IGT performance of 40 young (mean age: 27.9+/-4.7) and 40 old (mean age: 65.4+/-8.6) healthy adults and of 18 patients affected by frontal lobe dementia of mild severity (mean age: 65.1+/-7.4, mean MMSE score: 24.1+/-3.9). Quantitative findings support the notion that decision making ability declines with age; moreover, it approximates the impairment observed in executive dysfunction due to neurodegeneration. Results of the qualitative analysis did not reach statistical significance for the motivational and learning decision making components considered, but approached significance for the attentional component for elderly versus young normals, suggesting a possible decrease in the ability to maintain sustained attention during complex and prolonged tasks as the putative deficit underlying impaired decision making in normal aging.
Assuntos
Envelhecimento/fisiologia , Aptidão , Tomada de Decisões , Demência/fisiopatologia , Fatores Etários , Idoso , Atenção , Demência/diagnóstico , Feminino , Jogo de Azar , Humanos , Aprendizagem , Masculino , Motivação , Testes NeuropsicológicosRESUMO
A link between cholesterol and Alzheimer's disease (AD) had been suggested. Hydroxy-methylglutaryl-coenzyme A reductase (HMGCR) is the rate limiting enzyme in the synthesis of cholesterol. A single nucleotide polymorphism (SNP) in the promoter of this gene, never described in Italian AD population, was investigated in case-control studies. Genotype distribution and allele frequency in two groups of AD patients and non demented controls were investigated. A cohort of AD patients were also followed up for 2 years, cognitive performances recorded and a possible influence of this SNP on the disease progression was tested. The CC genotype of the HMGCR gene was associated with a reduced risk of AD. Conversely the A allele of this polymorphism was over represented in AD patients. The presence of the A allele was also associated with an accelerated cognitive deterioration in AD patients followed up for 2 years. However, transfection experiments showed that this polymorphism did not directly influence functional activity in luciferase reporter gene assays. This polymorphism of the HMGCR gene appears to be linked to both AD risk and disease progression. Present findings reinforce the notion that abnormal regulation of cholesterol metabolism is a key factor in the pathogenesis of the disease.
Assuntos
Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Hidroximetilglutaril-CoA Redutases/genética , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Astrócitos/citologia , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Colesterol/metabolismo , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/genética , Progressão da Doença , Frequência do Gene , Predisposição Genética para Doença/epidemiologia , Genótipo , Humanos , Neoplasias Hepáticas , Regiões Promotoras Genéticas/genética , Fatores de Risco , TransfecçãoRESUMO
BACKGROUND: Executive dysfunction in Alzheimer's disease (AD) has been recently recognized as an early and prominent clinical sign. The Tower of London (ToL), a task specifically devised to test executive functions of visuospatial planning and problem solving, has frequently been used in neuropsychological experiments, but rarely in the clinical ground. METHODS: One hundred and sixty-one AD patients and 212 nondemented healthy controls were administered a simplified ToL version. RESULTS: AD patients were significantly impaired (p < 0.0001) in all ToL scores and in the total execution time. The 'accuracy' score of ToL at a cut off of Assuntos
Doença de Alzheimer/epidemiologia
, Transtornos Cognitivos/diagnóstico
, Transtornos Cognitivos/epidemiologia
, Transtornos da Percepção/diagnóstico
, Transtornos da Percepção/epidemiologia
, Percepção Espacial/fisiologia
, Percepção Visual/fisiologia
, Idoso
, Doença de Alzheimer/diagnóstico
, Feminino
, Humanos
, Masculino
, Testes Neuropsicológicos
, Prevalência
, Índice de Gravidade de Doença
RESUMO
BACKGROUND: The expression of vascular endothelial growth factor (VEGF) represents one potential mechanism whereby vascular and Alzheimer's disease (AD) pathologies are related. The authors investigated whether AD cases, especially those having a rapid cognitive decline, more commonly carried a functional promoter gene variant for VEGF (-2578C/A) and showed elevated plasma levels of Vegf. In addition, the authors investigated whether patterns of association also were found for mild cognitive impairment (MCI) and conversion from MCI to AD. METHODS: Group 1 included 317 AD cases and 320 unaffected control subjects. Group 2 included 113 MCI patients and 130 control subjects. Plasma levels of Vegf were measured by chemiluminescence for a subset of group 1. Genotype determinations were made for all subjects. FINDINGS: The VEGF AA genotype was associated with an increased risk of developing AD (OR = 1.616, p = 0.046). This genotype also was associated with an accelerated cognitive decline in APOE small epsilon4 positive patients with AD (AA vs. CC OR = 6.5, p = 0.04). The VEGF AA genotype was a risk factor for MCI (OR = 2.5, p = 0.037) and MCI conversion to AD in APOE small epsilon4+ (OR = 6.5, CI = 2.014-20.980; p = 0.002). Vegf plasma levels were higher in patients with AD than controls (230 pg/mL vs. 42 pg/mL), and were even higher in those patients with a fast cognitive decline and the APOE epsilon4 allele. INTERPRETATION: Modulation of VEGF expression is a potential mechanism associated with the risk of developing AD and its clinical deterioration.
Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Transtornos Cognitivos/sangue , Transtornos Cognitivos/genética , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Fenótipo , Índice de Gravidade de DoençaRESUMO
Previous studies suggest that genetic variants in CHRNA7, which encodes for the major subunit of the acetylcholine receptor (α7-nAChR), are associated with the clinical response to cholinesterase inhibitors (ChEI) in Alzheimer's disease (AD) patients. We sought to replicate the association of two SNPs in the CHRNA7 gene, rs6494223 and rs8024987, with response to ChEI treatment in an Italian cohort of 169 AD patients, further extending the study to gene-level analysis. None of the tested variants was associated with clinical response. However, rs6494223 showed a consistent effect direction (ORâ=â1.4; pâ=â0.17), which after meta-analysis with previous study yielded a significant result (ORâ=â1.57, pâ=â0.02, I2â=â0%).
Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Nootrópicos/uso terapêutico , Receptor Nicotínico de Acetilcolina alfa7/genética , Idoso , Doença de Alzheimer/genética , Feminino , Humanos , Itália , Masculino , Polimorfismo de Nucleotídeo Único/genética , Resultado do TratamentoRESUMO
Increased levels of alpha-1-antichymotrypsin (ACT), a protease inhibitor and an acute phase protein, have been found in the brain and peripheral blood of patients with Alzheimer's disease (AD). Patients from northern Italy with a clinical diagnosis of probable AD, and patients with early onset AD (EOAD) from UK with AD neuropathological diagnosis were genotyped for a new polymorphism in the promoter region of the ACT gene which has been shown to affect ACT expression. A subset of patients with clinical AD from northern Italy was also followed up for 2 years and monitored for cognitive decline. The ACT TT promoter genotype was associated with an increased risk of EOAD independently from the presence of the apolipoprotein E (APOE) epsilon 4 allele. After manifestation of the disease the ACT TT genotype was also associated with faster cognitive decline in patients with the APOE allele epsilon 4. The ACT gene appears to influence the early clinical development of the disease, and the interaction of the ACT and APOE genes affects clinical progression of AD.