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Recent evidence indicates that measures from cerebrospinal fluid, MRI scans and cognitive testing obtained from cognitively normal individuals can be used to predict likelihood of progression to mild cognitive impairment several years later, for groups of individuals. However, it remains unclear whether these measures are useful for predicting likelihood of progression for an individual. The increasing focus on early intervention in clinical trials for Alzheimer's disease emphasizes the importance of improving the ability to identify which cognitively normal individuals are more likely to progress over time, thus allowing researchers to efficiently screen participants, as well as determine the efficacy of any treatment intervention. The goal of this study was to determine which measures, obtained when individuals were cognitively normal, predict on an individual basis, the onset of clinical symptoms associated with a diagnosis of mild cognitive impairment due to Alzheimer's disease. Cognitively normal participants (n = 224, mean baseline age = 57 years) were evaluated with a range of measures, including: cerebrospinal fluid amyloid-ß and phosphorylated-tau, hippocampal and entorhinal cortex volume, cognitive tests scores and APOE genotype. They were then followed to determine which individuals developed mild cognitive impairment over time (mean follow-up = 11 years). The primary outcome was progression from normal cognition to the onset of clinical symptoms of mild cognitive impairment due to Alzheimer's disease at 5 years post-baseline. Time-dependent receiver operating characteristic analyses examined the sensitivity and specificity of individual measures, and combinations of measures, as predictors of the outcome. Six measures, in combination, were the most parsimonious predictors of transition to mild cognitive impairment 5 years after baseline (area under the curve = 0.85; sensitivity = 0.80, specificity = 0.75). The addition of variables from each domain significantly improved the accuracy of prediction. The incremental accuracy of prediction achieved by adding individual measures or sets of measures successively to one another was also examined, as might be done when enrolling individuals in a clinical trial. The results indicate that biomarkers obtained when individuals are cognitively normal can be used to predict which individuals are likely to develop clinical symptoms at 5 years post-baseline. As a number of the measures included in the study could also be used as subject selection criteria in a clinical trial, the findings also provide information about measures that would be useful for screening in a clinical trial aimed at individuals with preclinical Alzheimer's disease.
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Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Idoso , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Compostos de Anilina/farmacocinética , Apolipoproteínas E/genética , Encéfalo/efeitos dos fármacos , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/genética , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Curva ROC , Tiazóis/farmacocinética , Fatores de Tempo , Proteínas tau/líquido cefalorraquidianoRESUMO
This study evaluated the utility of baseline and longitudinal magnetic resonance imaging (MRI) measures of medial temporal lobe brain regions collected when participants were cognitively normal and largely in middle age (mean age 57 years) to predict the time to onset of clinical symptoms associated with mild cognitive impairment (MCI). Furthermore, we examined whether the relationship between MRI measures and clinical symptom onset was modified by apolipoprotein E (ApoE) genotype and level of cognitive reserve (CR). MRI scans and measures of CR were obtained at baseline from 245 participants who had been followed for up to 18 years (mean follow-up 11 years). A composite score based on reading, vocabulary, and years of education was used as an index of CR. Cox regression models showed that lower baseline volume of the right hippocampus and smaller baseline thickness of the right entorhinal cortex predicted the time to symptom onset independently of CR and ApoE-É4 genotype, which also predicted the onset of symptoms. The atrophy rates of bilateral entorhinal cortex and amygdala volumes were also associated with time to symptom onset, independent of CR, ApoE genotype, and baseline volume. Only one measure, the left entorhinal cortex baseline volume, interacted with CR, such that smaller volumes predicted symptom onset only in individuals with lower CR. These results suggest that MRI measures of medial temporal atrophy, ApoE-É4 genotype, and the protective effects of higher CR all predict the time to onset of symptoms associated with MCI in a largely independent, additive manner during the preclinical phase of Alzheimer's disease.
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Doença de Alzheimer/diagnóstico , Tonsila do Cerebelo/patologia , Apolipoproteínas E/genética , Disfunção Cognitiva , Reserva Cognitiva/fisiologia , Córtex Entorrinal/patologia , Hipocampo/patologia , Imageamento por Ressonância Magnética/métodos , Idoso , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Apolipoproteína E4 , Atrofia/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sintomas Prodrômicos , PrognósticoRESUMO
Accurate assessment of cognitive impairment requires comparison of cognitive performance in individuals to performance in a comparable healthy normative population. Few prior studies have included a large number of black participants and few have excluded participants from the normative sample with subclinical/latent neurological disease or dementia. This study provides age, race, and education-specific normative data for 8 cognitive tests derived from 320 black and 392 white participants aged 61 to 82 years (mean 71 y) in the Atherosclerosis Risk in Communities (ARIC) study without clinical or subclinical/latent neurological disease. Normative data are provided for the Delayed Word Recall Test, Logical Memory Parts I and II, the Word Fluency Test, Animal Naming, the Trail Making Test Parts A and B and the Digit Symbol Substitution Test. Age, race, and education-specific mean and -1.5 SD scores are given in tabular form and graphically, as well as regression-based equations to derive adjusted score cut-points. These robust normative data should enhance comparison across studies of cognitive aging, where these measures are widely used, and improve interpretation of performance on these tests for the diagnosis of cognitive impairment not only within the ARIC cohort, but also among older blacks and whites with similar demographics.
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Aterosclerose/diagnóstico , Aterosclerose/etnologia , Negro ou Afro-Americano/etnologia , Testes Neuropsicológicos/normas , Características de Residência , População Branca/etnologia , Negro ou Afro-Americano/psicologia , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/psicologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , População Branca/psicologiaRESUMO
BACKGROUND: Although controversial, failing to consider the gravitational effects of head elevation on cerebral perfusion is speculated to increase susceptibility to rare, but devastating, neurologic complications after shoulder surgery in the beach chair position (BCP). We hypothesized that patients in the BCP have diminished cerebral blood flow autoregulation than those who undergo surgery in the lateral decubitus position (LDP). A secondary aim was to examine whether there is a relationship between patient positioning during surgery and postoperative cognition or serum brain injury biomarker levels. METHODS: Patients undergoing shoulder surgery in the BCP (n = 109) or LDP (n = 109) had mean arterial blood pressure (MAP) and regional cerebral oxygen saturation (rScO2) monitored with near-infrared spectroscopy. A continuous, moving Pearson correlation coefficient was calculated between MAP and rScO2, generating the variable cerebral oximetry index (COx). When MAP is in the autoregulated range, COx approaches zero because there is no correlation between cerebral blood flow and arterial blood pressure. In contrast, when MAP is below the limit of autoregulation, COx is higher because there is a direct relationship between lower arterial blood pressure and lower cerebral blood flow. Thus, diminished autoregulation would be manifest as higher COx. Psychometric testing was performed before surgery and then 7 to 10 days and 4 to 6 weeks after surgery. A composite cognitive outcome was determined as the Z-score. Serum S100ß, neuron-specific enolase, and glial fibrillary acidic protein were measured at baseline, after surgery, and on postoperative day 1. RESULTS: After adjusting for age and history of hypertension, COx (P = 0.035) was higher and rScO2 lower (P < 0.0001) in the BCP group than in the LDP group. After adjusting for baseline composite cognitive outcome, there was no difference in Z-score 7 to 10 days (P = 0.530) or 4 to 6 weeks (P = 0.202) after surgery between the BCP and the LDP groups. There was no difference in serum biomarker levels between the 2 position groups CONCLUSIONS: : Compared with patients in the LDP, patients undergoing shoulder surgery in the BCP are more likely to have higher COx indicating diminished cerebral autoregulation and lower rScO2. There were no differences in the composite cognitive outcome between the BCP and the LDP groups after surgery after accounting for baseline Z-score.
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Lesões Encefálicas/sangue , Circulação Cerebrovascular , Transtornos Cognitivos/etiologia , Homeostase , Procedimentos Ortopédicos/métodos , Posicionamento do Paciente/métodos , Complicações Pós-Operatórias/etiologia , Ombro/cirurgia , Adulto , Idoso , Anestesia , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Segurança do Paciente , Assistência Perioperatória , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/psicologia , Decúbito DorsalRESUMO
Studies of long-term cognitive change should account for the potential effects of education on the outcome, since some studies have demonstrated an association of education with dementia risk. Evaluating cognitive change is more ideal than evaluating cognitive performance at a single time point, because it should be less susceptible to confounding. In this analysis of 14,020 persons from a US cohort study, the Atherosclerosis Risk in Communities (ARIC) Study, we measured change in performance on 3 cognitive tests over a 20-year period, from ages 48-67 years (1990-1992) through ages 70-89 years (2011-2013). Generalized estimating equations were used to evaluate the association between education and cognitive change in unweighted adjusted models, in models incorporating inverse probability of attrition weighting, and in models using cognitive scores imputed from the Telephone Interview for Cognitive Status for participants not examined in person. Education did not have a strong relationship with change in cognitive test performance, although the rate of decline was somewhat slower among persons with lower levels of education. Methods used to account for selective dropout only marginally changed these observed associations. Future studies of risk factors for cognitive impairment should focus on cognitive change, when possible, to allow for reduction of confounding by social or cultural factors.
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Transtornos Cognitivos/etiologia , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Escolaridade , Feminino , Seguimentos , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Testes Neuropsicológicos , Pacientes Desistentes do Tratamento , Fatores de Risco , Fatores de TempoRESUMO
BACKGROUND: The time that red cell units are stored before transfusion may be associated with postoperative complications, although the evidence is conflicting. However, the association between the length of red cell unit storage and postoperative delirium has not been explored. We hypothesized that the length of storage of transfused red cell units would be associated with delirium after cardiac surgery. METHODS: We conducted a case-control study in which patients undergoing coronary artery bypass, valve, or ascending aorta surgery with cardiopulmonary bypass at Johns Hopkins from 2005 to 2011 were eligible for inclusion. Patients were excluded if they did not receive red cell units, received >4 red cell units during hospitalization, received any transfusion after the first postoperative day, or received red cell units that were not exclusively stored for ≤14 days or >14 days. Eighty-seven patients met transfusion-related inclusion criteria and developed postoperative delirium. Controls who did not develop delirium were selected from the same source population of eligible patients and were matched 1:1 based on age (± 5 years), 2- to 2.5-year band of date of surgery, and surgical procedure. For each patient, we calculated the average storage duration of all transfused red cell units. The primary outcome was odds of delirium in patients who were transfused red cell units with exclusive storage duration >14 days compared with that of ≤14 days. Secondary outcomes were odds of delirium with each increasing day of average red cell unit storage duration. We used conditional multivariable regression to test our hypotheses. RESULTS: In conditional multivariable analysis of 87 case-control pairs, there was no difference in the odds of patients developing delirium if they were transfused red cell units with an exclusive storage age >14 days compared with that ≤14 days (odds ratio [OR] 1.83; 95% confidence interval, 0.73-4.58, P = 0.20). Each additional day of average red cell unit storage beyond 14 days was associated with a 1.01- to 1.13-fold increase in the odds of postoperative delirium (OR, 1.07; P = 0.03). Each additional day of average storage beyond 21 days was associated with a 1.02- to 1.23-fold increase in the odds of postoperative delirium (OR, 1.12; P = 0.02). CONCLUSIONS: Transfusion of red cell units that have been stored for >14 days is not associated with increased odds of delirium. However, each additional day of storage >14 or 21 days may be associated with increased odds of postoperative delirium in patients undergoing cardiac surgery. More research is needed to further characterize the association between delirium and storage duration of transfused red cell units.
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Preservação de Sangue/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Delírio/etiologia , Transfusão de Eritrócitos/efeitos adversos , Hemorragia Pós-Operatória/terapia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Baltimore , Bancos de Sangue , Ponte Cardiopulmonar/efeitos adversos , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Ponte de Artéria Coronária/efeitos adversos , Delírio/diagnóstico , Delírio/psicologia , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Hemorragia Pós-Operatória/etiologia , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
Background: Capsule endoscopy (CE) is safe and widely accepted for small bowel (SB) investigation and an alternative to colonoscopy in specific clinical circumstances. As the capsule is orally ingested, the potential risk of aspiration is undoubtedly a constant concern among clinicians. However, it is a rare occurrence and often reported as isolated cases. Therefore, this review systematically compiles all the available data on capsule aspiration in the literature with an aim to provide an update on this complication of CE. Methods: A systematic literature search was performed on PubMed with the search terms 'capsule endoscopy' AND 'aspiration', searched as keywords and MeSH. All observational cohort studies that reported aspiration among complications/outcomes, case reports and series on capsule aspiration were included. Manual citation search was performed. Two extractors reviewed abstract and full-text and performed data extraction. Results: We found 95 relevant articles, and cross-checking references led to the inclusion of an additional 19 articles. We removed 57 and ended with 57 references-with 63 cases of aspirated capsules. One death was reported. The median age was 78, and there was male preponderance. The most common indication for CE was anaemia, and only aspiration of small bowel CE (SBCE) was reported. 61.9% of the aspirations were symptomatic; the most common symptom was coughing. 69.8% of capsules ended in the bronchus, but only 4 cases experienced desaturation. Thirty-two patients needed intervention for retrieval; the aspiration was self-resolved in the remaining. Only four patients had a history of dysphagia. Thirteen instances of aspiration were detected due to real-time viewing, and 24 cases from reviewing the capsule data afterwards. Conclusions: With only 63 cases of aspirated capsules reported in the literature, this event remains rare, is safely managed, and should not discourage patients from the procedure. The importance of careful patient selection is crucial to minimize the likelihood of aspiration and capsule administration should be approached with precautions.
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Wireless capsule endoscopy (CE) has revolutionized gastrointestinal diagnostics, offering a non-invasive means to visualize and monitor the GI tract. This review traces the evolution of CE technology. Addressing the limitations of traditional white light (WL) CE, the paper explores non-WL technologies, integrating diverse sensing modalities and novel biomarkers to enhance diagnostic capabilities. Concluding with an assessment of Technology Readiness Levels, the paper emphasizes the transformative impact of non-WL colon CE devices on GI diagnostics, promising more precise, patient-centric, and accessible healthcare for GI disorders.
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Background and study aims This review aimed to provide an updated and comprehensive review of capsule retention within diverticula, shedding light on the characteristics and management of this rare event in capsule endoscopy. Methods A systematic literature search was conducted across multiple databases. All observational studies that reported capsule retention in a diverticulum among complication and outcomes, as well as case reports and series, were included. Manual cross-checking of references was also performed. Two extractors performed abstract and full-text reviews, as well as data-extraction. Results We found 167 references from Pubmed, Embase, and Web Of Science. Sixty-five duplicates were removed and another 71 references were excluded. Crosschecking of references found additional two articles. In total, 32 articles were included, resulting in a total of 34 cases of retained capsules in diverticula. The median age was 69 and the majority of the patients were male (76.5%). The most common retention occurred in Meckel's diverticulum (32.4%) followed by Zenker's diverticulum (20.6%). Investigation of capsule retention was done with x-ray (50%) and computed tomography (CT) scan (44.1%). Seventeen cases (50%) were asymptomatic. Resolution of the retention happened with endoscopy (35.3%) and surgical management (32.4%), as well as self-resolution (20.6%). Conclusions Due to the small number of cases, diverticula are not a risk factor for incomplete capsule endoscopy examination. It affects mainly elderly, male, asymptomatic patients, and typically is diagnosed with x-rays and CT scans. The most common type is Meckel's diverticulum, and endoscopy is the primary management. Capsule endoscopy retentions are extremely rare, with only 34 cases reported since the technology's introduction.
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The gastrointestinal (GI) tract, particularly the small bowel (SB), can be challenging for novel investigation tools [...].
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Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) is present in 30-60 % of HIV-positive (HIV+) individuals and can be assessed by neuropsychological testing and level of functional impairment. HAND diagnosis therefore requires accurate assessment of functional impairment. The Computer Assessment of Mild Cognitive Impairment (CAMCI) is a computer-based screening tool that includes performance-based measures of functional impairment. We sought to evaluate the CAMCI as a functional assessment tool in HAND. One hundred fourteen HIV+ patients and 38 HIV-negative (HIV-) patients underwent neuropsychological and CAMCI testing. Cognitive status for HIV+ subjects was classified using the Frascati criteria. HIV+ subjects grouped together and classified by cognitive impairment performed worse than HIV- subjects on several of the CAMCI tasks, including following directions to the supermarket (p = 0.05, p = 0.03), recalling which items to purchase (p = 0.01, p = 0.02), and remembering to stop at a supermarket (p < 0.01, p = 0.01) and the post office (p < 0.01, p = 0.03). After controlling for hepatitis C status and depression symptomatology, the tasks "following directions to the supermarket" and the "recalling which items to purchase" were no longer significant. The "remembering to run two separate errands" tasks retained their significance (p < 0.01 for both tasks). A subset of the CAMCI tasks therefore successfully differentiated HIV+ patients from HIV- individuals. Differences in hepatitis C status and depression symptomatology could account for some of the function assessment differences in the CAMCI. These results suggest the CAMCI could be a useful objective performance-based functional assessment in patients with HIV.
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Disfunção Cognitiva/diagnóstico , Depressão/diagnóstico , Diagnóstico por Computador/estatística & dados numéricos , Infecções por HIV/diagnóstico , Hepatite C/diagnóstico , Testes Neuropsicológicos/estatística & dados numéricos , Adulto , Disfunção Cognitiva/complicações , Disfunção Cognitiva/psicologia , Depressão/complicações , Depressão/psicologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/psicologia , Hepatite C/complicações , Hepatite C/psicologia , Humanos , Modelos Logísticos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Análise e Desempenho de TarefasRESUMO
The objective of this study is to compare neuropsychological test performance before and after HIV-1 seroconversion in order to identify possible acute changes in psychomotor speed, memory, attention, and concentration secondary to seroconversion. The study utilized mixed effects models to examine longitudinal neuropsychological test data. We conducted a nested cohort study of 362 male HIV-1 seroconverters enrolled in the Multicenter AIDS Cohort Study. We used linear mixed models with random subject effects to compare repeated neuropsychological test outcomes from 5 years before seroconversion to 2 years after seroconversion on the Trail Making Test (parts A and B), Symbol-Digit Test, Grooved Pegboard (dominant and non-dominant hands), Stroop Color-Interference Test, Rey Auditory Verbal Learning Test, and the CalCAP Reaction Time Test. We found no significant changes in the time-dependent score after seroconversion for the majority of neuropsychological tests used in the Multicenter AIDS Cohort Study. There was a significant change in time trend after seroconversion on part B of the Trail Making Test (p=0.042), but the difference only represented a 2 % decrease in performance. We found the following characteristics to be associated with worse neuropsychological test performance: lower education levels, history of depression, older age, and no previous neurocognitive testing (p< .05). Our results suggest that despite a 50 % decrease in CD4 cell count immediately following infection, HIV-1 does not appear to have a measurable effect on psychomotor or complex cognitive processing for up to 2 years following infection, using this set of neurocognitive measures.
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Infecções por HIV/complicações , Infecções por HIV/psicologia , Soropositividade para HIV/complicações , Soropositividade para HIV/psicologia , Adulto , Estudos de Coortes , HIV-1/imunologia , Humanos , Masculino , Testes NeuropsicológicosRESUMO
BACKGROUND: The Alzheimer's Disease Assessment Scale-Cognitive Behavior section (ADAS-Cog) is the most commonly used cognitive test in AD clinical trials. However, there are concerns about its use in early-stage disease. Herein we examine those concerns using traditional psychometric methods. METHODS: We analyzed ADAS-Cog data (n = 675) based on six psychometric properties: data completeness; scaling assumptions; targeting; reliability; validity; and responsiveness. RESULTS: At the scale-level, criteria tested for data completeness, scaling assumptions (item total correlations 0.33-0.59), targeting (no floor/ceiling effects), reliability (Cronbach's α = 0.74), and validity (correlation with MMSE = -0.70) were satisfied. Responsiveness (baseline to 12 months; n = 145) was moderate to high (effect size = -0.73). However, 8 of 11 ADAS-Cog components had substantial ceiling effects (range 32%-83%), and decreased responsiveness associated with low to moderate effect sizes (0.14-0.65). CONCLUSION: In our study, many patients with AD found large portions of the ADAS-Cog too easy. Future research should consider modifying the ADAS-Cog or developing a new test.
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Doença de Alzheimer/diagnóstico , Testes Neuropsicológicos , Psicometria/métodos , Doença de Alzheimer/psicologia , Humanos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: The Alzheimer's Disease Assessment Scale-Cognitive Behavior section (ADAS-Cog) is the most widely used measure of cognitive performance in AD clinical trials. This key role has rightly brought its performance under increased scrutiny with recent research using traditional psychometric methods, questioning the ADAS-Cog's ability to adequately measure early-stage disease. However, given the limitations of traditional psychometric approaches, herein we use the more sophisticated Rasch Measurement Theory (RMT) methods to fully examine the strengths and weaknesses of the ADAS-Cog, and identify potential paths toward its improvement. METHODS: We analyzed AD Neuroimaging Initiative (ADNI) ADAS-Cog data (675 measurements across four time-points over 2 years) from the AD participants. RMT analysis was undertaken to examine three broad areas: adequacy of scale-to-sample targeting; degree to which, taken together, the ADAS-Cog items adequately perform as a measuring instrument; and how well the scale measured the subjects in the current sample. RESULTS: The 11 ADAS-Cog components mapped-out a measurement continuum, worked together adequately, and were stable across different time-points and samples. However, the scale did not prove to be a good match to the patient sample supporting previous research. RMT analysis also identified problematic "gaps" and "bunching" of the components across the continuum. CONCLUSION: Although the ADAS-Cog has the building blocks of a good measurement instrument, this sophisticated analysis confirms limitations with potentially serious implications for clinical trials. Importantly, and unlike traditional psychometric methods, our RMT analysis has provided important clues aimed at solving the measurement problems of the ADAS-Cog.
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Doença de Alzheimer/diagnóstico , Testes Neuropsicológicos , Psicometria/métodos , Doença de Alzheimer/psicologia , HumanosRESUMO
The Alzheimer's disease (AD) Cognitive Behavior Section (ADAS-Cog) is the most commonly used cognitive test in clinical trials of AD. Recent trials have focused on people earlier in the course of disease; however, there are concerns about using the ADAS-Cog at this crucial stage. Using data from the Alzheimer's disease Neuroimaging Initiative study, we used a range of traditional psychometric tests to evaluate those concerns. This issue of Alzheimer's & Dementia includes two articles that evaluate the ADAS-Cog. These articles report evaluations using two psychometric approaches: traditional methods and new methods. In this review, we provide accompanying background information to this program of research.
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Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Testes Neuropsicológicos , Psicometria/métodos , Ensaios Clínicos como Assunto , Humanos , Projetos de PesquisaRESUMO
INTRODUCTION: The purpose of this study was to characterize brain volumetric differences in HIV seropositive and seronegative men and to determine effects of age, cardiovascular risk, and HIV infection on structural integrity. METHODS: Magnetic resonance imaging was used to acquire high-resolution neuroanatomic data in 160 men aged 50 years and over, including 84 HIV seropositive and 76 seronegative controls. Voxel-based morphometry was used to derive volumetric measurements at the level of the individual voxel. Data from a detailed neuropsychological test battery were recombined into four summary scores representing psychomotor speed, visual memory, verbal memory, and verbal fluency. RESULTS: Both age and HIV status had a significant effect on both gray matter (GM) and white matter (WM) volume. The age-related GM atrophy was primarily in the superior temporal and inferior frontal regions; the HIV-related GM loss included the posterior and inferior temporal lobes, the parietal lobes, and the cerebellum. Among all subjects, the performance on neuropsychological tests, as indexed by a summary variable, was related to the volume of both the GM and WM. Contrary to our predictions, the CVD variables were not linked to brain volume in statistically adjusted models. CONCLUSION: In the post-HAART era, having HIV infection is still linked to atrophy in both GM and WM. Secondly, advancing age, even in this relatively young cohort, is also linked to changes in GM and WM volume. Thirdly, CNS structural integrity is associated with overall cognitive functions, regardless of the HIV infection status of the study volunteers.
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Encéfalo/patologia , Infecções por HIV/patologia , Imageamento por Ressonância Magnética/métodos , Terapia Antirretroviral de Alta Atividade , Atrofia , Doenças Cardiovasculares/diagnóstico por imagem , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Infecções por HIV/tratamento farmacológico , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão , Radiografia , UltrassonografiaRESUMO
Capsule endoscopy (CE) is a valid alternative to conventional gastrointestinal (GI) endoscopy tools. In CE, annotation tools are crucial in developing large and annotated medical image databases for training deep neural networks (DNN). We provide an overview of the described and in-use various annotation systems available, focusing on the annotation of adenomatous polyp pathology in the GI tract. Some studies present promising results regarding time efficiency by implementing automated labelling features in annotation systems. Thus, data are inadequate regarding the general overview for users, and may also be more specific on which features provided are necessary for polyp annotation.
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An association between platelet decline and increased risk of progression to dementia has been observed in an advanced HIV infection cohort study. This investigation evaluated the prognostic significance of platelet decline for dementia, for psychomotor slowing, and for brain injury, as quantified in vivo, in a much larger population of HIV+ men. Platelet counts and neurocognitive data were available from biannual visits of 2,125 HIV+ men participating in the prospective, Multicenter AIDS Cohort Study from 1984 to 2009. Brain volumetric data were also available from an imaging substudy of 83 seropositive participants aged 50 and older. The association of platelet counts with neurocognitive outcome was assessed using Cox proportional hazard models where change in platelet count from baseline was a time-updated variable. Marked platelet decline was associated with increased risk of dementia in univariate analysis (hazard ratio [HR] = 2.5, 95% confidence interval [CI] = 1.8-3.5), but not after adjustment for CD4 cell count, HIV viral load, age, study site, hemoglobin, race, education, smoking, and alcohol use (HR = 1.4, 95% CI = 0.78-2.5). Platelet decline did not predict psychomotor slowing in either univariate (HR = 0.79, 95% CI = 0.58-1.08) or multivariate (HR = 1.10, 95% CI = 0.73-1.67) analysis. Analysis of brain volumetric data, however, indicated a relationship between platelet decline and reduced gray matter volume fraction in univariate (p = 0.06) and multivariate (p < 0.05) analyses. Platelet decline was not an independent predictor of dementia or psychomotor slowing, after adjusting for stage of disease. Findings from a structural brain imaging substudy of older participants, however, support a possible relationship between platelet decline and reduced gray matter.
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Complexo AIDS Demência/patologia , Plaquetas/citologia , Encéfalo/patologia , Complexo AIDS Demência/complicações , Adulto , Contagem de Linfócito CD4 , Progressão da Doença , Seguimentos , HIV/patogenicidade , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neuroimagem , Testes Neuropsicológicos , Contagem de Plaquetas , Prognóstico , Modelos de Riscos Proporcionais , Estudos ProspectivosRESUMO
The objectives of this study are to compare the results of newer performance-based functional assessments in the study of HIV-associated neurocognitive disorders (HAND) and to correlate these functional assessments with specific levels of severity of HAND. One hundred fourteen HIV+ subjects in an existing cohort were evaluated with a medical history, neurological exam, neuropsychological test battery as well as subjective and novel objective measures of functional abilities. Self-reported measures of functional performance included the Karnofsky Performance Scale, a questionnaire for instrumental activities of daily living, and a questionnaire for physical quality of life measures. The newer objective functional performance assessments included the Columbia Medication Management and the San Diego Finances tests. These newer performance-based measures of function were assessed for their ability to predict level of HAND. The two objective measures of functional performance, The Columbia Medication Management Scale and the San Diego Finances Test, were both associated with levels of severity of HAND. The Karnofsky Performance Scale and the questionnaires for role and physical quality of life were subjective measures that were also associated with specific levels of HAND. Newer measures of functional performance can be used to objectively evaluate functional impairment in HAND and validate different levels of HAND.
Assuntos
Complexo AIDS Demência/psicologia , Transtornos Cognitivos/psicologia , Infecções por HIV/psicologia , Aptidão Física/psicologia , Psicometria/métodos , Complexo AIDS Demência/etiologia , Complexo AIDS Demência/fisiopatologia , Atividades Cotidianas/psicologia , Contagem de Linfócito CD4 , Estudos de Casos e Controles , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Feminino , HIV/fisiologia , Infecções por HIV/complicações , Infecções por HIV/fisiopatologia , Humanos , Avaliação de Estado de Karnofsky , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Atividade Motora , Testes Neuropsicológicos , Inquéritos e Questionários , Carga ViralRESUMO
OBJECTIVE: Delirium is common after cardiac surgery, although under-recognized, and its long-term consequences are likely underestimated. The primary goal of this study was to determine whether patients with delirium after coronary artery bypass graft (CABG) surgery have higher long-term out-of-hospital mortality when compared with CABG patients without delirium. METHODS: We studied 5,034 consecutive patients undergoing CABG surgery at a single institution from 1997 to 2007. Presence or absence of neurologic complications, including delirium, was assessed prospectively. Survival analysis was performed to determine the role of delirium in the hazard of death, including a propensity score to adjust for potential confounders. These analyses were repeated to determine the association between postoperative stroke and long-term mortality. RESULTS: Individuals with delirium had an increased hazard of death (adjusted hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.38-1.97) up to 10 years postoperatively, after adjustment for perioperative and vascular risk factors. Patients with postoperative stroke had a HR of 2.34 (95% CI, 1.87-2.92). The effect of delirium on subsequent mortality was the strongest among those without a prior stroke (HR 1.83 vs HR 1.11 [with a prior stroke] [p-interaction = 0.02]) or who were younger (HR 2.42 [<65 years old] vs HR 1.49 [>/=65 years old] [p-interaction = 0.04]). INTERPRETATION: Delirium after cardiac surgery is a strong independent predictor of mortality up to 10 years postoperatively, especially in younger individuals and in those without prior stroke. Future studies are needed to determine the impact of delirium prevention and/or treatment in long-term patient mortality.