Clustering Approaches for Gait Analysis within Neurological Disorders: A Narrative Review.

Background: The prevalence of neurological disorders is increasing, underscoring the importance of objective gait analysis to help clinicians identify specific deficits. Nevertheless, existing technological solutions for gait analysis often suffer from impracticality in daily clinical use, including excessive cost, time constraints, and limited processing capabilities. Summary: This review aims to evaluate existing techniques for clustering patients with the same neurological disorder to assist clinicians in optimizing treatment options. A narrative review of thirteen relevant studies was conducted, characterizing their methods, and evaluating them against seven criteria. Additionally, the results are summarized in two comprehensive tables. Recent approaches show promise; however, our results indicate that, overall, only three approaches display medium or high process maturity, and only two show high clinical applicability. Key Messages: Our findings highlight the necessity for advancements, specifically regarding the use of markerless optical tracking systems, the optimization of experimental plans, and the external validation of results. This narrative review provides a comprehensive overview of existing clustering techniques, bridging the gap between instrumented gait analysis and its real-world clinical utility. We encourage researchers to use our findings and those from other medical fields to enhance clustering techniques for patients with neurological disorders, facilitating the identification of disparities within groups and their extent, ultimately improving patient outcomes.

Acceptability of Two Perturbation-based Balance Training Paradigms: Perturbation Treadmill vs Dynamic Stability Training in the Presence of Perturbations.

INTRODUCTION: Perturbation-based balance training is promising for fall prevention in older adults mimicking real-life fall situations at a person's stability thresholds to improve reactive balance. Hence, it can be associated with anxiety, but knowledge about the acceptability of perturbation-based balance training is scarce. METHOD: This is a secondary analysis of a randomized controlled trial comparing effects of two different perturbation-based balance training paradigms that aims to evaluate and compare the acceptability of those training paradigms in fall-prone older adults. Participants (74.9±5.7 years) who completed the training (6 weeks, 3x/week) on either a perturbation treadmill (PBTtreadmill: n=22) or unstable surfaces in the presence of perturbations (PBTstability: n=27) were surveyed on the acceptability of perturbation-based balance training using a 21-items questionnaire addressing seven domains (perceived effectiveness, tailoring, demand, safety, burden, devices, affective attitude), based on the Theoretical Framework of Acceptability and context-specific factors. Relative scores (% of absolute maximum) for single items and domains were calculated. RESULTS: Median domain scores of perceived effectiveness, tailoring, safety, devices, and affective attitude were all ≥70% for both paradigms. The highest scores were obtained for tailoring (both paradigms=100% [interquartile range 80-100%]). Domain scores of demand and burden were in the medium range (40-45%) for both paradigms. No significant differences between paradigms were found for any domain score. Two single items of safety differed significantly, with PBTtreadmill perceived as needing less support (p=.015) and leading less often to balance loss (p=.026) than PBTstability. CONCLUSION: Perturbation-based balance training conducted on a perturbation treadmill or on unstable surfaces is well accepted in this fall-prone older sample, even though it is conducted at individual stability thresholds. Tailoring may play a key role in achieving high levels of perceived effectiveness, appropriate levels of demand and burden, and high sense of safety. Perturbation-based balance training delivered on treadmills might be more appropriate for more anxious persons.

Spatiotemporal modulation of a common set of muscle synergies during unpredictable and predictable gait perturbations in older adults.

Muscle synergies as functional low-dimensional building blocks of the neuromotor system regulate the activation patterns of muscle groups in a modular structure during locomotion. The purpose of the current study was to explore how older adults organize locomotor muscle synergies to counteract unpredictable and predictable gait perturbations during the perturbed steps and the recovery steps. Sixty-three healthy older adults (71.2±5.2 years) participated in the study. Mediolateral and anteroposterior unpredictable and predictable perturbations during walking were introduced using a treadmill. Muscle synergies were extracted from the electromyographic activity of 13 lower limb muscles using Gaussian non-negative matrix factorization. The four basic synergies responsible for unperturbed walking (weight acceptance, propulsion, early swing and late swing) were preserved in all applied gait perturbations, yet their temporal recruitment and muscle contribution in each synergy were modified (P<0.05). These modifications were observed for up to four recovery steps and were more pronounced (P<0.05) following unpredictable perturbations. The recruitment of the four basic walking synergies in the perturbed and recovery gait cycles indicates a robust neuromotor control of locomotion by using activation patterns of a few and well-known muscle synergies with specific adjustments within the synergies. The selection of pre-existing muscle synergies while adjusting the time of their recruitment during challenging locomotor conditions may improve the effectiveness to deal with perturbations and promote the transfer of adaptation between different kinds of perturbations.

Budget impact analysis of a Lifestyle-integrated Functional Exercise (LiFE) program for older people in Germany: a Markov model based on data from the LiFE-is-LiFE trial.

BACKGROUND: Fall prevention is important for healthy ageing, but the economic impact of fall prevention are scarcely investigated. A recent cost-effectiveness analysis compared a group-delivered Lifestyle-integrated Functional Exercise Program (gLiFE) with an individually-delivered program (LiFE) in community-dwelling people (aged ≥ 70 years) at risk of falling. In addition, the current study aimed to analyze the budget impact of LiFE and gLiFE, compared with standard care in Germany. METHODS: A Markov model was developed to reflect falls and associated care needs for community-dwelling persons over 5 years. The intervention effects of LiFE and gLiFE were shown to be equivalent in a non-inferiority trial, although the costs differed. Outpatient, inpatient, and intervention costs were assessed from a payer's perspective. The effect of parameter uncertainty was assessed in sensitivity analyses. RESULTS: The budget impact due to intervention costs was €510 million for LiFE and €186 million for gLiFE. Over five years, health care expenditures were €35,008 million for those receiving standard care, €35,416 million for those receiving LiFE, and €35,091 million for persons receiving gLiFE. Thereby, LiFE and gLiFE could prevent 2700 deaths and 648,000 falls over 5 years. Parameter uncertainties in the risk of falling, uptake of an intervention offer, and in the intervention effects had a major influence; thus cost savings for LiFE and gLiFE compared with standard care could be achieved for individuals with a high risk of falling. CONCLUSIONS: The results revealed that cost savings for LiFE and gLiFE compared with standard care could only be achieved for individuals at high risk of falling, with gLiFE being superior to LiFE. Future research should consider benefits and aspects of fall prevention beyond falls (e.g., physical activity, social aspects, and personal preferences of participants). TRIAL REGISTRATION: The study was preregistered under underclinicaltrials.gov (identifier: NCT03462654) on 12th March 2018; https://clinicaltrials.gov/ct2/show/NCT03462654 .

Estimation of Average and Maximum Daily-Life Mobility Performance Using the Timed Up-and-Go: Exploring the Added Value of an Instrumented Timed Up-and-Go.

INTRODUCTION: The association between specific motor capacity variables obtained in a laboratory and parameters of daily-life mobility performance (MP) obtained via wearables is still unclear. The Timed Up-and-Go (TUG) test is a widely used motor capacity tests available either as traditional hand-stopped TUG or as instrumented TUG (iTUG), providing specific information about its subphases. This study aimed to: (1) estimate the association between the TUG and specific parameters reflecting average and maximum daily-life MP, (2) estimate the benefits of the iTUG in terms of explaining MP in daily life compared to the TUG. METHODS: The present study was a cross-sectional analysis using baseline data of 294 older persons (mean age: 76.7 ± 5.3 years). Univariate linear regression analysis was performed to delineate the coefficient of determination between TUG time and participants' MP. MP variables containing mean cadence (MCA) to represent average performance and the 95th percentile of mean cadence of walks with more than three steps (p95>3stepsMCA) to represent maximum performance. To determine whether the iTUG variables give more information about MP, a stepwise multivariate regression analysis between iTUG variables and the p95>3stepsMCA variable to represent maximum performance was conducted. RESULTS: The univariate regression models revealed associations of the TUG with MCA (adjusted R2 = 0.078, p < 0.001) and p95>3stepsMCA (adjusted R2 = 0.199, p < 0.001). The multivariate stepwise regression models revealed a total explanation of maximum daily-life MP (p95>3stepsMCA) of the TUG (adjusted R2 = 0.199, p < 0.001) versus iTUG (adjusted R2 = 0.278, p < 0.010). DISCUSSION/CONCLUSION: This study shows that the TUG better reflects maximum daily-life MP than average daily-life MP. Moreover, we demonstrate the added value of the iTUG for a more accurate estimation of daily MP compared to the traditional TUG. The iTUG is recommended to estimate maximum daily-life MP in fall-prone older adults. The study is a step toward a specific assessment paradigm using capacity variables from the iTUG to estimate maximum daily-life MP.

[Update of the recommendations of the Federal Falls Prevention Initiative-Identification and prevention of the risk of falling in older people living at home]. / Update der Empfehlungen der Bundesinitiative Sturzprävention ­ Identifizierung und Prävention des Sturzrisikos bei älteren zu Hause lebenden Menschen.

BACKGROUND: To reduce falls and their consequences, evidence-based and consensus-based recommendations are needed for risk stratification, screening, assessment, and fall prevention as well as treatment. In 2020, the Federal Falls Prevention Initiative (BIS) published recommendations for physical training for falls prevention as a group or individual intervention for older people living at home. In 2022, the world guidelines for falls prevention and management for older adults (WFG) were published. OBJECTIVE: To update the recommendations of the BIS. MATERIAL AND METHODS: The recommendations of the BIS were compared with those of the WFG and, if necessary, extended by methodological and subject-specific aspects. The following areas were considered: 1) screening and risk stratification, 2) interventions, 3) multifactorial assessment and interventions, and 4) specific target groups. RESULTS: The BIS recommendations are largely consistent with those of the WFG. The main reason for differences is the previous focus of the BIS recommendations on physical training. The multifactorial approach, which is described in detail by the WFG, has so far been mentioned in the recommendation paper on physical training in individual settings but not elaborated in detail. The BIS recommendations are supplemented or clarified in this respect. CONCLUSION: By updating the BIS recommendations, the establishment and promotion of fall prevention services for older people in Germany can be further advanced. The implementation can thus be carried out as consistently and scientifically proven as possible.

[Lifestyle-integrated functional exercise for fall prevention : How and why do walking characteristics change?] / Lebensstilintegriertes funktionelles Training zur Sturzprävention : Wie und warum verändert sich das Gehverhalten?

BACKGROUND: The lifestyle-integrated functional exercise (LiFE) program has been shown to increase physical activity. It remains unclear, however, how these changes translate into long vs. short walking episodes. OBJECTIVE: The aim of this work was to investigate changes in short vs. long walking episodes between baseline and 6­month follow-up and to determine which factors are associated with these changes. MATERIAL AND METHODS: This was a two-arm randomized noninferiority study with 309 older adults (mean age 78.7 ± 0.3 years; 73.5% female) at risk of falling who exercised either in a group (gLiFE; n = 153) or individually (LiFE; n = 156). Walking episodes were measured using activPAL 4micro sensors: a distinction was made between walking episodes < 10s, < 20s, and > 60 s. Changes in walking episodes between baseline and 6­month follow-up were analyzed, including calculation of effect sizes (Cohen's d). Determinants of changes in the walking episodes were analyzed using multiple regression. RESULTS: The walking episodes < 10s and < 20 s showed a significant increase in both intervention groups but not for > 60 s. The overall daily walking duration and average steps per day had an influence on changes in the walking episodes between baseline and 6 months. Parameters of objective and subjective function explained a very small but significant amount of the variance. CONCLUSION: The LiFE program seems to work on a behavioral rather than on a functional level. By accumulating short walking episodes, large gains in physical activity can potentially be achieved. This can be of health-promoting benefit especially for persons living in institutional settings or for those who are cautious or even anxious to undertake longer walking episodes (e.g., outdoors).

Effects of Physical Activity Interventions on Strength, Balance and Falls in Middle-Aged Adults: A Systematic Review and Meta-Analysis.

BACKGROUND: Weak lower body strength and balance impairments are fundamental risk factors for mobility impairments and falls that can be improved by physical activity (PA). Previous meta-analyses have focused on these risk factors in adults aged ≥ 65 years. Yet, the potential of PA for improving these risk factors in middle-aged populations has not been systematically investigated. This systematic review and meta-analysis aim to examine the effect of general and structured PA on lower limb strength, postural balance and falls in middle-aged adults. METHODS: A computerized systematic literature search was conducted in the electronic databases MEDLINE, CINAHL, Web of Science and Cochrane Library. PA intervention types were classified according to the ProFaNE taxonomy. Randomized controlled trials exploring the effects of PA on strength (e.g., leg press one-repetition-maximum), balance (e.g., single limb stance) and falls (e.g., fall rates) in adults aged 40-60 years were systematically searched and included in a network analysis. Moderator analyses were performed for specific subgroups (age, sex, low PA). The methodological quality of the included studies was assessed using the Physiotherapy Evidence Database (PEDro) Scale. RESULTS: Out of 7170 articles screened, 66 studies (median PEDro score 5) with 3387 participants were included. Strong, significant effects on muscle strength were found for strength (SMD = 1.02), strength-aerobic (SMD = 1.41), strength-endurance (SMD = 0.92) and water-based (SMD = 1.08) training (52 studies, I2 = 79.3%). Strength training (SMD = 1.16), strength-aerobic (SMD = 0.98) and 3D training (SMD = 1.31) improved postural balance (30 studies, I2 = 88.1%). Moderator analyses revealed significant effects of specific intervention types on certain subgroups and subdomains of strength and balance. No studies were found measuring falls. CONCLUSIONS: Structured PA interventions in middle-aged adults improve strength and balance outcomes related to functional impairments and falls. Strength training increases both strength and balance and can be recommended to prevent age-related functional decline. However, the interpretability of the results is limited due to considerable heterogeneity and the overall low methodological quality of the included studies. Long-term trials are needed to determine the preventive potential of PA on strength, balance and falls. This meta-analysis may inform guidelines for tailored training during middle age to promote healthy aging. Prospero registration: CRD42020218643.

Comparing the Effects of Two Perturbation-Based Balance Training Paradigms in Fall-Prone Older Adults: A Randomized Controlled Trial.

INTRODUCTION: There is increasing evidence that perturbation-based balance training (PBT) is highly effective in preventing falls at older age. Different PBT paradigms have been presented so far, yet a systematic comparison of PBT approaches with respect to feasibility and effectiveness is missing. Two different paradigms of PBT seem to be promising for clinical implementation: (1) technology-supported training on a perturbation treadmill (PBTtreadmill); (2) training of dynamic stability mechanisms in the presence of perturbations induced by unstable surfaces (PBTstability). This study aimed to compare both program's feasibility and effectiveness in fall-prone older adults. METHODS: In this three-armed randomized controlled trial, seventy-one older adults (74.9 ± 6.0 years) with a verified fall risk were randomly assigned into three groups: PBTtreadmill on a motorized treadmill, PBTstability using unstable conditions such as balance pads, and a passive control group (CG). In both intervention groups, participants conducted a 6-week intervention with 3 sessions per week. Effects were assessed in fall risk (Brief-BEST), balance ability (Stepping Threshold Test, center of pressure, limits of stability), leg strength capacity, functional performance (Timed Up and Go Test, Chair-Stand), gait (preferred walking speed), and fear of falling (Short FES-I). RESULTS: Fifty-one participants completed the study. Training adherence was 91% for PBTtreadmill and 87% for PBTstability, while no severe adverse events occurred. An analysis of covariance with an intention-to-treat approach revealed statistically significant group effects in favor of PBTstability in the Brief-BEST (p = 0.009, η2 = 0.131) and the limits of stability (p = 0.020, η2 = 0.110) and in favor of PBTtreadmill in the Stepping Threshold Test (p < 0.001, η2 = 0.395). The other outcomes demonstrated no significant group effects. CONCLUSION: Both training paradigms demonstrated high feasibility and were effective in improving specific motor performances in the fall-prone population and these effects were task specific. PBTtreadmill showed higher improvements in reactive balance, which might have been promoted by the unpredictable nature of the included perturbations and the similarity to the tested surface perturbation paradigm. PBTstability showed more wide-ranging effects on balance ability. Consequently, both paradigms improved fall risk-associated measures. The advantages of both formats should be evaluated in light of individual needs and preferences. Larger studies are needed to investigate the effects of these paradigms on real-life fall rates.

"Can Do" vs. "Do Do" in Older Adults: A Cross-Sectional Analysis of Sensor-Derived Physical Activity Patterns.

(1) Background: Identifying groups with a misaligned physical capacity (PC) and physical activity (PA) is potentially relevant for health promotion. Although an important health determinant, deeper knowledge of underlying walking behavior patterns in older adults is currently missing. We aim to identify specific PA signatures of misaligned groups and determine PA variables discriminating between groups. (2) Methods: In total, 294 community-dwelling older adults (≥70 years) were divided into four quadrants based on thresholds for PA (≥ or <5000 steps/day) and PC (≤ or >12 s, Timed Up and Go test). Kruskal-Wallis and effect sizes were calculated to compare quadrants' PA variables and to determine the discriminative power of PA parameters on walking duration, frequency, and intensity. (3) Results: We identified quadrant-specific PA signatures. Compared with "can do-do do", the "cannot do-do do" group performs shorter continuous and lower-intensity walks; the "can do-do not do" group takes fewer steps and walks with less intensity. The "cannot do-do not do" group presents lower values in all PA variables. "Walking duration greater or equal 3 METs" was the strongest discriminative PA variable. (4) Conclusion: We provide distinct PA signatures for four clinically different groups of older adults. Walking intensity is most useful to distinguish community-dwelling older adults, which is relevant for developing improved customized health promotion interventions.

Comparison of falls and cost-effectiveness of the group versus individually delivered Lifestyle-integrated Functional Exercise (LiFE) program: final results from the LiFE-is-LiFE non-inferiority trial.

BACKGROUND: the individually delivered Lifestyle-integrated Functional Exercise (LiFE) was shown to improve physical activity (PA) and reduce fall incidence, however being rather resource-consuming due to one-to-one delivery. A potentially less resource-intensive group format (gLiFE) was developed and compared against the original program, considering higher risk of falling due to possible PA enhancement. OBJECTIVE: to investigate non-inferiority in terms of PA-adjusted fall risk and cost-effectiveness of gLiFE at 12-month follow-up. DESIGN: single-blinded, randomised, multi-centre non-inferiority trial. SETTING: community. SUBJECTS: in total, 309 adults aged 70+ years at risk of or with history of falling; n = 153 in gLiFE, n = 156 in LiFE. METHODS: LiFE was delivered one-to-one at the participants' homes, gLiFE in a group. PA-adjusted fall risk was analysed using negative binomial regression to compare incidence rate ratios (IRR). Cost-effectiveness was presented by incremental cost-effectiveness ratios and cost-effectiveness acceptability curves, considering quality-adjusted life years, PA and falls as effect measures. Secondary analyses included PA (steps/day) and fall outcomes. RESULTS: non-inferiority was inconclusive (IRR 0.96; 95% confidence interval, CI 0.67; 1.37); intervention costs were lower for gLiFE, but cost-effectiveness was uncertain. gLiFE participants significantly increased PA (+1,090 steps/day; 95% CI 345 and 1.835) versus insignificant increase in LiFE (+569, 95% CI -31; 1,168). Number of falls and fallers were reduced in both formats. CONCLUSION: non-inferiority of gLiFE compared with LiFE was inconclusive after 12 months. Increases in PA were clinically relevant in both groups, although nearly twice as high in gLiFE. Despite lower intervention costs of gLiFE, it was not clearly superior in terms of cost-effectiveness.

Changes in Psychological Determinants of Behavior Change after Individual versus Group-Based Lifestyle-integrated Fall Prevention: Results from the LiFE-is-LiFE Trial.

OBJECTIVE: The Lifestyle-integrated Functional Exercise (LiFE) intervention has been shown to promote physical activity in fall-prone older adults. However, the underlying mechanisms of how LiFE functions remain unclear. This study compares the effects of the individual and group-based LiFE formats on psychological determinants of behavior change derived from the health action process approach, habit formation theory, and self-determination theory. METHODS: Secondary analysis on basis of the randomized, non-inferiority LiFE-is-LiFE trial were performed. Questionnaire data on psychological determinants were obtained from older adults (M = 78.8 years, range 70-95) who took part in either the individual (n = 156) or the group-based (n = 153) LiFE intervention. Measurement points varied from three to six times, and from baseline (T1) up to a 12-month follow-up (T6). A generalized linear mixed model was specified for each determinant. RESULTS: Both LiFE and gLiFE participants reported lower levels of motivational determinants at T6. LiFE participants showed significantly higher values of action planning and coping planning at T6. Participants in both formats showed increased levels of action control at T6, whereas participants' habit strength decreased post-intervention but then stabilized over time. LiFE participants showed higher levels of autonomy, competence, and relatedness throughout the study, but levels of intrinsic motivation did not differ between formats and from T1 to T6. CONCLUSION: In both formats, but especially in the individual LiFE, the behavior change techniques used affected volitional rather than motivational or general determinants of behavior change. Habit strength as an important indicator of the sustainability of the LiFE exercises stabilized over time, indicating that participants, at least partly, sustained their formed habits long-term.

Willingness to pay for a group and an individual version of the Lifestyle-integrated Functional Exercise program from a participant perspective.

BACKGROUND: Perceived benefits of intervention programs from a participant perspective can be examined by assessing their willingness to pay (WTP). Aiming to support decision-makers in their decision to implement a fall prevention program, this study examined (1) the WTP for a group-based and an individually delivered fall prevention program, (2) which factors influence WTP, and (3) whether the WTP exceeds the intervention costs. METHODS: WTP was elicited using Payment Cards from 237 individuals who participated in a randomized non-inferiority trial (LiFE-is-LiFE) comparing a group version of the Lifestyle-integrated Functional Exercise program (gLiFE) with the individually delivered version (LiFE). Linear regression models were used to examine factors associated with WTP. The net benefit for (g)LiFE was calculated as the difference between WTP and intervention costs, assuming different scenarios of intervention costs (varying group sizes of gLiFE) and hypothetical subsidy levels by a payer (€0, €50, or €75). RESULTS: The mean WTP was €196 (95% CI [172, 221]) for gLiFE and €228 (95% CI [204, 251]) for LiFE. In the linear regression model, WTP was significantly associated with delivery format (-€32, 95% CI [- 65, - 0.2], for gLiFE) and net household income (+ 68€, 95% CI [23, 113], for ≥€3000 compared to <€2000). The net benefit for gLiFE was positive in most cases. Due to higher intervention costs of LiFE compared to gLiFE (€298 vs. €113), the net benefit for LiFE was negative for the majority of the sample, even at a subsidy of €75. CONCLUSION: The results provide insight into how valuable the interventions are perceived by the participants and thereby may be used by decision-makers as complement to cost-effectiveness analyses. WTP for both programs was generally high, probably indicating that participants perceived the intervention as quite valuable. However, further research is needed on the WTP and net benefit of fall prevention programs, as results relied on the specific context of the LiFE-is-LiFE trial.

Group-Based and Individually Delivered LiFE: Content Evaluation and Predictors of Training Response - A Dose-Response Analysis.

Introduction: Lifestyle-integrated Functional Exercise (LiFE) is an effective, individually delivered fall prevention program but comes with substantial resource requirements; hence, a group-format was developed (gLiFE). This study 1) evaluates the program content of two different LiFE formats (group vs individual) and 2) examines the relationship between predictors of training response (dose) and improvements in balance, strength, and physical activity (PA) (response). Material and Methods: The analysis included n = 252 (gLiFE = 126, LiFE = 126) community-dwelling older adults (78.6±5.2 years). LiFE was administered in seven sessions either in a group (gLiFE: 8-12 participants) or individually at home (LiFE). Questionnaire-based, descriptive content evaluation (frequency distributions) included reported frequency of practice (days/week, number of activities), activity preferences, safety, intensity, integrability of activities, and acceptance after 6 months of LiFE practice. Predictors (ie, dose [reported frequency and intensity], safety, and integrability of activities) for improvements in balance, strength, and PA were analyzed using radar charts. Results: In both formats, 11.2 activities were practiced on average. Strength activities were more frequently selected than balance. Content evaluation showed some marginal advantages for the LiFE participants for selected aspects. The effects on balance, strength, and PA were nearly similar in both groups. Participants who performed balance activities more frequently (≥4 days/week) scored better in the balance and PA domain. Those who performed strength activities more frequently (≥4 days/week) performed better in all three outcomes. Higher perceived safety was associated with better performance. Those who reported activities as "not physically exhausting" performed better in all three outcomes. Those who found activities easily integrable into daily routines scored higher in the balance and strength domain. Discussion and Conclusion: Overall, both program formats are comparable with respect to content evaluation and effects. Participants need to perceive the activities as safe, not exhausting, and should practice ≥4 days/week to generate a high benefit from the intervention. Trial Registration: ClinicalTrials.gov, NCT03462654. Registered on 12 March 2018.

Wearable Motion Sensors in Older Adults: On the Cutting Edge of Health and Mobility Research.

Wearable motion sensors have been gaining ground for quite some time now; a large proportion of research projects in the field of physical activity, health, and mobility are being carried out using an electronic form of outcome assessment, and there are good reasons for this [...].

Cost-Effectiveness of a Group vs Individually Delivered Exercise Program in Community-Dwelling Persons Aged ≥70 Years.

OBJECTIVES: Interventions aimed at reducing falls and physical inactivity could alleviate the economic burden attributable to these factors. The study aimed to analyze the cost-effectiveness of a group-delivered version of the Lifestyle-integrated Functional Exercise Program compared with an individually delivered program version. DESIGN: An economic evaluation conducted alongside the LiFE-is-LiFE randomized non-inferiority trial. INTERVENTIONS: Group and individually delivered version of a program consisting of strength and balance exercises integrated into everyday activities to prevent falls. SETTING AND PARTICIPANTS: 309 community-dwelling older adults (aged ≥70 years) at risk of falling recruited around Heidelberg and Stuttgart (Germany). METHODS: Cost-effectiveness of the group program was assessed over 6 months using different effect measures [quality-adjusted life years (QALYs, EQ-5D-5L), physical activity (mean number of steps/day), and falls] and cost perspectives (societal and payer's). Incremental cost-effectiveness ratios were determined, and cost-effectiveness acceptability curves were constructed. RESULTS: From a societal perspective, mean costs, the number of falls, and the number of steps/day were somewhat higher in the group program, whereas QALYs were almost identical between the 2 interventions. From the payer's perspective, the incremental cost-effectiveness ratio for the group compared to the individual program were €56,733 per QALY and €4755 per fall prevented. Based on the cost-effectiveness acceptability curves, the cost-effectiveness of the group program had to be rated as uncertain for both effect measures and perspectives. In contrast, it demonstrated cost-effectiveness for increasing physical activity at willingness-to-pay values per additional 1000 steps/day of €1600 (societal perspective) or €600 (payer's perspective). CONCLUSIONS AND IMPLICATIONS: Compared to the individual program, the group program might be cost-effective for increasing physical activity in older adults but was unlikely to be cost-effective with regard to QALY or for preventing falls. The cost-effectiveness should be evaluated long-term and compared to a regular care group.

The Stepping Threshold Test for Reactive Balance: Validation of Two Observer-Based Evaluation Strategies to Assess Stepping Behavior in Fall-Prone Older Adults.

Introduction: Measurement of reactive balance is critical for fall prevention but is severely underrepresented in the clinical setting due to the lack of valid assessments. The Stepping Threshold Test (STT) is a newly developed instrumented test for reactive balance on a movable platform, however, it has not yet been validated for fall-prone older adults. Furthermore, different schemes of observer-based evaluation seem possible. The aim of this study was to investigate validity with respect to fall risk, interpretability, and feasibility of the STT using two different evaluation strategies. Methods: This study involved 71 fall-prone older adults (aged ≥ 65) who underwent progressively increasing perturbations in four directions for the STT. Single and multiple-step thresholds for each perturbation direction were determined via two observer-based evaluation schemes, which are the 1) consideration of all steps (all-step-count evaluation, ACE) and 2) consideration of those steps that extend the base of support in the direction of perturbation (direction-sensitive evaluation, DSE). Established balance measures including global (Brief Balance Evaluations Systems Test, BriefBEST), proactive (Timed Up and Go, TUG), and static balance (8-level balance scale, 8LBS), as well as fear of falling (Short Falls Efficacy Scale-International, FES-I) and fall occurrence in the past year, served as reference measurements. Results: The sum scores of STT correlated moderately with the BriefBEST (ACE: r = 0.413; DSE: r = 0.388) and TUG (ACE: r = -0.379; DSE: r = -0.435) and low with the 8LBS (ACE: r = 0.173; DSE: r = 0.246) and Short FES-I (ACE: r = -0.108; DSE: r = -0.104). The sum scores did not distinguish between fallers and non-fallers. No floor/ceiling effects occurred for the STT sum score, but these effects occurred for specific STT thresholds for both ACE (mean floor effect = 13.04%, SD = 19.35%; mean ceiling effect = 4.29%, SD = 7.75%) and DSE (mean floor effect = 7.86%, SD = 15.23%; mean ceiling effect = 21.07%, SD = 26.08). No severe adverse events occurred. Discussion: Correlations between the STT and other balance tests were in the expected magnitude, indicating convergent validity. However, the STT could not distinguish between fallers and non-fallers, referring to a need for further studies and prospective surveys of falls to validate the STT. Current results did not allow a definitive judgment on the advantage of using ACE or DSE. Study results represented a step toward a reactive balance assessment application in a clinical setting.

Influence of Cognitive Impairment on Rehabilitation Received and Its Mediating Effect on Functional Recovery.

BACKGROUND: Cognitive impairment (CI) has been reported to negatively impact rehabilitation outcomes. Knowledge about differences in rehabilitation received in dependence of CI as a potential mediating factor is limited. OBJECTIVE: To analyze whether CI affects amount and frequency of rehabilitation received and if associations between CI and rehabilitation outcome are mediated by the provided amount of therapy. METHODS: Observational cohort study in ward-based geriatric rehabilitation consecutively including 373 patients (mean age 82.0±6.69 years, mean MMSE 23.66±5.31). Outcome measures were amount, frequency, and type of multi-professional therapy sessions and rehabilitation outcome assessed with the Barthel Index (BI). Cognitive status was measured with the Mini-Mental-State Examination (MMSE) classifying three patient subgroups according to cognitive status. RESULTS: Patients with more severe CI received least total therapy hours (TTH) (MMSE < 17, 13.67±6.58 versus MMSE 17-26, 16.12±7.19 and MMSE > 26, 17.79±8.88 h, p = 0.014) and were less often included in occupational therapy (MMSE < 17, 48.9%versus MMSE 17-26, 65.5%and MMSE > 26, 71.4%, p = 0.019) and group-based physiotherapy (MMSE < 17, 73.3%versus MMSE 17-26, 88.5%and MMSE > 26, 81.2%, p = 0.027). Regression models showed that CI negatively impacted TTH (ß= 0.24, p = 0.003) and rehabilitation outcome (ß= 0.41, p = 0.008). In the mediation model, TTH accounted for 23.18%(p < 0.001) of the relationship between CI and rehabilitation outcome. CONCLUSION: Cognitive impairment negatively impacted rehabilitation received. The lower TTH partly mediated the negative association between CI and rehabilitation outcome. Future research should identify specific barriers to therapy provision and optimal length, intensity, and dosage of rehabilitation programs to optimize rehabilitation outcomes in CI.

Lifestyle-integrated functional exercise to prevent falls and promote physical activity: Results from the LiFE-is-LiFE randomized non-inferiority trial.

BACKGROUND: The 'Lifestyle-integrated Functional Exercise' (LiFE) program successfully reduced risk of falling via improvements in balance and strength, additionally increasing physical activity (PA) in older adults. Generally being delivered in an individual one-to-one format, downsides of LiFE are considerable human resources and costs which hamper large scale implementability. To address this, a group format (gLiFE) was developed and analyzed for its non-inferiority compared to LiFE in reducing activity-adjusted fall incidence and intervention costs. In addition, PA and further secondary outcomes were evaluated. METHODS: Older adults (70 + years) at risk of falling were included in this multi-center, single-blinded, randomized non-inferiority trial. Balance and strength activities and means to enhance PA were delivered in seven intervention sessions, either in a group (gLiFE) or individually at the participant's home (LiFE), followed by two "booster" phone calls. Negative binomial regression was used to analyze non-inferiority of gLiFE compared to LiFE at 6-month follow-up; interventions costs were compared descriptively; secondary outcomes were analyzed using generalized linear models. Analyses were carried out per protocol and intention-to-treat. RESULTS: Three hundred nine persons were randomized into gLiFE (n = 153) and LiFE (n = 156). Non-inferiority of the incidence rate ratio of gLiFE was inconclusive after 6 months according to per protocol (mean = 1.27; 95% CI: 0.80; 2.03) and intention-to-treat analysis (mean = 1.18; 95% CI: 0.75; 1.84). Intervention costs were lower for gLiFE compared to LiFE (-€121 under study conditions; -€212€ under "real world" assumption). Falls were reduced between baseline and follow-up in both groups (gLiFE: -37%; LiFE: -55%); increases in PA were significantly higher in gLiFE (+ 880 steps; 95% CI 252; 1,509). Differences in other secondary outcomes were insignificant. CONCLUSIONS: Although non-inferiority of gLiFE was inconclusive, gLiFE constitutes a less costly alternative to LiFE and it comes with a significantly larger enhancement of daily PA. The fact that no significant differences were found in any secondary outcome underlines that gLiFE addresses functional outcomes to a comparable degree as LiFE. Advantages of both formats should be evaluated in the light of individual needs and preferences before recommending either format. TRIAL REGISTRATION: The study was preregistered under clinicaltrials.gov (identifier: NCT03462654 ) on March 12th 2018.