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Timothy W. Farrell MD AGSF Leslie Francis PhD JD Teneille Brown JD Lauren E. Ferrante MD MHS Eric Widera MD Ramona Rhodes MD MPH MSCS AGSF Tony Rosen MD MPH Ula Hwang MD MPH Leah J. Witt MD Niranjan Thothala MD MRCP MBA Shan W. Liu MD SD Caroline A. Vitale MD AGSF Ursula K. Braun MD MPH Caroline Stephens PhD RN GNP-BC Debra Saliba MD MPH AGSF 《Journal of the American Geriatrics Society》2020,68(6):1143-1149
Coronavirus disease 2019 (COVID-19) continues to impact older adults disproportionately with respect to serious consequences ranging from severe illness and hospitalization to increased mortality risk. Concurrently, concerns about potential shortages of healthcare professionals and health supplies to address these issues have focused attention on how these resources are ultimately allocated and used. Some strategies, for example, misguidedly use age as an arbitrary criterion that disfavors older adults in resource allocation decisions. This is a companion article to the American Geriatrics Society (AGS) position statement, “Resource Allocation Strategies and Age-Related Considerations in the COVID-19 Era and Beyond.” It is intended to inform stakeholders including hospitals, health systems, and policymakers about ethical considerations that should be considered when developing strategies for allocation of scarce resources during an emergency involving older adults. This review presents the legal and ethical background for the position statement and discusses these issues that informed the development of the AGS positions: (1) age as a determining factor, (2) age as a tiebreaker, (3) criteria with a differential impact on older adults, (4) individual choices and advance directives, (5) racial/ethnic disparities and resource allocation, and (6) scoring systems and their impact on older adults. It also considers the role of advance directives as expressions of individual preferences in pandemics. J Am Geriatr Soc 68:1143–1149, 2020. 相似文献
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Sharmistha Dev MD MPH Andrew A. Gonzalez MD JD MPH Jessica Coffing MPH James E. Slaven MS Shantanu Dev BS Stan Taylor MA Carrie Ballard S. Nicole Hastings MD MHSc Dawn M. Bravata MD 《Academic emergency medicine》2023,30(4):349-358
Objectives
Frailty is a clinical syndrome characterized by decreased physiologic reserve that diminishes the ability to respond to stressors such as acute illness. Veterans Health Administration (VA) emergency departments (ED) are the primary venue of care for Veterans with acute illness and represent key sites for frailty recognition. As questionnaire-based frailty instruments can be cumbersome to implement in the ED, we examined two administratively derived frailty scores for use among VA ED patients.Methods
This national retrospective cohort study included all VA ED visits (2017–2020). We evaluated two administratively derived scores: the Care Assessment Needs (CAN) score and the VA Frailty Index (VA-FI). We categorized all ED visits across four frailty groups and examined associations with outcomes of 30-day and 90-day hospitalization and 30-day, 90-day, and 1-year mortality. We used logistic regression to assess the model performance of the CAN score and the VA-FI.Results
The cohort included 9,213,571 ED visits. With the CAN score, 28.7% of the cohort were classified as severely frail; by VA-FI, 13.2% were severely frail. All outcome rates increased with progressive frailty (p-values for all comparisons < 0.001). For example, for 1-year mortality based on the CAN score frailty was determined as: robust, 1.4%; prefrail, 3.4%; moderately frail, 7.0%; and severely frail, 20.2%. Similarly, for 90-day hospitalization based on VA-FI, frailty was determined as prefrail, 8.3%; mildly frail, 15.3%; moderately frail, 29.5%; and severely frail, 55.4%. The c-statistics for CAN score models were higher than for VA-FI models across all outcomes (e.g., 1-year mortality, 0.721 vs. 0.659).Conclusions
Frailty was common among VA ED patients. Increased frailty, whether measured by CAN score or VA-FI, was strongly associated with hospitalization and mortality and both can be used in the ED to identify Veterans at high risk for adverse outcomes. Having an effective automatic score in VA EDs to identify frail Veterans may allow for better targeting of scarce resources. 相似文献105.
Differential developmental trajectories of magnetic susceptibility in human brain gray and white matter over the lifespan
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Wei Li Bing Wu Anastasia Batrachenko Vivian Bancroft‐Wu Rajendra A. Morey Vandana Shashi Christian Langkammer Michael D. De Bellis Stefan Ropele Allen W. Song Chunlei Liu 《Human brain mapping》2014,35(6):2698-2713
As indicated by several recent studies, magnetic susceptibility of the brain is influenced mainly by myelin in the white matter and by iron deposits in the deep nuclei. Myelination and iron deposition in the brain evolve both spatially and temporally. This evolution reflects an important characteristic of normal brain development and ageing. In this study, we assessed the changes of regional susceptibility in the human brain in vivo by examining the developmental and ageing process from 1 to 83 years of age. The evolution of magnetic susceptibility over this lifespan was found to display differential trajectories between the gray and the white matter. In both cortical and subcortical white matter, an initial decrease followed by a subsequent increase in magnetic susceptibility was observed, which could be fitted by a Poisson curve. In the gray matter, including the cortical gray matter and the iron‐rich deep nuclei, magnetic susceptibility displayed a monotonic increase that can be described by an exponential growth. The rate of change varied according to functional and anatomical regions of the brain. For the brain nuclei, the age‐related changes of susceptibility were in good agreement with the findings from R2* measurement. Our results suggest that magnetic susceptibility may provide valuable information regarding the spatial and temporal patterns of brain myelination and iron deposition during brain maturation and ageing. Hum Brain Mapp 35:2698–2713, 2014. © 2013 Wiley Periodicals, Inc . 相似文献
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Smartt HJ Guilmeau S Nasser SV Nicholas C Bancroft L Simpson SA Yeh N Yang W Mariadason JM Koff A Augenlicht LH 《Gastroenterology》2007,133(1):232-243
BACKGROUND & AIMS: Reduced p27(kip1) expression is a marker of poor prognosis in colorectal neoplasia, and inactivation of p27 in mice (p27(Delta51/Delta51)) causes increased intestinal epithelial cell proliferation and small and large intestinal neoplasia in a diet-dependent manner. Here, we addressed the role of p27 in untransformed intestinal epithelial cells in vivo and the consequence of its targeted inactivation. METHODS: A sequential fractionation procedure was used to isolate murine intestinal epithelial cells relative to their position along the crypt-villus axis, and the levels of cyclins, cyclin-dependent kinases (cdks), and cdk inhibitors and of the complexes formed among them was determined by immunoprecipitation-immunoblotting and kinase assays. RESULTS: As cells exited the proliferative crypt compartment, expression and activity of both cdk2 and cdk4 decreased, in parallel with reduced expression of cyclin A and proliferating cell nuclear antigen (PCNA); expression of cyclin D1, D2, and cyclin E showed little change. As expected, expression of the cdk inhibitors p21, p57, and p16 was highest in differentiated villus cells. Unexpectedly, p27 protein expression was highest in cells of the proliferative crypt compartment where it bound both cdk2 and cdk4. Cdk2 activity was increased in crypt cells from p27(Delta51/Delta51) mice, although cyclin D-associated kinase activity was unchanged (indeed, cyclin D1/2-cdk4 complex levels were reduced). Importantly, cdk2 activity was unchanged in crypt cells from p21(-/-) mice, which do not develop intestinal tumors. CONCLUSIONS: We propose that p27 contributes to intestinal epithelial homeostasis by regulating cdk2 activity in proliferating cells, thus gating cell cycle progression and suppressing intestinal neoplasia. 相似文献
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