Cognitive function is associated with the development of mobility impairments in community-dwelling elders

Real-life intrinsic capacity screening data from the ICOPE-Care program

The Integrated Care for Older People (ICOPE) program is a healthcare pathway that uses a screening test for intrinsic capacity (IC) as its entry point. However, real-life data informing on how IC domains cluster and change over time, as well as their clinical utility, are lacking. Using primary healthcare screening data from more than 20,000 French adults 60 years of age or older, this study identified four clusters of IC impairment: 'Low impairment' (most prevalent), 'Cognition+Locomotion+Hearing+Vision', 'All IC impaired' and 'Psychology+Vitality+Vision'. Compared to individuals with 'Low impairment', those in the other clusters had higher likelihood of having frailty and limitations in both activities of daily living (ADL) and instrumental activities of daily living (IADL), with the strongest associations being observed for 'All IC impaired'. This study found that ICOPE screening might be a useful tool for patient risk stratification in clinical practice, with a higher number of IC domains impaired at screening indicating a higher probability of functional decline.

Estimating the Effect of Engagement in Community-Based Going-Out Program on Incidence Disability in Older Adults

OBJECTIVES

Although going out has been reported to be associated with the incidence of disability, few studies have investigated the effect of community-based programs to promote going out on the incidence of disability. This study aimed to estimate the effects of a program fostering going-out on the incidence of disability in community-dwelling older adults.

DESIGN

Longitudinal, observational study.

SETTING AND PARTICIPANTS

Nonengaged (n = 1086) and engaged older adults (n = 1086) enrolled in the National Center for Geriatrics and Gerontology Study of Geriatric Syndrome by using a one-to-one nearest neighbor propensity score-matching scheme.

METHODS

After the baseline assessments, participants in the community-based going-out program received a specialized physical activity tracker, monitored their daily physical activity, and received personalized feedback on going out to community facilities with a system for reading the device for 12 months. Disability onset was defined as a new case of long-term care under the public insurance certification in Japan within 48 months of program completion. The absolute risk reduction and the number needed to treat for the incidence of disability were calculated for the nonengaged and engaged groups. Cox proportional hazard regression analysis, using inverse probability weighting was used to obtain the hazard ratio.

RESULTS

Disabilities occurred in 112 individuals in the matched nonengaged group and 51 individuals in the engaged group. The absolute risk reduction was 5.67% (95% CI 3.46%-7.88%). The number needed to treat was 18 (95% CI 13-29). The hazard ratio, with the nonengaged group as the reference, was 0.49 (95% CI 0.36-0.67).

CONCLUSIONS AND IMPLICATIONS

This longitudinal observational study suggested that a community-based program could prevent 1 disability in every 18 participants. This program does not require a professional instructor, only the distribution of devices and system installation, and it could be beneficial as a population-based approach to preventing disabilities.

Meta-Analysis-Based Comparison of Annual Fall Risk between Older Adults with Alzheimer's Disease and Mild Cognitive Impairment

Background

Falls are a primary cause of injuries and hospitalization in older adults. It has been reported that cognitive impairments and dementia can increase fall risk in the older population; however, it remains unknown if fall risk differs among subgroups of dementia. This meta-analysis summarized previous studies reporting the annual fall risk of people with Alzheimer's disease (AD) or mild cognitive impairment (MCI) and compared the fall risk between these two groups of people with dementia.

Methods

Thirty-five studies enrolling 7844 older adults with AD or MCI were included. The annual fall prevalence and average number of falls of the included studies were meta-analyzed and compared by random-effects models with inverse variance weights.

Results

The annual fall prevalence in people with AD (43.55%) was significantly higher than MCI (35.26%, p < 0.001). A χ2 test indicated that the pooled fall prevalence is significantly higher in people with AD than MCI χ2 = 158.403, p < 0.001). Additionally, the yearly average number of falls in AD was higher than in MCI (1.30 vs 0.77 falls/person).

Conclusions

The results showed that older people with AD experience a higher annual fall prevalence with a larger number of falls than older adults with MCI. The results suggested that the fall risk measurements should be reported separately between people with AD and MCI. The findings could provide preliminary guidance for the identification of individuals with dementia who experience a high fall risk.

Links across disabilities: unveiling associations between functional domains

BACKGROUND

Persons with disabilities experience higher risks of mortality as well as poorer health as compared to the general population. The aim of this study is to estimate the correlations between functional difficulties across several domains in six countries.

METHODS

National census data with questions on disability from six countries (Mauritius, Morocco, Senegal, Myanmar, Vietnam, and Uruguay) was used in this study. We performed logistic regressions to assess the extent to which having a functional difficulty in one domain is correlated with having a functional difficulty in each of the other domains and report weighted odds ratios (ORs) overall and within age-groups ('18-44' years and '45+' years). Models adjust for age, sex, and location (rural or urban). Sensitivity analyses around different choices of predictors and response variables were conducted.

FINDINGS

For all countries, reporting a functional difficulty in one domain was consistently and significantly positively correlated with reporting a functional difficulty in other domains (overall) and for each of the two age-groups considered - '18-44' years and '45+' years. All ORs were greater than one. Cognition, mobility, and hearing were the domains that were the most correlated ones with other domains. The highest pairwise correlations were for i/ hearing and cognition; ii/ mobility and cognition. Results were robust to changing the severity thresholds for functional difficulties. Across countries, Uruguay, the only high-income country among the six countries under study, had the lowest correlations between functional domains.

CONCLUSIONS

There are consistent positive associations in the experience of functional difficulties in various domains in the six countries under study. Such correlations may reflect barriers to social services including healthcare services and resources (e.g. assistive devices) that may lead to an avoidable deterioration of functioning across domains. Further research is needed on the trajectories of functional difficulties and on structural barriers that people with functional difficulties may experience in their communities and in healthcare settings in particular. This is important as some functional difficulties may be preventable.

What Do Older Canadians Think They Need to Walk Well?

Purpose

To identify older Canadians' perception of the importance of expert-generated elements of walking quality, and the contributors to and consequences of perceived walking quality.

Method

Cross-sectional survey of 649 adults was conducted through a commercial participant panel, Hosted in Canada Surveys.

Results

Of the 649 respondents, 75% were between 65 and 74 years old (25% ≥ 75) and 49% were women. The most important elements were foot, ankle, hip, and knee mobility with little difference in ranks across walking perception (Fr χ12 = 5.0, p > 0.05). People who were older by a decade were more likely to report poorer walking (POR: 1.4; 95% CI: 1.0, 1.7), as were women compared to men, and people who used a walking aid compared to none. Lung disease showed the highest association with a perception of not walking well (POR: 7.2; 95% CI: 3.7, 14.2). The odds of being willing to pay more for a technology to improve walking were always greater for those with a lower perception of their walking quality.

Conclusions

People who perceived their walking quality as poor were more likely to report poorer health and were willing to pay more for a technology to improve walking. This supports the opportunity of leveraging wearable technologies to improve walking.

The Effects of Exergaming on Executive and Physical Functions in Older Adults With Dementia: Randomized Controlled Trial

BACKGROUND

Despite increasing interest in the effects of exergaming on cognitive function, little is known about its effects on older adults with dementia.

OBJECTIVE

The purpose of this is to investigate the effects of exergaming on executive and physical functions in older adults with dementia compared to regular aerobic exercise.

METHODS

In total, 24 older adults with moderate dementia participated in the study. Participants were randomized into either the exergame group (EXG, n=13, 54%) or the aerobic exercise group (AEG, n=11, 46%). For 12 weeks, EXG engaged in a running-based exergame and AEG performed a cycling exercise. At baseline and postintervention, participants underwent the Ericksen flanker test (accuracy % and response time [RT]) while recording event-related potentials (ERPs) that included the N2 and P3b potentials. Participants also underwent the senior fitness test (SFT) and the body composition test pre- and postintervention. Repeated-measures ANOVA was performed to assess the effects of time (pre- vs postintervention), group (EXG vs AEG), and group×time interactions.

RESULTS

Compared to AEG, EXG demonstrated greater improvements in the SFT (F_1.22=7.434, P=.01), reduction in body fat (F_1.22=6.476, P=.02), and increase in skeletal mass (F_1.22=4.525, P=.05), fat-free mass (F_1.22=6.103, P=.02), and muscle mass (F_1.22=6.636, P=.02). Although there was a significantly shorter RT in EXG postintervention (congruent P=.03, 95% CI 13.581-260.419, incongruent P=.04, 95% CI 14.621-408.917), no changes occurred in AEG. EXG also yielded a shorter N2 latency for central (Cz) cortices during both congruent conditions compared to AEG (F_1.22=4.281, P=.05). Lastly, EXG presented a significantly increased P3b amplitude compared to AEG during the Ericksen flanker test (congruent: frontal [Fz] F_1.22=6.546, P=.02; Cz F_1.22=5.963, P=.23; parietal [Pz] F_1.22=4.302, P=.05; incongruent: Fz F_1.22=8.302, P=.01; Cz F_1.22=15.199, P=.001; Pz F_1.22=13.774, P=.001).

CONCLUSIONS

Our results suggest that exergaming may be associated with greater improvements in brain neuronal activity and enhanced executive function task performance than regular aerobic exercise. Exergaming characterized by both aerobic exercise and cognitive stimulation can be used as an effective intervention to improve cognitive and physical functions in older adults with dementia.

TRIAL REGISTRATION

Clinical Research Information Service KCT0008238; https://cris.nih.go.kr/cris/search/detailSearch.do/24170.

Balance performance and grip strength as predictors of cognitive function among community-dwelling older adults in the USA

Objectives

To investigate how balance and grip strength predicts the probability of cognitive function impairment (i.e., executive function: mild and mild-to-moderate impairment, and delayed recall) over eight years in community-dwelling older adults in the US, controlling for sex and race/ethnicity.

Methods

The National Health and Aging Trends Study dataset (2011 - 2018) was employed. Dependent variables included the Clock Drawing Test (Executive Function) and Delayed Word Recall Test. Longitudinal ordered logistic regression examined the association between cognitive function and predictors (i.e., balance and grip strength) over eight waves (n=9800, 1,225 per wave).

Results

Those who could complete side-by-side standing and semi-tandem tasks were 33% and 38% less likely to have mild or mild-to-moderate executive function impairment, respectively, relative to those who could not complete these tests. One score decrease in grip strength increased the executive function impairment risk by 13% (Odds Ratio: 0.87, CI: 0.79-0.95). Those who completed the side-by-side tasks were 35% (Odds Ratio: 0.65, CI: 0.44-0.95) less likely to experience delayed recall impairments than those who could not complete this test. With one score decrease in grip strength, the risk of delayed recall impairment was increased by 11% (OR: 0.89, CI: 0.80-1.00).

Conclusions

A combination of these two simple tests (i.e., semi-tandem stance and grip strength) can screen for cognitive impairment among community-dwelling older adults to identify people with mild and mild-to-moderate cognitive impairment in clinical settings.

Age-related changes in gait biomechanics and their impact on the metabolic cost of walking: Report from a National Institute on Aging workshop

Changes in old age that contribute to the complex issue of an increased metabolic cost of walking (mass-specific energy cost per unit distance traveled) in older adults appear to center at least in part on changes in gait biomechanics. However, age-related changes in energy metabolism, neuromuscular function and connective tissue properties also likely contribute to this problem, of which the consequences are poor mobility and increased risk of inactivity-related disease and disability. The U.S. National Institute on Aging convened a workshop in September 2021 with an interdisciplinary group of scientists to address the gaps in research related to the mechanisms and consequences of changes in mobility in old age. The goal of the workshop was to identify promising ways to move the field forward toward improving gait performance, decreasing energy cost, and enhancing mobility for older adults. This report summarizes the workshop and brings multidisciplinary insight into the known and potential causes and consequences of age-related changes in gait biomechanics. We highlight how gait mechanics and energy cost change with aging, the potential neuromuscular mechanisms and role of connective tissue in these changes, and cutting-edge interventions and technologies that may be used to measure and improve gait and mobility in older adults. Key gaps in the literature that warrant targeted research in the future are identified and discussed.

Temporal Trends (from 2008 to 2017) in Functional Limitations and Limitations in Activities of Daily Living: Findings from a Nationally Representative Sample of 5.4 Million Older Americans

This study's objectives are as follows: (1) to identify the temporal trends in the prevalence and the odds of activities of daily living (ADL) limitations and functional limitations (FLs) among Americans aged 65 and older; (2) to explore if these trends vary by gender and age cohort; (3) to determine if generational differences in educational attainment play a role in the observed temporal trends. A secondary analysis of the American Community Survey (ACS) was conducted for ten consecutive waves of the annual cross-sectional survey (2008-2017). The respondents were community-dwelling and institutionalized adults aged 65 and older (n = 5.4 million). The question on ADLs was "Does this person have difficulty dressing or bathing?". The question on FLs was "Does this person have serious difficulty walking or climbing stairs?". There was a substantial decline over the decade in the prevalence of ADL limitations, from 12.1% to 9.6%, and FLs, from 27.3% to 23.5%. If the 2017 prevalence rates had remained at the same level as the 2008 prevalence rates, there would have been an additional 1.27 million older Americans with ADL limitations and 1.89 million with FLs. Adjusting for educational attainment substantially attenuated the odds of the decline for both ADL limitations and FLs.

Cognitive, psychological and social factors associated with older adults' mobility: a scoping review of self-report and performance-based measures

Although many factors have been associated with mobility among older adults, there is paucity of research that explores the complexity of factors that influence mobility. This review aims to synthesise the available evidence for factors comprising the cognitive, psychological, and social mobility determinants and their associations with mobility self-reported and performance-based outcomes in older adults (60 years). We followed Arksey and O'Malley's five stages of a scoping review and searched PubMed, EMBASE, PsychINFO, Web of Science, AgeLine, Allied and Complementary Medicine Database, Cumulative Index to Nursing and Allied Health Literature and Sociological Abstract databases. Reviewers in pairs independently conducted title, abstract, full-text screening and data extraction. We reported associations by analyses rather than articles because articles reported multiple associations for factors and several mobility outcomes. Associations were categorised as significantly positive, negative, or not significant. We included 183 peer-reviewed articles published in 27 countries, most of which were cross-sectional studies and conducted among community-dwelling older adults. The 183 articles reported 630 analyses, of which 381 (60.5%) were significantly associated with mobility outcomes in the expected direction. For example, older adults with higher cognitive functioning such as better executive functioning had better mobility outcomes (e.g., faster gait speed), and those with poor psychological outcomes, such as depressive symptoms, or social outcomes such as reduced social network, had poorer mobility outcomes (e.g., slower gait speed) compared to their counterparts. Studies exploring the association between cognitive factors, personality (a psychological factor) and self-reported mobility outcomes (e.g., walking for transportation or driving), and social factors and performance-based mobility outcomes in older adults are limited. Understanding the additive relationships between cognitive, psychological, and social factors highlights the complexity of older adults' mobility across different forms of mobility, including independence, use of assistive devices, transportation, and driving.

Effect of Number of Household Members on Falls among Disabled Older People

Objectives: To investigate the effect of the number of cohabitating household members on falls among an disabled aging Korean population. Methods: We used data from the first to the fourth waves of the Korea Longitudinal Study of Aging. Using the first wave at baseline, data included 1414 individuals aged 45 years and older who needed assistance for performance of activities of daily living (ADL) or instrumental activities of daily living (IADL). We classified falls as overall falls, falls requiring medical treatment, and hip fractures caused by falls. The number of cohabitating family members was classified as none (living alone), one, two, or more. A generalized estimating equation with logit link was used to examine the association between the number of cohabitating household members with overall falls and injuries caused by falls. Results: Compared to living with two or more household members, living alone was associated with higher odds of overall falls, falls needing medical treatment, and hip fractures caused by falls (odds ratio (OR) 2.13, 95% confidence interval [CI] 1.36–3.34; OR 2.13, 95% CI 1.28–3.53; OR 1.93, 95% CI 1.01–3.69, respectively). These associations were particularly strong in individuals with cognitive decline. Conclusions Living alone is associated with higher odds of overall falls, falls needing medical treatment, and hip fractures caused by falls, particularly for those with cognitive decline. Conclusions: Intervention programs to prevent falls in disabled, aging adults, especially those living alone and those with declined cognitive function, need to provide home care services and promote the use of safety equipment.

Association of Statins With Cerebral Atherosclerosis and Incident Parkinsonism in Older Adults

BACKGROUND AND OBJECTIVES

The burden of cerebrovascular disease pathologies is associated with progressive parkinsonism in older adults. We tested the hypothesis that older adults using statins have a lower risk of developing parkinsonism.

METHODS

We studied older adults with annual clinical testing of 4 parkinsonian signs and assessment of statin use based on inspection of all medications. Parkinsonism was present if there was clinical evidence of ≥2 parkinsonian signs. Postmortem brain examination collected indices of pathologies, including atherosclerosis of the large vessels of the circle of Willis. We examined whether baseline statin use was related to incident parkinsonism. Then in decedents, we examined whether statin use before death was related to pathologies and whether pathologies linked the association of statin use to parkinsonism.

RESULTS

Mean age of the participants (n = 2,841) at study baseline was 76.3 years (SD 7.4 years), and 75% were women. During an average follow-up of 6 years (mean 5.6 years, SD 4.9 years), 50% (n = 1,432) of participants developed parkinsonism. Statin use at baseline (n = 936) was associated with a lower risk of parkinsonism (hazard ratio 0.84, 95% CI 0.74-0.96, p = 0.008), controlling for demographics, vascular risk factors, and diseases. Among the decedents (n = 1,044, mean age at death 89.2 years, SD 6.7 years), statin use before death was associated with a lower odds of atherosclerosis (odds ratio [OR] 0.63, 95% CI 0.50-0.79, p < 0.001). In a mediation analysis, both a direct (OR 0.73, 95% CI 0.54-0.93, p = 0.008) and an indirect (OR 0.92, 95% CI 0.88-0.97, p = 0.002) pathway via less severe atherosclerosis linked statins to parkinsonism, indicating that atherosclerosis mediated 17% of the association between statins and parkinsonism.

DISCUSSION

Adults using statins have a lower risk of parkinsonism that may be partially mediated by a lower odds of brain atherosclerosis. These findings highlight the role of cerebrovascular pathologies in late-life parkinsonism and suggest a potential role for statins in decreasing its magnitude.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that statin use is associated with a lower risk of parkinsonism in older adults.

High temporal resolution measurements of movement reveal novel early-life physiological decline in C. elegans

Age-related physiological changes are most notable and best-studied late in life, while the nature of aging in early- or middle-aged individuals has not been explored as thoroughly. In C. elegans, many studies of movement vs. age generally focus on three distinct phases: sustained, youthful movement; onset of rapidly progressing impairment; and gross immobility. We investigated whether this first period of early-life adult movement is a sustained “healthy” level of high function followed by a discrete “movement catastrophe”—or whether there are early-life changes in movement that precede future physiological declines. To determine how movement varies during early adult life, we followed isolated individuals throughout life with a previously unachieved combination of duration and temporal resolution. By tracking individuals across the first six days of adulthood, we observed declines in movement starting as early as the first two days of adult life, as well as high interindividual variability in total daily movement. These findings suggest that movement is a highly dynamic behavior early in life, and that factors driving movement decline may begin acting as early as the first day of adulthood. Using simulation studies based on acquired data, we suggest that too-infrequent sampling in common movement assays limits observation of early-adult changes in motility, and we propose feasible strategies and a framework for designing assays with increased sensitivity for early movement declines.

Assessment of a Robotic Walker in Older Adults With Parkinson's Disease in Daily Living Activities

The constant growth of the population with mobility impairments, such as older adults and people suffering from neurological pathologies like Parkinson's disease (PD), has encouraged the development of multiple devices for gait assistance. Robotic walkers have emerged, improving physical stability and balance and providing cognitive aid in rehabilitation scenarios. Different studies evaluated human gait behavior with passive and active walkers to understand such rehabilitation processes. However, there is no evidence in the literature of studies with robotic walkers in daily living scenarios with older adults with Parkinson's disease. This study presents the assessment of the AGoRA Smart Walker using Ramps Tests and Timed Up and Go Test (TUGT). Ten older adults participated in the study, four had PD, and the remaining six had underlying conditions and fractures. Each of them underwent a physical assessment (i.e., Senior Fitness, hip, and knee strength tests) and then interacted with the AGoRA SW. Kinematic and physical interaction data were collected through the AGoRA walker's sensory interface. It was found that for lower limb strength tests, older adults with PD had increases of at least 15% in all parameters assessed. For the Sit to Stand Test, the Parkinson's group evidenced an increase of 23%, while for the Chair Sit and Reach Test (CSRT), this same group was only 0.04 m away from reaching the target. For the Ramp Up Test (RUT), the subjects had to make a greater effort, and significant differences (p-value = 0.04) were evidenced in the force they applied to the device. For the Ramp Down Test (RDT), the Parkinson's group exhibited a decrease in torque, and there were statistically significant differences (p-value = 0.01) due to the increase in the complexity of the task. In the Timed Up and Go Test (TUGT), the subjects presented significant differences in torque (p-value of 0.05) but not in force (p-value of 0.22) due to the effect of the admittance controller implemented in the study. Finally, the results suggested that the walker, represents a valuable tool for assisting people with gait motor deficits in tasks that demanded more physical effort adapting its behavior to the specific needs of each user.

Usability Study of a Multicomponent Exergame Training for Older Adults with Mobility Limitations

The global population aged 60 years and over rises due to increasing life expectancy. More older adults suffer from “geriatric giants”. Mobility limitations, including immobility and instability, are usually accompanied by physical and cognitive decline, and can be further associated with gait changes. Improvements in physical and cognitive functions can be achieved with virtual reality exergame environments. This study investigated the usability of the newly developed VITAAL exergame in mobility-impaired older adults aged 60 years and older. Usability was evaluated with a mixed-methods approach including a usability protocol, the System Usability Scale, and a guideline-based interview. Thirteen participants (9 female, 80.5 ± 4.9 years, range: 71–89) tested the exergame and completed the measurement. The System Usability Scale was rated in a marginal acceptability range (58.3 ± 16.5, range: 30–85). The usability protocol and the guideline-based interview revealed general positive usability. The VITAAL exergame prototype received positive feedback and can be considered usable by older adults with mobility limitations. However, minor improvements to the system in terms of design, instructions, and technical aspects should be taken into account. The results warrant testing of the feasibility of the adapted multicomponent VITAAL exergame, and its effects on physical and cognitive functions, in comparison with conventional training, should be studied.

Effects of cognitive workload on heart and locomotor rhythms coupling

Different physiological signals could be coupled under specific conditions, in some cases related to pathologies or reductions in system complexity. Cardiac-locomotor synchronization (CLS) has been one of the most investigating coupling. The influence of a cognitive task on walking was investigated in dual-task experiments, but how different cognitive tasks may influence CLS has poorly been investigated. Twenty healthy subjects performed a dual-task walking (coupled with verbal fluency vs calculation) on a treadmill at three different speeds (comfortable speed CS; fast-speed: CS + 2 km/h; slow-speed: CS-2 km/h) while cardiac and walking rhythms were recorded using surface electrodes and a triaxial accelerometer, respectively. According to previous studies, we found a cognitive-motor interference for which cognitive performance was affected by motor exercise, but not vice-versa. We found a CLS at the baseline condition, at fast speed in both cognitive tasks, while at comfortable speed only for the verbal fluency task. In conclusion, the cardiac and locomotor rhythms were not coupled at slow speed and at comfortable speed during subtraction task. Cognitive performances generally increased at faster speed, when cardiac locomotor coupling was stronger.

Effects of Attentional Control on Gait and Inter-Joint Coordination During Dual-Task Walking

In the process of walking, attentional resources are flexibly allocated to deal with varying environmental constraints correlated with attentional control (AC). A dual-task paradigm was used to investigate the effects of AC on gait and inter-joint coordination. Fifty students volunteered to participate in this study. Based on the reaction time (RT) in the Stroop task, the top 15 participants were assigned to the High Attentional Control (HAC) group, while the last 15 participants were assigned to the Low Attentional Control (LAC) group. The participants in the two groups were randomly asked to perform three tasks: (i) single 2-back working memory task (ST 2-back); (ii) single walking task (ST walking); and (iii) dual task (DT). Cognitive outcomes and gait spatiotemporal parameters were measured. Continuous relative phase (CRP), derived from phase angles of two adjacent joints, was used to assess inter-joint coordination. The LAC group exhibited significant task effects regarding RT, correct rate (CR), step width, gait cycle, step time, forefoot contact times, heel-forefoot times, hip-knee mean absolute relative phase (MARP), and deviation phase (DP) in the stance and swing phases (p < 0.05). In the HAC group, significant task effects were only detected in RT and foot progression angle of the left foot (p < 0.05). Under the three task conditions, the LAC group exhibited a higher CR in ST, longer heel contact times, and longer heel-forefoot times when compared with the LAC group (p < 0.05). Compared with the LAC group, the HAC group exhibited significantly smaller (closer to zero) MARP and weaker hip-knee DP values in the swing phase across all gait conditions (p < 0.05). In the stance phase, the HAC group had smaller MARP (closer to zero) values when compared with the LAC group (p < 0.05). In conclusion, the ability to maintain gait control and modulate inter-joint coordination patterns in young adults is affected by the level of attentional control in accommodating gait disturbances. AC is correlated with the performance of motor control, which theoretically supports the competitive selection of athletes and fall prevention strategies for a specific population.

Age Moderates Differences in Performance on the Instrumented Timed Up and Go Test Between People With Dementia and Their Informal Caregivers

BACKGROUND AND PURPOSE

The instrumented Timed Up and Go test (iTUG) affords quantification of the subelements of the Timed Up and Go test to assess fall risk and physical performance. A miniature sensor applied to the back is able to capture accelerations and velocities from which the subelements of the iTUG can be quantified. This study is the first to compare iTUG performance between people with dementia (PWD) and their age-matched caregivers. The aims of this study were to explore how age moderates the differences in performance on the iTUG between PWD and their informal caregivers.

METHODS

Eight-three community-dwelling older PWD and their informal caregivers were recruited for this cross-sectional, observational study. Participants were grouped by age: younger than 70 years, 70 to 79 years, and 80 years and older. Participants wore an inertial sensor while performing the iTUG in their home. The performance of the subelements sit-to-stand, walking, and turning were captured through an algorithm converting accelerations and velocities into performance metrics such as duration and peak velocity. Performance for PWD was compared with caregivers for each age-matched group, and multiple regression models incorporating age, gender, and presence or absence of dementia were computed.

RESULTS

People with dementia took longer to turn in the younger than 70-year group, suggesting this may be an early indicator of functional decline in this age group. People with dementia took longer to complete the whole iTUG compared with caregivers in the 70- to 79-year-old group. In the 80+-year-old group, PWD took longer to complete both walking phases, sit-to-stand, and the full iTUG along with displaying slower turning velocity. Multiple regression models illustrated that gender failed to contribute significantly to the model, but age and presence of dementia explained around 30% of the variance of time to complete walking phases, total iTUG, and turning velocity.

CONCLUSIONS

Differences were evident in performance of the iTUG between PWD and caregivers even after controlling for age. Age moderates the differences observed in performance.

Evaluation of Physical Interaction during Walker-Assisted Gait with the AGoRA Walker: Strategies Based on Virtual Mechanical Stiffness

Smart walkers are commonly used as potential gait assistance devices, to provide physical and cognitive assistance within rehabilitation and clinical scenarios. To understand such rehabilitation processes, several biomechanical studies have been conducted to assess human gait with passive and active walkers. Several sessions were conducted with 11 healthy volunteers to assess three interaction strategies based on passive, low and high mechanical stiffness values on the AGoRA Smart Walker. The trials were carried out in a motion analysis laboratory. Kinematic data were also collected from the smart walker sensory interface. The interaction force between users and the device was recorded. The force required under passive and low stiffness modes was 56.66% and 67.48% smaller than the high stiffness mode, respectively. An increase of 17.03% for the hip range of motion, as well as the highest trunk’s inclination, were obtained under the resistive mode, suggesting a compensating motion to exert a higher impulse force on the device. Kinematic and physical interaction data suggested that the high stiffness mode significantly affected the users’ gait pattern. Results suggested that users compensated their kinematics, tilting their trunk and lower limbs to exert higher impulse forces on the device.

Association between coffee consumption and functional disability in older US adults

The effect of coffee consumption on functional disability has been scarcely investigated. Thus, this study aimed to examine the association between coffee consumption and functional disability in older American adults. Participants (≥60 years old, n 7704) were from the National Health and Nutrition Examination Survey 2007-2016. Coffee consumption was assessed through two 24-h dietary recall interviews. Five domains of functional disability including lower extremity mobility (LEM), general physical activity (GPA), leisure and social activities (LSA), activities of daily living (ADL) and instrumental activities of daily living (IADL) were self-reported. Age- and multivariate-adjusted logistic regression models and restricted cubic spline analyses were used. Total coffee consumption was inversely associated with LEM, GPA, LSA and IADL disability. Compared with non-drinkers of total coffee, those who consumed ≥2 cups/d reported lower odds of LEM (OR 0·67, 95 % CI 0·50, 0·91), GPA (OR 0·65, 95 % CI 0·47, 0·88), LSA (OR 0·61, 95 % CI 0·45, 0·83) and IADL (OR 0·59, 95 % CI 0·44, 0·78) disability. The dose-response analyses confirmed these relationships. Intake of ≥2 cups/d caffeinated coffee was also inversely linked to GPA (OR 0·67, 95 % CI 0·48, 0·92), LSA (OR 0·66, 95 % CI 0·46, 0·93) and IADL (OR 0·57, 95 % CI 0·43, 0·75) disability, whereas the inverse association of 2+ cups/d decaffeinated coffee was only on LEM (OR 0·43, 95 % CI 0·23, 0·81) and LSA (OR 0·39, 95 % CI 0·16, 0·94) disability. The present study suggested that coffee consumption was inversely associated with functional disability in older American adults. Those associations of diverse coffee types differed across domains of functional disability.

Fluid Cognitive Abilities Are Important for Learning and Retention of a New, Explicitly Learned Walking Pattern in Individuals After Stroke

BACKGROUND

There is significant variability in poststroke locomotor learning that is poorly understood and affects individual responses to rehabilitation interventions. Cognitive abilities relate to upper extremity motor learning in neurologically intact adults, but have not been studied in poststroke locomotor learning.

OBJECTIVE

To understand the relationship between locomotor learning and retention and cognition after stroke.

METHODS

Participants with chronic (>6 months) stroke participated in 3 testing sessions. During the first session, participants walked on a treadmill and learned a new walking pattern through visual feedback about their step length. During the second session, participants walked on a treadmill and 24-hour retention was assessed. Physical and cognitive tests, including the Fugl-Meyer-Lower Extremity (FM-LE), Fluid Cognition Composite Score (FCCS) from the NIH Toolbox -Cognition Battery, and Spatial Addition from the Wechsler Memory Scale-IV, were completed in the third session. Two sequential regression models were completed: one with learning and one with retention as the dependent variables. Age, physical impairment (ie, FM-LE), and cognitive measures (ie, FCCS and Spatial Addition) were the independent variables.

RESULTS

Forty-nine and 34 participants were included in the learning and retention models, respectively. After accounting for age and FM-LE, cognitive measures explained a significant portion of variability in learning (R² = 0.17, P = .008; overall model R² = 0.31, P = .002) and retention (ΔR² = 0.17, P = .023; overall model R² = 0.44, P = .002).

CONCLUSIONS

Cognitive abilities appear to be an important factor for understanding locomotor learning and retention after stroke. This has significant implications for incorporating locomotor learning principles into the development of personalized rehabilitation interventions after stroke.

Cognitive decline negatively impacts physical function

Many older adults report difficulty performing one or more activities of daily living. These difficulties may be attributed to cognitive decline and as a result, measuring cognitive status among aging adults may help provide an understanding of current functional status. The purpose of the present investigation was to determine the association between cognitive status and measures of physical functioning. Seventy-six older adults participated in this study; 41 were categorized as normal memory function (NM) and 35 were poor memory function (PM). NM participants had significantly higher physical function as measured by Short Physical Performance Battery (SPPB; 9.4 ± 2.2 vs. 8.4 ± 2.0; p = .03) and peak velocity (0.67 ± 0.16 vs. 0.56 ± 0.19; p = .04) during a quick sit-to-stand task. Dual-task walking velocities were 22% and 126% slower between cognitive groups for the fast and habitual trials, respectively when compared to the single-task walking condition. Significant correlations existed between measures of memory and physical function. The largest correlations with memory were for peak (r = 0.42) and average (r = 0.38) velocity. The results suggest a positive relationship between physical function and cognitive status. However, further research is needed to determine the mechanism of the underlying relationships between physical and cognitive function.

Automatic Quantification of Tandem Walking Using a Wearable Device: New Insights Into Dynamic Balance and Mobility in Older Adults

BACKGROUND

Wearable sensors are increasingly employed to quantify diverse aspects of mobility. We developed novel tandem walking (TW) metrics, validated these measures using data from community-dwelling older adults, and evaluated their association with mobility disability and measures of gait and postural control.

METHODS

Six hundred ninety-three community-dwelling older adults (age: 78.69 ± 7.12 years) wore a 3D accelerometer on their lower back while performing 3 tasks: TW, usual-walking, and quiet standing. Six new measures of TW were extracted from the sensor data along with the clinician's conventional assessment of TW missteps (ie, trip other loss of balance in which recovery occurred to prevent a fall) and duration. Principal component analysis transformed the 6 new TW measures into 2 summary TW composite factors. Logistic regression models evaluated whether these TW factors were independently associated with mobility disability.

RESULTS

Both TW factors were moderately related to the TW conventional measures (r < 0.454, p < .001) and were mildly correlated with usual-walking (r < 0.195, p < .001) and standing, postural control (r < 0.119, p < .001). The TW frequency composite factor (p = .008), but not TW complexity composite factor (p = .246), was independently associated with mobility disability in a model controlling for age, sex, body mass index, race, conventional measures of TW, and other measures of gait and postural control.

CONCLUSIONS

Sensor-derived TW metrics expand the characterization of gait and postural control and suggest that they reflect a relatively independent domain of mobility. Further work is needed to determine if these metrics improve risk stratification for other adverse outcomes (eg, falls and incident disability) in older adults.

Physical fitness in institutionalized older adults with dementia: association with cognition, functional capacity and quality of life

This cross-sectional study investigated the association of physical fitness with cognitive function, functional capacity and quality of life among institutionalized older adults with dementia. One hundred and two older adults aged 78.0 ± 8.4 years, predominantly female (67.6%), with neurocognitive disorder due to Alzheimer's disease (AD) (49.2%), vascular dementia (14.7%), Parkinson's disease (2%), dementia with Lewy bodies (2%) or unspecified dementia (32.1%) participated in the present study. Regression analyses were used to examine associations between physical fitness components (Senior Fitness Test) and cognitive function (Mini-Mental State Examination), functional capacity (Katz Index of Independence in Activities of Daily Living) and Quality of Life (QoL)-Alzheimer's Disease scale. Univariate regression indicates that strength, flexibility, agility/dynamic balance and aerobic endurance are relevant for cognitive function, physical capacity and perceived QoL in institutionalized older people with dementia. After multiple regression analyses, adjusted for body mass index (BMI), results showed that aerobic endurance had a significant positive association with Total Katz Index. For both, caregiver perception of QoL-AD and global QoL-AD, BMI remained significantly and positively associated. Agility-dynamic balance presented a significant negative relation with global QoL-AD. Overall, our findings suggest that better physical fitness is important for cognition and autonomous functional capacity and that it has positive repercussions on the QoL in institutionalized older adults with dementia. Consequently, exercise-based therapeutic strategies aiming to improve physical fitness should be implemented.

Predicting Advanced Balance Ability and Mobility with an Instrumented Timed Up and Go Test

Extensive test batteries are often needed to obtain a comprehensive picture of a person’s functional status. Many test batteries are not suitable for active and healthy adults due to ceiling effects, or require a lot of space, time, and training. The Community Balance and Mobility Scale (CBMS) is considered a gold standard for this population, but the test is complex, as well as time- and resource intensive. There is a strong need for a faster, yet sensitive and robust test of physical function in seniors. We sought to investigate whether an instrumented Timed Up and Go (iTUG) could predict the CBMS score in 60 outpatients and healthy community-dwelling seniors, where features of the iTUG were predictive, and how the prediction of CBMS with the iTUG compared to standard clinical tests. A partial least squares regression analysis was used to identify latent components explaining variation in CBMS total score. The model with iTUG features was able to predict the CBMS total score with an accuracy of 85.2% (84.9–85.5%), while standard clinical tests predicted 82.5% (82.2–82.8%) of the score. These findings suggest that a fast and easily administered iTUG could be used to predict CBMS score, providing a valuable tool for research and clinical care.

Age-Varying Relationships Between Physical Function and Cognition in Older Adulthood

OBJECTIVES

There are positive relationships between physical and cognitive function in older adulthood; however, the strength of these relationships are inconsistent across studies. Although novel statistical tools provide flexibility to explore age-related differences in relationship magnitude, such methods have not been implemented in gerontological research. This study applied such methods to examine variations in relationship magnitude between physical function and cognition in healthy older adults (N = 2,783).

METHOD

Time-varying effects modeling (TVEM) is an extension of regression that models changes in relationships as a function of time-varying metrics like age. TVEM was used to examine if physical function (Turn 360, grip strength) predicted cognitive performance (memory, processing speed/attention, and reasoning) similarly across adults aged 65-90.

RESULTS

All associations between Turn 360 and all cognitive domains were significant and positive; however, speed of processing had significant magnitude variation across age such that the young-old and the old-old demonstrated the strongest relationships. Associations between grip strength and all cognitive domains significantly strengthened with increased age.

DISCUSSION

Results suggest that depending on the sample age, there may be inconsistencies in the relationships between physical and cognitive performance. Future research should explore these relationships longitudinally to better elucidate discrepant findings.

Correlation Between Cognition and Balance Among Middle-Aged and Older Adults Observed Through a Tai Chi Intervention Program

Background

Age-associated decline in cognition and balance may cause severe ability loss for daily living activities among middle-aged and older adults. The relationship between cognition and balance in this aging population remains to be explored.

Objective

The present study Is exploratory in nature and aimed to examine the relationship between balance (both static and dynamic components) and global cognitive function among middle-aged and older adults through Tai Chi (TC) practice as a research avenue.

Methods

A short-term (12 weeks) intervention of TC was conducted among middle-aged and older adults in the community setting. Global cognitive function (using the Chinese version of the Montreal Cognitive Assessment score (MoCA) and balance (i.e., one leg standing test score; Timed Up and Go Test score, TUGT) of all participants were assessed before and after the intervention. Age, body mass index (BMI), sex, and physical fitness variables (Chair Stand Test, CST; the 6-Meter Walk Test, 6MWT) were also collected as confounding factors.

Results

Significant moderator effects of baseline CST on the association between the dichotomized baseline MoCA score and the baseline left leg balance score (p = 0.0247), the baseline right leg balance score (p = 0.0140) and the baseline TUGT score (p = 0.0346) were found. Change score of left score balance (p = 0.0192) and change score of TUGT (p = 0.0162) were found to be significantly associated with change score of cognitive function.

Conclusion

Cognitive function and balance are interrelated in middle-aged and older adults. The association between global cognitive function and balance Is moderated by strength of lower limbs. The change scores of cognitive function and balance introduced by TC training were found to be positively correlated. Future research Is warranted to further confirm the cause-effect relationship of cognitive function and balance and its influencing factors among middle-aged and older adults utilizing intervention studies with larger sample sizes.

Smart and Assistive Walker - ASBGo: Rehabilitation Robotics: A Smart-Walker to Assist Ataxic Patients

Locomotion is an important human faculty that affects an individual's life, bringing not only physical and psychosocial implications but also heavy social-economic consequences. Thus, it becomes paramount to find means (augmentative/assistive devices) to empower the user's residual capacities and promote functional recovery.In this context, a smart walker (SW) is explored for further clinical evaluation of ataxic patients during walker-assisted and to serve as a functional compensation and assist-as-needed personalized/customized rehabilitation tool, autonomously adapting assistance to the users' needs, through innovative combination of real-time multimodal sensory information from SW built-in sensors. To meet the users' needs, its design was weighed, considering to whom it is intended.Thereby, this paper presents the system overview, focusing on design considerations, mechanical structure (frame and main components), electronic and mechatronic components, followed by its functionalities. Lastly, it presents results regarding the main functionalities, addressing clinical evidence.

Modifiable factors related to life-space mobility in community-dwelling older adults: results from the Canadian Longitudinal Study on Aging

BACKGROUND

The most common methods for measuring mobility in older adulthood include performance-based tests, such as the Timed-Up-and-Go and gait speed. While these measures have strong predictive validity for adverse outcomes, they are limited to assessing what older adults do in standardized settings, rather than what they do in their daily life. Life-space mobility, which is the ability to move within environments that expand from one's home to the greater community, has been proposed as a more comprehensive measure of mobility. The aim of this study was to determine the association between modifiable factors and life-space mobility in older adults enrolled in the Canadian Longitudinal Study on Aging (CLSA).

METHODS

Life-space mobility was measured using the Life Space Index (LSI). Explanatory factors included physical, psychosocial and cognitive determinants, as well as pain, fatigue, driving status, nutrition, body mass index, smoking status, and vision. To estimate the association between the LSI and explanatory variables, univariate and multivariable ordinary least squares regression analyses were performed.

RESULTS

All adults 65 years and older (n = 12,646) were included in the analysis. Fifty percent were women and the mean age was 73.0 (SD5.7). The mean LSI score was 80.5, indicating that, on average, the sample was able to move outside of their neighborhood independently. All explanatory variables were significantly associated with the LSI except for balance and memory. The top 3 variables that explained the most variation in the LSI were driving, social support and walking speed.

CONCLUSION

To our knowledge, this was the first study to examine the association between life-space mobility and a comprehensive set of modifiable factors that were selected based on a theoretical framework and existing research evidence. This study had two important messages. First, driving, social support and walking speed emerged as the most significant correlates of life-space mobility in older adults. Second, life-space mobility is multifactorial and interventions that are pragmatic in their design and testing are needed that consider the complexity involved. A multi-disciplinary approach to examining life-space mobility in older adults is needed to optimize opportunities for healthy aging and develop strategies that support mobility in older adulthood.

A Scoping Review of Physical Performance Outcome Measures Used in Exercise Interventions for Older Adults With Alzheimer Disease and Related Dementias

BACKGROUND AND PURPOSE

There is growing evidence that exercise interventions can mitigate functional decline and reduce fall risk in older adults with Alzheimer disease and related dementias (ADRD). Although physical performance outcome measures have been successfully used in older adults without cognitive impairment, additional research is needed regarding their use with individuals who have ADRD, and who may have difficulty following instructions regarding performance of these measures. The purpose of this scoping review was to identify commonly used physical performance outcome measures, for exercise interventions, that are responsive and reliable in older adults with ADRD. Ultimately, we aimed to provide recommendations regarding the use of outcome measures for individuals with ADRD across several domains of physical performance.

METHODS

A scoping review was conducted to broadly assess physical performance outcome measures used in exercise interventions for older adults with ADRD. Exercise intervention studies that included at least 1 measure of physical performance were included. All physical performance outcome measures were abstracted, coded, and categorized into 5 domains of physical performance: fitness, functional mobility, gait, balance, and strength. Criteria for recommendations were based on (1) the frequency of use, (2) responsiveness, and (3) reliability. Frequency was determined by the number of studies that used the outcome measure per physical performance domain. Responsiveness was assessed via calculated effect size of the outcome measures across studies within physical performance domains. Reliability was evaluated via published studies of psychometric properties.

RESULTS AND DISCUSSION

A total of 20 physical performance outcome measures were extracted from 48 articles that met study inclusion criteria. The most frequently used outcome measures were the 6-minute walk test, Timed Up and Go, repeated chair stand tests, short-distance gait speed, the Berg Balance Scale, and isometric strength measures. These outcome measures demonstrated a small, medium, or large effect in at least 50% of the exercise intervention studies. Good to excellent reliability was reported in samples of older adults with mild to moderate dementia. Fitness, functional mobility, gait, balance, and strength represent important domains of physical performance for older adults. The 6-minute walk test, Timed Up and Go, repeated chair stand tests, short-distance gait speed, Berg Balance Scale, and isometric strength are recommended as commonly used and reliable physical performance outcome measures for exercise interventions in older adults with mild to moderate ADRD. Further research is needed on optimal measures for individuals with severe ADRD.

CONCLUSIONS

The results of this review will aid clinicians and researchers in selecting reliable measures to evaluate physical performance outcomes in response to exercise interventions in older adults with ADRD.

Global cognition predicts the incidence of poor physical performance among older adults: A cross-national study

AIM

The relationship between physical performance and cognition is well established. However, findings on the relationship between global cognition and the incidence of functional disability has been inconsistent. Using data from the International Mobility in Aging Study, we investigated the relationship between baseline cognitive function and the incidence of poor physical performance 2 years later.

METHODS

A total of 1071 community-dwelling participants (aged 64-75 years) from four sites in Canada and Latin America, with a Short Physical Performance Battery score ≥9 at baseline (good performance) were included. We carried out two sets of analyses, measuring cognition with either the Leganés Cognitive Test or the Montreal Cognitive Assessment. We used three logistic regression models, controlling for either no confounders, sociodemographic confounders or sociodemographic and health confounders. The full model was also stratified by site. A score <9 on the Short Physical Performance Battery indicated poor physical performance.

RESULTS

In the fully adjusted model, each 1-point increase in the baseline Leganés Cognitive Test score (range 0-32) was associated with a 10% decrease in the odds of incidence of poor physical performance at the 2-year follow-up (P = 0.019). Likewise, each 1-point increase in the baseline Montreal Cognitive Assessment score (range 0-30) was associated with a 16% decrease in the odds of developing poor physical performance (P = 0.005). When stratified by site, the results were significant at the Latin American sites (P = 0.02), but not at the Canadian sites (P = 0.08).

CONCLUSIONS

Poor baseline cognition is associated with the incidence of poor physical performance in community-dwelling older adults. To prevent physical disability, interventions addressing both cognitive and physical performance are required. Geriatr Gerontol Int 2020; ••: ••-••.

Validity of Instrumented 360° Turn Test in Older Adults with Cognitive Impairment

AIMS

To examine concurrent and construct validity of inertial sensor 360°turn measures in relation with motion capture and mobility assessments in cognitively impaired older adults.

METHODS

Data was collected in 31 participants, mean age 85.2 (SD 5.2), during clockwise (CW) and counter clockwise (CCW) 360° turns using (1) APDM body-worn inertial sensors and (2) Qualisys 8-camera laboratory-based motion capture.

RESULTS

Absolute agreement between inertial sensor and motion capture measures was excellent for turn duration and turn peak velocity (ICC = 0.96-0.98). Strong to moderate correlations were present between inertial sensor turn measures and performance on the Timed Up and Go, Short Physical Performance Battery and 90-s Balance Test. ROC curve analysis of CCW 360° turn duration and turn peak velocity distinguished higher risk versus lower risk for mobility disability.

CONCLUSIONS

Inertial sensor 360° turn measures demonstrated concurrent and construct validity in relation to motion capture and mobility assessments.

The association of a novel cognitive frailty index and physical functioning in older at-risk adults

Objectives: Cognitive frailty is a state at the lower end of the continuum of cognitive resilience in which one is at elevated risk for cognitive impairment and dementia. Metrics of a newly developed Cognitive Frailty Index (CFI) were examined for their association with objective functional limitations.Methods: We used baseline data from 607 participants from the Baltimore Experience Corps Trial with measures on the CFI, a computerized Stroop test, and Short Physical Performance Battery (SPPB) score ≤9. Multivariable log-binomial regression models were used to evaluate the associations of CFI metrics (mean reaction time (RT) for total, first-half and second-half trials per condition) with the SPPB. Latent growth models were used to create additional CFI metrics of initial level (intercept) and change (slope) in RT across accurate trials by easy (Color-X) and difficult (Color-Word) conditions. Models were adjusted for race, sex, age, income, major morbidities, depressive symptoms, self-reported health, and Stroop interference (for Color-Word condition only).Results: All CFI RT metrics were associated with SPPB <9, yet latent growth model approaches were most informative. Initial levels of performance on easy (Risk Ratio, [RR] = 1.24; 95% Confidence Interval, [CI]: 1.03, 1.49) and difficult conditions (RR = 1.22; 95% CI: 1.05, 1.41), not rates of learning (slope) (RR = 1.08, 95% CI: 0.81, 1.45 and RR = 1.11, 95% CI: 0.96, 1.27 respectively), were associated with worse physical functioning.Conclusions: The association between the CFI and physical functioning demonstrates the interplay of cognitive frailty and worse objective mobility within a sociodemographic at-risk sample.

Differences in function and recovery profiles between patterns of multimorbidity among older medical patients the first year after an acute admission-An exploratory latent class analysis

INTRODUCTION

Multimorbidity is common among older people and may contribute to adverse health effects, such as functional limitations. It may help stratify rehabilitation of older medical patients, if we can identify differences in function under and after an acute medical admission, among patient with different patterns of multimorbidity.

AIM

To investigate differences in function and recovery profiles among older medical patients with different patterns of multimorbidity the first year after an acute admission.

METHODS

Longitudinal prospective cohort study of 369 medical patients (77.9 years, 62% women) acutely admitted to the Emergency Department. During the first 24 h after admission, one month and one year after discharge we assessed mobility level using the de Morton Mobility Index. At baseline and one-year we assessed handgrip strength, gait speed, Barthel20, and the New Mobility Score. Information about chronic conditions was collected by national registers. We used Latent Class Analysis to determine differences among patterns of multimorbidity based on 22 chronic conditions.

RESULTS

Four distinct patterns of multimorbidity were identified (Minimal chronic disease; Degenerative, lifestyle, and mental disorders; Neurological, functional and sensory disorders; and Metabolic, pulmonary and cardiovascular disorders). The "Neurological, functional and sensory disorders"-pattern showed significant lower function than the "Minimal chronic disease"-pattern in all outcome measures. There were no differences in recovery profile between patients in the four patterns.

CONCLUSION

The results support that patients with different patterns of multimorbidity among acutely hospitalized older medical patients differ in function, which suggests a differentiated approach towards treatment and rehabilitation warrants further studies.

Human-Robot-Environment Interaction Interface for Smart Walker Assisted Gait: AGoRA Walker

The constant growth of the population with mobility impairments has led to the development of several gait assistance devices. Among these, smart walkers have emerged to provide physical and cognitive interactions during rehabilitation and assistance therapies, by means of robotic and electronic technologies. In this sense, this paper presents the development and implementation of a human-robot-environment interface on a robotic platform that emulates a smart walker, the AGoRA Walker. The interface includes modules such as a navigation system, a human detection system, a safety rules system, a user interaction system, a social interaction system and a set of autonomous and shared control strategies. The interface was validated through several tests on healthy volunteers with no gait impairments. The platform performance and usability was assessed, finding natural and intuitive interaction over the implemented control strategies.

Incident Mobility Disability, Mild Cognitive Impairment, and Mortality in Community-Dwelling Older Adults

BACKGROUND/AIMS

Mobility disability and mild cognitive impairment (MCI) are common in aging and both are associated with risk of death. This study tested the hypothesis that risk of death differs by the order in which mobility disability and MCI occurred.

METHODS

One thousand two hundred and sixty-two community-dwelling older adults were unimpaired at baseline and followed annually. Mobility disability was based on measured gait speed, and MCI was based on cognitive performance tests. A multistate Cox model simultaneously examined incidences of mobility disability and MCI to determine whether the order of their occurrence is differentially associated with risk of death.

RESULTS

The average age was 75.3 years and 70% were female. While mobility disability occurred more frequently than incident MCI, the subsequent risk of death was higher in participants who developed MCI alone compared to those who developed mobility disability alone (hazard ratio [HR] 1.70, p = 0.018). Of the participants who initially developed mobility disability, about half subsequently developed MCI that doubled their risk of death (HR 2.17, p < 0.001). By contrast, over two-third who developed MCI subsequently developed mobility disability, which did not further increase their risk of death.

CONCLUSION

Mobility disability occurs more frequently in community-dwelling older adults, but MCI is more strongly associated with mortality.

Non-Aβ-Dependent Factors Associated with Global Cognitive and Physical Function in Alzheimer's Disease: A Pilot Multivariate Analysis

Recent literature highlights the importance of identifying factors associated with mild cognitive impairment (MCI) and Alzheimer’s Disease (AD). Actual validated biomarkers include neuroimaging and cerebrospinal fluid assessments; however, we investigated non-Aβ-dependent factors associated with dementia in 12 MCI and 30 AD patients. Patients were assessed for global cognitive function (Mini-Mental state examination—MMSE), physical function (Physical Performance Test—PPT), exercise capacity (6-min walking test—6MWT), maximal oxygen uptake (VO₂max), brain volume, vascular function (flow-mediated dilation—FMD), inflammatory status (tumor necrosis factor—α ,TNF- α, interleukin-6, -10 and -15) and neurotrophin receptors (p75NTR and Tropomyosin receptor kinase A -TrkA). Baseline multifactorial information was submitted to two separate backward stepwise regression analyses to identify the variables associated with cognitive and physical decline in demented patients. A multivariate regression was then applied to verify the stepwise regression. The results indicated that the combination of 6MWT and VO₂max was associated with both global cognitive and physical function (MMSE = 11.384 + (0.00599 × 6MWT) − (0.235 × VO₂max)); (PPT = 1.848 + (0.0264 × 6MWT) + (19.693 × VO₂max)). These results may offer important information that might help to identify specific targets for therapeutic strategies (NIH Clinical trial identification number NCT03034746).

Environmental predictors of objectively measured out-of-home time among older adults with cognitive decline

BACKGROUND

Older adults with cognitive decline are vulnerable to various health problems. Going out of home for longer time could be beneficial for their health. Identifying modifiable predictors is essential for developing effective strategies that would increase time spent out-of-home by older adults. This study examined social and physical environmental predictors of objectively measured out-of-home time spent among older adults with cognitive decline.

METHODS

This study was a secondary analysis of a randomized controlled trial (n = 147). Out-of-home time per day was measured by a Global Positioning System at baseline and 1-year follow-up. Baseline data of social environment (living alone, social network [Japanese version of the Lubben Social Network Scale]), objective physical environment (road network distance from each home address to nearest supermarket store, convenience store, and public transportation), and demographic factors (gender, age, education, driving status, fear of falling) were examined as potential predictors.

RESULTS

After adjusting main effects of allocation group, time of measures, and their interactive effect, a mixed model showed that younger age (p = 0.044), current driving status (p = 0.039), and stronger social network (p = 0.003) were predictors of out-of-home time. However, none of the physical environmental factors significantly predicted outdoor time.

CONCLUSIONS

The present study found that social network was a predictor of objectively measured out-of-home time among older adults with global cognitive decline. A sufficient social network might help increase out-of-home time among them. However, the influence of physical environment on out-of-home time might be small.

Association between the instrumented timed up and go test and cognitive function, fear of falling and quality of life in community dwelling people with dementia

OBJECTIVE

To explore relationships between the instrumented timed up and go test (iTUG) and the following risk factors for falls: cognitive functioning, fear of falling (FoF), and quality of life (QoL) in people with dementia.

METHODS

83 community-dwelling older adults with dementia (mean±sd age 78.00±7.96 years; 60.2% male) completed an interview to capture global cognition (Mini-Addenbrooke's Cognitive Evaluation), FoF (Iconographical Falls Efficacy Scale) and QoL (ICEpopCAPability measure for Older people). Participants completed an iTUG whilst wearing an inertial sensor on their trunk. Linear accelerations and rotational velocities demarcated sub-phases of the iTUG. Relationships were explored through correlations and regression modelling.

RESULTS

Cognition was related to duration of walking sub-phases and total time to complete iTUG (r=0.25-0.28) suggesting gait speed was related to cognition. FoF was most strongly related to turning velocity (r=0.39-0.44), but also to sit-to-stand, gait sub-phases and total time to complete iTUG. Sub-phases explained 27% of the variance in FoF. There were no correlations between iTUG and QoL.

CONCLUSIONS

Cognition and FoF were related to time to complete walking sub-phases but FoF was more closely related to turning velocity and standing acceleration. iTUG may offer unique insights into motor behaviour in people with dementia.

Correlates of Cognitive Impairment among Indian Urban Elders

BACKGROUND

Cognitive impairment among elderly is increasing owing to increases in life expectancy globally. The problem is multifactorial. The objective of the present paper was to study the correlates of cognitive impairment in an urban elderly population in India.

METHODS

A cross sectional study was conducted among 100 randomly selected urban elderly population. Data was collected upon household visits using a predesigned pretested questionnaire administered by a trained investigator. Measurements included cognitive function assessment using Mini Mental State Examination, depression assessment using Geriatric Depression Scale, blood pressure measurement and anthropometry. Cognitive impairment was defined at MMSE score <24. Logistic regression was done to identify independently associated factors with cognitive impairment.

RESULTS

Prevalence of cognitive impairment among elderly was 10%. Women had a higher prevalence than men. Higher age, no schooling, living single, lower weight, lower waist and hip ratios, difficulty in activities of daily living, poor self-reported health, bedridden and depression significantly associated with cognitive impairment. The independently associated factors upon logistic regression were increasing age, no schooling and bedridden status for past six months.

CONCLUSION

Although the current prevalence of cognitive impairment among Indian urban elderly is low, several associated factors exist in this population that may increase the burden in future. Geriatric health policy should address the modifiable risk factors to manage the problem of cognitive impairment and its consequent outcomes.

Tai Chi for older adults with chronic multisite pain: a randomized controlled pilot study

BACKGROUND

Chronic pain is associated with poorer cognition and mobility, and fall risk in older adults.

AIMS

To investigate the feasibility of a randomized controlled trial of mind-body exercise (Tai Chi) versus light physical exercise in older adults with multisite pain.

METHODS

Adults aged ≥ 65 years with multisite pain who reported falling in the past year or current use of an assistive device were recruited from Boston area communities. Participants were randomized to either a Tai Chi or a light physical exercise program, offered twice weekly for 12 weeks. The primary outcomes were feasibility and acceptability. Secondary outcomes included pain characteristics, cognition, physical function, gait mobility, fear of falling, and fall rate.

RESULTS

Of 176 adults screened, 85 were eligible, and 54 consented and enrolled (average age 75 ± 8 years; 96.30% white; 75.93% female). The dropout rate was 18% for Tai Chi and 12% for light physical exercise. For those completing the study, exercise class attendance rate was 76% for Tai Chi and 82% for light physical exercise. There were no significant group differences in most secondary outcomes. Tai Chi significantly lowered pain severity (4.58 ± 1.73 to 3.73 ± 1.79, p < 0.01) and pain interference (4.20 ± 2.53 to 3.16 ± 2.28, p < 0.05), reduced fear of falling (90.82 ± 9.59 to 96.84 ± 10.67, p < 0.05), and improved several single-task and dual-task gait variables, while light physical exercise did not change these measures.

DISCUSSION AND CONCLUSIONS

This study demonstrated the feasibility and acceptability of conducting a larger randomized controlled trial in older adults with multisite pain. Study findings and challenges encountered will inform future research.

Dietary patterns derived by factor analysis are associated with cognitive function among a middle-aged and elder Chinese population

The aim of this study was to assess the association of empirically derived dietary patterns with cognitive function among a middle-aged and elder Chinese population. This study comprised 1676 Chinese adults ≥45 years of age, who participated in a Health Survey and completed semi-quantitative food frequency questionnaire (FFQ) and cognitive screening test in the city of Linyi.We performed factor analysis using the principal component analysis method to identify the major dietary patterns. Binary logistic regression models were used to estimate odds ratio(OR) and 95% confidence interval(CI) for cognitive impairment according to quartiles of each dietary pattern score. Three dietary patterns were identified, namely traditional Chinese, Western-style and grains-fruits-vegetable patterns. A total of 362 participants (101 men and 261 women) were classified as cognitive impaired. After controlling for potential confounders, participants in the highest quartile of the Western-style pattern had a greater OR for incident cognitive impairment, compared to participants in the lowest quartile. Compared with the lowest quartile of grains-fruits-vegetable pattern, the highest quartile had a lower OR for incident cognitive impairment. Conclusions: Our findings demonstrate that the Western-style pattern is associated with an elevated risk and the grains-fruits-vegetables pattern is associated with a decreased risk of cognitive impairment.

Effectiveness of Transcutaneous Electrical Nerve Stimulation Energy in Older Adults: A Pilot Clinical Trial

OBJECTIVE

To evaluate the effectiveness of a transcutaneous electric nerve stimulation (TENS) device typically used for pain suppression (analgesia) during pressure injury (PI) healing, peripheral vascularization, and secondary pain in older adults with chronic PIs and cognitive impairment.

DESIGN AND SETTING

This pilot clinical trial followed patients from 6 nursing homes.

PATIENTS AND INTERVENTION

Twenty-two patients with PIs in the distal third of their lower limbs (7 men, 15 women) were included in this study. The control group completed standard wound care (SWC), whereas the experimental group received SWC and TENS. A total of 20 sessions were conducted for each group over 2 months, 3 times a week.

MAIN OUTCOME MEASURE

PI area, PI healing rate, blood flow, skin temperature, oxygen saturation, and level of pain at baseline and posttreatment.

MAIN RESULTS

Significant improvements were achieved in PI area (mean difference, 0.92; 95% confidence interval [CI], 0.15-1.67; P =.024), healing rate (3; 95% CI, 1-4.99; P =.009), skin temperature (1.82; 95% CI, 0.35-3.28; P =.021), and pain (1.44; 95% CI, 0.49-2.39; P =.008) in the experimental group, whereas none of the variables revealed a significant change in the control group.

CONCLUSIONS

The effect of local and spinal TENS combined with the SWC for PI produced a significant improvement in size, healing, skin temperature, and pain levels.

Impact of Multiple Chronic Conditions on Activity Limitations Among Older Mexican-American Care Recipients

INTRODUCTION

Older Mexican Americans are living longer with multiple chronic conditions (MCCs). This has placed greater demands on caregivers to assist with basic activities of daily living (ADL) or instrumental activities of daily living (IADL). To understand the needs of older Mexican-American care recipients, we examined the impact of MCC on ADL and IADL limitations.

METHODS

We analyzed data from 485 Mexican American care-receiving/caregiving dyads. Selected MCCs in the analysis were diabetes, hypertension, stroke, heart disease, arthritis, emphysema/chronic obstructive pulmonary disease, cognitive impairment, depression, and cancer. Care recipients were dichotomized as having 3 or more conditions or as having 2 or fewer conditions. Three comorbidity clusters were established on the basis of the most prevalent health conditions among participants with comorbid arthritis and hypertension. These clusters included arthritis and hypertension plus: diabetes (cluster 1), cognitive impairment (cluster 2), and heart disease (cluster 3).

RESULTS

Care recipients with 3 or more chronic conditions (n = 314) had higher odds of having mobility limitations (OR = 1.98; 95% CI, 1.34-2.94), self-care limitations (OR = 2.53; 95% CI, 1.70-3.81), >3 ADL limitations (OR = 2.00; 95% CI, 1.28-3.17), and >3 IADL limitations (OR = 1.88; 95% CI, 1.26-2.81). All clusters had increased odds of ADL and severe ADL limitations. Of care recipients in cluster 2, those with arthritis, hypertension, and cognitive impairment had significantly higher odds of mobility limitations (OR = 2.33; 95% CI, 1.05-5.24) than those with just arthritis and hypertension.

CONCLUSION

MCCs were associated with more ADL and IADL limitations among care recipients, especially for those with hypertension and arthritis plus diabetes, cognitive impairment, or heart disease. These findings can assist in developing programs to meet the needs of older Mexican-American care recipients.

15-Year Secular Trends in Cognitive Function Among Older Adults in the United States

Cognitive impairment is associated with various chronic diseases, including mobility limitation and early mortality. Thus, evaluating changes in cognition is of paramount public health interest. The purpose of this study was to evaluate secular trends in cognitive function among a representative sample of the U.S. older adult population. Data from the 1999-2000, 2001-2002, 2011-2012, and 2013-2014 National Health and Nutrition Examination Survey were utilized to identify an aggregate sample of adults 60+ years of age. The sample size across the four respective cycles was 1417, 1558, 1422, and 1592. Three cognitive assessments were employed, including the CERAD Word Learning subset (Consortium to Establish a Registry for Alzheimer's disease), the Animal Fluency test, and the Digit Symbol Substitution Test (DSST). For the entire sample and several subpopulations, DSST scores increased from 1999 to 2012 and then decreased in the 2013 to 2014 cycle. For all CERAD trials, there was evidence of increased CERAD performance from 2011-2012 to 2013-2014. No secular trends were observed for the Animal Fluency task across these cycles. Select cognitive parameters appear to be improving among U.S. older adults. Future work is needed to further explore secular trends in cognitive sustainability, and, as evidenced by our present study, cognitive enrichment over time.

Assessing robustness of hazard ratio estimates to outcome misclassification in longitudinal panel studies with application to Alzheimer's disease

Analyses of imperfectly assessed time to event outcomes give rise to biased hazard ratio estimates. This bias is a common challenge for studies of Alzheimer’s Disease (AD) because AD neuropathology can only be identified through brain autopsy and is therefore not available for most study participants. Clinical AD diagnosis, although more widely available, has imperfect sensitivity and specificity relative to AD neuropathology. In this study we present a sensitivity analysis approach using a bias-adjusted discrete proportional hazards model to quantify robustness of results to misclassification of a time to event outcome and apply this method to data from a longitudinal panel study of AD. Using data on 1,955 participants from the Adult Changes in Thought study we analyzed the association between average glucose level and AD neuropathology and conducted sensitivity analyses to explore how estimated hazard ratios varied according to AD classification accuracy. Unadjusted hazard ratios were closer to the null than estimates obtained under most scenarios for misclassification investigated. Confidence interval estimates from the unadjusted model were substantially underestimated compared to adjusted estimates. This study demonstrates the importance of exploring outcome misclassification in time to event analyses and provides an approach that can be undertaken without requiring validation data.

Impact of Osteoarthritis on Difficulty Walking: A Population-Based Study

OBJECTIVE

To assess the relationship of hip and knee osteoarthritis (OA) to walking difficulty.

METHODS

A population cohort ages ≤55 years recruited from 1996 to 1998 (n = 28,451) completed a standardized questionnaire assessing demographics, health conditions, joint symptoms, and functional limitations, including difficulty walking in the past 3 months. Survey data were linked to health administrative databases; self-report and administrative data were used to identify health conditions. Hip/knee OA was defined as self-reported swelling, pain, or stiffness in a hip or knee lasting ≥6 weeks in the past 3 months without an inflammatory arthritis diagnosis. Using multivariable logistic regression, we examined the determinants of walking difficulty and constructed a clinical nomogram.

RESULTS

A total of 18,490 cohort participants were eligible (mean age 68 years, 60% women), and 25% reported difficulty walking. Difficulty walking was significantly and independently associated with older age, female sex, body mass index, and several health conditions. Of the conditions examined, the likelihood of walking difficulty was greatest with hip and knee OA and increased with the number of hip/knee joints affected. The predicted probability of difficulty walking for a 60-year-old middle-income, normal-weight woman was 5-10% with no health conditions, 10-20% with diabetes mellitus and cardiovascular (CV) disease, 40% with OA in 2 hips/knees, 60-70% with diabetes mellitus, CV disease, and OA in 2 hips/knees, and 80% with diabetes mellitus, CV disease, and OA in all hips/knees.

CONCLUSION

In a population cohort, symptomatic hip/knee OA was the strongest contributor to walking difficulty. Given the importance of walking to engagement in physical activity for chronic disease management, greater attention to OA is warranted.

Cognitive Outcomes After Transcatheter Aortic Valve Implantation: A Metaanalysis

OBJECTIVES

To quantitatively summarize changes in cognitive performance in individuals with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI).

DESIGN

Metaanalysis.

PARTICIPANTS

Individuals undergoing TAVI (N = 1,065 (48.5% male) from 18 studies, average age ≥80).

MEASUREMENTS

The MEDLINE, EMBASE, and Cochrane Central databases were searched for original peer-reviewed reports assessing cognitive performance using standardized cognitive tests before and after TAVI. Data were extracted for cognitive scores before TAVI; perioperatively (within 7 days after TAVI); 1, 3, and 6 months after TAVI, and 12 to 34 months after TAVI (over the long term). Standardized mean differences (SMDs) were generated using random-effects models for changes in cognition at each time point. Metaregression analyses were conducted to assess the association between population and procedural characteristics and cognitive outcomes. Risk of bias was assessed.

RESULTS

There were no significant changes from baseline in perioperative cognitive performance (SMD = 0.05, 95% confidence interval (CI) = -0.08-0.18; z = 0.75, P = .46), although overall cognitive performance had improved significantly 1 month after TAVI (SMD = -0.33, 95% CI = -0.50 to -0.16; z = 3.83, P < .001). There were no differences in cognitive performance 3 and 6 months after TAVI or over the long term. Cognitive outcomes were not associated with any covariates in regression analyses.

CONCLUSION

Cognitive performance is preserved after TAVI, suggesting TAVI is not detrimental to cognition.