Stephanie A Studenski's research while affiliated with University of Pittsburgh and other places

Publications (237)

Article
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Objective: To develop and validate a high-risk predictive model that identifies, at least, one common adverse event in older population: early readmission (up to 30 days after discharge), long hospital stays (10 days or more) or in-hospital deaths. Methods: This was a retrospective cohort study including patients aged 60 years or older (n=340) a...
Article
Importance: Observational evidence suggests that higher physical activity is associated with slower kidney function decline; however, to our knowledge, no large trial has evaluated whether activity and exercise can ameliorate kidney function decline in older adults. Objective: To evaluate whether a moderate-intensity exercise intervention can af...
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Importance Among older people, slow walking is an early indicator of risk for Alzheimer disease (AD). However, studies that have assessed this association have not considered that slow walking may have different causes, some of which are not necessarily associated with higher AD risk. Objective To evaluate whether low activity fragmentation among...
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Aging is associated with distinct phenotypical, physiological, and functional changes, leading to disease and death. The progression of aging-related traits varies widely among individuals, influenced by their environment, lifestyle, and genetics. In this study, we conducted physiologic and functional tests cross-sectionally throughout the entire l...
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Background and objectives: Lawton's Ecological Model of Aging suggests that associations between environment and mobility differ based on individual factors such as cognitive decline. Research design and methods: Virtual walkability audits were conducted within 1/8 mile of residences of older adults (n=545; average age=82; 57% female; 33% Black)...
Article
We previously showed that dual decline in memory and gait speed was associated with an increased risk of dementia compared to memory or gait decline only or no decline. We now characterized cognitive and neuroimaging profiles of dual decliners by comparing longitudinal rates of change in various cognitive domains (n = 664) and brain volumes (n = 39...
Article
Impaired mobility occurs in up to half of community-dwelling older adults and is associated with poor health outcomes and high health care costs. Although the built environment impacts mobility, most studies of older adults lack information about environmental-level factors. In-person observational audits can be utilized but cannot assess the histo...
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Background: Muscle strength and brain volume decline with aging; changes in the brain manifested as change in volume may play a role in age-related strength loss, but this hypothesis has never been tested longitudinally. We examined longitudinal associations between brain volume changes and knee extension peak torque change in participants of the...
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Background Walking speed during fast-paced walking task has been associated with cognitive function. It is unclear what underlying brain structures are related to fast-paced walking. We investigated the association of gray matter density with fast-paced walking speed and usual-paced walking speed. Methods We collected data from 284 older adults fr...
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Importance Dual decline in both memory and gait speed may characterize a group of older individuals at high risk for future dementia. Objective To assess the risk of dementia in older persons who experience parallel declines in memory and gait speed compared with those who experience no decline or decline in either memory or gait speed only. Desi...
Chapter
Reduced mobility is a powerful predictor of health outcomes and mortality; however, mobility assessment is often neglected in nonspecialized clinical settings. Cognitive function plays a key role in reduced mobility. Both cognition and mobility predict future fall risk. This chapter summarizes findings on dismobility in aging and its role as a pred...
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Background: Socioeconomics may explain black-white differences in physical performance; few studies examine racial differences among socioeconomically similar groups. Performance is also affected by body composition and specific strength, which differ by race. We assessed whether racial differences in physical performance exist among older adults...
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Objectives: Given the need to detect subclinical changes in brain health that sometimes occur with aging in apparently healthy older adults, we assessed whether bimanual gesture imitation performance, simple to assess clinically, can detect age effects and alterations in cognition, olfaction, and movement. Design: Cross-sectional study. Setting...
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Background: Slow gait speed is a powerful predictor of disability in activities of daily living and mortality. Muscle strength and body composition change over time, but their changes differ by sex. How these parameters jointly affect gait speed decline is unknown. Understanding this association could help develop and evaluate the sex-specific eff...
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Background/objectives: To assess whether gait speed under complex conditions predicts long-term risk for mobility disability as well as or better than usual-pace gait speed. Design: Longitudinal cohort study. Setting/participants: Subsample of Health Aging and Body Composition study with follow-up from 2002 to 2003 to 2010 to 2011, including 3...
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Objectives: To determine whether the trajectory of preclinical lap time variability from a 400-m walk differentiates participants with future mild cognitive impairment (MCI)/Alzheimer's disease (AD) from matched controls. Design: A case-control retrospective study embedded in a large longitudinal cohort study, the Baltimore Longitudinal Study of...
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Background The parallel decline of mobility and cognition with aging is explained in part by shared brain structural changes that are related to fitness. However, the temporal sequence between fitness, brain structural changes, and mobility loss has not been fully evaluated. Methods Participants were from the Baltimore Longitudinal Study of Aging,...
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The American Geriatrics Society convened a conference in Bethesda, Maryland, to explore models and studies of aging. This was the second of three conferences, supported by a U13 grant from the National Institute on Aging, to aid recipients of Grants for Early Medical/Surgical Specialists Transition to Aging Research (GEMSSTAR) in integrating geriat...
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In the last two decades, great strides were made in our ability to extend the lifespan of model organisms through dietary and other manipulations. Survival curves provide evidence of altered aging processes but are uninformative on what lead to that increase in lifespan. Longitudinal assessments of health and function during intervention studies co...
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Background Idiopathic Parkinson’s disease (IPD) has a long preclinical phase. Research question This study assesses data on prediagnostic markers of IPD from a longitudinal, natural history study of aging. Methods Participants were selected from the database of the Baltimore Longitudinal Study of Aging, and included 10 prediagnosed IPD cases (eig...
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Black older adults have poorer health outcomes and physical performance than White older adults, and recent studies have indicated that these disparities may begin in midlife. In many studies, racial disparities are explained by socioeconomic status. In the Baltimore Longitudinal Study of Aging, Black participants have approximately an equal income...
Article
Older age and cerebral small vessel disease (cSVD) predict slower gait. However, some adults maintain faster gait speed despite older age and/or the presence of cSVD. We hypothesize that higher levels of nigrostriatal dopamine can help offset the detrimental effects of older age and cSVD on gait speed. Cross-sectional data are from 85 adults aged 2...
Article
OBJECTIVES To evaluate the Pittsburgh Fatigability Scale (PFS) as a predictor of performance and functional decline in mobility‐intact older adults. DESIGN Longitudinal analysis of Baltimore Longitudinal Study of Aging data. SETTING National Institute on Aging, Clinical Research Unit, Baltimore, Maryland. PARTICIPANTS Mobility‐intact men (46.8%)...
Article
Purpose: Acceleration capacity affects physical function, but whether it differentially affects men versus women or weak versus strong individuals is less known. We investigated whether knee extension rate of velocity development (RVD, a measure of acceleration) is associated with walking performance independent of peak torque and whether the rela...
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Background: With aging, the ability to generate muscle force decreases, contributing to declines in physical functions such as walking. While most studies assess muscle force by peak torque, the rate of torque development (RTD) reflects a dynamic component of muscle performance that is important for physical function. Using data from the Baltimore...
Data
Fig. S2. Relationship between age and peak torque in isometric knee extension at 120 deg. In men, the solid line is a piecewise regression with a breakpoint estimated at 63.0 [51.2‐74.8] years old. In women, the solid line is a piecewise regression with a breakpoint estimated at 61.9 [55.0‐67.7] years old. Fig. S3. The relationship between age and...
Data
Table S4a. Relationship of rate of torque development or isometric knee extension peak torque with physical function tests in men over 60 years old Table S4b. Relationships of rate of torque development or isometric knee extension peak torque with physical function tests in women over 60 years old Table S5a. Relationships of rate of torque develo...
Article
Background In older persons, lower hand grip strength is associated with poorer cognition. Little is known about how the rate of muscle contraction relates to cognition and upper extremity motor function, and sex differences are understudied. Methods Linear regression, adjusting for age, race, education, body mass index, appendicular lean mass, an...
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Traditional clinical care models focus on the measurement and normalization of individual organ systems and de-emphasize aspects of health related to the integration of physiologic systems. Measures of physical, cognitive and sensory, and psychosocial or emotional function predict important health outcomes like death and disability independently fr...
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Background Physical activity (PA) prevents disease and promotes longevity, yet few older adults meet the recommended daily guidelines. Wearable PA and heart rate monitors provide the opportunity to define age-related differences in the absolute and relative intensity of daily activities, and provide insight into the underlying factors influencing P...
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Objectives To determine whether intervention‐induced physical activity (PA) changes in sedentary older adults differed according to dopamine‐related genotype. Design Randomized clinical trial (Lifestyle Interventions and Independence for Elders Trial (2010–13)). Setting Multicenter study, 8 U.S. locations. Participants Volunteer sample of sedent...
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Objectives: To examine the potential contribution of severity of lumbopelvic pain (LPP) in well-functioning older adults to poorer walking efficiency, lack of endurance, slower gait speed, and decline in these mobility parameters over 1 to 5 years. Design: Longitudinal analysis of Baltimore Longitudinal Study of Aging data. Setting: National I...
Article
Background: Higher amyloid burden predicts gait slowing in aging. Whether and which gait characteristics are associated with amyloid burden is less clear. Gait variability may be more sensitive to amyloid burden than mean gait characteristics. Methods: In the Baltimore Longitudinal Study of Aging, 99 older participants without neurological disea...
Article
Background: Fatigue is prevalent and distressing among cancer survivors, but its subjective nature makes it difficult to identify. Fatigability, defined as task-specific fatigue, and endurance performance may be useful supplemental measures of functional status in cancer survivors. Methods: Fatigability, endurance performance, and cancer history...
Article
Commonly used measures of physical activity (PA) fail to account for heterogeneity in maximal capacity between individuals. Utilizing the concept of heart rate reserve, we estimated minute level physical exertion (PE) among BLSA subjects with at least 3 days of Actiheart data (n = 411). Subjects’ average time spent in each of sedentary, light, mode...
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The negative impact of fear of falling (FoF) in older persons is postulated to be due to FoF-induced activity restriction (FoF-ActRes) leading to physical deconditioning. However, there is sparse direct evidence to support this. Therefore, we identified differences in key factors representing physical deconditioning between older adults who reporte...
Article
From biosciences to social sciences, mobility is emerging as a core indicator of health and aging. In animal models, scientists studying the molecular underpinnings of aging have moved beyond longevity to assess “healthspan”, often based on mobility indicators. Human studies continue to elucidate the causes and consequences of dysmobility. In healt...
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The Successful AGing after Elective Surgery (SAGES; P01AG031720) study is a unique longitudinal cohort examining the pathophysiology and long-term outcomes of delirium among older persons (N = 566; age 70+ years), followed for 3–6 years. The study features several strengths and innovations. It utilizes state-of-the-art measurement of the incidence,...
Article
Resilience and reserve are related. Resilience can be conceived of as tolerance to challenge, while reserve represents excess capacity. Both can be assessed using performance measures that extend the ability to discriminate levels of health. Resilience can be assessed by challenge tests such as dual task protocols while reserve can be assessed by a...
Article
Physical activity protects against functional decline; whether and what type of physical activity reduces and/or preserves fatigability is unknown. We evaluated the relationship between vigorous activity and habitual walking and the level and preservation of perceived fatigability (Borg rating of perceived exertion following 5 minutes of treadmill...
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Over the last decade and more, mobility has emerged as a fundamental indicator of health during aging, gaining attention from basic, clinical, social and health services researchers, as well as health care providers and systems. What is known, where are the most important gaps in knowledge, and what are the highest impact opportunities for future w...
Conference Paper
Low daily physical activity has been linked to poor health and functional performance with aging. However, the health implications of the daily patterns/temporal accumulation of physical activity remain unknown. We created an activity fragmentation index (AFI) to account for the number and duration of daily active bouts using 7-day accelerometry da...
Article
Traditional physical activity metrics include reported time spent in various levels of exertion, from sedentary to vigorous. Previous research has shown an association between time spent in moderate or vigorous activities and maximal aerobic capacity (VO2 max) in older adults, but the association between accelerometry derived activity metrics and V...
Data
Table S1 Selected characteristics given as mean (SD), comparing the excluded participants who were missing walking task data (n = 10), with those who had completed walking task data. Table S2 Linear regression models for kPCr rates predicting left thigh muscle cross‐sectional area, muscle strength, and muscle quality, adjusted for age, sex, height...
Article
Corresponding author at: Department of Neurophysiology, Rouen University Hospital, 76000 Rouen, France.
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Background Vestibular inputs have been shown to play a critical role in spatial navigation. In this study, we sought to evaluate whether vestibular loss due to aging contributes to impaired spatial navigation as measured by the triangle completion task (TCT).Materials and methodsWe recruited three types of participants: young controls <55 years of...
Article
While gait variability may reflect subtle changes due to aging or cognitive impairment (CI), associated brain characteristics remain unclear. We summarize structural and functional neuroimaging findings associated with gait variability in older adults with and without CI and dementia. We identified 17 eligible studies; all were cross-sectional; few...
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Background: Muscle quality (MQ) or strength-to-mass ratio declines with aging, but the rate of MQ change with aging is highly heterogeneous across individuals. The identification of risk factors for accelerated MQ decline may offer clues to identity the underpinning physiological mechanisms and indicate targets for prevention and treatment. Using...
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Skeletal muscle mitochondrial oxidative capacity declines with age and negatively affects walking performance, but the mechanism for this association is not fully clear. We tested the hypothesis that impaired oxidative capacity affects muscle performance and, through this mechanism, has a negative effect on walking speed. Muscle mitochondrial oxida...
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Objectives: We examined whether multiple domains of baseline cognitive performance were associated with prospective physical activity (PA) adherence in the Lifestyle Interventions and Independence for Elders Pilot study (LIFE-P). Design, setting, participants: The LIFE-P study was a single-blind, multicenter, randomized controlled trial of a PA...
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Objective: To determine whether compensatory saccade metrics observed in the video head impulse test, specifically saccade amplitude and latency, predict physical performance. Study design: Cross-sectional analysis of the Baltimore Longitudinal Study of Aging, a prospective cohort study. Setting: National Institute on Aging Intramural Research...
Article
Objective: To assess the importance and performance of consultant pharmacist services delivered before and after an intervention to detect and manage adverse drug events among nursing facility residents. Design: Before and after intervention survey of physicians participating in a randomized, controlled trial. Setting: Four nonprofit, academic...
Article
Background Age-related mobility limitations are debilitating and common. Cerebral white matter hyperintensities (WMH) and conditions affecting other systems are known contributors, but have been studied in isolation. Methods In 2,703 adults aged 65 years or older, we assessed cross-sectional and longitudinal gait speed and mobility disability (sel...
Article
Background Among older adults, both olfaction and motor function predict future cognitive decline and dementia, suggesting potential shared causal pathways. However, it is not known whether olfactory and motor function are independently related in late life. Methods We assessed cross-sectional associations of olfaction with motor and cognitive fun...
Article
Background We examined relationships between cerebral amyloid-beta (Aβ) and cognitive-gait dual-task performance in 27 cognitively normal, mobility unimpaired elders. Methods We assessed Aβ on Pittsburgh Compound B (PiB)-PET. We measured gait speed separately and while performing working-memory, response-inhibition, motor-sequencing, and phone-dia...
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Scattered evidence indicates that a lower basal body temperature may be associated with prolonged health span, yet few studies have directly evaluated this relationship. We examined cross-sectional and longitudinal associations between early morning oral temperature (95.0-98.6 °F) and usual gait speed, endurance walk performance, fatigability, and...
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Whether individuals with insulin resistance but without criteria for diabetes exhibit reduced mitochondrial oxidative capacity is unclear; addressing this question could guide research for new therapeutics. We investigated 248 non-diabetic participants from the Baltimore Longitudinal Study of Aging (BLSA) to determine whether impaired mitochondrial...
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Objective: To examine the relationship between gait speed and prior 10 years interleukin-6 (IL-6) burden in older adults. We then assessed whether white matter characteristics influence this relationship. Methods: In 179 community-dwelling older adults, gait speed was assessed on an automated walkway and serum IL-6 was assayed on ELISA. Concurre...
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Introduction Most older individuals who experience mobility decline, also show cognitive decline, but whether cognitive decline precedes or follows mobility limitation is not well understood. Our goal is to examine the temporal sequence of mobility and cognition among initially unimpaired older adults. Methods Mobility and cognition were assessed e...
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Introduction: Macrostructural white matter damage (WMD) is associated with less uniform and slower walking in older adults. The effect of age and subclinical microstructural WM degeneration (a potentially earlier phase of WM ischemic damage) on walking patterns and speed is less clear. This study examines the effect of age on the associations of re...
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A U-shaped relationship between cognitive demand and gait control may exist in dual-task situations, reflecting opposing effects of external focus of attention and attentional resource competition. The purpose of the study was twofold: to examine whether gait control, as evaluated from step-to-step variability, is related to cognitive task difficul...
Article
Background. Motor slowing is associated with risk of Alzheimer’s disease (AD). Whether β-amyloid (Aβ) burden is associated with motor decline, independent of cognitive decline, is unknown. Methods. 59 cognitively unimpaired older participants had baseline PET-PiB scans and repeated measures of lower (usual gait speed, 400m time, Health ABC Physical...
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Background: Research suggests that the central nervous system (CNS) and mobility are closely linked. CNS-mediated mobility impairment may represent a potentially new and prevalent syndrome within the older adult populations. Interventions targeting this group may have the potential to improve mobility and cognition and prevent disability. Methods:...
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In May 2015, the Cancer and Aging Research Group, in collaboration with the National Cancer Institute and the National Institute on Aging through a U13 grant, convened a conference to identify research priorities to help design and implement intervention studies to improve the quality of life and survivorship of older, frailer adults with cancer. C...
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Objectives: To explore the association between rate of physical health deterioration, operationalized as rising multimorbidity overtime, and longitudinal decline in cognitive function in older adults without dementia. Design: Longitudinal (Baltimore Longitudinal Study of Aging (BLSA)). Setting: Community. Participants: BLSA participants aged...
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Background: The impact of excess weight on current and future walking endurance in nondisabled persons is unclear. This study examines the association between obesity and walking endurance among nondisabled persons both in late mid-life and early old age. Methods: Participants in the Baltimore Longitudinal Study of Aging aged 60–79 years (n = 406)...
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Background: Age-related changes in testosterone levels in older persons and especially in women have not been fully explored. The objective of this study was to describe age-related trajectories of total testosterone (TT), ammonium sulfate precipitation-measured bioavailable testosterone (mBT), and sex hormone-binding glycoprotein (SHBG) in men an...
Article
Background: Lower integrity of cerebral gray matter is associated with higher gait variability. It is not known whether gray matter integrity is associated with higher lap time variation (LTV), a clinically accessible measure of gait variability, high levels of which have been associated with mortality. This study examines the cross-sectional asso...
Article
Background: White matter hyperintensities (WMH), a common marker of cerebral small vessel disease, and lower microstructural integrity of normal-appearing white matter are associated with slower gait. How these cerebral measures interact in relation to slower gait is unknown. We assessed whether microstructural integrity of normal-appearing white...
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Objectives: To compare the relative predictive power of handgrip and leg extension strength in predicting slow walking. Design: Report of correlative analysis from two epidemiological cohort studies. Setting: Foundation of the National Institutes of Health Sarcopenia Project. Participants: Men and women aged 67 to 93 (N=6,766). Measurements...