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Jeremy D. Walston

Bio: Jeremy D. Walston is an academic researcher from Johns Hopkins University. The author has contributed to research in topics: Population & Medicine. The author has an hindex of 80, co-authored 302 publications receiving 39548 citations. Previous affiliations of Jeremy D. Walston include Johns Hopkins University School of Medicine & University of Baltimore.


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Journal ArticleDOI
TL;DR: This study provides a potential standardized definition for frailty in community-dwelling older adults and offers concurrent and predictive validity for the definition, and finds that there is an intermediate stage identifying those at high risk of frailty.
Abstract: Background: Frailty is considered highly prevalent in old age and to confer high risk for falls, disability, hospitalization, and mortality. Frailty has been considered synonymous with disability, comorbidity, and other characteristics, but it is recognized that it may have a biologic basis and be a distinct clinical syndrome. A standardized definition has not yet been established. Methods: To develop and operationalize a phenotype of frailty in older adults and assess concurrent and predictive validity, the study used data from the Cardiovascular Health Study. Participants were 5,317 men and women 65 years and older (4,735 from an original cohort recruited in 1989-90 and 582 from an African American cohort recruited in 1992-93). Both cohorts received almost identical baseline evaluations and 7 and 4 years of follow-up, respectively, with annual examinations and surveillance for outcomes including incident disease, hospitalization, falls, disability, and mortality. Results: Frailty was defined as a clinical syndrome in which three or more of the following criteria were present: unintentional weight loss (10 lbs in past year), self-reported exhaustion, weakness (grip strength), slow walking speed, and low physical activity. The overall prevalence of frailty in this community-dwelling population was 6.9%; it increased with age and was greater in women than men. Four-year incidence was 7.2%. Frailty was associated with being African American, having lower education and income, poorer health, and having higher rates of comorbid chronic diseases and disability. There was overlap, but not concordance, in the cooccurrence of frailty, comorbidity, and disability. This frailty phenotype was independently predictive (over 3 years) of incident falls, worsening mobility or ADL disability, hospitalization, and death, with hazard ratios ranging from 1.82 to 4.46, unadjusted, and 1.29-2.24, adjusted for a number of health, disease, and social characteristics predictive of 5-year mortality. Intermediate frailty status, as indicated by the presence of one or two criteria, showed intermediate risk of these outcomes as well as increased risk of becoming frail over 3-4 years of follow-up (odds ratios for incident frailty = 4.51 unadjusted and 2.63 adjusted for covariates, compared to those with no frailty criteria at baseline). Conclusions: This study provides a potential standardized definition for frailty in community-dwelling older adults and offers concurrent and predictive validity for the definition. It also finds that there is an intermediate stage identifying those at high risk of frailty. Finally, it provides evidence that frailty is not synonymous with either comorbidity or disability, but comorbidity is an etiologic risk factor for, and disability is an outcome of, frailty. This provides a potential basis for clinical assessment for those who are frail or at risk, and for future research to develop interventions for frailty based on a standardized ascertainment of frailty.

16,255 citations

Journal ArticleDOI
TL;DR: The results of the 2004 American Geriatrics Society/National Institute on Aging conference on a Research Agenda on Frailty in Older Adults, which brought together a diverse group of clinical and basic scientists to encourage further investigation in this area are reported on.
Abstract: Evolving definitions of frailty, and improved understanding of molecular and physiological declines in multiple systems that may increase vulnerability in frail, older adults has encouraged investigators from many disciplines to contribute to this emerging field of research. This article reports on the results of the 2004 American Geriatrics Society/National Institute on Aging conference on a Research Agenda on Frailty in Older Adults, which brought together a diverse group of clinical and basic scientists to encourage further investigation in this area. This conference was primarily focused on physical and physiological aspects of frailty. Although social and psychological aspects of frailty are critically important and merit future research, these topics were largely beyond the scope of this meeting. Included in this article are sections on the evolving conceptualization and definitions of frailty; physiological underpinnings of frailty, including the potential contributions of inflammatory, endocrine, skeletal muscle, and neurologic system changes; potential molecular and genetic contributors; proposed animal models; and integrative, system biology approaches that may help to facilitate future frailty research. In addition, several specific recommendations as to future directions were developed from suggestions put forth by participants, including recommendations on definition and phenotype development, methodological development to perform clinical studies of individual-system and multiple-system vulnerability to stressors, development of animal and cellular models, application of population-based studies to frailty research, and the development of large collaborative networks in which populations and resources can be shared. This meeting and subsequent article were not meant to be a comprehensive review of frailty research; instead, they were and are meant to provide a more-targeted research agenda-setting process.

1,372 citations

Journal ArticleDOI
TL;DR: The frailty definition developed in the CHS is applicable across diverse population samples and identifies a profile of high risk of multiple adverse outcomes and is consistent with the widely held theory that conceptualizes frailty as a syndrome.
Abstract: Background "Frailty" is an adverse, primarily gerontologic, health condition regarded as frequent with aging and having severe consequences. Although clinicians claim that the extremes of frailty can be easily recognized, a standardized definition of frailty has proved elusive until recently. This article evaluates the cross-validity, criterion validity, and internal validity in the Women's Health and Aging Studies (WHAS) of a discrete measure of frailty recently validated in the Cardiovascular Health Study (CHS). Methods The frailty measure developed in CHS was delineated in the WHAS data sets. Using latent class analysis, we evaluated whether criteria composing the measure aggregate into a syndrome. We verified the criterion validity of the measure by testing whether participants defined as frail were more likely than others to develop adverse geriatric outcomes or to die. Results The distributions of frailty in the WHAS and CHS were comparable. In latent class analyses, the measures demonstrated strong internal validity vis a vis stated theory characterizing frailty as a medical syndrome. In proportional hazards models, frail women had a higher risk of developing activities of daily living (ADL) and/or instrumental ADL disability, institutionalization, and death, independently of multiple potentially confounding factors. Conclusions The findings of this study are consistent with the widely held theory that conceptualizes frailty as a syndrome. The frailty definition developed in the CHS is applicable across diverse population samples and identifies a profile of high risk of multiple adverse outcomes.

1,077 citations

Journal ArticleDOI
TL;DR: The Interventions on Frailty Working Group developed recommendations to screen, recruit, evaluate, and retain frail older persons in clinical trials.
Abstract: The discovery of effective interventions to prevent or delay disability in older persons is a public health priority. Most likely to benefit from such interventions are frail individuals who are not yet disabled and those with early disability who are at high risk of progression. In spite of this frail older persons have often been excluded from research on the assumption that they would not tolerate testing or benefit from treatment. The Interventions on Frailty Working Group developed recommendations to screen, recruit, evaluate, and retain frail older persons in clinical trials. Specific recommendations are: Eligibility screening should include a multistage process, to quickly exclude those who are too well and those who are too sick. Inclusion criteria should target those most likely to benefit, be meaningful to clinicians, and reflect advancements in the frailty research area. Disability outcome measures should include self-reported, objective, and proxy measures. Strategies to improve retention and compliance and to monitor their effectiveness should be an integral part of the study design. Estimation of cost and sample size should contemplate high dropout rates and interference by competing outcomes. Additional research is needed to refine criteria for screening frail older persons, identify objective measures of disability that are reliable and valid in frail older persons, and improve the informed consent process for high-risk participants, recognizing that research in this subgroup is essential to improving their health outcomes.

955 citations


Cited by
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Journal ArticleDOI
TL;DR: This study provides a potential standardized definition for frailty in community-dwelling older adults and offers concurrent and predictive validity for the definition, and finds that there is an intermediate stage identifying those at high risk of frailty.
Abstract: Background: Frailty is considered highly prevalent in old age and to confer high risk for falls, disability, hospitalization, and mortality. Frailty has been considered synonymous with disability, comorbidity, and other characteristics, but it is recognized that it may have a biologic basis and be a distinct clinical syndrome. A standardized definition has not yet been established. Methods: To develop and operationalize a phenotype of frailty in older adults and assess concurrent and predictive validity, the study used data from the Cardiovascular Health Study. Participants were 5,317 men and women 65 years and older (4,735 from an original cohort recruited in 1989-90 and 582 from an African American cohort recruited in 1992-93). Both cohorts received almost identical baseline evaluations and 7 and 4 years of follow-up, respectively, with annual examinations and surveillance for outcomes including incident disease, hospitalization, falls, disability, and mortality. Results: Frailty was defined as a clinical syndrome in which three or more of the following criteria were present: unintentional weight loss (10 lbs in past year), self-reported exhaustion, weakness (grip strength), slow walking speed, and low physical activity. The overall prevalence of frailty in this community-dwelling population was 6.9%; it increased with age and was greater in women than men. Four-year incidence was 7.2%. Frailty was associated with being African American, having lower education and income, poorer health, and having higher rates of comorbid chronic diseases and disability. There was overlap, but not concordance, in the cooccurrence of frailty, comorbidity, and disability. This frailty phenotype was independently predictive (over 3 years) of incident falls, worsening mobility or ADL disability, hospitalization, and death, with hazard ratios ranging from 1.82 to 4.46, unadjusted, and 1.29-2.24, adjusted for a number of health, disease, and social characteristics predictive of 5-year mortality. Intermediate frailty status, as indicated by the presence of one or two criteria, showed intermediate risk of these outcomes as well as increased risk of becoming frail over 3-4 years of follow-up (odds ratios for incident frailty = 4.51 unadjusted and 2.63 adjusted for covariates, compared to those with no frailty criteria at baseline). Conclusions: This study provides a potential standardized definition for frailty in community-dwelling older adults and offers concurrent and predictive validity for the definition. It also finds that there is an intermediate stage identifying those at high risk of frailty. Finally, it provides evidence that frailty is not synonymous with either comorbidity or disability, but comorbidity is an etiologic risk factor for, and disability is an outcome of, frailty. This provides a potential basis for clinical assessment for those who are frail or at risk, and for future research to develop interventions for frailty based on a standardized ascertainment of frailty.

16,255 citations

Journal ArticleDOI
TL;DR: Authors/Task Force Members: Piotr Ponikowski* (Chairperson) (Poland), Adriaan A. Voors* (Co-Chair person) (The Netherlands), Stefan D. Anker (Germany), Héctor Bueno (Spain), John G. F. Cleland (UK), Andrew J. S. Coats (UK)

13,400 citations

Journal ArticleDOI
TL;DR: Mice adds new functionality for imputing multilevel data, automatic predictor selection, data handling, post-processing imputed values, specialized pooling routines, model selection tools, and diagnostic graphs.
Abstract: The R package mice imputes incomplete multivariate data by chained equations. The software mice 1.0 appeared in the year 2000 as an S-PLUS library, and in 2001 as an R package. mice 1.0 introduced predictor selection, passive imputation and automatic pooling. This article documents mice, which extends the functionality of mice 1.0 in several ways. In mice, the analysis of imputed data is made completely general, whereas the range of models under which pooling works is substantially extended. mice adds new functionality for imputing multilevel data, automatic predictor selection, data handling, post-processing imputed values, specialized pooling routines, model selection tools, and diagnostic graphs. Imputation of categorical data is improved in order to bypass problems caused by perfect prediction. Special attention is paid to transformations, sum scores, indices and interactions using passive imputation, and to the proper setup of the predictor matrix. mice can be downloaded from the Comprehensive R Archive Network. This article provides a hands-on, stepwise approach to solve applied incomplete data problems.

10,234 citations

Journal ArticleDOI
TL;DR: The European Working Group on Sarcopenia in Older People (EWGSOP) developed a practical clinical definition and consensus diagnostic criteria for age-related sarcopenia as discussed by the authors.
Abstract: The European Working Group on Sarcopenia in Older People (EWGSOP) developed a practical clinical definition and consensus diagnostic criteria for age-related sarcopenia. EWGSOP included representatives from four participant organisations, i.e. the European Geriatric Medicine Society, the European Society for Clinical Nutrition and Metabolism, the International Association of Gerontology and Geriatrics-European Region and the International Association of Nutrition and Aging. These organisations endorsed the findings in the final document. The group met and addressed the following questions, using the medical literature to build evidence-based answers: (i) What is sarcopenia? (ii) What parameters define sarcopenia? (iii) What variables reflect these parameters, and what measurement tools and cut-off points can be used? (iv) How does sarcopenia relate to cachexia, frailty and sarcopenic obesity? For the diagnosis of sarcopenia, EWGSOP recommends using the presence of both low muscle mass + low muscle function (strength or performance). EWGSOP variously applies these characteristics to further define conceptual stages as 'presarcopenia', 'sarcopenia' and 'severe sarcopenia'. EWGSOP reviewed a wide range of tools that can be used to measure the specific variables of muscle mass, muscle strength and physical performance. Our paper summarises currently available data defining sarcopenia cut-off points by age and gender; suggests an algorithm for sarcopenia case finding in older individuals based on measurements of gait speed, grip strength and muscle mass; and presents a list of suggested primary and secondary outcome domains for research. Once an operational definition of sarcopenia is adopted and included in the mainstream of comprehensive geriatric assessment, the next steps are to define the natural course of sarcopenia and to develop and define effective treatment.

8,440 citations