The association between peripheral neuropathy and daily-life gait quality characteristics in people with diabetes.

BACKGROUND: Peripheral neuropathy is a common complication of diabetes and increases the risk of falls, possibly through gait (quality) impairments in daily life. Characteristics of gait quality have been associated with peripheral neuropathy in a laboratory setting, but little is known about the more relevant association with gait quality in daily life. RESEARCH QUESTION: What is the association between peripheral neuropathy and gait quality characteristics in daily life in people with diabetes? METHODS: Data from two cross-sectional studies were combined in an exploratory analysis, including a total of 98 participants with diabetes (mean age: 68 (SD 7) years, 32 females), of which 68 with peripheral neuropathy. Participants wore a tri-axial accelerometer for seven consecutive days. Walking episodes ≥5 seconds were identified and analysed to determine various gait quality characteristics. Associations were assessed using linear regression analyses, adjusted for walking speed and other potential confounders. RESULTS: Peripheral neuropathy was significantly associated with a lower walking speed (people with neuropathy: 0.81 vs without neuropathy: 0.88 m/s; ß (95 % confidence interval (CI)): -0.114 (-0.202 to -0.026)), a lower stride frequency (0.81 vs 0.85 strides/s; ß (95 % CI): -0.030 (-0.057 to -0.003)), lower gait intensity (i.e. lower root mean square) in vertical direction (1.38 vs 1.63 m/s2; ß (95 % CI): -0.074 (-0.143 to -0.006)), and less gait symmetry (i.e. lower harmonic ratio) in vertical direction (1.82 vs 2.27; ß (95 % CI): -0.322 (-0.474 to -0.170)). People with peripheral neuropathy had non-significantly poorer gait quality for most of the other 21 gait quality characteristics. SIGNIFICANCE: Peripheral neuropathy seems to negatively affect several gait quality characteristics measured in daily life. These results need to be replicated in future studies and may help to develop targeted gait training to improve gait quality and potentially reduce fall risk in people with diabetes and peripheral neuropathy.

External Validation and Further Exploration of Fall Prediction Models Based on Questionnaires and Daily-Life Trunk Accelerometry.

Ambulatory measurements of trunk accelerations can provide valuable insight into the amount and quality of daily life activities. Such information has been used to create models to identify individuals at high risk of falls. However, external validation of such prediction models is lacking, yet crucial for clinical implementation. We externally validated 3 previously described fall prediction models. Complete questionnaires and 1-week trunk acceleration data were obtained from 263 community-dwelling people (mean age 71.8 years, 68.1% female). To validate models, we first used the coefficients and optimal cutoffs from the original cohort, then recalibrated the original models, as well as optimized parameters based on our new cohort. Among all participants, 39.9% experienced falls during a 6-month follow-up. All models showed poor precision (0.20-0.49), poor sensitivity (0.32-0.58), and good specificity (0.45-0.89). Calibration of the original models had limited effect on model performance. Using coefficients and cutoffs optimized on the external cohort also had limited benefits. Lastly, the odds ratios in our cohort were different from those in the original cohort, which indicated that gait characteristics, except for the index of harmonicity ML (medial-lateral direction), were not statistically associated with falls. Fall risk prediction in our cohort was not as effective as in the original cohort. Recalibration as well as optimized model parameters resulted in a limited increase in accuracy. Fall prediction models are highly specific to the cohort studied. This highlights the need for large representative cohorts, preferably with an external validation cohort.

Optimizing and Implementing a Community-Based Group Fall Prevention Program: A Mixed Methods Study.

Falls and fall-related injuries among older adults are associated with decreased health. Therefore, fall prevention programs (FPPs) are increasingly important. However, the translation of such complex programs into clinical practice lacks insight into factors that influence implementation. Therefore, the aim of this study was to identify how to optimize and further implement a widely used group-based FPP in the Netherlands among participants, therapists and stakeholders using a mixed methods study. FPP participants and therapists filled out a questionnaire about their experiences with the FPP. Moreover, three focus groups were conducted with FPP participants, one with therapists and one with other stakeholders. Data were analysed according to the thematic analysis approach of Braun and Clarke. Overall, 93% of the 104 FPP participants were satisfied with the FPP and 86% (n = 12) of the therapists would recommend the FPP to older adults with balance or mobility difficulties. Moreover, six themes were identified regarding further implementation: (1) recruiting and motivating older adults to participate; (2) structure and content of the program; (3) awareness, confidence and physical effects; (4) training with peers; (5) funding and costs; and (6) long-term continuation. This study resulted in practical recommendations for optimizing and further implementing FPPs in practice.

New biomechanical models for cumulative plantar tissue stress assessment in people with diabetes at high risk of foot ulceration.

To better understand stress-related foot ulceration in diabetes, the cumulative plantar tissue stress (CPTS) should be quantified accurately, but also feasibly for clinical use. We developed multiple CPTS models with varying complexity and investigated their agreement with the most comprehensive reference model available. We assessed 52 participants with diabetes and high foot ulcer risk for barefoot and in-shoe plantar pressures during overground walking at different speeds, standing, sit-to-stand transitions, and stair walking. Level of these weight-bearing activities along with footwear adherence were objectively measured over seven days. The reference CPTS-model included the pressure-time integrals of each walking stride (barefoot and shod), specified for speed; standing period (barefoot and shod); transition and stair walking stride. We compared four CPTS-models with increasing number of input parameters (models 1-4) with the reference model, using repeated measures ANOVA, Pearson's correlation and Bland-Altman plots. For the clinically-relevant metatarsal 1 region, calculated CPTS was lower for the four CPTS-models compared to reference (Δ770, Δ466, Δ24 and Δ12 MPa.s/day, respectively). CPTS associated moderately with the reference model for model 1 (r = 0.551) and very strongly for models 2-4 (r ≥ 0.937). Limits of agreement were large for models 1 and 2 (-728;2269 and -302;1233 MPa.s/day), and small for models 3 and 4 (-43;92 and -54;78 MPa.s/day). CPTS in models 3 and 4 best agreed with the reference model, where model 3 required fewer parameters, i.e., pressure-time integrals of each walking stride and standing period while barefoot and shod. These parameters need to be included for accurate and feasible CPTS assessment.

Effects of Perturbation-Based Treadmill Training on Balance Performance, Daily Life Gait, and Falls in Older Adults: REACT Randomized Controlled Trial.

OBJECTIVE: The aim of this study was to evaluate the effect of perturbation-based treadmill training on gait quality in daily life, a predictor of fall risk that was used as the primary outcome. An additional aim was to evaluate the effects on secondary outcomes, including balance, gait performance, self-efficacy, daily life physical activity, and falls. METHODS: Seventy community-dwelling older adults (mean age = 74.73 [SD = 5.69] years; 46 women) at risk of falling were randomized and received 4 weeks of dual-task treadmill training, either with or without treadmill perturbations. Balance, gait performance, self-efficacy, and daily life trunk accelerometry at baseline, after intervention, and at a 6-month follow-up were assessed and compared within group over time and between groups for each time point, and their change rates between groups over time were also assessed. RESULTS: Both groups improved in their balance, gait performance, and self-efficacy; the experimental group showed a significantly larger decrease in concern of falling and an increase in physical performance than the controls. These training effects did not translate into significant improvements in daily life gait quality or physical activity. However, the number of daily life falls and the percentage of fallers decreased significantly more in the experimental group. CONCLUSION: A 4-week perturbation-based dual-task treadmill training program can improve self-efficacy, balance, and gait performance in a controlled setting and reduce daily life falls, although not through changes in quantity or quality of daily life gait. IMPACT: Perturbation-based treadmill training is a safe and efficient way to train older adults' balance recovery and gait performance, increase self-efficacy, and prevent falls.

In-shoe plantar pressure depends on walking speed and type of weight-bearing activity in people with diabetes at high risk of foot ulceration.

BACKGROUND: In evaluating therapeutic footwear, in-shoe plantar pressure is usually obtained during mid-gait steps at self-selected walking speed in a laboratory setting. However, this may not accurately represent plantar pressures or indicate the cumulative stress experienced in daily life. We investigated the effects of walking speed and different weight-bearing activities on in-shoe plantar pressure in people with diabetes at high risk of ulceration. METHODS: In a cross-sectional study including 30 participants we compared in-shoe plantar pressures between three standardized walking speeds (0.8, 0.6 and 0.4 m/s) and between walking at self-selected speed and eight other weight-bearing activities (3 components of the Timed Up and Go test, accelerating, decelerating, stair ascending and descending, and standing). Mean forefoot regional peak plantar pressure and pressure-time integral were statistically assessed per foot using linear mixed models (α < 0.05) with Holm-Bonferroni correction. FINDINGS: With increasing walking speed, peak pressures increased and pressure-time integrals decreased (P ≤ 0.014). Peak pressures during standing, decelerating, stair ascending and Timed Up and Go test were lower (P ≤ 0.001), and with other activities not different to walking at self-selected speed. Pressure-time integrals during stair ascending and descending were higher (P ≤ 0.001), during standing lower (P ≤ 0.009), and with other activities not different to walking at self-selected speed. INTERPRETATION: In-shoe plantar pressure depends on walking speed and type of weight-bearing activity. Only measuring pressures to evaluate footwear at self-selected walking speed in a laboratory setting may not accurately represent the stress on the foot in daily life of the high-risk patient; a more comprehensive assessment is suggested.

Towards a core-set of mobility measures in ageing research: The need to define mobility and its constructs.

BACKGROUND: Mobility is a key determinant and outcome of healthy ageing but its definition, conceptual framework and underlying constructs within the physical domain may need clarification for data comparison and sharing in ageing research. This study aimed to (1) review definitions and conceptual frameworks of mobility, (2) explore agreement on the definition of mobility, conceptual frameworks, constructs and measures of mobility, and (3) define, classify and identify constructs. METHODS: A three-step approach was adopted: a literature review and two rounds of expert questionnaires (n = 64, n = 31, respectively). Agreement on statements was assessed using a five-point Likert scale; the answer options 'strongly agree' or 'agree' were combined. The percentage of respondents was subsequently used to classify agreements for each statement as: strong (≥ 80%), moderate (≥ 70% and < 80%) and low (< 70%). RESULTS: A variety of definitions of mobility, conceptual frameworks and constructs were found in the literature and among respondents. Strong agreement was found on defining mobility as the ability to move, including the use of assistive devices. Multiple constructs and measures were identified, but low agreements and variability were found on definitions, classifications and identification of constructs. Strong agreements were found on defining physical capacity (what a person is maximally capable of, 'can do') and performance (what a person actually does in their daily life, 'do') as key constructs of mobility. CONCLUSION: Agreements on definitions of mobility, physical capacity and performance were found, but constructs of mobility need to be further identified, defined and classified appropriately. Clear terminology and definitions are essential to facilitate communication and interpretation in operationalising the physical domain of mobility as a prerequisite for standardisation of mobility measures.

Physical activity levels in cognitively normal and cognitively impaired oldest-old and the association with dementia risk factors: a pilot study.

BACKGROUND: Research assessing the relationship of physical activity and dementia is usually based on studies with individuals younger than 90 years of age. The primary aim of this study was to determine physical activity levels of cognitively normal and cognitively impaired adults older than 90 years of age (oldest-old). Our secondary aim was to assess if physical activity is associated with risk factors for dementia and brain pathology biomarkers. METHODS: Physical activity was assessed in cognitively normal (N = 49) and cognitively impaired (N = 12) oldest-old by trunk accelerometry for a 7-day period. We tested physical performance parameters and nutritional status as dementia risk factors, and brain pathology biomarkers. Linear regression models were used to examine the associations, correcting for age, sex and years of education. RESULTS: Cognitively normal oldest-old were on average active for a total duration of 45 (SD 27) minutes per day, while cognitively impaired oldest-old seemed less physically active with 33 (SD 21) minutes per day with a lower movement intensity. Higher active duration and lower sedentary duration were related to better nutritional status and better physical performance. Higher movement intensities were related to better nutritional status, better physical performance and less white matter hyperintensities. Longer maximum walking bout duration associated with more amyloid binding. CONCLUSION: We found that cognitively impaired oldest-old are active at a lower movement intensity than cognitively normal oldest-old individuals. In the oldest-old, physical activity is related to physical parameters, nutritional status, and moderately to brain pathology biomarkers.

Patterns of Objectively Measured Sedentary Behavior and Physical Activity and Their Association with Changes in Physical and Functional Performance in Geriatric Rehabilitation Inpatients.

OBJECTIVES: To examine whether The Ending PyJama (PJ) Paralysis campaign, focused on increasing in-hospital physical activity, affects objectively measured sedentary behavior and physical activity patterns and if these are associated with changes in physical and functional performance in geriatric rehabilitation inpatients. DESIGN: Quasi-experimental study. SETTING AND PARTICIPANTS: Within the REStORing health of acutely unwell adulTs (RESORT) observational, longitudinal cohort of geriatric rehabilitation inpatients, the Ending PJ Paralysis campaign was implemented on 2 out of 4 wards. METHODS: Objectively measured sedentary behavior and physical activity were measured by an inertial sensor (ActivPAL4) for 1 week, comparing control (non-PJ) and intervention (PJ) groups using linear mixed models. Mean sedentary behavior and physical activity measures and their association with physical and functional performance changes were investigated by linear regression analyses, stratified by low vs high performance at admission using the median as a cut-off. RESULTS: A total of 145 (n = 68 non-PJ and n = 77 PJ) inpatients with a mean age of 83.0 (7.7) years (55.9% female inpatients) were included. The median nonupright time was 23.1 [22.1-23.6] and 23.0 [21.8-23.6] hours/day for non-PJ and PJ groups, respectively. Objectively measured sedentary behavior and physical activity measures did not significantly change over measurement days and were independent of the Ending PJ Paralysis campaign. For inpatients with low performance at admission, lower sedentary behavior [B(SE) -0.013 (0.005) to -0.157 (0.045), P < .01] and higher physical activity [B(SE) 0.033 (0.007) to 0.814 (0.200), P < .01] measures were associated with improved physical performance. In addition, lower sedentary behaviour [B(SE) = -0.058 (0.024), P < .05 and higher physical activity [B (SE) 0.060 (0.024) to 0.683 (0.182), P < .05] were associated with improved instrumental functional performance. CONCLUSIONS AND IMPLICATIONS: In geriatric rehabilitation inpatients, the Ending PJ Paralysis campaign did not affect objectively measured sedentary behavior and physical activity patterns. Lower mean sedentary behaviour and higher physical activity measures were associated with improved physical and functional performance in inpatients with low performance.

A formula for calculating 30-item Geriatric Depression Scale (GDS-30) scores from the 15-item version (GDS-15).

The Geriatric Depression Scale with 30 items (GDS-30) and with 15 items (GDS-15) are both valid tools for assessing depression in older adults, but their absolute values are not directly comparable. Here, we used a dataset (n = 431) with GDS-30 scores from a project concerning fall-risk assessment in older adults (FARAO) to develop and validate a formula which can be used to convert GDS-15 scores into GDS-30 scores. We found that the GDS-15 score cannot simply be multiplied by 2 to obtain the GDS-30 scores and that estimations of GDS-30 from GDS-15 are not affected by age, sex and MMSE. Therefore, the optimal formula to estimate the GDS-30 score from the GDS-15 score was: GDS-30_estimated = 1.57 + 1.95 × GDS-15. This formula yielded an estimate of GDS-30 with an explained variance of 79 %, compared to 63 % when GDS-15 was simply multiplied by 2. Researchers that have used the GDS-15 and want to compare their outcomes to other studies that reported only the GDS-30 are advised to use this formula.

Impact of adherence to a lifestyle-integrated programme on physical function and behavioural complexity in young older adults at risk of functional decline: a multicentre RCT secondary analysis.

CONTEXT: Long-term adherence to physical activity (PA) interventions is challenging. The Lifestyle-integrated Functional Exercise programmes were adapted Lifestyle-integrated Functional Exercise (aLiFE) to include more challenging activities and a behavioural change framework, and then enhanced Lifestyle-integrated Functional Exercise (eLiFE) to be delivered using smartphones and smartwatches. OBJECTIVES: To (1) compare adherence measures, (2) identify determinants of adherence and (3) assess the impact on outcome measures of a lifestyle-integrated programme. DESIGN, SETTING AND PARTICIPANTS: A multicentre, feasibility randomised controlled trial including participants aged 61-70 years conducted in three European cities. INTERVENTIONS: Six-month trainer-supported aLiFE or eLiFE compared with a control group, which received written PA advice. OUTCOME MEASURES: Self-reporting adherence per month using a single question and after 6-month intervention using the Exercise Adherence Rating Scale (EARS, score range 6-24). Treatment outcomes included function and disability scores (measured using the Late-Life Function and Disability Index) and sensor-derived physical behaviour complexity measure. Determinants of adherence (EARS score) were identified using linear multivariate analysis. Linear regression estimated the association of adherence on treatment outcome. RESULTS: We included 120 participants randomised to the intervention groups (aLiFE/eLiFE) (66.3±2.3 years, 53% women). The 106 participants reassessed after 6 months had a mean EARS score of 16.0±5.1. Better adherence was associated with lower number of medications taken, lower depression and lower risk of functional decline. We estimated adherence to significantly increase basic lower extremity function by 1.3 points (p<0.0001), advanced lower extremity function by 1.0 point (p<0.0001) and behavioural complexity by 0.008 per 1.0 point higher EARS score (F(3,91)=3.55, p=0.017) regardless of group allocation. CONCLUSION: PA adherence was associated with better lower extremity function and physical behavioural complexity. Barriers to adherence should be addressed preintervention to enhance intervention efficacy. Further research is needed to unravel the impact of behaviour change techniques embedded into technology-delivered activity interventions on adherence. TRIAL REGISTRATION NUMBER: NCT03065088.

Physical activity as a risk or protective factor for falls and fall-related fractures in non-frail and frail older adults: a longitudinal study.

BACKGROUND: Physical activity may be both a risk and protective factor for falls and fall-related fractures. Despite its positive effects on muscle and bone health, physical activity also increases exposure to situations where falls and fractures occur. This paradox could possibly be explained by frailty status. Therefore, the aim of this study was to investigate the associations between physical activity and both falls and fractures, and to determine whether frailty modifies the association of physical activity with falls, and fractures. METHODS: Data of 311 community-dwelling participants aged 75 years or older from the Longitudinal Aging Study Amsterdam, who participated in a three-year longitudinal study with five nine-monthly measurements between 2015/2016 and 2018/2019. Their mean age was 81.1 (SD 4.8) years and frailty was present in 30.9% of the participants. Physical activity in minutes per day was objectively assessed with an inertial sensor (Actigraph) for seven consecutive days. Falls and fractures were assessed every nine months using self-report during an interview over a follow-up period of three years. Frailty was determined at baseline using the frailty index. Associations were estimated using longitudinal logistic regression analyses based on generalized estimating equations. RESULTS: No association between physical activity and falls was found (OR = 1.00, 95% CI: 0.99-1.00). Fall risk was higher in frail compared to non-frail adults (OR = 2.21, 95% CI: 1.33-3.68), but no effect modification was seen of frailty on the association between physical activity and falls. Also no relation between physical activity and fractures was found (OR = 1.00, 95% CI: 0.99-1.01). Fracture risk was higher in frail compared to non-frail adults (OR = 2.81, 95% CI: 1.02-7.75), but also no effect modification of frailty was present in the association between physical activity and fractures. CONCLUSIONS: No association between physical activity and neither falls nor fractures was found, and frailty appeared not to be an effect modifier. However, frailty was a risk factor for falls and fractures in this population of older adults. Our findings suggest that physical activity can be safely recommended in non-frail and frail populations for general health benefits, without increasing the risk of falls.

Albumin and C-reactive protein relate to functional and body composition parameters in patients admitted to geriatric rehabilitation after acute hospitalization: findings from the RESORT cohort.

PURPOSE: Albumin and C-reactive protein (CRP) are non-specific markers of inflammation, which could affect muscle tissue during acute hospitalization. We investigated the association between albumin and CRP during acute hospitalization with functional and body composition parameters in patients admitted to geriatric rehabilitation. METHODS: The REStORing Health of Acutely Unwell AdulTs (RESORT) cohort includes geriatric rehabilitation patients assessed for change in activities of daily living (ADL, using the Katz index) during acute hospitalization, and subsequently for Katz ADL, gait speed (GS), handgrip strength (HGS) and skeletal muscle mass index (SMI) at geriatric rehabilitation admission. Albumin and CRP average (median), variation (interquartile range), and maximum or minimum were collected from serum samples, and were examined for their association with functional and body composition parameters using multivariable linear regression analysis adjusted for age, sex and length of acute hospital stay. RESULTS: 1769 Inpatients were included for analyses (mean age 82.6 years ± 8.1, 56% female). Median length of acute hospitalization was 7 [IQR 4, 13] days and median number of albumin and CRP measurements was 5 [IQR 3, 12] times. ADL declined in 89% of patients (median - 3 points, IQR - 4, - 2). Lower average albumin, higher albumin variation and lower minimum albumin were associated with larger declines in ADL and with lower ADL, GS, HGS and SMI at geriatric rehabilitation admission. Higher average and maximum CRP were associated with lower GS. CONCLUSION: Inflammation, especially lower albumin concentrations, during acute hospitalization is associated with lower physical function at geriatric rehabilitation admission.

Contribution of arm movements to balance recovery after tripping in older adults.

Falls are common in daily life, often caused by trips and slips and, particularly in older adults, with serious consequences. Although arm movements play an important role in balance control, there is limited research into the role of arm movements during balance recovery after tripping in older adults. We investigated how older adults use their arms to recover from a trip and the difference in the effects of arm movements between fallers (n = 5) and non-fallers (n = 11). Sixteen older males and females (69.7 ± 2.3 years) walked along a walkway and were occasionally tripped over suddenly appearing obstacles. We analysed the first trip using a biomechanical model based on full-body kinematics and force-plate data to calculate whole body orientation during the trip and recovery phase. With this model, we simulated the effects of arm movements at foot-obstacle impact and during trip recovery on body orientation. Apart from an increase in sagittal plane forward body rotation at touchdown in fallers, we found no significant differences between fallers and non-fallers in the effects of arm movements on trip recovery. Like earlier studies in young adults, we found that arm movements during the recovery phase had most favourable effects in the transverse plane: by delaying the transfer of angular momentum of the arms to the body, older adults rotated the tripped side more forward thereby allowing for a larger recovery step. Older adults that are prone to falling might improve their balance recovery after tripping by learning to prolong ongoing arm movements.

Responsiveness of Daily Life Gait Quality Characteristics over One Year in Older Adults Who Experienced a Fall or Engaged in Balance Exercise.

Gait quality characteristics obtained from daily-life accelerometry are clinically relevant for fall risk in older adults but it is unknown whether these characteristics are responsive to changes in gait quality. We aimed to test whether accelerometry-based daily-life gait quality characteristics are reliable and responsive to changes over one year in older adults who experienced a fall or an exercise intervention. One-week trunk acceleration data were collected from 522 participants (65-97 years), at baseline and after one year. We calculated median values of walking speed, regularity (sample entropy), stability (logarithmic rate of divergence per stride), and a gait quality composite score, across all 10-s gait epochs derived from one-week gait episodes. Intraclass correlation coefficients (ICC) and limits of agreement (LOA) were determined for 198 participants who did not fall nor participated in an exercise intervention during follow-up. For responsiveness to change, we determined the number of participants who fell (n = 209) or participated in an exercise intervention (n = 115) that showed a change beyond the LOA. ICCs for agreement between baseline and follow-up exceeded 0.70 for all gait quality characteristics except for vertical gait stability (ICC = 0.69, 95% CI [0.62, 0.75]) and walking speed (ICC = 0.68, 95% CI [0.62, 0.74]). Only walking speed, vertical and mediolateral gait stability changed significantly in the exercisers over one year but effect sizes were below 0.2. The characteristic associated with most fallers beyond the LOA was mediolateral sample entropy (4.8% of fallers). For the exercisers, this was gait stability in three directions and the gait quality composite score (2.6% of exercisers). The gait quality characteristics obtained by median values over one week of trunk accelerometry were not responsive to presumed changes in gait quality after a fall or an exercise intervention in older people. This is likely due to large (within subjects) differences in gait behaviour that participants show in daily life.

Patients' perceived walking abilities, daily-life gait behavior and gait quality before and 3 months after total knee arthroplasty.

INTRODUCTION: Functional outcome and patients' daily-life activities after total knee arthroplasty are becoming more important with a younger and more active patient population. In addition to patient-reported outcome measures (PROMs), trunk-based accelerometry has shown to be a promising method for evaluating gait function after total knee arthroplasty. The aim of this study was to evaluate daily-life perceived walking abilities, gait behavior and gait quality before and 3 months after total knee arthroplasty, using PROMs and trunk-based accelerometry. MATERIALS AND METHODS: A cohort of 38 patients completed questionnaires including the Oxford Knee Score and modified Gait Efficacy Scale before and 3 months after primary unilateral total knee arthroplasty. At both time points, they wore a tri-axial accelerometer at the lower back for seven consecutive days and nights. Gait behavior was calculated using gait quantity and walking speed, and multiple gait quality parameters were calculated. RESULTS: Significant improvements were seen after 3 months in the Oxford Knee Score [median (interquartile range) 29 (10) vs 39 (8), p < 0.001] and modified Gait Efficacy Scale [median (interquartile range) 67 (24) vs 79 (25), p = 0.001]. No significant changes were observed in gait behavior (quantity and speed) or gait quality variables. CONCLUSIONS: In contrast to the significant improvements in patients' perception of their walking abilities and PROMs, patients did not show improvements in gait behavior and gait quality. This implies that after 3 months patients' perceived functional abilities after total knee arthroplasty do not necessarily represent their actual daily-life quantity and quality of gait, and that more focus is needed on postoperative rehabilitation to improve gait and functional behavior.

Rapid Inhibition Accuracy and Leg Strength Are Required for Community-Dwelling Older People to Recover Balance From Induced Trips and Slips: An Experimental Prospective Study.

BACKGROUND AND PURPOSE: Falls can result in bone fractures and disability, presenting a serious threat to quality of life and independence in older adults. The majority of falls in community-living older adults occur while walking and are often caused by trips and slips. The study aimed to identify the specific sensorimotor and psychological factors required for older adults to recover balance from trips and slips. METHODS: Forty-one older adults aged 65 to 87 years were assessed on sensorimotor (knee extension strength, proprioception, postural sway, and edge contrast sensitivity), reaction (simple reaction time, stepping, and catching reaction inhibition), and psychological (general anxiety and concern about falling) measures. Using a harness system, participants walked at 90% of their usual pace on a 10-m walkway that could induce trips and slips in concealed and changeable locations. Post-perturbation responses resulting in more than 30% of body weight being recorded by the harness system were defined as falls. Poisson regressions were used to test associations between the sensorimotor, reaction, and psychological measures and number of falls. RESULTS: Fifty-one falls occurred in 25 of 41 participants. Poisson regression revealed body mass index, lower-limb proprioception, knee extension strength, rapid inhibition accuracy, concern about falling, and anxiety were significantly associated with the rate of falls. Other measures including postural sway were not statistically significant. Using stepwise Poisson regression analyses, normalized knee extension strength (rate ratio [RR]: 0.68, 95% confidence interval [CI]: 0.47-0.98), and rapid inhibition accuracy (RR: 0.64, 95% CI: 0.46-0.87) were independently associated with falls. CONCLUSION: Our findings suggest rapid inhibition accuracy and adequate leg strength are required for older adults to recover balance from trips and slips. The mechanisms for balance recovery during daily life activities are likely different from those for static balance, suggesting the need for task-specific assessments and interventions for fall prevention in older adults.

Determinants of instrumented sedentary and physical activity behavior in geriatric rehabilitation inpatients: RESORT.

BACKGROUND: Physical inactivity in hospitalized older adults is highly prevalent and associated with detrimental health outcomes. Understanding its determinants is important for prognosis and tailoring interventions in geriatric rehabilitation inpatients. METHODS: Within the REStORing health of acutely unwell adulTs (RESORT) observational, longitudinal cohort, geriatric rehabilitation inpatients wore an inertial sensor (ActivPAL4) for one week to objectively assess instrumented sedentary behavior (i-SB) and physical activity (i-PA). Determinants were grouped in five geriatric domains: morbidity, cognition/psychology, physical performance, functional performance, and nutritional status. Their association with i-SB (mean sitting, lying, non-upright time) and i-PA (mean number of steps, sit-to-stand transitions and upright time) quintiles were examined using multivariate ordinal logistic regression analyses with Bonferroni correction (p < 0.006). RESULTS: A total of 145 inpatients were included (mean age 83.0, SD 7.7 years; 55.9% females). More comorbidities were associated with a lower daily number of steps (OR:0.91, 95%CI: 0.86-0.96) and lower upright time (OR:0.93, 95%CI: 0.88-0.98). Depressive symptoms (higher Hospital Anxiety and Depression Scale score) were associated with higher non-upright time (OR: 1.12, 95%CI: 1.03-1.21) and lower upright time (OR: 0.89, 95%CI: 0.83-0.96). Better physical performance (higher Functional Ambulation Classification, gait speed, and Short Physical Performance Battery score) was associated with lower i-SB measures (OR range: 0.07-0.78, p < 0.0005) and higher i-PA measures (OR range: 1.35-19.50, p < 0.0005). Higher functional performance (Katz index of Activities of Daily Living score) was associated with lower i-SB measures (OR range: 0.61-0.69, p ≤ 0.003) and higher i-PA measures (OR range: 1.60-3.64, p < 0.0005). Being malnourished was associated with lower i-PA measures (OR range: 0.29-0.32, p ≤ 0.004). CONCLUSIONS: Worse morbidity, depressive symptoms, worse physical and functional performance, and worse nutritional status were associated with higher i-SB and lower i-PA. These determinants should be taken into account while designing and promoting multidisciplinary physical activity interventions.

The short- and long-term temporal relation between falls and concern about falling in older adults without a recent history of falling.

BACKGROUND AND AIM: The reciprocal relation between falling and concern about falling is complex and not well understood. We aimed to determine whether concern about falling increases after a fall and whether concern about falling increases the odds of future falls in community-dwelling older adults without a recent fall history. METHODS: We selected 118 community-dwelling older adults (mean age: 71.4 (SD: 5.3) years) without a self-reported history of falling, one year prior to baseline assessment, from the one-year VIBE cohort for analyses. On a monthly basis, we recorded concern about falling (using the Falls Efficacy Scale-International, FES-I), as well as the occurrence of falls (through questionnaires and telephone calls). We determined 1) whether falling predicts an increase in concern about falling and 2) whether a high concern about falling is predictive of falling. Standard linear (fixed-effects) regression and mixed effects regression analyses were performed over long-term, i.e. one year, and short-term, i.e. one-month, intervals, respectively and were adjusted for gender, age and physical activity (quantified as the average total walking duration per day). Analyses were performed separately for all reported falls and for injurious falls only. RESULTS: High concern about falling at baseline did not predict falls over the course of one year, nor over the course of one month. Furthermore, falls in between baseline assessment and one year thereafter did not predict increased concern about falling from baseline to one year later, independent of whether all falls or only injurious falls were considered. However, falls, either all or injurious only, happening somewhere over the course of a one-month interval, significantly predicted small increases in concern about falling (1.49 FES-I points, 95% CI [0.74, 2.25], p<0.001 for all falls; 2.60 FES-I points, 95% CI [1.55, 3.64], p<0.001 for injurious falls) from the start to the end of that one-month interval. CONCLUSION: Older adults without a recent history of falling seem to be resilient against developing concern about falling after having fallen, resulting in a short-term temporary effect of falling on concern about falling. Furthermore, we found no evidence that a high concern about falling predicts future falls over a one-month or a one-year follow-up period, suggesting that concern is not a primary cause for falls in older adults without a recent history of falling.

The (cost-)effectiveness of an implemented fall prevention intervention on falls and fall-related injuries among community-dwelling older adults with an increased risk of falls: protocol for the in balance randomized controlled trial.

BACKGROUND: Falls and fall-related injuries among older adults are a serious threat to the quality of life and result in high healthcare and societal costs. Despite evidence that falls can be prevented by fall prevention programmes, practical barriers may challenge the implementation of these programmes. In this study, we will investigate the effectiveness and cost-effectiveness of In Balance, a fourteen-week, low-cost group fall prevention intervention, that is widely implemented in community-dwelling older adults with an increased fall risk in the Netherlands. Moreover, we will be the first to include cost-effectiveness for this intervention. Based on previous evidence of the In Balance intervention in pre-frail older adults, we expect this intervention to be (cost-)effective after implementation-related adjustments on the target population and duration of the intervention. METHODS: This study is a single-blinded, multicenter randomized controlled trial. The target sample will consist of 256 community-dwelling non-frail and pre-frail adults of 65 years or older with an increased risk of falls. The intervention group receives the In Balance intervention as it is currently widely implemented in Dutch healthcare, which includes an educational component and physical exercises. The physical exercises are based on Tai Chi principles and focus on balance and strength. The control group receives general written physical activity recommendations. Primary outcomes are the number of falls and fall-related injuries over 12 months follow-up. Secondary outcomes consist of physical performance measures, physical activity, confidence, health status, quality of life, process evaluation and societal costs. Mixed model analyses will be conducted for both primary and secondary outcomes and will be stratified for non-frail and pre-frail adults. DISCUSSION: This trial will provide insight into the clinical and societal impact of an implemented Dutch fall prevention intervention and will have major benefits for older adults, society and health insurance companies. In addition, results of this study will inform healthcare professionals and policy makers about timely and (cost-)effective prevention of falls in older adults. TRIAL REGISTRATION: Netherlands Trial Register: NL9248 (registered February 13, 2021).