14 results match your criteria: "Irvine Clinical Research[Affiliation]"

Cerebral Amyloid Angiopathy, Dementia, and Alzheimer Neuropathologic Changes: Findings From the ACT Autopsy Cohort.

Neurology

November 2024

From the Seattle University (M.-K.S.), Washington; George Washington University (Y.C., A.A., N.M.D., E.Z.), Washington, DC; DC VA Medical Center (A.A.), Washington, DC; University of Alabama at Birmingham (J.M.R.); Irvine Clinical Research (E.Z.), California.

Background And Objectives: Cerebral amyloid angiopathy (CAA) is common in older adults and is associated with dementia. Less is known whether this association is mediated by Alzheimer disease (AD) neuropathologic changes, the examination of which was the objective of this study.

Methods: This was a retrospective cross-sectional examination of the Kaiser Permanente Washington database of the Adult Changes in Thought (ACT) autopsy cohort with information on CAA, dementia, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) (amyloid neuritic plaques), and Braak (tau neurofibrillary tangles).

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Background: Hypertension and physical inactivity are risk factors for stroke. The effect of cardiorespiratory fitness (CRF) on stroke risk in patients with hypertension has not been assessed. We evaluated stroke incidence in patients with hypertension according to CRF and changes in CRF.

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We present a novel explainable artificial intelligence (XAI) method to assess the associations between the temporal patterns in the patient trajectories recorded in longitudinal clinical data and the adverse outcome risks, through explanations for a type of deep neural network model called Hybrid Value-Aware Transformer (HVAT) model. The HVAT models can learn jointly from longitudinal and non-longitudinal clinical data, and in particular can leverage the time-varying numerical values associated with the clinical codes or concepts within the longitudinal data for outcome prediction. The key component of the XAI method is the definitions of two derived variables, the temporal mean and the temporal slope, which are defined for the clinical concepts with associated time-varying numerical values.

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Relationship between Cerebral Microinfarcts and Dementia by Sex: Findings from a community-based Autopsy Study.

Int J Cerebrovasc Dis Stroke

January 2024

Veterans Affairs Medical Center, George Washington University, and School of Medicine, Georgetown University, Washington, DC, USA.

Cerebral microinfarcts are common in older adults and are associated with cognitive impairment. Less is known about sex-related variation in the relationship between cerebral microinfarcts and dementia in older adults, the examination of which was the objective of this study. This case-control study was based on the 727 participants (419 women) in the Adult Changes in Thought (ACT) autopsy data.

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Anti-amyloid therapies (AATs), such as anti-amyloid monoclonal antibodies, are emerging treatments for people with early Alzheimer's disease (AD). AATs target amyloid β plaques in the brain. Amyloid-related imaging abnormalities (ARIA), abnormal signals seen on magnetic resonance imaging (MRI) of the brain in patients with AD, may occur spontaneously but occur more frequently as side effects of AATs.

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Mid-life high blood pressure (BP) is a risk factor for cerebral microinfarcts. Less is known about the relationship between late-life BP and cerebral microinfarcts, the examination of which is the objective of the current study. This case-control study analyzed data from 551 participants (94.

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Hybrid Value-Aware Transformer Architecture for Joint Learning from Longitudinal and Non-Longitudinal Clinical Data.

J Pers Med

June 2023

Department of Clinical Research and Leadership, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA.

Transformer is the latest deep neural network (DNN) architecture for sequence data learning, which has revolutionized the field of natural language processing. This success has motivated researchers to explore its application in the healthcare domain. Despite the similarities between longitudinal clinical data and natural language data, clinical data presents unique complexities that make adapting Transformer to this domain challenging.

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Cerebral microinfarcts are associated with cognitive impairment and dementia. Small vessel diseases such as cerebral arteriolosclerosis and cerebral amyloid angiography (CAA) have been found to be associated with microinfarcts. Less is known about the associations of these vasculopathies with the presence, numbers, and location of microinfarcts.

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Alzheimer's disease (AD) is characterized by cognitive impairment in the presence of cerebral amyloid plaques and neurofibrillary tangles. Less is known about the characteristics and predictors of resilience to cognitive impairment in the presence of neuropathological evidence of AD, the focus of this study. Of 3170 adults age ≥65 years in the National Alzheimer's Coordinating Center (NACC) brain autopsy cohort, 1373 had evidence of CERAD level moderate to frequent neuritic plaque density and Braak stage V-VI neurofibrillary tangles.

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Transformer is the latest deep neural network (DNN) architecture for sequence data learning that has revolutionized the field of natural language processing. This success has motivated researchers to explore its application in the healthcare domain. Despite the similarities between longitudinal clinical data and natural language data, clinical data presents unique complexities that make adapting Transformer to this domain challenging.

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Article Synopsis
  • Cardiorespiratory fitness (CRF) is linked to better overall health and longevity, but its connection to Alzheimer's disease and related dementias (ADRD) is less understood.
  • A study involving over 649,000 US veterans analyzed the relationship between CRF levels and the incidence of ADRD over an average follow-up period of about 8 years.
  • Results showed that higher CRF levels were associated with a lower risk of developing ADRD, suggesting that improving fitness might help reduce ADRD risk in the future.
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Enhancing Clinical Data Analysis by Explaining Interaction Effects between Covariates in Deep Neural Network Models.

J Pers Med

January 2023

Department of Clinical Research and Leadership, School of Medicine and Health Sciences, George Washington University, Washington, DC 20037, USA.

Deep neural network (DNN) is a powerful technology that is being utilized by a growing number and range of research projects, including disease risk prediction models. One of the key strengths of DNN is its ability to model non-linear relationships, which include covariate interactions. We developed a novel method called interaction scores for measuring the covariate interactions captured by DNN models.

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The high cost and time for developing a new drug or repositioning a partially-developed drug has fueled interest in "repurposing" drugs. Drug repurposing is particularly of interest for Alzheimer's disease (AD) or AD-related dementias (ADRD) because there are no unrestricted disease-modifying treatments for ADRD. We have designed and pilot tested a 3-Step Medication-Wide Association Study Plus (MWAS+) approach to rigorously accelerate the identification of drugs with a high potential to be repurposed for delaying and preventing AD/ADRD: Step 1 is a hypothesis-free exploration; Step 2 is mechanistic filtering; And Step 3 is hypothesis testing using observational data and prospective cohort design.

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Background: To evaluate the glycemic control, lipid effects, and safety of pioglitazone in patients with type 2 diabetes mellitus.

Design And Methods: Patients (n = 197) with type 2 diabetes mellitus, a hemoglobin A1c (HbA1c) > or = 8.0%, fasting plasma glucose (FPG) > 7.

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