Measured Gait Speed Research Articles

Exploring the influence of body movements on spatial perception in landscape and interior design

This study investigates the influence of body movements on spatial perception in both landscape and interior design environments, focusing on how physical interactions shape spatial understanding beyond visual perception alone. Grounded in the theory of embodied cognition, the research examines how gait, posture, and movement dynamics affect spatial awareness. The study captures detailed data on movement patterns and visual engagement across different spatial contexts using a combination of real-world observations and Virtual Reality (VR) simulations, motion-tracking systems, wearable sensors, and eye-tracking technology. A total of 157 participants, aged 20 to 65, navigated both outdoor landscapes and indoor environments, with key variables such as surface materials, spatial layout, and lighting conditions manipulated to assess their effects on spatial perception. The study measured gait speed, step frequency, path deviations, time to destination, visual attention, and subjective ratings of perceived openness, ease of movement, and emotional response. Key findings include that surface materials significantly influenced gait speed and step frequency. For example, participants walking on concrete had a significantly faster gait speed (mean difference = 0.5220, p = 0.001) than those walking on gravel. In terms of spatial layout, the two-way Analysis of variance (ANOVA) results showed that winding paths led to more path deviations (F-statistic = 350.00, p = 3.19 × 10−8) and longer times to destination (F-statistic = 1744.00, p = 2.39 ´ 10−11) compared to straight paths. The environment type (landscape vs. interior) also significantly affected navigation, with landscape participants showing a more significant deviation from direct paths (F-statistic = 19.60, p = 2.37 × 10−3). Visual engagement data, analyzed through a chi-square test, indicated that vertical elements like walls approached significance in attracting visual attention (Chi-square = 2.88, p = 0.0896), while other elements like trees and benches had less impact. The Wilcoxon signed-rank test results showed significant differences between real-world and VR experiences in perceived openness (W-statistic = 0.0, p = 0.001953), ease of movement (W-statistic = 0.0, p = 0.001953), and comfort (W-statistic = 0.0, p = 0.001953), highlighting VR’s limitations in replicating the full embodied experience of physical spaces.

Associations of 2 Established Methods of Measuring Gait Speed and Sit-To-Stand Performance With Frailty and Life-Space Mobility in Community-Dwelling Older Adults

ObjectivesThe 4-m gait speed (4mGS) and 10-m gait speed (10mGS) tests and the 30-second sit-to-stand (30sSTS) and 5-times sit-to-stand (5xSTS) tests are commonly used and advocated in consensus recommendations. We compared these tests on their predictive and clinical value concerning the risk of prefrailty/frailty and restricted life-space mobility (RLSM). DesignCross-sectional study. Setting and ParticipantsA sample of 1235 community-dwelling adults (mean ± SD, 68 ± 7 years) participated in this prospective cohort study. MethodsAt baseline assessment, participants completed a survey and functional assessment, from which gait speed, sit-to-stand performance, self-reported mobility limitation, 40-item Frailty Index, and Life Space Assessment were measured. Participants with a 40-item Frailty Index >0.15 and a Life Space Assessment <60 points were classified as having prefrailty/frailty and RLSM, respectively. At 1-year follow-up assessment, prefrailty/frailty and RLSM were evaluated. ResultsCorrelations between gait speed and sit-to-stand measures were high (ρ values >0.80). In multivariable ordinal models, these measures added incremental prognostic value beyond a base model comprising demographics and self-reported mobility limitation variables in predicting baseline and 1-year outcomes. Between 10mGS and 4mGS, models with 10mGS had higher concordance indices (differences, 0.005-0.009), and these differences translated to generally greater net benefit in decision curve analyses. Between 30sSTS and 5xSTS measures, no one measure consistently outperformed the other, with small net benefit differences between measures (<0.2%). Conclusions and ImplicationsIn community-dwelling older adults, gait speed and sit-to-stand measures meaningfully predicted prefrailty/frailty and RLSM. 10mGS provided more robust prognostic information than the 4mGS, whereas 5xSTS and 30sSTS measures showed near equivalence of performance. These findings could guide the choice of functional measures in clinical and research settings.

The Importance of Racially and Ethnically Inclusive Gait Speed Reference Values in Individuals 90 Years and Older: LifeAfter90.

Clinicians use reference values to contextualize physical performance scores, but data are sparse in individuals 90years and older and racial/ethnic diversity is limited in existing studies. Gait speed provides valuable information about an individual's health status. Slow gait speed is associated with falls, cognitive decline, and mortality. Here, we report gait speed reference values in a racially/ethnically diverse oldest-old cohort. LifeAfter90 is a multiethnic cohort study of individuals 90years and older. Participants are long-term members of an integrated healthcare delivery system without a dementia diagnosis at enrollment. We assessed gait speed using the 4-m walk test and calculated means, standard deviations, and percentiles by age, sex, assistive device use, and device type. We used linear regression to compare means by sex, age, device use and type, living situation and arrangement, and race/ethnicity. The mean age of the 502 participants was 92.9 (range 90.1-102.8) years. Of these, 62.6% were women, 34.7% were college educated, 90.8% lived in a private residence, 20.9% self-reported as Asian, 22.5% as Black, 11.8% as Hispanic, 35.7% as White, and 9.2% as multiple, "other," or declined to state. The overall mean gait speed was 0.54 m/s (women=0.51 m/s, men=0.58 m/s). Mean gait speeds were 0.58 m/s, 0.53 m/s, and 0.48 m/s in the 90 to 91, 92 to 93, and 94+ age categories, respectively. In those without a device, mean gait speed was 0.63 m/s compared to 0.40 m/s in those with a device (cane=0.44 m/s, walker=0.37 m/s). Mean gait speed was significantly slower in women compared to men, age category 94+ compared to 90 to 91, participants with a device compared to those without, participants with a walker compared to a cane, and Black participants compared to Asian and White participants. However, differences by race/ethnicity were attenuated when chronic health conditions were considered. Reference values developed from this multiethnic 90+ cohort will help clinicians interpret gait speed measures and tailor recommendations toward a 90+ population that is growing in number and in racial/ethnic diversity.

Longitudinal association between dentition status and gait speed among older Brazilian adults: SABE cohort study

BackgroundOral health has been associated with general health conditions, but few longitudinal studies evaluated the effect of dentition status on gait speed.ObjectiveThis study aimed to investigate the longitudinal association between different time-varying measures of dentition status (i.e., number of teeth, the presence of periodontal pockets and the functional impact of oral health) and gait speed (outcome) in older Brazilian adults.Materials and methodsThis was a prospective study using data from the Health, Well-being and Aging cohort study (SABE) from 2006, 2010 and 2015. The gait speed was the dependent variable and the independent variables of interest were dentition status evaluated using the number of teeth, use of dental prostheses, presence of periodontal pocket, clinical attachment loss and self-perceived poor functional oral health. Dentition status measures were obtained through clinical oral examinations, performed by trained dentists using standardized criteria proposed by the World Health Organization. Self-perceived poor functional oral health was evaluated using the functional domain of the Geriatric Oral Health Assessment Index. The longitudinal effect of dentition status on gait speed was evaluated using mixed-effects linear models. The effect of the number of teeth/periodontal pocket/attachment loss on gait speed change over time was evaluated by including an interaction term between these variables. The effect of periodontal pocket was tested only among dentate individuals.ResultsData for the complete sample included 3,306 observations from 1,964 individuals. The analyses for dentate individuals included 1,883 observations from 1,149 individuals. There was a positive association between the number of teeth and mean gait speed. Individuals using dental prostheses also had higher means of gait speed than those without dental prostheses. Gait speed was lower among individuals with periodontal pockets and with attachment loss. No interaction was found between any of the indicators of dentition status and time.ConclusionGait speed was associated with dentition status and this association was constant over time.

GaitKeeper: An AI-Enabled Mobile Technology to Standardize and Measure Gait Speed.

Gait speed is increasingly recognized as an important health indicator. However, gait analysis in clinical settings often encounters inconsistencies due to methodological variability and resource constraints. To address these challenges, GaitKeeper uses artificial intelligence (AI) and augmented reality (AR) to standardize gait speed assessments. In laboratory conditions, GaitKeeper demonstrates close alignment with the Vicon system and, in clinical environments, it strongly correlates with the Gaitrite system. The integration of a cloud-based processing platform and robust data security positions GaitKeeper as an accurate, cost-effective, and user-friendly tool for gait assessment in diverse clinical settings.

Effects of various exercise interventions on motor function in cerebral palsy patients: a systematic review and network meta-analysis.

A network meta-analysis was utilized to compare the rehabilitative effectiveness of different exercise interventions on motor function in cerebral palsy(CP) patients. Computer searches were conducted across 9 databases, including PubMed, Cochrane Library, Scopus, Web of Science, Embase, and others, to identify randomized controlled trials focusing on different exercise interventions aimed at enhancing motor function in CP patients. The search spanned from the inception of the databases to January 31, 2024. 20 articles, encompassing 570 patients and evaluating three types of exercise interventions, were included in the analysis. Results showed that aerobic training, resistance training, and mixed training exhibited superior outcomes compared to the control group, as evidenced by improvements in Gross Motor Function Measure scores, muscle strength, gait speed, and 10-Meter Walk Test scores (P < 0.05). Furthermore, the network meta-analysis revealed that resistance training ranked highest in enhancing gross motor function and gait speed among CP patients, while mixed training was deemed most effective in improving muscle strength and 10-Meter Walk Test scores. Exercise interventions have been shown to significantly improve motor function in CP patients. Among these, resistance training and mixed training stand out for their effectiveness in enhancing walking capabilities. Resistance training is specifically aimed at improving gross motor function, while mixed training focuses on increasing muscle strength.

Prevalence and factors associated with probable sarcopenia in southern Brazil: a population-based study.

There are few studies on probable sarcopenia in rural areas. This study aims to assess prevalence of probable sarcopenia and its associated factors in older adults living in the rural area of a municipality in southern Brazil. This cross-sectional study assessed data from the second wave of the EpiRural Cohort Study. Structured questionnaires, handgrip strength, gait speed, and anthropometric measurements were collected from 651 older adults. The criteria from the European Working Group on Sarcopenia in Older People 2 were used in this study. Chi-square test and logistic regression with robust variance were performed. Prevalence of probable sarcopenia was 19.2% (95% confidence interval (CI): 16.3-25.2%). Male sex (prevalence ratio (PR) 1.61; 95%CI 1.17-2.21), age &ge;80 years (PR 4.15; 95%CI 2.65-6.50), underweight (PR 1.90; 95%CI 1.23-2.93), diabetes mellitus (PR 1.80; 95%CI 1.20-2.73), and hospitalization in the past year (PR 2.00; 95%CI 1.36-2.91) were significantly associated with probable sarcopenia. One in five rural older adults have probable sarcopenia. Older adults living in rural areas need frequent measurements of muscle strength, and greater investments should be made to minimize the physical disability caused by sarcopenia among this population.

Associations between brain structure and dual decline in gait and cognition

Dual decline in gait and cognition is associated with an increased risk of dementia, with combined gait and memory decline exhibiting the strongest association. To better understand the underlying pathology, we investigated the associations of baseline brain structure with dual decliners using three serial gait speed and cognitive assessments in memory, processing speed-attention, and verbal fluency. Participants (n=267) were categorized based on annual decline in gait speed and cognitive measures. Lower gray and white matter volume and higher white matter hyperintensity volume increased the risk of being a dual decliner in gait and both the memory and processing speed-attention groups (all p < 0.05). Lower hippocampal volume (p = 0.047) was only associated with dual decline in gait and memory group. No brain structures were correlated with dual decline in gait and verbal fluency. These results suggest that neurodegenerative pathology and white matter hyperintensities are involved in dual decline in gait and both memory and processing speed-attention. Smaller hippocampal volume may only contribute to dual decline in gait and memory.

Gait Performance and Brain Activity Are Improved by Gait Automatization during Robot-Assisted Gait Training in Patients with Burns: A Prospective, Randomized, Single-Blinded Study.

Background: Patients with lower extremity burn injuries have decreased gait function. Gait dysfunctions are compensated by activation of executive areas such as the prefrontal cortex (PFC). Although robot-assisted gait training (RAGT) can improve gait function, the training mechanisms of RAGT are unknown. We aimed to determine the clinical effects of RAGT in patients with burns and investigate their underlying mechanisms. Methods: This single-blind, randomized controlled trial involved 54 patients with lower extremity burns. The RAGT group underwent RAGT using SUBAR® and conventional training. The control (CON) group underwent only conventional training. The primary outcome was cortical activity measured using a functional near-infrared spectroscopy device before and after 8 weeks of training to confirm the compensatory effect of gait dysfunction. The secondary outcomes were the functional ambulation category (FAC) to evaluate gait performance, 6-min walking test (6 MWT) distance to measure gait speed, isometric force and range of motion (ROM) of lower extremities to evaluate physical function, and the visual analog scale (VAS) score to evaluate subjective pain during gait. Results: PFC activation during the gait phase in the RAGT group decreased significantly compared with that of the CON. The VAS score decreased and FAC score improved after 8 weeks of training in both groups. The 6 MWT scores, isometric strengths (the left knee flexor and bilateral ankle plantar flexors), and the ROMs (the extensions of bilateral hip and bilateral knee) of the RAGT group were significantly improved compared with those of the CON. RAGT improved gait speed, lower extremity ROMs, and lower extremity muscles strengths in patients with burns. Conclusions: The improvement in gait speed and cerebral blood flow evaluation results suggests that the automatization of gait is related to the treatment mechanism during RAGT.

Serial gait speed measurements over time and dynamic survival prediction in older adults

BackgroundA one-time gait speed measurement predicts mortality risk. A framework for updating a clinician’s mortality risk perception with new information from each clinic visit is needed. We used joint modeling of longitudinal and survival data for dynamic prediction of mortality risk. MethodsWe fit sex-stratified joint models to 20-meter (bi)annual longitudinal gait speed measured every 6 months and 14-year survival data from the Health, Aging and Body Composition Study allowing for non-linear fluctuations of gait speed and controlling for important covariates such as age, recent hospitalization, blood pressure, obesity, and comorbidities. ResultsParticipants (N = 3048) were 74 years old with gait speed 1.18 m/s. They were 42% Black, and 52% died over 14 years. Higher gait speed of 0.1 m/s was associated with 23% (95% confidence interval or CI = 20–25%) and 25% (CI = 21–28%) reductions in mortality risk in men and women; and a 0.05 m/s annualized slowing (slope) with 31% (CI = 13–51%) increase in men (all p < 0.05), with findings persisting after covariate adjustment. Distant gait speed history over a year prior contributed little for mortality risk prediction with mean change of only 1–2% in 5-year risk. ConclusionThe two most recent gait speeds appear sufficient to consider for mortality risk in the present initial analysis. More frequent gait speeds need to be considered in mortality risk prediction before definitive conclusions supporting real-world application.

2324 Feasibility of screening for frailty, sarcopenia and nutritional status in elective surgery for colorectal cancer

Abstract Introduction Preoperative frailty is a key determinant of post-surgical outcomes and often co-exists with sarcopenia and malnutrition. Older patients account for a significant proportion of patients undergoing surgery for colorectal cancer and are therefore more likely to be affected by these risk factors. Methods Patients aged 65 and over undergoing planned surgery for colorectal cancer were recruited across five sites. Participants were screened preoperatively using the Clinical Frailty Scale (CFS) and Groningen Frailty Indicator (GFI). Nutritional status was assessed using the short form mini nutritional assessment (MNA-SF) and participant collection of spot urine samples to objectively measure habitual dietary intake. Sarcopenia was assessed through grip strength, gait speed and psoas muscle measurement using preoperative CT imaging. The non-radiological screening measures were repeated eight-weeks postoperatively, with additional urine samples collected in the first and fourth weeks. Results Forty-three participants (mean age 76 years, 60% male) were recruited, of which 32% were frail. Using the mini-nutritional assessment 42% of participants were identified as at risk of malnutrition and 9% as malnourished. Urine assessment of habitual dietary intake is ongoing. There was a high prevalence of sarcopenia - 67% determined by hand grip strength and 42% by CT analysis. Mean length of stay following surgery was 6.9 days. 28% of participants were unable to complete the in-person post-operative follow up due to ill health, poor appetite and exhaustion. Conclusions This ongoing study has demonstrated the feasibility of incorporating frailty, nutritional status and sarcopenia screening alongside routine clinical care, in older adults undergoing surgery. However, retaining participants in observational studies during postoperative periods of convalescence, or whilst undergoing adjuvant treatment, is challenging. This study has also highlighted the potential of home urine sampling as a viable method of dietary assessment within community settings to aid malnutrition screening.

Balance, Strength, and Risk of Dementia: Findings From the Health and Retirement Study and the English Longitudinal Study of Ageing.

Slow gait speed has been consistently associated with an increased risk of dementia. This study examined whether measures of balance and lower limb strength are similarly related to the risk of developing dementia. Participants from the Health and Retirement Study (HRS, N = 5658, mean age = 73.23, standard deviation [SD] = 6.22) and the English Longitudinal Study of Ageing (ELSA, N = 3667, mean age = 69.90, SD = 7.02) completed measures of gait speed, semi-tandem balance, chair stand (ELSA only), and cognitive status at baseline. Cognitive status was assessed over up to 15 years. Baseline slower gait speed (hazard ratio [HR]HRS = 1.52, 95% confidence interval [CI] = 1.32-1.75, p < .001; HRELSA = 1.73, 95% CI = 1.37-2.18, p < .001); and balance impairment (HRHRS = 1.58, 95% CI = 1.26-1.96, p < .001; HRELSA = 1.97, 95% CI = 1.24-3.14, p < .01) were related to a higher risk of incident dementia, adjusting for demographic factors. The combination of slower gait and impaired balance was associated with a two-to-three times higher risk of dementia in HRS and ELSA. Worse performance on the chair stand at baseline was associated with a higher risk of dementia in ELSA (HR = 1.56, 95% CI = 1.23-1.99, p < .001). All performance measures remained significant when entered simultaneously and accounted for obesity, diabetes, blood pressure, physical activity, smoking, and depressive symptoms. There was little evidence that age, sex, or APOE ε4 moderated the association. Similar to gait speed, measures of balance and strength are associated with a higher risk of incident dementia. The findings have implications for clinical practice, given that these routinely used geriatric assessment tools are similarly related to dementia risk.

Effect of manual manipulation on mechanical gait parameters.

A variety of manual manipulation techniques are utilized in clinical practice to alleviate pain and improve musculoskeletal function. Many manual practitioners analyze gait patterns and asymmetries in their assessment of the patient, and an increasing number of gait motion capture studies are taking place with recent improvements in motion capture technology. This study is the first systematic review of whether these manual modalities have been shown to produce an objectively measurable change in gait mechanics. This study was designed to perform a systematic review of the literature to assess the impact of manual medicine modalities on biomechanical parameters of gait. A master search term composed of keywords and Medical Subject Headings (MeSH) search terms from an initial scan of relevant articles was utilized to search six databases. We screened the titles and abstracts of the resulting papers for relevance and then assessed their quality with the Cochrane Risk of Bias Tool. Clinical trials that featured both a manual manipulation intervention and multiple mechanical gait parameters were included. Case reports and other studies that only measured gait speed or other subjective measures of mobility were excluded. We included 20 studies in our final analysis. They utilize manipulation techniques primarily from osteopathic, chiropractic, massage, and physiotherapy backgrounds. The conditions studied primarily included problems with the back, knee, and ankle, as well as healthy patients and Parkinson's patients. Control groups were highly variable, if not absent. Most studies measured their gait parameters utilizing either multicamera motion capture systems or force platforms. Twelve of 20 papers included in the final analysis demonstrated a significant effect of manipulation on gait variables, many of which included either step length, walking speed, or sagittal range of motion (ROM) in joints of the lower extremity. However, the results and study design are too heterogeneous to draw robust conclusions from these studies as a whole. While there are initial indications that certain modalities may yield a change in certain gait parameters, the quality of evidence is low and there is insufficient evidence to conclude that manual therapies induce changes in biomechanical gait parameters. Studies are heterogeneous with respect to the populations studied and the interventions performed. Comparators were variable or absent across the studies, as were the outcome variables measured. More could be learned in the future with consistent methodology around blinding and sham treatment, and if the gait parameters measured were standardized and of a more robust clinical significance.

Speed- and Endurance-Based Classifications of Community Ambulation Post-Stroke Revisited: The Importance of Location in Walking Performance Measurement

Background Gait speed or 6-minute walk test are frequently used to project community ambulation abilities post-stroke by categorizing individuals as household ambulators, limited, or unlimited community ambulators. However, whether improved clinically-assessed gait outcomes truly translate into enhanced real-world community ambulation remains uncertain. Objective This cross-sectional study aimed to examine differences in home and community ambulation between established categories of speed- and endurance-based classification systems of community ambulation post-stroke and compare these with healthy controls. Methods Sixty stroke survivors and 18 healthy controls participated. Stroke survivors were categorized into low-speed, medium-speed, or high-speed groups based on speed-based classifications and into low-endurance, medium-endurance, or high-endurance groups based on the endurance-based classification. Home and community steps/day were quantified using Global Positioning System and accelerometer devices over 7 days. Results The low-speed groups exhibited fewer home and community steps/day than their medium- and high-speed counterparts (P < .05). The low-endurance group took fewer community steps/day than the high-endurance group (P < .05). Despite vast differences in clinical measures of gait speed and endurance, the medium-speed/endurance groups did not differ in their home and community steps/day from the high-speed/endurance groups, respectively. Stroke survivors took 48% fewer home steps/day and 77% fewer community steps/day than healthy controls. Conclusions Clinical classification systems may only distinguish home ambulators from community ambulators, but not between levels of community ambulation, especially beyond certain thresholds of gait speed and endurance. Clinicians should use caution when predicting community ambulation status through clinical measures, due to the limited translation of these classification systems into the real world.

Impact of Baseline Neuropathy Severity on Vutrisiran Treatment Response in the Phase 3 HELIOS-A Study.

Hereditary transthyretin (ATTRv, v for variant) amyloidosis is a rare, progressive, fatal disease with multisystem manifestations, caused by pathogenic variants in the transthyretin (TTR) gene. Vutrisiran, an RNA interference therapeutic that results in rapid TTR knockdown, improved neuropathy and quality of life (QOL) versus external placebo in patients with ATTRv amyloidosis with polyneuropathy in the phase 3 HELIOS-A study (NCT03759379). This post hoc analysis evaluates the impact of baseline neuropathy severity on response to vutrisiran treatment. Patients were randomized (3:1) to vutrisiran (n=122; 25mg subcutaneous injection once every 3months) or patisiran (n=42; 0.3mg/kg intravenous infusion once every 3weeks), which served as a reference group. In this post hoc analysis, patients were grouped into quartiles of increasing baseline Neuropathy Impairment Score (NIS): Quartile (Q)1≥5.0 to≤20.5; Q2>20.5 to≤44.1; Q3>44.1 to≤73.1; Q4>73.1 to≤127.0. Mean change from baseline to Month 18 was summarized by quartile for a range of efficacy endpoints. Across all baseline NIS quartiles, vutrisiran demonstrated benefit versus external placebo in measures of neuropathy severity (modified NIS+7), QOL (Norfolk Quality of Life-Diabetic Neuropathy), disability (Rasch-built Overall Disability Scale), gait speed (10-m walk test), and nutritional status (modified body mass index). Overall, patients in lower versus higher NIS quartiles (less severe neuropathy) at baseline maintained better scores at Month 18. The external placebo group progressively worsened in all measures at Month 18. Vutrisiran demonstrated benefit in neurologic function and other key efficacy measures versus external placebo across all four baseline neuropathy severity quartiles. Patients initiating vutrisiran earlier in their disease course retained the highest neurologic function level after 18months, highlighting the importance of early diagnosis and treatment. ClinicalTrials.gov: NCT03759379.

Validity and Reliability of a Smartphone Application for Home Measurement of Four-Meter Gait Speed in Older Adults.

The four-meter gait speed (4MGS) is a recommended physical performance test in older adults but is challenging to implement clinically. We developed a smartphone application (App) with a four-meter ribbon for remote 4MGS testing at home. This study aimed to assess the validity and reliability of this smartphone App-based assessment of the home 4MGS. We assessed the validity of the smartphone App by comparing it against a gold standard video assessment of the 4MGS conducted by study staff visiting community-dwelling older adults and against the stopwatch-based measurement. Moreover, we assessed the test-retest reliability in two supervised sessions and three additional sessions performed by the participants independently, without staff supervision. The 4MGS measured by the smartphone App was highly correlated with video-based 4MGS (r = 0.94), with minimal differences (mean = 0.07 m/s, ± 1.96 SD = 0.12) across a range of gait speeds. The test-retest reliability for the smartphone App 4MGS was high (ICC values: 0.75 to 0.93). The home 4MGS in older adults can be measured accurately and reliably using a smartphone in the pants pocket and a four-meter strip of ribbon. Leveraging existing technology carried by a significant portion of the older adult population could overcome barriers in busy clinical settings for this well-established objective mobility test.

USABILITY AND PSYCHOMETRIC PROPERTIES OF THE MOBITEC-GP APP FOR REAL-LIFE MOBILITY ASSESSMENT

Abstract Modern technologies such as the Global Navigation Satellite System and accelerometers which are integrated in every smartphone enable tracking mobility patterns over time, which in turn enables early detection of mobility impairments. Aim of the MOBITEC-GP project was to develop a mobile app which measures walking speed and spatial mobility under everyday conditions. Reliability and validity of the application was tested first (Study 1). The applicability in everyday life and the acceptance by older adults (Study 2) was also investigated. In study 1, participants underwent several supervised walking speed assessments as well as a 1-week life-space assessment during two assessment sessions 9 days apart. Fifty-seven older adults (47.4% male, mean age= 75.3 years) were included in the study. The app showed moderate to excellent test-retest reliability and validity of walking speed measurements of 50 meters and above and of most 1-week life-space parameters, including life-space area, time spent out-of-home, and action range. Study 2 revealed a good usability of the app (mean System Usability Scale score=77.18) among older adults (N=60 with ≥2 chronic conditions) for a 1-week usage of the app including both, a 1-week life space assessment and at least one gait speed measurement in a 30-minute stroll. The MOBITEC-GP app is a reliable, valid and usable tool for the assessment of real-life walking speed (at distances of 50 metres and above) and life-space parameters of older adults. Future studies should look into technical issues more systematically in order to avoid invalid measurements.

DEVELOPMENT OF A PHYSICAL PERFORMANCE SUMMARY SCORE IN MIDDLE AGE: FINDINGS FROM THE CARDIA FUNCTION ANCILLARY STUDY

Abstract Recent evidence suggests that ~20% of middle-aged adults report mobility limitations, supporting the need for assessment strategies to detect early-onset limitations, appropriate for this population. Coronary Artery Risk Development in Young Adults (CARDIA) enrolled 5,115 Black and White men and women ages 18-30 years from four sites (Birmingham, AL; Oakland, CA; Minneapolis, MN; and Chicago, IL) in 1985-86. The CARDIA Function Study added self-reported function (PROMIS SF20a) and 5 physical performance measures (gait speed, single-leg balance, lower extremity strength, grip strength, and 6-minute walk test) to the Year 35 in-person follow-up exam conducted in 2020-22. The CARDIA Physical Performance (CAPP) score was developed by calculating sex-specific quartiles separately for each performance measure, assigning points based on these quartiles (0 for not attempted, 1-4 for each quartile), and summing points across all 5 performance measures (range 0-20, higher scores = greater performance). Among 2,021 CARDIA Function participants [mean age: 60.1 (±3.6) years; 57% female; 45% Black] the mean CAPP score was 12.3 (±4.1; range 0-20). Mean CAPP scores differed by age &amp;lt; 60 vs. ≥60 years old (12.7 vs.12.1, p&amp;lt; 0.05) and self-reported function above vs. below the median SF20a score (14.0 vs. 10.6, p&amp;lt; 0.001), but as expected, not sex (12.3 vs. 12.3, p=0.99). Among middle-aged adults, the newly developed CAPP score captured a wide range of physical performance. Lower CAPP score was associated with lower than median self-reported function suggesting that the CAPP score may be helpful assessment tool for detecting early-onset limitations to attenuate functional declines with aging.

Validity, Reliability, and Feasibility of Smartphone Application Intended for Home Measurement of Gait Speed and Other Gait Dynamics in Older Adults with Blood Cancers

Introduction: Gait speed is a cardinal measure of mobility and frailty recommended to be assessed in all older adults with cancer (Dale, JCO, 2023). Four-meter gait speed (4MGS) is strongly predictive of mortality and hospitalization in older adults with hematologic malignancies (Liu, Blood, 2019). Remote monitoring technology can expand measurement of gait speed beyond the clinic (Clancy, JCO CCI, 2023), and smartphone applications (App) have been developed and validated to measure meaningful gait metrics via embedded internal motion sensors (Manor, JMIR Mhealth Uhealth, 2018). However, the validity and reliability of a smartphone App for remotely measuring gait speed in older adults is not known, nor is the feasibility of using an App to measure longitudinal gait speed in older adults with blood cancers. Methods: We conducted two studies to (1) determine the validity and reliability of a smartphone App in measuring 4MGS in community-dwelling older adults, and (2) determine the feasibility of measuring 4MGS weekly for six weeks in older adults with multiple myeloma (MM) and myelodysplastic syndromes (MDS). For the validity and reliability study, we enrolled adults aged ≥ 65 years living in an independent living housing facility. Each participant self-administered two supervised and three unsupervised gait assessments at home via the smartphone carried in their pocket, with the App providing multimedia instructions on how to complete the test. For each gait assessment, the participants walked back and forth along a 4-meter strip of ribbon for 45 seconds. For the first two supervised sessions, while the participants were self-administering the gait assessment, the study team concurrently captured their walking performance with a video camera (as a gold standard). For the following three unsupervised sessions, the participants administered the gait assessment App alone. We obtained the time for the first instance of walking along the 4-meter ribbon before turning and compared the gait speed (i.e. dividing 4 meters by the time) between the smartphone and the video capture. For the feasibility study, we enrolled patients age ≥73 years with either MDS or MM cared for at Dana-Farber Cancer Institute. Patients self-administered the gait assessment described above alone at home once a day for six weeks after a dedicated teaching session with study staff. We reported completion rates and participants' feedback regarding acceptability. Results: 14 older adults (77.2±6.3, 13 females) completed the validity and reliability study. The smartphone 4MGS demonstrated strong criterion validity yielding a high correlation with the camera 4MGS ( Figure 1) along with high reliability as demonstrated by high internal consistency and low measurement error ( Figure 2). The smartphone 4MGS also showed good test-retest reliability over three unsupervised sessions (intra-class correlation coefficient 0.78). In the feasibility study, 12 patients (79.3±3.14, 4 females, 50% MDS, 42% MM, and 8% both) were enrolled out of 19 contacted for recruitment (63%). To date, nine have completed the study: 9/9 completed at least one 4MGS test, 8/9 (89%) completed at least three weeks, and 3/9 (33%) completed all six weeks. When asked, “How important is measuring your function and mobility to you?” on a scale of 1 (low) to 5 (high), 7/9 participants answered 4 or 5. When asked to rate their experience completing the walking tests on a scale of 1 (very poor) to 5 (very good), 6/9 participants answered 4 or 5. When asked the degree to which one agrees with the statement, “I feel that the walking tests are too burdensome,” on scale of 1 (strongly disagree) to 5 (strongly agree), 9/9 patients answered 1 or 2. Conclusions: The App was both valid and reliable in measuring 4MGS in older adults' homes. User acceptance was also high, and the app was rated as minimally burdensome by patients with blood cancers with the majority completing at least three weekly home 4MGS tests. Our findings support using existing smartphone technology to assess a key measure of mobility and frailty in the homes of older adults with blood cancers, allowing for more frequent longitudinal assessment of how blood cancers and their treatments impact older adult mobility and frailty.

Identifying Geriatric Syndromes in Adults with Sickle Cell Disease Using the Sickle Cell Disease Functional Assessment (SCD-FA): The Sickle Cell Disease Functional Assessment Validation and Refinement (SILVR) Study

Introduction As people with sickle cell disease (SCD) age, they experience accelerated functional decline. Since historically survival for SCD has been limited to middle age, geriatric syndromes in adults with SCD remains understudied. Chronological age does not accurately represent a person's health status; thus, valid functional measures for adults with SCD are required. Geriatric assessments are commonly used to measure function in older adults in the general population. We previously demonstrated feasibility, safety, and acceptability of a geriatric assessment battery called the Sickle Cell Disease Functional Assessment (SCD-FA) in adults with SCD. The SCD-FA includes physical performance test and surveys evaluating multiple health domains. The purpose of this study was to evaluate the construct validity of the SCD-FA. Methods We enrolled younger (age 18-39) and older (age ≥ 40 years) adults with SCD in a single center prospective study. We assessed construct validity of each SCD-FA measure by determining known-group validity. Specifically, we evaluated whether the SCD-FA could distinguish between participants known to differ based on the following: age (&amp;lt; 40 vs ≥ 40), SCD genotype non-severe (HbSC/HbSβ +-thalassemia) vs severe (HbSS/HbSβ 0-thalassemia), and dependence in Activities of Daily Living/Instrumental Activities of Daily Living (no ADL/IADL deficit vs ≥ 1 ADL/IADL deficits). We used Student's t-tests and Wilcoxon rank sum test to gauge significant differences between groups. Results We performed the SCD-FA in 111 adults with SCD at steady state, with 93 (84%) having complete data. Most participants (58%) were female. The mean age of all participants was 44 ± 14 (range 19-82 years), with most (56%) age ≥ 40 years. The mean age for younger adults (18-39 years) was 30 ± 5.8 and 54 ± 9.3 for older adults (≥ 40 years). When evaluating SCD-FA measures by age, older adults had lower scores on PROMIS Physical Function (younger 52 ± 6.9 vs older 46 ± 8.4; p&amp;lt;0.001). Although there was no difference in number of falls by age, there were several participants with ≥ 1 fall (15%) or near fall (36%) in the last 6 months. Older adults had higher scores on the Social Support Survey (implying better support) (younger 69 ± 30 vs older 80 ± 20; p&amp;lt; 0.05). Older adults had more non-SCD comorbidities (younger 0.5 ± 0.7 vs older 1.7 ± 1.7; p&amp;lt;0.001), with no younger adults with ≥ 3 comorbidities vs. 33% of older adults with ≥ 3 comorbidities, more SCD conditions (younger 2.0 ± 1.5 vs older 2.7 ± 1.7; p&amp;lt; 0.05), and more reports of fair or poor hearing (0% younger vs 8% older; p = 0.01). Older adults took more prescribed medications (younger 3.9 ± 2.4 vs older 6.3 ± 3.9; p = 0.001) and were more likely to meet criteria for polypharmacy (defined as ≥ 5 prescribed medications) with 30% of younger adults vs 64% of older adults (Figure). Most participants (64%) had HbSS/HbSβ 0 (severe genotype) and 36% had HbSC/HbSβ + (non-severe genotype). When comparing groups by genotype, participants with severe genotypeshad a lower body mass index (severe25 ± 5.8 vs non-severe 31 ± 8.4 kg/m2; p &amp;lt; 0.005) and fewer non-SCD comorbidities (severe 0.75 ± 1.0 vs non-severe 1.9 ± 1.8; p&amp;lt; 0.005). There was no difference in physical performance, falls, psychological state, SCD conditions, and number of medications by genotypes. Of all participants, 34% reported dependence in ≥ 1 ADL/IADL. When comparing groups by ADL/IADL dependence, those who were dependent in ≥ 1 ADL/IADL had worse physical performance for all measures (gait speed, grip strength, 6-minute walk, Timed Up and Go test, and 30-Second Chair Stands). ADL/IADL dependent participants had more falls, higher PHQ-9 scores, lower MiniCog scores, more non-SCD comorbidities, and were more likely to report fair or poor vision. There was no difference in reported hearing deficits. (Table) Conclusion The SCD-FA was able to distinguish between known-groups by age and ADL/IADL dependence and identify deficits in adults with SCD such as falls, polypharmacy, comorbidities, and sensory deficits. Geriatric syndromes did increase with age in adults with SCD and were more common than in the general population (34% ADL dependent SCD participants vs 15% of middle-aged U.S. adults). Therefore, there is a need for early initiation of interventions to improve function and quality of life. We are currently adapting geriatric interventions for older adults with SCD. In future studies we will assess the predictive validity of the SCD-FA.