Publications by authors named "Samantha Walters"

Subjective cognitive concerns (SCC) are common even in cognitively normal older adults who lack objectively-detectable deficits on standard neuropsychological evaluation. The clinical relevance of these concerns, particularly considering the nature of concerns (e.g.

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Background: Palliative treatment has been associated with improved quality of life and survival for a wide variety of metastatic cancers. However, it is unclear whether the benefits of palliative treatment are uniformly experienced across the US cancer population. We evaluated patterns and outcomes of palliative treatment based on socioeconomic, sociodemographic and treating facility characteristics.

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Importance: Insurance status has been linked to important differences in cancer treatment and outcomes in the US. With more than 15 million individuals gaining health insurance through Medicaid expansion, there is an increasing need to understand the implications of this policy within the US cancer population. This review provides an overview of the fundamental principles and nuances of Medicaid expansion, as well as the implications for cancer care.

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Introduction: There are currently two recommended radiation strategies for clinical stage III NSCLC: a lower "preoperative" (45-54 Gy) and a higher "definitive/nonsurgical" (60-70 Gy) dose. We sought to determine if definitive radiation doses should be used in the preoperative setting given that many clinical stage III patients planned for surgery are ultimately managed with chemoradiation alone.

Methods: Using the National Cancer Database data from 2006 to 2016, we performed a comparative effectiveness analysis of stage III N2 patients who received chemoradiotherapy.

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Introduction: Patients with early-stage NSCLC typically must choose between a surgery with superior local control (lobectomy) or one that preserves lung parenchyma (wedge). Recognizing that many patients with cancer have competing mortality risks unrelated to cancer, we investigated whether an established model of predicting life expectancy could be used to identify patients with stage I NSCLC for whom survival after wedge is not different from lobectomy.

Methods: A retrospective cohort study using the National Cancer Institute's Surveillance Epidemiology and End Results-Medicare was performed to evaluate survival among treatment-naive patients, diagnosed 2005-2015, who underwent lobectomy or wedge for stage I (≤2 cm tumors) NSCLC.

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Introduction: Apolipoprotein E () ε4, the strongest non-Mendelian genetic risk factor for Alzheimer's disease (AD), has been shown to affect brain capillaries in mice, with potential implications for AD-related neurodegenerative disease. However, human brain capillaries cannot be directly visualized in vivo. We therefore used retinal imaging to test ε4 effects on human central nervous system capillaries.

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Progressive word-finding difficulty is a primary cognitive complaint among healthy older adults and a symptom of pathological aging. Classic measures of visual confrontation naming, however, show ceiling effects among healthy older adults. To address the need for a naming test that is sensitive to subtle, age-related word-finding decline, we developed the Rapid Naming Test (RNT), a computerized, one-minute, speeded visual naming test.

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Background: Complete tumor removal via esophagectomy or endoscopic excision has been associated with the greatest survival in early-stage esophageal cancer. However, patient health, anatomy, or goals of care may render patients ineligible for excision or resection. In this setting, chemoradiation (CRT) may be considered as a nonsurgical approach, however the outcomes associated with CRT in early-stage esophageal cancer are incompletely understood.

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Background: Atypical pulmonary carcinoid tumors represent a subset of non-small cell lung cancer; however, their relative infrequency has left prognosis, management and long-term survival associated with atypical carcinoids, incompletely characterized.

Methods: Patients aged 18 years or more diagnosed with atypical or typical pulmonary carcinoid between 2010 and 2015 within the National Cancer Database were evaluated. Survival was measured using Kaplan-Meier survival and multivariable Cox proportional hazards regression, adjusting for patient and tumor attributes.

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Objective: The outcomes of patients treated on the COVID-minimal pathway were evaluated during a period of surging COVID-19 hospital admissions, to determine the safety of continuing to perform urgent operations during the pandemic.

Summary Of Background Data: Crucial treatments were delayed for many patients during the COVID-19 pandemic, over concerns for hospital-acquired COVID-19 infections. To protect cancer patients whose survival depended on timely surgery, a "COVID-minimal pathway" was created.

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Method: Clinically normal older adults (52-92 years old) were followed longitudinally for up to 8 years after completing a memory paradigm at baseline [Story Recall Test (SRT)] that assessed delayed recall at 30 min and 1 week. Subsets of the cohort underwent neuroimaging (N = 134, mean age = 75) and neuropsychological testing (N = 178-207, mean ages = 74-76) at annual study visits occurring approximately 15-18 months apart. Mixed-effects regression models evaluated if baseline SRT performance predicted longitudinal changes in gray matter volumes and cognitive composite scores, controlling for demographics.

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We aimed to test the hypothesis that elevated neocortical β-amyloid (Aβ), a hallmark feature of Alzheimer's disease (AD), predicts sex-specific cognitive trajectories in clinically normal older adults, with women showing greater risk of decline than men. Florbetapir Aβ positron emission tomography (PET) was acquired in 149 clinically normal older adults (52% female, = 74). Participants underwent cognitive testing at baseline and during annual follow-up visits over a timespan of up to 5.

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This cohort study evaluates different approaches for estimating the population of individuals eligible for Medicaid expansion under the Affordable Care Act in the context of researching changes in cancer care after Medicaid expansion.

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Objective: Despite the losses commonly associated with aging, older adults seem to possess particularly preserved emotional regulation. To further understand this phenomenon, the authors examined longitudinal trajectories between age, depressive symptoms, brain structure, and cognition.

Methods: Seven hundred and sixteen functionally intact older adults (age M = 67.

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: Physical activity closely relates to cognition and brain structure as we age. However, the neural mechanisms underlying this relationship in humans remain less clear. Functional connectivity (FC), measured by task-free functional MRI (tf-fMRI) is a dynamic marker of network activity and may be a sensitive indicator of the brain's response to exercise over time.

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Background: Active lifestyles are related to better cognitive aging outcomes, yet the unique role of different types of activity are unknown.

Objective: To examine the independent contributions of physical (PA) versus cognitive (CA) leisure activities to brain and cognitive aging.

Methods: Independent samples of non-demented older adults from University of California, San Francisco Hillblom Aging Network (UCSF; n = 344 typically aging) and University of California, Davis Diversity cohort (UCD; n = 485 normal to MCI) completed: 1) self-reported engagement in current PA and CA (UCSF: Physical Activity Scale for the Elderly and Cognitive Activity Scale; UCD: Life Experiences Assessment Form); 2) neuropsychological batteries; and 3) neuroimaging total gray matter volume, white matter hyperintensities, and/or global fractional anisotropy.

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Chronic systemic sterile inflammation is implicated in the pathogenesis of cerebrovascular disease and white matter injury. Non-invasive blood markers for risk stratification and dissection of inflammatory molecular substrates in vivo are lacking. We sought to identify whether an interconnected network of inflammatory biomarkers centered on IL-18 and all previously associated with white matter lesions could detect overt and antecedent white matter changes in two populations at risk for cerebral small vessel disease.

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Introduction: We investigated plasma proteomic markers of astrocytopathy, brain degeneration, plasticity, and inflammation in sporadic early-onset versus late-onset Alzheimer's disease (EOAD and LOAD).

Methods: Plasma was analyzed using ultra-sensitive immuno-based assays from 33 EOAD, 30 LOAD, and 36 functionally normal older adults.

Results: Principle component analyses identified 3 factors: trophic (BDNF, VEGF, TGFβ), degenerative (GFAP, NfL), and inflammatory (TNFα, IL-6, IP-10, IL-10).

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Background: Central nervous system levels of tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine, regulate the neuroinflammatory response and may play a role in age-related neurodegenerative diseases. The longitudinal relation between peripheral levels of TNF-α and typical brain aging is understudied. We hypothesized that within-person increases in systemic TNF-α would track with poorer brain health outcomes in functionally normal adults.

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Cerebral perfusion declines across the lifespan and is altered in the early stages of several age-related neuropathologies. Little is known, however, about the longitudinal evolution of perfusion in healthy older adults, particularly when perfusion is quantified using magnetic resonance imaging with arterial spin labeling (ASL). The objective was to characterize longitudinal perfusion in typically aging adults and elucidate associations with cognition and brain structure.

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Age-related cognitive decline is a public health problem but highly diverse and difficult to predict. We captured nonoverlapping cognitive phenotypes in high-functioning adults and identified baseline factors differentiating trajectories. Three hundred fourteen functionally normal adults (M = 69 y) completed 2+ visits.

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Frontotemporal dementia refers to a group of progressive neurodegenerative syndromes usually caused by the accumulation of pathological tau or TDP-43 proteins. The effects of these proteins in the brain are complex, and each can present with several different clinical syndromes. Clinical efficacy trials of drugs targeting these proteins must use endpoints that are meaningful to all participants despite the variability in symptoms across patients.

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Although leukocyte telomere length (TL) shortens over the lifespan and is associated with diseases of aging, little is known about the relationships between TL, memory, and brain structure. Sixty-nine functionally normal older adults (mean age = 71.7) were assessed at 2 time points (mean interval = 2.

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Objective: The aim oft his study was to compare the effects of 10 common exercises to traditional pelvic floor muscle (PFM) contractions (Kegel) on levator hiatus (LH) area and PFM length and strength.

Methods: This is a cross-sectional study of 15 healthy postpartum women. Ten exercises were studied.

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The default mode network (DMN) supports memory functioning and may be sensitive to preclinical Alzheimer's pathology. Little is known, however, about the longitudinal trajectory of this network's intrinsic functional connectivity (FC). In this study, we evaluated longitudinal FC in 111 cognitively normal older human adults (ages 49-87, 46 women/65 men), 92 of whom had at least three task-free fMRI scans ( = 353 total scans).

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