Toward a Better Understanding of Walking Speed in Ataxia of Charlevoix-Saguenay: a Factor Exploratory Study.

Mobility limitations, including a decrease in walking speed, are major issues for people with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS). Improving our understanding of factors influencing walking speed in ARSACS may inform the development of future interventions for gait rehabilitation and contribute to better clinical practices. The objective of the study was to identify the factors influencing the self-selected walking speed in adults with ARSACS. The dependent variable of this cross-sectional study was the self-selected speed and the factors (independent variables) were age, sex, balance, balance confidence, knee flexion and extension cocontraction indexes, lower limb coordination, passive range of motion of ankle dorsiflexion, knee and hip extension, and global spasticity. Multiple regression models were used to assess the relationships between walking speed and each factor individually. Six factors were significantly associated with walking speed and thus included in regression models. The models explained between 42.4 and 66.5% of the total variance of the self-selected walking speed. The factors that most influence self-selected walking speed are balance and lower limb coordination. In order of importance, the other factors that also significantly influence self-selected walking speed are ankle dorsiflexion range of motion, lower limb spasticity, knee extension range of motion, and confidence in balance. Balance and lower limb coordination should be targeted in rehabilitation interventions to maintain walking ability and functional independence as long as possible. The six factors identified should also be included in future studies to deepen our understanding of walking speed.

Could poor glycaemic control be a predictor of walking speed decline in older adults? Evidence from the English Longitudinal Study of Ageing.

AIM: Although diabetes is a risk factor for walking speed decline in older adults, it remains unclear how glycaemic control [assessed by glycated haemoglobin (HbA1c)] might affect the long-term trajectories of walking speed. We investigated whether the glycaemic control status accelerates the walking speed decline and whether this decline differs depending on previous mobility conditions. MATERIALS AND METHODS: In total, 3202 individuals aged ≥60 years from the English Longitudinal Study of Ageing (ELSA) were classified at baseline and after 4 and 8 years of follow-up according to glycaemic control status as 'without diabetes' (no self-reported diabetes and HbA1c <6.5%), 'good glycaemic control' (self-reported diabetes and HbA1c ≥6.5% and <7.0%) and 'poor glycaemic control' (PGC) (self-reported diabetes and HbA1c ≥7.0%). The generalized linear mixed models verified the walking speed trajectories in m/s. A second analysis was performed, including only participants without slowness at baseline (>0.8 m/s). RESULTS: Compared with the status 'without diabetes', the annual walking speed decline was -0.015 m/s for PGC and -0.011 m/s for good glycaemic control, totalling -0.160 and -0.130 m/s, respectively, over 8 years. Among those without slowness at baseline, only PGC had a significant walking speed decline, corresponding to -0.014 m/s per year and -0.222 m/s over 8 years. CONCLUSIONS: Poor glycaemic control is a discriminator of walking speed decline in older adults, regardless of previous mobility conditions. It may serve as an early screening tool for those at risk of decreased functional performance later in life.

Atrial fibrillation accelerates functional decline in older adults: a 15-year follow-up population-based study.

AIMS: Atrial fibrillation (AF) has been associated with functional impairment. However, the role exerted by AF on the long-term trajectories of functional mobility remains to be elucidated. This study aimed to evaluate the impact of AF on functional mobility by tracing walking speed (WS) trajectories over 15 years of follow-up in a population-based cohort of individuals aged 60+ years. METHODS AND RESULTS: This population-based cohort study included 3141 community-dwelling participants (mean age 73.7 years; 63.6% women) from the Swedish National Study on Aging and Care in Kungsholmen, who were regularly examined from 2001-2004 to 2016-2019. Functional mobility was assessed by measuring WS in a standardized way. The association between AF and WS trajectories was assessed by multivariable joint models accounting for the longitudinal dropouts due to death. Stratified analyses by demographic and clinical factors were performed. The effect-modifying role of oral anticoagulant therapy (OAC), incident heart failure (HF), and incident stroke was finally investigated. At baseline, 285 (9.1%) participants were ascertained to have AF. A faster annual WS decline was observed in persons with AF than in non-AF peers (adjusted ß coefficient per year = -0.011, 95% confidence interval: -0.016 to -0.005). Incident HF and stroke were associated with greater WS decline in participants with AF. OAC use was not associated with a slower functional decline. CONCLUSION: Atrial fibrillation is associated with a faster physical function decline in older individuals. Incident HF and stroke possibly accelerate WS decline over time in AF participants.

The effectiveness of bodyweight-supported treadmill training in stroke patients: randomized controlled trial.

OBJECTIVE: This study aimed to assess the impact of conventional rehabilitation (CR) and the combination of bodyweight-supported treadmill training (BWSTT) with CR on walking speed, endurance, balance, mobility, and the quality of life in stroke survivors. METHOD: In this prospective, randomized, controlled, and single-blind study, 30 stroke patients were included (ClinicalTrials.gov registration number: NCT04597658 date: October 22, 2020). These patients were divided into two groups: (1) CR only (control group, n = 14) and (2) CR with BWSTT (experimental group, n = 16). Both groups received CR for 3 consecutive weeks, 5 days a week, for 30 min each day. The experimental group received an additional 30 min of BWSTT per session. Patients were evaluated using the 10-m walk test (10MWT), the six-minute walk test (6MWT), the Tinetti Balance and Gait Assessment Score, the Timed Up and Go (TUG) test, the Rivermead Mobility Index (RMI), and the Stroke-Specific Quality of Life Scale (SS-QOL) before and after the intervention. RESULTS: Both groups showed significant improvements across all scales after the intervention. The BWSTT group exhibited particularly noteworthy enhancements in comfortable 10MWT and TUG scores (p = 0.043 and p = 0.025, respectively) compared to the CR group post-intervention. CONCLUSION: In conclusion, a holistic approach combining conventional physiotherapy with overground gait training can enhance various aspects of mobility. This approach offers a cost-effective and equipment-free alternative to BWSTT and necessitates specialized treadmill and bodyweight support systems, incurring higher costs. However, using BWSTT as a co-therapy therapy can be costly but provides additional benefits for enhancing functional mobility.

Function and activity capacity at 1 year after the admission to intensive care unit for COVID-19.

OBJECTIVE: To describe hand grip strength, walking speed, functional mobility, and postural control at one year following intensive care unit admission for COVID-19, and to find any predictors that are associated with impaired hand grip strength, walking speed, functional mobility, or postural control at the 1-year follow-up. DESIGN: Retrospective cross-sectional and longitudinal observational study. SETTING: Intensive care unit and outpatient research clinic at Sahlgrenska University Hospital. PARTICIPANTS: Of the 105 individuals in "The Gothenburg Recovery and Rehabilitation after COVID-19 and Intensive Care Unit" cohort, 78 participated in this study. MAIN MEASURES: Descriptive statistics for hand grip strength, walking speed, functional mobility, and postural control were presented and binary logistic regressions were performed to find their significant predictors. RESULTS: At 1-year following intensive care unit admission for COVID-19, impaired hand grip strength was found in 24.4% for the right hand and 23.1% for the left hand. Walking speed, functional mobility, and postural control were found to be impaired in 29.5%, 21.8%, and 5.1%, respectively. For impaired walking speed, longer length of stay at intensive care unit and presence of diabetes mellitus were risk factors. Diabetes mellitus was found to be the risk factor for impaired functional mobility. CONCLUSION: In this study, 45% of the participants showed impairment in function, activity capacity or both. These results suggest that individuals who recovered after intensive care unit admission for COVID-19 would benefit from receiving long-term follow-up to enable identification of those with need of physical health assistance and rehabilitation.

Walking net V ˙ O2 rises with advancing age in older women: where to go from here?

PURPOSE: Walking net V ˙ O2 tends to increase with advancing age; however, factors contributing to this relationship have not been widely described. The implications of such findings could inform targeted strategies to promote independent mobility in older adults. Herein, we evaluated the relationship between net V ˙ O2 and age at two submaximal workloads while exploring potential moderators of this relationship. METHODS: Secondary analyses were performed on 35 older (65 ± 3 years) women who completed a battery of physical assessments including fixed-speed, non-graded and graded (+ 2.5%) treadmill walking with indirect calorimetry to determine net V ˙ O2. Maximal oxygen uptake ( V ˙ O2max), knee extensor maximal isometric voluntary contraction (MVC), peak rate of torque development (RTD), and plantar flexor range-of-motion (PFROM) were also measured. RESULTS: Bivariate correlations showed non-graded (r = 0.403, p = 0.017) and graded (r = 0.413, p = 0.014) net V ˙ O2 were positively related to age. Notably, these relationships strengthened after adjusting for V ˙ O2max. Regression modeling showed age, RTD:MVC ratio (composite of muscle performance), and PFROM together explained 49% and 34% of the variance in non-graded and graded net V ˙ O2, respectively. Further analyses suggested knee extensor MVC moderates the relationship between non-graded net V ˙ O2 and age, accounting for 9% of the variance [ΔR2 = 0.090, F (1,31) = 4.13, p = 0.05]. CONCLUSION: These data support the premise that, in older women, walking net V ˙ O2 rises with advancing age, and additionally, the RTD:MVC ratio and PFROM are independent correlates of non-graded net V ˙ O2. Exercise interventions with a high degree of training specificity including explosive, velocity-based elements may promote independent mobility in older women.

Independent and combined associations of handgrip strength and walking speed with cognitive function in older adults: evidence from a national cross-sectional study.

OBJECTIVES: Although there have been studies on the association of handgrip strength or walking speed alone with cognitive abilities, few studies have determined the combined associations of handgrip strength and walking speed with cognitive function. Therefore we aimed to explore the independent and combined associations of handgrip strength and walking speed with cognitive function in Chinese older adults using a nationally representative sample. METHOD: This cross-sectional study included 4,577 adults aged 60 and older. Handgrip strength was measured using a dynamometer and walking speed was assessed using a 2.5-meter walking test. Both handgrip strength and walking speed were organized into low, normal, and high tertiles according to the sample distribution. Cognitive function was measured using the Telephone Interview for Cognitive Status. RESULTS: Handgrip strength and walking speed were significantly associated with cognitive function. Participants with low handgrip strength or low walking speed separately had a higher rate of lower cognitive function (adjusted odds ratio (OR): 1.22 (95% CI: 1.04 - 1.44) for low handgrip strength; 1.54 (95% CI: 1.31 - 1.81) for low walking speed). Those with both low handgrip strength and low walking speed had an additively higher rate of lower cognitive function (adjusted OR: 1.72 (95% CI: 1.32 - 2.24)). CONCLUSION: Having low handgrip strength or low walking speed is associated with a greater likelihood of lower cognitive function and vice versa. The concurrence of having low handgrip strength and low walking speed has an additive effect on cognitive function in older adults.

Dose-response association between walking speed and all-cause mortality: A systematic review and meta-analysis of cohort studies.

This review aims to investigate the dose-response relationship between walking speed and all-cause mortality. PubMed, Web of Science, Embase and Cochrane Library were searched to September, 2023 for cohort studies. A meta-analysis estimated the overall hazard ratio (HR) of mortality incidence and 95% Confidence Interval (CI) for individuals with the fastest walking speed compared to those with the slowest walking speed. Subgroup analyses were conducted based on sex, age and speed-measuring methods. Dose-response meta-analyses were examined by using "mvmeta" packages available in STATA. A total of 13 studies involving 530,841 participants were included. Of these, 11 studies provided data for dose-response meta-analyses. Individuals in the fastest walking-speed category had a 43% lower risk of all-cause mortality compared to those in the slowest walking-speed category (HR = 0.57, 95% CI 0.48-0.66). There was an inverse linear dose-response relationship between walking speed and all-cause mortality; for every 0.1 m/s increment in walking speed, the risk of mortality decreased by 6% (HR = 0.94; 0.92-0.96). There was an inverse nonlinear dose-response relationship between them when participants' age was larger than 65 years, but linear dose-response relationships were detected in both the timed walking speed test and self-reported walking speed measurements.

Effect of Protein Supplementation Combined With Resistance Training in Gait Speed in Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: We aimed to evaluate the effectiveness of the combination of protein supplementation and resistance training (RT), compared with RT alone or combined with a placebo, in improving gait speed. METHODS: We searched PubMed, Web of Science, Cochrane Library, and SPORTDiscus databases, and 18 randomized controlled trials with 1,147 older participants were included for meta-analysis. Data were pooled as the effect sizes (Hedges' g) with 95% confidence interval (CI) of the gait speed (in meters per second). The random-effect meta-analysis, subgroup analyses, meta-regression, and sensitivity analysis were conducted. RESULTS: The combination of protein supplementation and RT significantly improved gait speed (Hedges' g: 0.52 m/s, 95% confidence interval [0.17, 0.86], p = .005; I2 = 86.5%) compared with the RT alone. The subgroup analyses revealed that the significant improvement in gait speed postprotein intervention plus RT was observed only in participants who consumed protein after RT (Hedges' g: 0.90 m/s, 95% confidence interval [0.46, 1.33], p = .001; I2 = 79.6%). The pooled result did not significantly change after excluding any single study at one time or excluding smaller studies with large effect sizes. CONCLUSIONS: Protein supplementation combined with RT could significantly improve the gait speed of older adults compared with RT alone. This positive effect is more pronounced in people who consume protein after RT.

Association Between Typologies of Sedentary Behavior and Muscle Strength, Gait Speed, and Balance in Community-Dwelling Older Adults.

Knowledge of how the different types of sedentary behaviors (SB) are associated with functional limitations can guide professionals who work with older adults on better recommendations about the amount of daily time that should be encouraged in each type of SB. The objective was to estimate the associations between two SB typologies (SB television [TV] and SB computer/internet) and the presence of handgrip strength, lower limb strength, gait speed, and balance limitations in Brazilian community-dwelling older adults. This is a cross-sectional study with 1,298 community-dwelling older adults (≥60 years). SB was assessed by self-reporting daily time spent watching TV or using computer/internet (categorized into <2, 3-4, and ≥5 hr/day). Outcomes were handgrip strength, lower limb strength, gait speed, and balance limitations considering referenced cutoff points. Older adults in SB TV ≥5 hr/day had 1.75 (95% confidence interval [CI] [1.07, 2.86]) and 1.88 (95% CI [1.02, 3.46]) times more chances of handgrip strength and gait speed limitations, respectively. On the other hand, those who spent 3-4 and ≥5 hr/day in SB computer/internet had 0.45 (95% CI [0.20, 0.99]) and 0.37 (95% CI [0.15, 0.93]) had less chances of lower limb strength and balance limitations, respectively. In conclusion, functional limitations would be associated differently depending on the type of SB in the older adults sampled.

Sex differences in the association of physical functions with hospitalization and mortality events among community-dwelling older adults with disabilities.

This study aimed to investigate the role of sex in the association between physical function and the occurrence of hospitalization and mortality among community-dwelling older adults with impairments in activities of daily living (ADL). Participants included community-dwelling older adults aged ≥65 years with ADL disabilities. Physical functions (hand grip strength [HGS], knee extension muscle strength, and comfortable walking speed [CWS]) were measured at baseline and analyzed for association with hospitalization and mortality by sex using Cox regression analysis, adjusted for potential confounders. In this Cox regression analysis, HGS was significantly associated with the occurrence of hospitalization and mortality in women, whereas CWS was significantly associated with the occurrence of hospitalization and HGS with mortality in men. These findings reveal that the predictive ability of adverse events in community-dwelling older adults with disabilities differs by sex, requiring outcome- and sex-specific prognostication.

Comparison of the Influence of Dual-Task Activities on Prefrontal Activation and Gait Variables in Older Adults with Mild Cognitive Impairment during Straight and Curved Walking.

Background and Objectives: Mild cognitive impairment (MCI) is an early stage of dementia in which everyday tasks can be maintained; however, notable challenges may occur in memory, focus, and problem-solving skills. Therefore, motor-cognitive dual-task training is warranted to prevent cognitive decline and improve cognition in aging populations. This study aimed to determine the influence of such dual-task activities during straight and curved walking on the activities of the prefrontal cortex and associated gait variables in older adults with MCI. Materials and Methods: Twenty-seven older adults aged ≥65 years and identified as having MCI based on their scores (18-23) on the Korean Mini-Mental State Examination were enrolled. The participants performed four task scenarios in random order: walking straight, walking straight with a cognitive task, walking curved, and walking curved with a cognitive task. The activation of the prefrontal cortex, which is manifested by a change in the level of oxyhemoglobin, was measured using functional near-infrared spectroscopy. The gait speed and step count were recorded during the task performance. Results: Significant differences were observed in prefrontal cortex activation and gait variables (p < 0.05). Specifically, a substantial increase was observed in prefrontal cortex activation during a dual task compared with that during a resting-state (p < 0.013). Additionally, significant variations were noted in the gait speed and step count (p < 0.05). Conclusions: This study directly demonstrates the impact of motor-cognitive dual-task training on prefrontal cortex activation in older adults with MCI, suggesting the importance of including such interventions in enhancing cognitive function.

Influence of Education, Cognition, and Physical Disability on Quality of Life of Romanian Patients with Multiple Sclerosis-A Cohort Study.

Background and Objectives: objective measures of disability and neurological impairmentare used to search for disease activity and monitor disease evolution in multiple sclerosis (MS). These are sometimes in disagreement with subjective quality-of-life measures. We aimed to establish the relations between the Multiple Sclerosis Quality of Life instrument (MSQOL-54) and objective measures of neurological impairment. Materials and Methods: 107 patients with MS were evaluated with the Single Digit Modalities Test (SDMT) for cognition, Nine Holes Peg Test (9HPT) for upper limb function, 25 Feet Walk Test (25FWT) for gait, and EDSS for global disability in a cohort study. Age and education level were recorded as sociodemographic factors. Results: the median EDSS was 3.5 (IQR 2.5); average SDMT score was 30.38 ± 13.54; and 9HPT speed was significantly higher for the dominant upper limb (0.3 ± 0.1 pegs/s versus 0.28 ± 0.11 pegs/s) (p = 0.016). The mental health composite score of the MSQOL-54 correlated with the SDMT, education level, and EDSS. Education level correlated with cognition and quality of life. The physical health composite score of the MSQOL-54 correlated with motor-function parameters and with SDMT. The motor-function parameters correlated well among themselves. A linear regression model found an important influence of SDMT and education level on the mental health composite score of the MSQOL-54. Although the linear regression model predicting the physical health composite score from physical disability parameters was statistically sound, none of the determinants had a significant individual influence. Conclusions: the subscores of the MSQOL-54 correlated well with the objective parameters. The strongest correlations were those with the cognitive function. Correlations with physical disability were less powerful, probably reflecting their indirect and more limited influence on quality of life compared to cognition and perception of disability.

Long-term trajectories of ambulatory impairment in multiple sclerosis.

BACKGROUND: Ambulatory impairment is a common and complex manifestation of multiple sclerosis (MS), and longitudinal patterns are not well understood. OBJECTIVE: To characterize longitudinal walking speed trajectories in a general MS patient population and in those with early disease (⩽ 5 years from onset), identify subgroups with similar patterns, and examine associations with individual attributes. METHODS: Using a retrospective cohort study design, latent class growth analysis was applied to longitudinal timed 25-foot walk (T25-FW) data from 7683 MS patients, to determine T25-FW trajectories. Associations were evaluated between trajectory assignment and individual attributes. Analyses were repeated for 2591 patients with early disease. RESULTS: In the general patient population, six trajectories were discerned, ranging from very minimal to very high impairment at baseline, with variability in impairment accrual. The clusters with moderate to very high walking impairment were associated with being female, older and Black American, longer symptom duration, progressive course, and depressive symptoms. In the early disease subset, eight trajectories were discerned that included two subgroups that rapidly accrued impairment. CONCLUSION: We identified novel subgroups of MS patients will distinct long-term T25-FW trajectories. These results underscore that socially disadvantaged and economically marginalized MS patients are the most vulnerable for severe ambulatory impairment.

Chronic pain increases the risk of motoric cognitive risk syndrome at 4 years of follow-up: evidence from the China Health and Retirement Longitudinal Study.

BACKGROUND AND PURPOSE: Slower gait speed and subjective cognitive concerns are characteristics of the motoric cognitive risk (MCR) syndrome. This study aimed to examine if changes in pain may be hallmarks of early MCR, through investigating the magnitude of the association of chronic pain and the risk of MCR at 4 years follow-up. METHODS: In total, 3711 participants without dementia or any mobility disability aged ≥60 years were studied, including 1413 with chronic pain, enrolled in the China Health and Retirement Longitudinal Study, a prospective cohort study. MCR assessed at wave 1 (2011) and wave 3 (2015) was used as the exposure. Cox regression analysis was used to examine the longitudinal association between chronic pain and MCR after adjusting for individual factors, behaviors/physiology factors and societal factors. Four years later, the incident MCR was evaluated. RESULTS: After adjusting for individual factors, chronic pain was found to increase the risk of MCR development over time by about 1.5 times (hazard ratio 1.562, 95% confidence interval 1.228-1.986; p < 0.001) and to be linked with incident MCR at baseline (odds ratio 1.397, 95% confidence interval 1.149-1.698; p < 0.001). These associations remained substantial when behaviors/physiology factors and societal factors were taken into account in the analytical models. CONCLUSIONS: The findings of our study imply that incident MCR may be exacerbated by chronic pain. Further exploration is required to find out whether chronic pain is a modifiable risk factor for MCR.

Association between walking speed and calcaneus stiffness index in older adults.

INTRODUCTION: The aim here is to examine the association between objectively measured usual walking speed (UWS) and bone status in community-dwelling older Chinese. MATERIALS AND METHODS: This is a cross-sectional study of a population of 1528 adults (817 females, mean age 68.5 ± 5.3; 711 males, mean age 69.1 ± 5.2) aged 60-79, living in communities in Shanghai. Walking speed was assessed using a 4-m walk test at a usual-pace walking speed a walking speed at which the subject felt relaxed-and bone status measured by quantitative ultrasound (QUS). The health-related characteristics of participants include family background, physical activity level, chronic disease, smoking and alcohol consumption, frequency of falls, vitamin intake, and hormone therapy. RESULTS: Multiple linear regression is used to analyses any association between UWS and bone status, adjusting for confounding factors showing a significant association between faster UWS and a higher calcaneal stiffness index (SI) (p < 0.01). Comparing the lowest quartile of the data set with the highest at UWS, a high SI is achieved with 5.34 (95% CI = 3.22, 7.46) (p < 0.01), after adjusting for confounders. An increase of 1 dm/s was associated with a 0.91 (95% CI = 0.53, 1.29) increase in SI. This relationship for most subgroups is consistent. CONCLUSION: Our findings suggest that UWS can be a sensitive indicator of calcaneal bone loss among an older population.

Influence of transcutaneous electrical nerve stimulation on walking kinematics and standing balance of older adults who differ in walking speed.

The purpose was to determine the impact of transcutaneous electrical nerve stimulation (TENS) on measures of walking kinematics and standing balance of healthy older adults who were stratified into two groups based on differences in the distance walked during the 6-min test of walking endurance. Regression models were developed to explain the variance in the 6-min distance and to assess the predictive power of balance metrics to categorize the 26 older adults (72 ± 5.4 yrs) as either slow or fast walkers. Walking kinematics were measured during 6- and 2-min walk tests that were performed with and without the concurrent application of TENS to the hip flexor and ankle dorsiflexor muscles. Participants walked briskly during the 6-min test and at a preferred pace during the 2-min test. The supplementary sensory stimulation provided by TENS did not alter the power of the models to explain the variance in the Baseline 6-min distance: Baseline, R2 = 0.85; TENS, R2 = 0.83. In contrast, TENS improved the explanatory power of the data obtained during the 2-min walk to account for the variance in the Baseline 6-min distance: no TENS, R2 = 0.40; TENS, R2 = 0.64. Logistic regression models based on force-plate and kinematic data obtained during the balance tasks were able to discriminate between the two groups with excellent certainty. The impact of TENS was greatest when older adults walked at a preferred speed but not when they walked at a brisk pace or performed tests of standing balance.

Interactive Combinations Between Gait Speed and Physical Function at Acute Phase Can Predict the Physical Activity at 2 Years After Total Knee Arthroplasty Using Classification and Regression Tree Analysis.

OBJECTIVE: To clarify the interactive combinations of various clinical factors associated with physical activity (PA) at 2 years after total knee arthroplasty (TKA) using classification and regression tree (CART) analysis. DESIGN: A retrospective cohort study. SETTING: A single university hospital. PARTICIPANTS: 286 patients who underwent TKA (N=286). MAIN OUTCOME MEASURES: PA was assessed preoperatively, 3 weeks, and 2 years after TKA. Physical functions, namely, 10 m walking test (10MWT), timed Up and Go test, 1-leg standing time, isometric knee extension and flexion strength, knee joint stability, knee pain, femora-tibial angle, and the passive knee extension and flexion angle, were measured before surgery as a baseline and 3 weeks after TKA as acute phase. CART analysis was conducted to clarify the interactive combinations that accurately predict the PA at 2 years after TKA. RESULTS: The results of CART analysis indicated that gait speed (≥1.05 m/s) at the acute phase after TKA was the primal predictor for the postoperative PA at 2 years. The highest postoperative PA at 2 years was determined by gait speed (≥1.05 m/s) and PA (>74.5) at the acute phase. The PA at baseline and at acute phase, as well as the body mass index were also selected as predictors of postoperative PA at 2 years. CONCLUSION: The present study suggested that acquiring gait speed (≥1.05 m/s) and PA (>74.5) in the postoperative acute phase is the predictive of a high PA at 2 years after TKA.

Longitudinal Associations Between Falls and Risk of Gait Decline: Results From the Central Control of Mobility and Aging Study.

OBJECTIVE: To examine whether falls are associated with longitudinal changes in different gait domains and onset of clinical gait abnormalities. DESIGN: Longitudinal study. SETTING: General community. PARTICIPANTS: Ambulatory older adults free of dementia (N=428; mean age, 77.8±6.4 years). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Gait was assessed with a computerized walkway. Pace, rhythm, and variability (outcome measures) were derived from individual gait measures, using principal component analysis. Clinical gait abnormalities (neurologic, nonneurologic, mixed) were visually assessed by clinicians. Linear mixed-effects models were used to examine the associations between falls (the exposure variable coded as none, single, and multiple) and changes in gait domains. Multinomial logistic regression was used to examine associations between falls and the onset of clinical gait abnormalities. Models were adjusted for sex, education, age, body mass index, number of comorbidities, gait speed at the first follow-up, and time between the last fall and the first follow-up gait assessment. RESULTS: Pace declined while rhythm and variability increased at a faster rate (P<.05) among 32 participants with multiple falls in the first year of follow-up compared with 299 participants with no falls. Risk for clinical gait abnormalities between those with no falls, a single fall, or multiple falls was not different. CONCLUSIONS: Multiple falls predict future gait decline in multiple domains in aging. Interventions to prevent gait decline after multiple falls should be investigated.

Referent Values for Commonly Used Clinical Mobility Tests in Black and White Adults Aged 50-95 Years.

OBJECTIVE: To estimate referent values for performance on clinical mobility tests conducted amongst racially diverse adults aged 50-95 years in the Southeast US. DESIGN: This is an observational study of community-dwelling older adults from diverse racial groups who participated in observational and rehabilitative studies conducted from 2011-2019. SETTING: Rehabilitation clinics around the greater metropolitan Atlanta, Georgia, region. PARTICIPANTS: A total of 314 adults (N=314; 222 women). Individuals were predominantly Black (n=121) or White (n=164), with some participants from other racial groups (n=29). INTERVENTIONS: Clinical and demographic data were collected at individual visits for each participant. MAIN OUTCOME MEASURES: Four Square Step Test (FSST), timed Up and Go (TUG) test, dual TUG test, 6-minute walk test (6MWT), 30-second chair stand, and gait speed were all used as assessments in each cohort. RESULTS: Performance slowly declines with increasing age, with a sharp drop in the ninth decade for preferred forward, backward, and fast gait speed; backward gait cadence; 6MWT, TUG test, dual-task TUG-Cognitive, and the 360° turn test. Declines were also seen in the eighth and ninth decades in the FSST. Among White participants, there were significant overall differences across age groups except in the assessment variable, preferred gait cadence. For Black individuals, there were significant overall differences across age groups for backward gait speed, fast gait speed, TUG-Cognitive, dual task, 6MWT, FSST, and 30-second chair stand. CONCLUSIONS: These data enrich current referent values for brief, commonly used clinical tests in a diverse, older Southeast US cohort. These data include representatives of the oldest old cohort. This study will support race- and age-specific fall prevention and mobility-enhancing therapeutic application among older patients in clinical practice.