Measuring Physical Activity in Older Adults with and without Early Stage Alzheimer's Disease

Physical Activity Patterns Within Dementia Care Dyads

Previous research has explored the physical activity habits of people with dementia and their family carers separately, with little consideration of how physical habits are associated within dyads. In this observational study, we sought to explore the relationship between people with dementia and their carers' physical activity, at a group level and at a dyadic level. Twenty-six participant dyads (persons with dementia and their carer spouses) were asked to wear an accelerometer for 30 days continuously. Comparisons were made at a group level and a dyadic level. People with dementia did not participate in significantly more moderate to vigorous physical activity (M = 15.44 min/day; SD = 14.40) compared with carers (M = 17.95 min/day; SD = 17.01). Within dyads, there were moderately strong associations between daily moderate to vigorous physical activity (r = .48-.54), but not with overall activity levels (r = .24). Despite physical activity habits remaining relatively low within people with dementia and carers, respectively, moderate to vigorous physical activity levels appear to be correlated within dyads. Understanding mutual influence on physical activity levels within dyads is an important pathway to promote an active lifestyle.

How context links to best practice use in long-term care homes: a mixed methods study

BACKGROUND

Context (work environment) plays a crucial role in implementing evidence-based best practices within health care settings. Context is multi-faceted and its complex relationship with best practice use by care aides in long-term care (LTC) homes are understudied. This study used an innovative approach to investigate how context elements interrelate and influence best practice use by LTC care aides.

METHODS

In this secondary analysis study, we combined coincidence analysis (a configurational comparative method) and qualitative analysis to examine data collected through the Translating Research in Elder Care (TREC) program. Coincidence analysis of clinical microsystem (care unit)-level data aggregated from a survey of 1,506 care aides across 36 Canadian LTC homes identified configurations (paths) of context elements linked consistently to care aides' best practices use, measured with a scale of conceptual research use (CRU). Qualitative analysis of ethnographic case study data from 3 LTC homes (co-occurring with the survey) further informed interpretation of the configurations.

RESULTS

Three paths led to very high CRU at the care unit level: very high leadership; frequent use of educational materials; or a combination of very high social capital (teamwork) and frequent communication between care aides and clinical educators or specialists. Conversely, 2 paths led to very low CRU, consisting of 3 context elements related to unfavorable conditions in relationships, resources, and formal learning opportunities. Our qualitative analysis provided insights into how specific context elements served as facilitators or barriers for best practices. This qualitative exploration was especially helpful in understanding 2 of the paths, illustrating the pivotal role of leadership and the function of teamwork in mitigating the negative impact of time constraints.

CONCLUSIONS

Our study deepens understanding of the complex interrelationships between context elements and their impact on the implementation of best practices in LTC homes. The findings underscore that there is no singular, universal bundle of context-related elements that enhance or hinder best practice use in LTC homes.

Factors Associated With Physical Activity in Hospitalized Patients With Dementia

Older adults continue to spend little time engaged in physical activity when hospitalized. The purpose of this study was to (a) describe activity among hospitalized older adults with dementia and (b) identify the association between specific factors (gender, ambulation independence, comorbidities, race, and hospital setting) and their physical activity. This descriptive study utilized baseline data on the first 79 participants from the Function Focused Care for Acute Care using the Evidence Integration Triangle. Multiple linear regression models were run using accelerometry data from the first full day of hospitalization. The participants spent an average of 83.7% of their time being sedentary. Male gender, ambulation independence, and hospital setting (the hospital in which the patient was admitted) were associated with greater activity. This study reports on the limited time spent in activity for older adults with dementia when hospitalized and highlights patient profiles that are particularly vulnerable to sedentary behavior in the hospital setting.

A Telehealth Home-Based Exercise Program for Community-Dwelling Older People with Dementia in Indonesia: A Feasibility Study

(1) Background: This study aimed to evaluate the feasibility of a telehealth home-based exercise program for older people with dementia living in Indonesia with support from their informal carers. (2) Methods: Pre-post intervention single group study with three assessment time-points (baseline, 12 and 18 weeks). Participants with dementia underwent a 12-week physiotherapist-delivered telehealth exercise program, with informal carer supervision between supervised online sessions, and continued the exercises for a further six weeks without physiotherapist online supervision. (3) Results: Thirty dyads of older people with dementia and their informal carers were recruited; four (13.3%) withdrew across the 12-week intervention and one (3.3%) in the 6-week self-maintenance period. Median adherence was 84.1% (IQR [25, 75] = 17.1) during the 12-week intervention, and 66.7% (IQR [25, 75] = 16.7) in the self-maintenance period. No falls/adverse events were reported. Physical activity level, some aspects of function and disability, health-related benefits of exercise, exercise enjoyment and quality of life of older people with dementia improved significantly at 12 and 18 weeks. (4) Conclusions: The telehealth exercise program is feasible and safe and may have benefits for the health outcomes of community-living older people with dementia in Indonesia. Additional strategies are necessary to enhance longer-term adherence to the program.

The association of physical activity and behavioral and psychological symptoms among a sample of hospitalized older adults living with dementia

OBJECTIVES

The aims of this study were to: (1) describe the prevalence of behavioral and psychological symptoms of dementia in hospitalized older adults living with dementia and (2) examine the association of physical activity and behavioral and psychological symptoms of dementia among hospitalized older adults living with dementia, after controlling for covariates.

METHODS

Physical activity was measured using the Physical Activity Survey and behavioral and psychological symptoms of dementia were measured using the Neuropsychiatric Inventory. Descriptive analysis and multiple linear regressions were run using baseline data on 294 older adults with dementia hospitalized on general medical units from an ongoing study entitled Function Focused Care for Acute Care Using the Evidence Integration Triangle.

RESULTS

Participants performed an average of 7.92 (SD = 4.49) of 34 possible activities "in the last 24 h" prior to the Physical Activity Survey administration. A total of 132 participants (45.5%) had at least one behavioral and psychological symptom of dementia. We found that physical activity was not associated with behavioral and psychological symptoms of dementia (b = 0.01; p = 0.56), after controlling for covariates.

CONCLUSIONS

Although this study found no evidence of an association between physical activity and behavioral and psychological symptoms of dementia, evidence of physical activity did not exacerbate these behaviors. Thus, given the benefits of physical activity, it is important to continue to encourage patients living with dementia to engage in activity.

Physical Activity and its Influencing Factors in Community-Dwelling Older Adults With Dementia: A Path Analysis

Dementia is prevalent in worldwide, and increases the care burden and potential costs. Physical activity (PA) has been increasingly shown to be beneficial for them. This was a cross-sectional observational study aiming to investigate the status of PA among community-dwelling older adults with dementia in Beijing or Hangzhou, China, and verify the relationships between neuropsychiatric symptoms, activities of daily living (ADL), caregivers' fear of patients' falling and their PA using a path analysis approach. The level of PA among 216 included people with dementia was low. PA was related to the neuropsychiatric symptoms, with ADL and caregivers' fear of patients' falling have mediation roles. The findings indicated that person-centered strategies related to the management of these symptoms might be helpful to improve ADL, relieve caregivers' concerns about them falling and consequently foster positive participation in PA.

Barriers, motivators and facilitators of physical activity in people with dementia and their family carers in England: dyadic interviews

INTRODUCTION

Physical activity may have a number of physical and mental health benefits for people with dementia and their carers. However, there is limited evidence about factors that influence physical activity participation in these groups. This study therefore looks at the barriers, facilitators and motivators of physical activity in people with dementia, from both the perspective of the person with dementia and their carer.

METHOD

Thirty participants (15 sets of community-dwelling people with dementia and their family carers) were recruited from the South East of England. The participants took part in semi-structured dyadic interviews about their views of physical activity. Interviews were analysed using inductive thematic analysis at an individual level and comparisons were made between the groups.

RESULTS

Common motivator themes across persons with dementia and family carers were emotional and physical wellbeing, and social connectedness. Physical health was seen as a common barrier in both groups. Physical activity in the person with dementia was encouraged and supported by the family carer. For the carer, their caring role, and limited time acted as barriers to their participation.

CONCLUSION

Themes such as social connectedness, positive emotion and health were seen as key motivators to physical activity, which indicate that people with dementia and carers use physical activity as a means to maintain and improve their quality of life. Supporting family members to better facilitate such activities could encourage physical activity in people with dementia.

Physical Activity as a Predictor of Cognitive Decline in an Elderly Essential Tremor Cohort: A Prospective, Longitudinal Study

Background: Essential tremor (ET), one of the most common neurological diseases, is associated with cognitive impairment. Surprisingly, predictors of cognitive decline in ET remain largely unidentified, as longitudinal studies are rare. In the general population, however, lower physical activity has been linked to cognitive decline.

Objectives: To determine whether baseline physical activity level is a predictor of cognitive decline in ET.

Methods: One hundred and twenty-seven ET cases (78.1 ± 9.5 years, range = 55–95), enrolled in a prospective, longitudinal study of cognition. At baseline, each completed the Physical Activity Scale for the Elderly (PASE), a validated, self-rated assessment of physical activity. Cases underwent an extensive battery of motor-free neuropsychological testing at baseline, 1.5 years, and 3 years, which incorporated assessments of cognitive subdomains. Generalized estimating equations (GEEs) were used to assess the predictive utility of baseline physical activity for cognitive change.

Results: Mean follow-up was 2.9 ± 0.4 years (range = 1.3–3.5). In cross-sectional analyses using baseline data, lower physical activity was associated with lower overall cognitive function as well as lower cognitive scores in numerous cognitive domains (memory, language, executive function, visuospatial function and attention, all p < 0.05). In adjusted GEE models, lower baseline physical activity level significantly predicted overall cognitive decline over time (p=0.047), and declines in the subdomains of memory (p = 0.001) and executive function (p = 0.03).

Conclusions: We identified reduced physical activity as a predictor of greater cognitive decline in ET. The identification of risk factors often assists clinicians in determining which patients are at higher risk of cognitive decline over time. Interventional studies, to determine whether increasing physical activity could modify the risk of developing cognitive decline in ET, may be warranted.

The Association between Physical Activity and CAMDEX-DS Changes Prior to the Onset of Alzheimer's Disease in Down Syndrome

BACKGROUND

People with Down syndrome are at ultra-high risk of developing Alzheimer's dementia. At present, there are no preventative or curative treatments. Evidence from sporadic Alzheimer's disease literature suggests that lifestyle factors including physical activity may help maintain cognitive and functional skills and reduce dementia risk. Our study aimed to explore the association between regular exercise undertaken by participants with Down syndrome and changes in dementia-related domains of cognition and function. This was to consider whether physical activity may be a protective measure to delay cognitive decline and dementia in Down syndrome.

METHODS

Demographic, lifestyle, and health information was collected at baseline and at a two year follow up from 214 adults with Down syndrome without dementia, who also underwent assessment using the Cambridge Examination for Mental Disorders of Older People with Down Syndrome and Others with Intellectual Disabilities (CAMDEX-DS) and genetic analysis. Logistic regression models were used to examine the potential associations between decline in CAMDEX-DS domains and exercise whilst controlling for key variables.

RESULTS

At baseline, engaging in moderate intensity exercise was associated with a 47% reduced risk of everyday skills decline and engaging in high intensity exercise was associated with a 62% reduced risk of decline in personality and behaviour. At follow-up, high levels of exercise were associated with an 87% reduced risk of decline in personality and behaviour. Moderate intensity exercise at baseline was associated with a 62% reduction in risk of decline during the follow-up period in memory and orientation.

DISCUSSION

Based on our data it appears that regular moderate and high intensity exercise could reduce the risk of clinically detectable decline in a Down syndrome population with possible long-term benefits. People with Down syndrome may engage in less physical activity than their peers, and barriers remain which can prevent people with Down syndrome engaging in exercise. Our work highlights how important it is that people with Down syndrome are supported to be physically active, and to promote exercise as part of a healthy ageing plan. Clinical trials in this area would be justified to determine if engaging in exercise can lead to realistic improvements in maintaining functioning and delaying dementia onset in Down syndrome and to help develop guidance in this area.

Types of leisure time physical activities (LTPA) of community-dwelling persons who have been screened positive for dementia

Background

To (a) describe the pattern of leisure time physical activities (LTPA) in community-dwelling persons who have been screened positive for dementia and (b) determine the health-related and sociodemographic factors associated with LTPA.

Methods

Data of the general practitioner-based, randomized, controlled intervention trial, DelpHi-MV (Dementia: life- and person-centered help in Mecklenburg-Western Pomerania) were used. Patients aged 70 years or older, who lived at home and had a DemTect< 9 were informed about the study by their General practitioners and invited to participate. Data from 436 participants with complete baseline data were used. Standardized, computer-assisted assessments were made during face-to-face interviews at the participants’ homes.

Results

Two hundred thirty-eight patients (54.6%) carried out LTPA (men 58.4%, women 51.8%). Physically active patients mentioned one to two different activities; diversity of LTPA was higher for men than for women. The most-frequently mentioned types of activity were gardening (35.3%), cycling (24.1%) and mobility training (12.4%); there was only a statistically significant difference between men and women in cycling, χ²(1) = 21.47, p < .001. The odds of LTPA increased with increasing quality of life (OR = 2.41), lower impairments in activities of daily living (OR = 0.85), and living in a rural environment (OR = 2.02).

Conclusions

Our findings suggest that people who have been screened positive for dementia living in a rural area are more likely to be active than people living in an urban area. Following studies should investigate whether this difference has an effect on the progression of dementia.

Trial registration

ClinicalTrial.gov Identifier NCT01401582.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02201-1.

Physical activity in people with dementia attending farm-based dementia day care - a comparative actigraphy study

BACKGROUND

Despite public focus on the importance of physical activity and findings showing the benefits of such activity, research has shown that people with dementia are less physically active and have more sedentary behaviour compared to others in similar age groups. In Norway, there is a focus on day care services as a means to allow people with dementia to experience social, physical and cultural activities. Farm based services have been highlighted as an innovative and customized day care service, but little research has been done on physical activity and such services. This study therefor aims to investigate the potential of farm-based day care services as services that can promote physical activity for people with dementia.

METHODS

Actigraphy data from people with dementia attending farm-based day care services (n = 29) and people with dementia attending regular day care services (n = 107) was used to assess levels of physical activity in each group and to compare the two groups.

RESULTS

People attending farm-based day care had significantly higher levels of moderate activity, approximately 23 min each day, compared with persons attending ordinary day care (p = 0.048). Time spent in sedentary or light activity were similar for both groups. For the group attending farm-based day care services, days at the service, were significantly associated with less time spent in sedentary activity (p = 0.012) and more time spent in light (p < 0.001) and moderate activity (p = 0.032), and in taking more steps (p = 0.005) compared to days not at the service.

CONCLUSION

The findings indicate that participants in farm-based day care for people with dementia have higher levels of physical activity compared to ordinary day care and that farm-based day care increases levels of physical activity for its attendees. Farm based day care services has the potential to help their participants reach or maintain recommended levels of physical activity. Further research is needed to investigate what facilitates this increase in activity and how such knowledge could be used in all types of day care services.

Rate of Perceived Exertion and Cardiorespiratory Fitness in Older Adults with and without Alzheimer's Disease

Exercise has many benefits for physical and cognitive health in older adults, yet there are many barriers to exercise adherence in this population. Subjective perception of exercise difficulty, or rate of perceived exertion (RPE), may especially be a barrier to exercise in individuals with Alzheimer's disease (AD), due to changes in initiation and motivation that accompany changes in cognition and brain function. RPE is the most commonly used measure of subjective effort in exercise research, yet the relationship between RPE and objective fitness is not fully understood in older adults. A better understanding is needed to support initiation, engagement, and maintenance of exercise and determine the appropriateness for use of RPE as a measure in this population. Our study aimed to 1) evaluate the degree to which objective measures of cardiorespiratory fitness correlates with the most commonly used subjective measure of effort, RPE and 2) examine any difference in the relationship between objective cardiorespiratory fitness and RPE between individuals with and without AD. We explored these relationships during a graded exercise test. Objective fitness and subjective effort were negatively associated. Independent of cardiorespiratory fitness, older age, female gender, cognitive impairment, and use of heart medications predicted greater self-reported effort during exercise. Results are discussed in terms of social psychological phenomena and potential neuropsychological deficits leading to increased subjective feelings of effort. These findings establish that the RPE measure may not be appropriate and may even detract from effort during graded exercise testing among older adults with AD.

The Feasibility of Remotely Delivered Exercise Session in Adults With Alzheimer's Disease and Their Caregivers

Adults with Alzheimer's disease (AD) and their caregivers represent a segment of the population with low levels of moderate-intensity physical activity (MPA) and limited options for increasing MPA. The purpose of this study was to evaluate the feasibility of a group video conference approach for increasing MPA in adults with AD and their caregivers. Adults with AD and their caregivers attended 30-min group exercise sessions three times per week for 12 weeks. Exercise sessions and support sessions were delivered in their homes on a tablet computer over video conferencing software. Nine adults with AD/caregiver dyads enrolled, and seven completed the 12-week intervention. Adults with AD attended 77.3% of the group exercise sessions, and caregivers attended 79.2% of group exercise sessions. Weekly MPA increased in both adults with AD (49%) and caregivers (30%). Exercise delivered by group video conferencing is a feasible and potentially effective approach for increasing MPA in adults with AD and their caregivers.

Depressive symptoms as a barrier to engagement in physical activity in older adults with and without Alzheimer's disease

OBJECTIVES

Physical activity shows promise for reduced risk of Alzheimer's disease (AD) and protection against cognitive decline among individuals with and without AD. Older adults face many barriers to adoption of physically active lifestyles and people with AD face even further challenges. Physical activity is a promising non-pharmacological approach to improve depressive symptoms, but little is known about the impact of depressive symptoms as a potential barrier to engagement in physical activity. The present study aimed to investigate depressive symptoms as a potential barrier for participation in physical activity across a range of dementia severity.

METHOD

We used longitudinal structural equation modelling to investigate the bi-directional relationship between depressive symptoms and physical activity in 594 older adults with and without AD over a 2 year longitudinal follow up. Participants ranged from no cognitive impairment to moderately severe AD.

RESULTS

We found that depressive symptoms predicted reduced engagement in subsequent physical activity, but physical activity did not predict subsequent reductions in depressive symptoms.

CONCLUSION

We conclude that depressive symptoms may be an important barrier to engagement in physical activity that may be addressed in clinical practice and intervention research.

The Relationship Between the Stanford Leisure-Time Activity Categorical Item and the Godin Leisure-Time Exercise Questionnaire Among Rural Intervention Participants of Varying Health Literacy Status

BACKGROUND

A pragmatic, self-reported physical activity measure is needed for individuals of varying health literacy status.

METHODS

This study is a secondary analysis of a 6-month behavioral intervention for rural Appalachian adults developed using health literacy strategies. We examined the relationship and responsiveness of the Stanford Leisure-Time Activity Categorical Item (L-Cat) and adapted Godin Leisure-Time Exercise Questionnaire (GLTEQ) and determined if baseline health literacy status moderates intervention effects.

RESULTS

Of 301 enrolled participants, 289 completed the L-Cat at baseline and 212 at 6 months. Approximately 33% were low health literate and 43% reported annual income of ≤$14,999. There was high agreement (84.1%) between the L-Cat and adapted GLTEQ for classifying individuals as meeting physical activity recommendations with little differences by health literacy level (low literacy 80.4% and high literacy 85.9%). The primary source of incongruent classification was the adapted GLTEQ classified almost 20% of individuals as meeting recommendations, whereas the L-Cat classified them as not meeting recommendations. There were differences in responsiveness between measures, but baseline health literacy status did not moderate change in any L-Cat or adapted GLTEQ measures.

CONCLUSION

Implications and recommendations for using the L-Cat 2.3 and GLTEQ among individuals of varying health literacy status are discussed.

Daily Physical Activity Patterns During the Early Stage of Alzheimer's Disease

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease that results in severe disability. Very few studies have explored changes in daily physical activity patterns during early stages of AD when components of physical function and mobility may be preserved.

OBJECTIVE

Our study explored differences in daily physical activity profiles, independent of the effects of non-cognitive factors including physical function and age, among individuals with mild AD compared to controls.

METHODS

Patients with mild AD and controls (n = 92) recruited from the University of Kansas Alzheimer's Disease Center Registry, wore the Actigraph GT3X+ for seven days, and provided objective physical function (VO2 max) and mobility data. Using multivariate linear regression, we explored whether individuals with mild AD had different daily average and diurnal physical activity patterns compared to controls independent of non-cognitive factors that may affect physical activity, including physical function and mobility.

RESULTS

We found that mild AD was associated with less moderate-intensity physical activity (p < 0.05), lower peak activity (p < 0.01), and lower physical activity complexity (p < 0.05) particularly during the morning. Mild AD was not associated with greater sedentary activity or less lower-intensity physical activity across the day after adjusting for non-cognitive covariates.

CONCLUSIONS

These findings suggest that factors independent of physical capacity and mobility may drive declines in moderate-intensity physical activity, and not lower-intensity or sedentary activity, during the early stage of AD. This underscores the importance of a better mechanistic understanding of how cognitive decline and AD pathology impact physical activity. Findings emphasize the potential value of designing and testing time-of-day specific physical activity interventions targeting individuals in the early stages of AD, prior to significant declines in mobility and physical function.

Self-reported physical activity in essential tremor: Relationship with tremor, balance, and cognitive function

BACKGROUND

Physical inactivity may be the result of medical comorbidities. Inactivity itself may also lead to important health consequences, especially in older patients. Essential tremor (ET) patients may have a variety of physical and cognitive problems that could detrimentally impact on level of physical activity. Yet, to our knowledge, there have been no studies of physical activity in these patients.

METHODS

Self-reported physical activity was assessed using the Physical Activity Scale for the Elderly (PASE) in 100 ET cases (mean age 80.5years) enrolled in a clinical study. Additional clinical measures were the total tremor score, Montreal Cognitive Assessment (MOCA) score and number of steps taken off of the straight line during tandem gait (a measure of balance).

RESULTS

Lower PASE score was associated with older age, more tandem gait difficulty, higher total tremor score and lower MOCA score (all p<0.05). In a linear regression model that included total tremor score, MOCA score, number of steps off of the straight line during tandem gait, and age, higher total tremor score (p=0.046) and more steps off of the straight line during tandem gait (p=0.014) were independently associated with reductions in physical activity.

CONCLUSIONS

Several of the motor features of ET (tremor and imbalance) are independently associated with reductions in level of physical activity.

Feasibility of a Memory Clinic-Based Physical Activity Prescription Program

BACKGROUND

Effective programs for promoting physical activity are needed for those with cognitive impairment.

OBJECTIVE

To test the feasibility of mobile Health (mHealth) technology-supported physical activity prescription from a tertiary care memory clinic.

METHODS

This feasibility study was designed as a 16-week randomized, crossover trial of a physical activity prescription: 8 weeks of intervention, 8 weeks of baseline or maintenance phase data collection. We recruited 2 cohorts: 21 individuals with Alzheimer-related cognitive impairment (mean age 72.3 (5.2), 9 females), and 9 individuals with normal cognition (mean age 69.6 (5.8), 8 females). We gave each cohort an mHealth accelerometer-based physical activity prescription to double number of steps taken. Our primary outcomes were feasibility and safety. Our secondary outcomes were change in weekly steps taken, Dementia Quality of Life Scale, Self-efficacy Scale, 6-minute Walk, and mini-Physical Performance Test.

RESULTS

Set-up and use of the device was not a barrier to participation. However, only 62% of participants with cognitive impairment completed the intervention. The cohort with cognitive impairment did not change their weekly step count above Week 1. All participants in the cohort with normal cognition were able to set up and use their device and increased their weekly step count above Week 1. There were no differences between Week 1 and Week 8 for any secondary measures in either cohort.

CONCLUSIONS

Setup and daily use of mHealth technology appears to be feasible for a person with cognitive impairment with the help of a partner, but increasing daily step counts over 8 weeks was not achieved. Future work needs to assess alternative activity prescription goals or additional support for patients and their partners.

Intra-Individual Variability of Physical Activity in Older Adults With and Without Mild Alzheimer's Disease

Physical activity shows promise for protection against cognitive decline in older adults with and without Alzheimer's disease (AD). To better understand barriers to adoption of physical activity in this population, a clear understanding of daily and weekly activity patterns is needed. Most accelerometry studies report average physical activity over an entire wear period without considering the potential importance of the variability of physical activity. This study evaluated individual differences in the amount and intra-individual variability of physical activity and determined whether these differences could be predicted by AD status, day of wear, age, gender, education, and cardiorespiratory capacity. Physical activity was measured via accelerometry (Actigraph GT3X+) over one week in 86 older adults with and without AD (n = 33 and n = 53, respectively). Mixed-effects location-scale models were estimated to evaluate and predict individual differences in the amount and intra-individual variability of physical activity. Results indicated that compared to controls, participants with AD averaged 21% less activity, but averaged non-significantly greater intra-individual variability. Women and men averaged similar amounts of physical activity, but women were significantly less variable. The amount of physical activity differed significantly across days of wear. Increased cardiorespiratory capacity was associated with greater average amounts of physical activity. Investigation of individual differences in the amount and intra-individual variability of physical activity provided insight into differences by AD status, days of monitor wear, gender, and cardiovascular capacity. All individuals regardless of AD status were equally consistent in their physical activity, which may have been due to a highly sedentary sample and/or the early disease stage of those participants with AD. These results highlight the value of considering individual differences in both the amount and intra-individual variability of physical activity.

Older Adults with Dementia Are Sedentary for Most of the Day

PURPOSE

Self-reported data suggest that older adults with dementia are inactive. The purpose of the present study was to objectively assess the physical activity (PA) levels of community-dwelling and institutionalized ambulatory patients with dementia, and to compare with the PA levels of cognitive healthy older adults.

METHODS

We used actigraphy to assess the PA levels in institutionalized (n = 83, age: 83.0 ± 7.6, Mini-Mental-State Examination (MMSE): 15.5 ± 6.5) and community-dwelling dementia patients (n = 37, age: 77.3 ± 5.6, MMSE-score: 20.8 ± 4.8), and healthy older adults (n = 26, age: 79.5 ± 5.6, MMSE-score: 28.2 ± 1.6). We characterized PA levels based on the raw data and classified <100 counts/min as sedentary behavior.

RESULTS

Institutionalized dementia patients had the lowest daily PA levels (1.69 ± 1.33 counts/day), spent 72.1% of the day sedentary, and were most active between 8:00 and 9:00 am. Institutionalized vs. community-dwelling dementia patients had 23.5% lower daily PA levels (difference M = 0.52, p = .004) and spent 9.3% longer in sedentariness (difference M = 1.47, p = .032). Community-dwelling dementia patients spent 66.0% of the day sedentary and were most active between 9:00 to 10:00 am with a second peak between 14:00 to 15:00. Community-dwelling dementia patients vs healthy older adults' daily PA levels and sedentary time were 21.6% lower and 8.9% longer, respectively (difference M = 0.61, p = .007; difference M = 1.29, p = .078).

CONCLUSIONS

Institutionalized and community-dwelling dementia patients are sedentary for most of the day and the little PA they perform is of lower intensity compared to their healthy peers. Their highest PA peak is when they get out of bed in the morning. In addition, it seems that institutionalized living is associated with lower PA levels in dementia patients. These are the first results that objectively characterize institutionalized as well as community-dwelling dementia patients' PA levels and confirm that dementia patients are inactive.

Neighborhood Integration and Connectivity Predict Cognitive Performance and Decline

Objective: Neighborhood characteristics may be important for promoting walking, but little research has focused on older adults, especially those with cognitive impairment. We evaluated the role of neighborhood characteristics on cognitive function and decline over a 2-year period adjusting for measures of walking. Method: In a study of 64 older adults with and without mild Alzheimer’s disease (AD), we evaluated neighborhood integration and connectivity using geographical information systems data and space syntax analysis. In multiple regression analyses, we used these characteristics to predict 2-year declines in factor analytically derived cognitive scores (attention, verbal memory, mental status) adjusting for age, sex, education, and self-reported walking. Results: Neighborhood integration and connectivity predicted cognitive performance at baseline, and changes in cognitive performance over 2 years. The relationships between neighborhood characteristics and cognitive performance were not fully explained by self-reported walking. Discussion: Clearer definitions of specific neighborhood characteristics associated with walkability are needed to better understand the mechanisms by which neighborhoods may impact cognitive outcomes. These results have implications for measuring neighborhood characteristics, design and maintenance of living spaces, and interventions to increase walking among older adults. We offer suggestions for future research measuring neighborhood characteristics and cognitive function.

A systematic review of the evidence that brain structure is related to muscle structure and their relationship to brain and muscle function in humans over the lifecourse

BACKGROUND

An association between cognition and physical function has been shown to exist but the roles of muscle and brain structure in this relationship are not fully understood. A greater understanding of these relationships may lead to identification of the underlying mechanisms in this important area of research. This systematic review examines the evidence for whether: a) brain structure is related to muscle structure; b) brain structure is related to muscle function; and c) brain function is related to muscle structure in healthy children and adults.

METHODS

Medline, Embase, CINAHL and PsycINFO were searched on March 6th 2014. A grey literature search was performed using Google and Google Scholar. Hand searching through citations and references of relevant articles was also undertaken.

RESULTS

53 articles were included in the review; mean age of the subjects ranged from 8.8 to 85.5 years old. There is evidence of a positive association between both whole brain volume and white matter (WM) volume and muscle size. Total grey matter (GM) volume was not associated with muscle size but some areas of regional GM volume were associated with muscle size (right temporal pole and bilateral ventromedial prefrontal cortex). No evidence was found of a relationship between grip strength and whole brain volume however there was some evidence of a positive association with WM volume. Conversely, there is evidence that gait speed is positively associated with whole brain volume; this relationship may be driven by total WM volume or regional GM volumes, specifically the hippocampus. Markers of brain ageing, that is brain atrophy and greater accumulation of white matter hyperintensities (WMH), were associated with grip strength and gait speed. The location of WMH is important for gait speed; periventricular hyperintensities and brainstem WMH are associated with gait speed but subcortical WMH play less of a role. Cognitive function does not appear to be associated with muscle size.

CONCLUSION

There is evidence that brain structure is associated with muscle structure and function. Future studies need to follow these interactions longitudinally to understand potential causal relationships.