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.

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 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.

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.

Robustness of In-Laboratory and Daily-Life Gait Speed Measures over One Year in High Functioning 61- to 70-Year-Old Adults.

INTRODUCTION: Gait speed is a simple and safe measure with strong predictive value for negative health outcomes in clinical practice, yet in-laboratory gait speed seems not representative for daily-life gait speed. This study aimed to investigate the interrelation between and robustness of in-laboratory and daily-life gait speed measures over 12 months in 61- to 70-year-old adults. METHODS: Gait speed was assessed in laboratory through standardized stopwatch tests and in daily life by 7 days of trunk accelerometry in the PreventIT cohort, at baseline, and after 6 and 12 months. The interrelation was investigated using Pearson's correlations between gait speed measures at each time point. For robustness, changes over time and variance components were assessed by ANOVA and measurement agreement over time by Bland-Altman analyses. RESULTS: Included were 189 participants (median age 67 years [interquartile range: 64-68], 52.2% females). In-laboratory and daily-life gait speed measures showed low correlations (Pearson's r = 0.045-0.455) at each time point. Moreover, both in-laboratory and daily-life gait speed measures appeared robust over time, with comparable and smaller within-subject than between-subject variance (range 0.001-0.095 m/s and 0.032-0.397 m/s, respectively) and minimal differences between measurements over time (Bland-Altman) with wide limits of agreement (standard deviation of mean difference range: 0.12-0.34 m/s). DISCUSSION/CONCLUSION: In-laboratory and daily-life gait speed measures show robust assessments of gait speed over 12 months and are distinct constructs in this population of high-functioning adults. This suggests that (a combination of) both measures may have added value in predicting health outcomes.

Sensitivity to Change and Responsiveness of the Original and the Shortened Version of the Community Balance and Mobility Scale for Young Seniors.

OBJECTIVE: To examine sensitivity to change and responsiveness of the Community Balance and Mobility Scale (CBM) and shortened CBM (s-CBM). DESIGN: Secondary analysis using data of a randomized controlled trial. SETTING: General community. PARTICIPANTS: Young community-dwelling seniors aged 61-70 years (N=134; mean age, 66.2±2.5y). INTERVENTIONS: Participants underwent 12 months of exercise intervention. MAIN OUTCOME MEASURES: CBM and s-CBM. Sensitivity to change was assessed using standardized response mean (SRM) and paired t tests as appropriate. Responsiveness was assessed using 2 minimal important difference (MID) estimates. Analyses were conducted for the full sample and for the subgroups "high-balance" and "low-balance," divided by median split. RESULTS: Inferential statistics revealed a significant CBM (P<.001) and s-CBM (P<.001) improvement within the full sample and the subgroups (high-balance: P=.001, P=.019; low-balance: P<.001, P<.001). CBM and s-CBM were moderately sensitive to change (SRM, 0.48 vs 0.38) within the full sample. In the high-balance subgroup, moderate SRM values (0.70) were found for the CBM and small values for the s-CBM (0.29). In the low-balance subgroup, moderate SRM values were found for the CBM (0.67) and high values for the s-CBM (0.80). For the full sample, CBM and s-CBM exceeded the lower but not the higher MID value. In the high-balance subgroup, the CBM exceeded both MID values, but the s-CBM exceeded only the lower. In the low-balance subgroup, CBM and s-CBM exceeded both MID values. CONCLUSIONS: The CBM is a suitable tool to detect intervention-related changes of balance and mobility in young, high-performing seniors. Both versions of the CBM scale show good sensitivity to change and responsiveness, particularly in young seniors with low balance.

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).

Perturbation-based gait training to improve daily life gait stability in older adults at risk of falling: protocol for the REACT randomized controlled trial.

BACKGROUND: The European population is rapidly ageing. There is an urgent need for innovative solutions to reduce fall risk in older adults. Perturbation-based gait training is a promising new method to improve reactive balance responses. Whereas positive effects on task-specific dynamic balance recovery during gait have been shown in clinical or laboratory settings, translation of these effects to daily life gait function and fall risk is limited. We aim to evaluate the effect of a 4-week perturbation-based treadmill training on daily-life dynamic gait stability, assessed with inertial sensor data. Secondary outcomes are balance recovery performance, clinical balance and gait assessment scores, the amount of physical activity in daily life and falls incidence during 6 months follow-up. METHODS: The study is a monocenter assessor-blinded randomized controlled trial. The target study sample consists of 70 older adults of 65 years and older, living in the community and with an elevated risk of falling. A block-randomization to avoid seasonal effects will be used to allocate the participants into two groups. The experimental group receives a 4-week, two times per week perturbation-based gait training programme on a treadmill, with simulated slips and trips, in combination with cognitive dual tasks. The control group receives a 4-week, two times per week treadmill training programme under cognitive dual-task conditions without perturbations. Participants will be assessed at baseline and after the 4-weeks intervention period on their daily-life gait stability by wearing an inertial sensor on the lower back for seven consecutive days. In addition, clinical balance and gait assessments as well as questionnaires on falls- and gait-efficacy will be taken. Daily life falls will be followed up over 6 months by a fall calendar. DISCUSSION: Whereas perturbation-based training has shown positive effects in improving balance recovery strategies and in reducing laboratory falls, this study will contribute to investigate the translation of perturbation-based treadmill training effects in a clinical setting towards improving daily life gait stability and reducing fall risk and falls. TRIAL REGISTRATION: NTR7703 / NL66322.028.18, Registered: January 8, 2019; Enrolment of the first participant April 8, 2019.

Association between Daily-Life Gait Quality Characteristics and Physiological Fall Risk in Older People.

Gait quality characteristics obtained from accelerometry during daily life are predictive of falls in older people but it is unclear how they relate to fall risk. Our aim was to test whether these gait quality characteristics are associated with the severity of fall risk. We collected one week of trunk accelerometry data from 279 older people (aged 65-95 years; 69.5% female). We used linear regression to investigate the association between six daily-life gait quality characteristics and categorized physiological fall risk (QuickScreen). Logarithmic rate of divergence in the vertical (VT) and anteroposterior (AP) direction were significantly associated with the level of fall risk after correction for walking speed (both p < 0.01). Sample entropy in VT and the mediolateral direction and the gait quality composite were not significantly associated with the level of fall risk. We found significant differences between the high fall risk group and the very low- and low-risk groups, the moderate- and very low-risk and the moderate and low-risk groups for logarithmic rate of divergence in VT and AP (all p ≤ 0.01). We conclude that logarithmic rate of divergence in VT and AP are associated with fall risk, making them feasible to assess the physiological fall risk in older people.

The Adapted Lifestyle-Integrated Functional Exercise Program for Preventing Functional Decline in Young Seniors: Development and Initial Evaluation.

BACKGROUND: The Lifestyle-integrated Functional Exercise (LiFE) program is an intervention integrating balance and strength activities into daily life, effective at reducing falls in at-risk people ≥70 years. There is potential for LiFE to be adapted to young seniors in order to prevent age-related functional decline. OBJECTIVE: We aimed to (1) develop an intervention by adapting Lifestyle-integrated Functional Exercise (aLiFE) to be more challenging and suitable for preventing functional decline in young seniors in their 60s and (2) perform an initial feasibility evaluation of the program. Pre-post changes in balance, mobility, and physical activity (PA) were also explored. METHODS: Based on a conceptual framework, a multidisciplinary expert group developed an initial aLiFE version, including activities for improving strength, neuromotor performances, and PA. Proof-of-concept was evaluated in a 4-week pre-post intervention study measuring (1) feasibility including adherence, frequency of practice, adverse events, acceptability (i.e., perceived helpfulness, adaptability, level of difficulty of single activities), and safety, and (2) changes in balance/mobility (Community Balance and Mobility Scale) and PA (1 week activity monitoring). The program was refined based on the study results. RESULTS: To test the initial aLiFE version, 31 young seniors were enrolled and 30 completed the study (mean age 66.4 ± 2.7 years, 60% women). Of a maximum possible 16 activities, participants implemented on average 12.1 ± 1.8 activities during the intervention, corresponding to mean adherence of 76%. Implemented activities were practiced 3.6-6.1 days/week and 1.8-7.8 times/day, depending on the activity type. One noninjurious fall occurred during practice, although the participant continued the intervention. The majority found the activities helpful, adaptable to individual lifestyle, appropriately difficult, and safe. CMBS score increased with medium effect size (d = 0.72, p = 0.001). Increase in daily walking time (d = 0.36) and decrease in sedentary time (d = -0.10) were nonsignificant. Refinements included further increasing the task challenge of some strength activities and defining the most preferred activities in the trainer's manual to facilitate uptake of the program. CONCLUSION: aLiFE has the potential to engage young seniors in regular lifestyle-integrated activities. Effectiveness needs to be evaluated in a randomized controlled trial.

Development of a clinical prediction model for the onset of functional decline in people aged 65-75 years: pooled analysis of four European cohort studies.

BACKGROUND: Identifying those people at increased risk of early functional decline in activities of daily living (ADL) is essential for initiating preventive interventions. The aim of this study is to develop and validate a clinical prediction model for onset of functional decline in ADL in three years of follow-up in older people of 65-75 years old. METHODS: Four population-based cohort studies were pooled for the analysis: ActiFE-ULM (Germany), ELSA (United Kingdom), InCHIANTI (Italy), LASA (Netherlands). Included participants were 65-75 years old at baseline and reported no limitations in functional ability in ADL at baseline. Functional decline was assessed with two items on basic ADL and three items on instrumental ADL. Participants who reported at least some limitations at three-year follow-up on any of the five items were classified as experiencing functional decline. Multiple logistic regression analysis was used to develop a prediction model, with subsequent bootstrapping for optimism-correction. We applied internal-external cross-validation by alternating the data from the four cohort studies to assess the discrimination and calibration across the cohorts. RESULTS: Two thousand five hundred sixty community-dwelling people were included in the analyses (mean age 69.7 ± 3.0 years old, 47.4% female) of whom 572 (22.3%) reported functional decline at three-year follow-up. The final prediction model included 10 out of 22 predictors: age, handgrip strength, gait speed, five-repeated chair stands time (non-linear association), body mass index, cardiovascular disease, diabetes, chronic obstructive pulmonary disease, arthritis, and depressive symptoms. The optimism-corrected model showed good discrimination with a C statistic of 0.72. The calibration intercept was 0.06 and the calibration slope was 1.05. Internal-external cross-validation showed consistent performance of the model across the four cohorts. CONCLUSIONS: Based on pooled cohort data analyses we were able to show that the onset of functional decline in ADL in three years in older people aged 65-75 years can be predicted by specific physical performance measures, age, body mass index, presence of depressive symptoms, and chronic conditions. The prediction model showed good discrimination and calibration, which remained stable across the four cohorts, supporting external validity of our findings.

Catch the ruler: concurrent validity and test-retest reliability of the ReacStick measures of reaction time and inhibitory executive function in older people.

BACKGROUND: Reduced cognitive function, particularly executive function (EF), is associated with an increased risk of falling in older people. We evaluated the utility of the ReacStick test, a clinical test of reaction time, and inhibitory EF developed, for young athletes, for fall-risk assessment in older people. AIMS: To evaluate the psychometric properties of ReacStick measures of reaction time and executive functioning in healthy community-dwelling older people. METHODS: 140 participants (aged 77 ± 5 years) underwent testing. Two test conditions-simple and inhibitory go/no-go-provided measures of reaction time, recognition load (difference in reaction time between conditions), and go/no-go accuracy. Concurrent validity was evaluated against the conventional tests of reaction time and EF (simple hand reaction time, trail-making test, and Stroop colour test). Discriminant ability was determined for fall-risk factors (age, gender, physiological profile assessment, and fall history). Test-retest reliability after 1 week was evaluated in 30 participants. RESULTS: ReacStick reaction time correlated with tests of reaction time and EF, recognition load correlated with inhibitory EF, and go accuracy correlated with reaction time and inhibitory EF. No-go accuracy was not significantly correlated with any of the reaction time and EF tests. Test-retest reliability was good-to-excellent (ICC > 0.6) for all the outcomes. ReacStick reaction time discriminated between groups based on age, recognition load between genders, and no-go accuracy between retrospective fallers and non-fallers. DISCUSSION: An unavoidable time pressure may result in complementary information to the traditional measures. CONCLUSIONS: The ReacStick is a reliable test of reaction time and inhibitory EF in older people and could have value for fall-risk assessment.

Quality of Daily-Life Gait: Novel Outcome for Trials that Focus on Balance, Mobility, and Falls.

Technological advances in inertial sensors allow for monitoring of daily-life gait characteristics as a proxy for fall risk. The quality of daily-life gait could serve as a valuable outcome for intervention trials, but the uptake of these measures relies on their power to detect relevant changes in fall risk. We collected daily-life gait characteristics in 163 older people (aged 77.5 ± 7.5, 107♀) over two measurement weeks that were two weeks apart. We present variance estimates of daily-life gait characteristics that are sensitive to fall risk and estimate the number of participants required to obtain sufficient statistical power for repeated comparisons. The provided data allows for power analyses for studies using daily-life gait quality as outcome. Our results show that the number of participants required (i.e., 8 to 343 depending on the anticipated effect size and between-measurements correlation) is similar to that generally used in fall prevention trials. We propose that the quality of daily-life gait is a promising outcome for intervention studies that focus on improving balance and mobility and reducing falls.

Comparison of Standard Clinical and Instrumented Physical Performance Tests in Discriminating Functional Status of High-Functioning People Aged 61⁻70 Years Old.

Assessment of physical performance by standard clinical tests such as the 30-sec Chair Stand (30CST) and the Timed Up and Go (TUG) may allow early detection of functional decline, even in high-functioning populations, and facilitate preventive interventions. Inertial sensors are emerging to obtain instrumented measures that can provide subtle details regarding the quality of the movement while performing such tests. We compared standard clinical with instrumented measures of physical performance in their ability to distinguish between high and very high functional status, stratified by the Late-Life Function and Disability Instrument (LLFDI). We assessed 160 participants from the PreventIT study (66.3 ± 2.4 years, 87 females, median LLFDI 72.31, range: 44.33⁻100) performing the 30CST and TUG while a smartphone was attached to their lower back. The number of 30CST repetitions and the stopwatch-based TUG duration were recorded. Instrumented features were computed from the smartphone embedded inertial sensors. Four logistic regression models were fitted and the Areas Under the Receiver Operating Curve (AUC) were calculated and compared using the DeLong test. Standard clinical and instrumented measures of 30CST both showed equal moderate discriminative ability of 0.68 (95%CI 0.60⁻0.76), p = 0.97. Similarly, for TUG: AUC was 0.68 (95%CI 0.60⁻0.77) and 0.65 (95%CI 0.56⁻0.73), respectively, p = 0.26. In conclusion, both clinical and instrumented measures, recorded through a smartphone, can discriminate early functional decline in healthy adults aged 61⁻70 years.

Predicting Trajectories of Functional Decline in 60- to 70-Year-Old People.

BACKGROUND: Early identification of people at risk of functional decline is essential for delivering targeted preventive interventions. OBJECTIVE: The aim of this study is to identify and predict trajectories of functional decline over 9 years in males and females aged 60-70 years. METHODS: We included 403 community-dwelling participants from the InCHIANTI study and 395 from the LASA study aged 60-70 years at baseline, of whom the majority reported no functional decline at baseline (median 0, interquartile range 0-1). Participants were included if they reported data on ≥2 measurements of functional ability during a 9-year follow-up. Functional ability was scored with 6 self-reported items on activities of daily living. We performed latent class growth analysis to identify trajectories of functional decline and applied multinomial regression models to develop prediction models of identified trajectories. Analyses were stratified for sex. RESULTS: Three distinct trajectories were identified: no/little decline (219 males, 241 females), intermediate decline (114 males, 158 females), and severe decline (36 males, 30 females). Higher gait speed showed decreased risk of functional limitations in males (intermediate limitations, odds ratio [OR] 0.74, 95% CI 0.57-0.97; severe limitations, OR 0.42, 95% CI 0.26-0.66). The final model in males further included the predictors fear of falling and alcohol intake (no/little decline, area under the receiver operating curve [AUC] 0.68, 95% CI 0.62-0.73; intermediate decline, AUC 0.63, 95% CI 0.56-0.69; severe decline, AUC 0.79, 95% CI 0.71-0.87). In females, higher gait speed showed a decreased risk of intermediate limitations (OR 0.51, 95% CI 0.38-0.68) and severe limitations (OR 0.18, 95% CI 0.07-0.44). Other predictors in females were age, living alone, economic satisfaction, balance, physical activity, BMI, and cardiovascular disease (no/little decline, AUC 0.80, 95% CI 0.75-0.85; intermediate decline, AUC 0.74, 95% CI 0.69-0.79; severe decline, AUC 0.95, 95% CI 0.91-0.99). CONCLUSION: Already in people aged 60-70 years, 3 distinct trajectories of functional decline were identified in these cohorts over a 9-year follow-up. Predictors of trajectories differed between males and females, except for gait speed. Identification of people at risk is the basis for targeting interventions.

Muscle mass and muscle strength are associated with pre- and post-hospitalization falls in older male inpatients: a longitudinal cohort study.

BACKGROUND: Low muscle mass and strength are highly prevalent in inpatients. It is acknowledged that low muscle mass and strength are associated with falls in community-dwelling older adults, but it is unknown if these muscle measures are also associated with falls in a population of older inpatients. This study aimed to investigate the association between muscle measures and pre- and post-hospitalization falls in older inpatients. METHODS: An inception cohort of patients aged 70 years and older, admitted to an academic teaching hospital, was included in this study. Muscle mass and hand grip strength were measured at admission using bioelectrical impedance analysis and handheld dynamometry. Pre-hospitalization falls were dichotomized as having had at least one fall in the six months prior to admission. Post-hospitalization falls were dichotomized as having had at least one fall during the three months after discharge. Associations were analysed with logistic regression analysis. RESULTS: The study cohort comprised 378 inpatients (mean age, SD: 79.7, 6.4 years). Fifty per cent of female and 41% of male patients reported at least one fall prior to hospitalization. Post-hospitalization, 18% of female and 23% of male patients reported at least one fall. Lower muscle mass was associated with post-hospitalization falls, and lower hand grip strength was associated with both pre- and post-hospitalization falls in male, but not in female, patients. CONCLUSIONS: These findings confirm the likely involvement of muscle mass and strength in the occurrence of pre- and post-hospitalization falls in a population of older inpatients, but only in males.

Concurrent validity and reliability of the Community Balance and Mobility scale in young-older adults.

BACKGROUND: With the growing number of young-older adults (baby-boomers), there is an increasing demand for assessment tools specific for this population, which are able to detect subtle balance and mobility deficits. Various balance and mobility tests already exist, but suffer from ceiling effects in higher functioning older adults. A reliable and valid challenging balance and mobility test is critical to determine a young-older adult's balance and mobility performance and to timely initiate preventive interventions. The aim was to evaluate the concurrent validity, inter- and intrarater reliability, internal consistency, and ceiling effects of a challenging balance and mobility scale, the Community Balance and Mobility Scale (CBM), in young-older adults aged 60 to 70 years. METHODS: Fifty-one participants aged 66.4 ± 2.7 years (range, 60-70 years) were assessed with the CBM. The Fullerton Advanced Balance scale (FAB), 3-Meter Tandem Walk (3MTW), 8-level balance scale, Timed-Up-and-Go (TUG), and 7-m habitual gait speed were used to estimate concurrent validity, examined by Spearman correlation coefficient (ρ). Inter- and intrarater reliability were calculated as Intra-class-correlations (ICC), and internal consistency by Cronbach alpha and item-total correlations (ρ). Ceiling effects were determined by obtaining the percentage of participants reaching the highest possible score. RESULTS: The CBM significantly correlated with the FAB (ρ = 0.75; p < .001), 3MTW errors (ρ = - 0.61; p < .001), 3MTW time (ρ = - 0.35; p = .05), the 8-level balance scale (ρ = 0.35; p < .05), the TUG (ρ = - 0.42; p < .01), and 7-m habitual gait speed (ρ = 0.46, p < .001). Inter- (ICC2,k = 0.97), intrarater reliability (ICC3,k = 1.00) were excellent, and internal consistency (α = 0.88; ρ = 0.28-0.81) was good to satisfactory. The CBM did not show ceiling effects in contrast to other scales. CONCLUSIONS: Concurrent validity of the CBM was good when compared to the FAB and moderate to good when compared to other measures of balance and mobility. Based on this study, the CBM can be recommended to measure balance and mobility performance in the specific population of young-older adults. TRIAL REGISTRATION: Trial number: ISRCTN37750605 . (Registered on 21/04/2016).

The association between age and accelerometry-derived types of habitual daily activity: an observational study over the adult life span in the Netherlands.

BACKGROUND: Advances in sensor technology allow for objective and high-resolution monitoring of physical activity and sedentary behaviour. Novel epidemiological data is required to provide feedback on an individual's habitual daily activity in comparison to peers and might eventually lead to refined physical activity guidelines. METHODS: We merged data of 762 people between 18 and 99 years of age, who all wore a DynaPort MoveMonitor accelerometer on their lower back during 1 week in daily-life, to provide insight into habitual types and durations of daily activities, and examine the association between age and physical activity and sedentary behaviour. RESULTS: We found associations between age and almost all activity outcomes. These associations suggested that physical activity declines and sedentary behaviour increases from the age of 50. We further describe an association with gender, with men walking more often in fewer but longer bouts and having fewer, longer bouts of sitting and standing. CONCLUSIONS: These data provide a valuable reference and may call for more age- and gender-specific activity interventions.

Deep Learning to Predict Falls in Older Adults Based on Daily-Life Trunk Accelerometry.

Early detection of high fall risk is an essential component of fall prevention in older adults. Wearable sensors can provide valuable insight into daily-life activities; biomechanical features extracted from such inertial data have been shown to be of added value for the assessment of fall risk. Body-worn sensors such as accelerometers can provide valuable insight into fall risk. Currently, biomechanical features derived from accelerometer data are used for the assessment of fall risk. Here, we studied whether deep learning methods from machine learning are suited to automatically derive features from raw accelerometer data that assess fall risk. We used an existing dataset of 296 older adults. We compared the performance of three deep learning model architectures (convolutional neural network (CNN), long short-term memory (LSTM) and a combination of these two (ConvLSTM)) to each other and to a baseline model with biomechanical features on the same dataset. The results show that the deep learning models in a single-task learning mode are strong in recognition of identity of the subject, but that these models only slightly outperform the baseline method on fall risk assessment. When using multi-task learning, with gender and age as auxiliary tasks, deep learning models perform better. We also found that preprocessing of the data resulted in the best performance (AUC = 0.75). We conclude that deep learning models, and in particular multi-task learning, effectively assess fall risk on the basis of wearable sensor data.