Performance-based physical function and future dementia in older people

Gait speed after mild stroke/transient ischemic attack was associated with long-term adverse outcomes: A cohort study

OBJECTIVE

The association between gait speed and adverse outcomes after stroke has not been fully illustrated. This study aimed to explore the association of gait speed on long-term outcomes in minor stroke or transient ischemic attack (TIA).

METHODS

We performed a longitudinal study with acute minor stroke or TIA based on a subgroup of the Third China National Stroke Registry data. The gait speed was evaluated using a 10-meter walking test at discharge and 3 months after the stroke onset. The primary outcomes were poor functional outcomes at 1 year, defined by a modified Rankin Score (mRS) of 2-6. Additional outcomes included all-cause death, ambulate dependency (mRS score 4-6), cognitive impairment (Montreal Cognitive Assessment <26), stroke recurrence, and composite vascular events.

RESULTS

The study sample included a total of 1542 stroke patients with a median age of 60 (53-68). At 1-year follow-up, 140 (9.20%) patients experienced poor functional outcomes. Faster gait speed at discharge was associated with lower incidence of poor functional outcome (OR = 0.89; 95% CI, 0.84-0.94), cognitive impairment (OR = 0.93; 95% CI, 0.89-0.96), ischemic stroke recurrence (HR = 0.92; 95% CI, 0.87-0.98), and composite vascular events (HR =0.94; 95% CI, 0.89-0.99) at 1 year. Faster gait speed at 3 months was associated with lower incidence of poor functional outcome (OR = 0.90; 95% CI, 0.85-0.95), ambulate dependency (OR = 0.86; 95% CI, 0.77-0.97), and cognitive impairment (OR = 0.92; 95% CI, 0.88-0.95) at 1 year.

INTERPRETATION

Our findings indicated that slow gait speed after minor stroke or TIA may be an independent predictor for long-term poor outcomes. Gait speed may be considered as a vital sign during follow-up in post-stroke patients.

Adult Physical Function Has Roots in Early Childhood Brain Function: A Five-Decade Cohort Study

OBJECTIVES

Tests of physical function are often thought to measure functioning that is (1) musculoskeletal, and (2) newly declining in adult life. In contrast, this study aimed to: (1) add to evidence that physical-function tests also measure brain function, and (2) test the novel hypothesis that adult physical function is associated with brain function beginning in early childhood. We investigated early childhood brain function and midlife physical function in the Dunedin Study, a 5-decade longitudinal birth cohort (n = 1,037).

METHODS

Brain function was measured at age 3 using 5 measures which formed a reliable composite (neurological examination, cognitive and motor tests, and temperament ratings). Physical function was measured at age 45 using 5 measures which formed a reliable composite (gait speed, step-in-place, chair stands, balance, and grip strength).

RESULTS

Children with worse age-3 brain function had worse midlife physical function as measured by the age-45 composite, even after controlling for childhood socioeconomic status (β: 0.23; 95% CI: 0.16 to 0.30; p < .001). Worse age-3 brain function significantly predicted slower gait speed, fewer steps-in-place and chair-stands, worse balance, and weaker grip strength.

DISCUSSION

Children with poorer brain function were more likely to have poorer physical-function scores as adults. In addition to indicating recent musculoskeletal decline, physical-function tests may also provide indications of lifelong, integrated brain-body health. By reconceptualizing the meaning of physical-function scores, clinicians can orient the use of physical-function tests in a more holistic approach to health care.

Fluid Cognition Among Individuals With Systemic Lupus Erythematosus

OBJECTIVE

We sought to describe fluid cognition and its correlates among individuals with systemic lupus erythematosus (SLE).

METHODS

Participants (n = 199) were recruited from a population-based cohort for a single study visit (October 2019 to May 2022). Fluid cognition was measured via the National Institutes of Health Toolbox Fluid Cognition Battery (including episodic memory, working memory, attention and inhibitory control, processing speed, and cognitive flexibility domains) and expressed as age-corrected standard scores (mean 100, SD 15). Potential impairment was defined as a standard score >1.5 SD below the mean. Descriptive statistics were calculated and associations of various participant characteristics with the potential fluid cognition impairment were assessed with multivariable logistic regression.

RESULTS

Participants' mean age was 46.1 years; most were female (87.4%), Black (86.4%), and non-Hispanic (95.0%). The mean overall fluid cognition score was 87.2; of the individual domains, the participants' mean score was lowest on attention and inhibitory control (82.0). Working status (odds ratio [OR] 0.30, 95% confidence interval [CI] 0.14-0.64) and higher self-reported physical functioning (OR 0.46, 95% CI 0.28-0.75) and physical performance (OR 0.72, 95% CI 0.59-0.87) were associated with lower odds of fluid cognition impairment; lower educational attainment was associated with higher odds (OR 3.82, 95% CI 1.67-8.75). Self-reported forgetfulness, neuropsychiatric damage, and depressive symptoms were not statistically significantly associated with potential impairment.

CONCLUSION

Fluid cognition and, particularly, attention and inhibitory control were low in those with SLE relative to the general US population. Working status, higher physical functioning and performance, and higher educational attainment were associated with lower prevalence of potential impairment. Future work is needed to develop and implement interventions to help support cognition in individuals with SLE.

Balance, Strength, and Risk of Dementia: Findings From the Health and Retirement Study and the English Longitudinal Study of Ageing

BACKGROUND

Slow gait speed has been consistently associated with an increased risk of dementia. This study examined whether measures of balance and lower limb strength are similarly related to the risk of developing dementia.

METHODS

Participants from the Health and Retirement Study (HRS, N = 5 658, mean age = 73.23, standard deviation [SD] = 6.22) and the English Longitudinal Study of Ageing (ELSA, N = 3667, mean age = 69.90, SD = 7.02) completed measures of gait speed, semi-tandem balance, chair stand (ELSA only), and cognitive status at baseline. Cognitive status was assessed over up to 15 years.

RESULTS

Baseline slower gait speed (hazard ratio [HR]HRS = 1.52, 95% confidence interval [CI] = 1.32-1.75, p < .001; HRELSA = 1.73, 95% CI = 1.37-2.18, p < .001); and balance impairment (HRHRS = 1.58, 95% CI = 1.26-1.96, p < .001; HRELSA = 1.97, 95% CI = 1.24-3.14, p < .01) were related to a higher risk of incident dementia, adjusting for demographic factors. The combination of slower gait and impaired balance was associated with a two-to-three times higher risk of dementia in HRS and ELSA. Worse performance on the chair stand at baseline was associated with a higher risk of dementia in ELSA (HR = 1.56, 95% CI = 1.23-1.99, p < .001). All performance measures remained significant when entered simultaneously and accounted for obesity, diabetes, blood pressure, physical activity, smoking, and depressive symptoms. There was little evidence that age, sex, or APOE ε4 moderated the association.

CONCLUSIONS

Similar to gait speed, measures of balance and strength are associated with a higher risk of incident dementia. The findings have implications for clinical practice, given that these routinely used geriatric assessment tools are similarly related to dementia risk.

Exploring symptom clusters in mild cognitive impairment and dementia with the NIH Toolbox

OBJECTIVE

Symptom clustering research provides a unique opportunity for understanding complex medical conditions. The objective of this study was to apply a variable-centered analytic approach to understand how symptoms may cluster together, within and across domains of functioning in mild cognitive impairment (MCI) and dementia, to better understand these conditions and potential etiological, prevention, and intervention considerations.

METHOD

Cognitive, motor, sensory, emotional, and social measures from the NIH Toolbox were analyzed using exploratory factor analysis (EFA) from a dataset of 165 individuals with a research diagnosis of either amnestic MCI or dementia of the Alzheimer's type.

RESULTS

The six-factor EFA solution described here primarily replicated the intended structure of the NIH Toolbox with a few deviations, notably sensory and motor scores loading onto factors with measures of cognition, emotional, and social health. These findings suggest the presence of cross-domain symptom clusters in these populations. In particular, negative affect, stress, loneliness, and pain formed one unique symptom cluster that bridged the NIH Toolbox domains of physical, social, and emotional health. Olfaction and dexterity formed a second unique cluster with measures of executive functioning, working memory, episodic memory, and processing speed. A third novel cluster was detected for mobility, strength, and vision, which was considered to reflect a physical functioning factor. Somewhat unexpectedly, the hearing test included did not load strongly onto any factor.

CONCLUSION

This research presents a preliminary effort to detect symptom clusters in amnestic MCI and dementia using an existing dataset of outcome measures from the NIH Toolbox.

Early detection of diseases causing dementia using digital navigation and gait measures: A systematic review of evidence

Wearable digital technologies capable of measuring everyday behaviors could improve the early detection of dementia-causing diseases. We conducted two systematic reviews following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines to establish the evidence base for measuring navigation and gait, two everyday behaviors affected early in AD and non-AD disorders and not adequately measured in current practice. PubMed and Web of Science databases were searched for studies on asymptomatic and early-stage symptomatic individuals at risk of dementia, with the Newcastle-Ottawa Scale used to assess bias and evaluate methodological quality. Of 316 navigation and 2086 gait records identified, 27 and 83, respectively, were included in the final sample. We highlight several measures that may identify at-risk individuals, whose quantifiability with different devices mitigates the risk of future technological obsolescence. Beyond navigation and gait, this review also provides the framework for evaluating the evidence base for future digital measures of behaviors considered for early disease detection.

Traffic-related air pollution and dementia incidence in the Adult Changes in Thought Study

BACKGROUND

While epidemiologic evidence links higher levels of exposure to fine particulate matter (PM2.5) to decreased cognitive function, fewer studies have investigated links with traffic-related air pollution (TRAP), and none have examined ultrafine particles (UFP, ≤100 nm) and late-life dementia incidence.

OBJECTIVE

To evaluate associations between TRAP exposures (UFP, black carbon [BC], and nitrogen dioxide [NO2]) and late-life dementia incidence.

METHODS

We ascertained dementia incidence in the Seattle-based Adult Changes in Thought (ACT) prospective cohort study (beginning in 1994) and assessed ten-year average TRAP exposures for each participant based on prediction models derived from an extensive mobile monitoring campaign. We applied Cox proportional hazards models to investigate TRAP exposure and dementia incidence using age as the time axis and further adjusting for sex, self-reported race, calendar year, education, socioeconomic status, PM2.5, and APOE genotype. We ran sensitivity analyses where we did not adjust for PM2.5 and other sensitivity and secondary analyses where we adjusted for multiple pollutants, applied alternative exposure models (including total and size-specific UFP), modified the adjustment covariates, used calendar year as the time axis, assessed different exposure periods, dementia subtypes, and others.

RESULTS

We identified 1,041 incident all-cause dementia cases in 4,283 participants over 37,102 person-years of follow-up. We did not find evidence of a greater hazard of late-life dementia incidence with elevated levels of long-term TRAP exposures. The estimated hazard ratio of all-cause dementia was 0.98 (95 % CI: 0.92-1.05) for every 2000 pt/cm3 increment in UFP, 0.95 (0.89-1.01) for every 100 ng/m3 increment in BC, and 0.96 (0.91-1.02) for every 2 ppb increment in NO2. These findings were consistent across sensitivity and secondary analyses.

DISCUSSION

We did not find evidence of a greater hazard of late-life dementia risk with elevated long-term TRAP exposures in this population-based prospective cohort study.

Association between serum lipid levels and lower-extremity functions in older adults with and without Alzheimer's dementia in South Korea: A cross-sectional analysis

PURPOSE

Older adults with Alzheimer's dementia (AD) experience lower-extremity dysfunction. High serum lipid levels are a risk factor for AD. We investigated the association between serum lipid levels and lower-extremity function in older individuals with and without AD.

METHODS

In this cross-sectional study, we enrolled 33,185 senior citizens (aged 66 years) who participated in the National Geriatric Screening Program, sampled from the Korean National Health Insurance Service-National Health Screening Cohort Database, between 2009 and 2015. Participants were dichotomized into 1) an AD group comprising individuals with the International Classification of Diseases, Tenth Revision, diagnostic codes F00, F00.0-F00.9, and G30, G30.0-G30.9; and 2) a control group comprising individuals without AD. Differences in the Timed Up and Go and One-Leg Standing results among the three levels (low, moderate, and high) of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol were evaluated between the groups. Logistic regression analysis was performed to estimate the odds of gait disorder considering clinical and lifestyle variables.

RESULTS

In participants with low LDL-C levels, increased LDL-C levels correlated with higher gait speed. In the AD group, balancing time with eyes open (BT-EO) was inversely correlated with TG levels in participants with low TG levels. In the control group, BT-EO was negatively correlated with TC levels in participants with low TC levels.

CONCLUSION

Serum lipid levels were significantly correlated with lower-extremity function in participants with and without AD but not with gait disorder in participants with AD.

Constricting Life Space and Likelihood of Neurodegenerative Disease in Community-Dwelling Older Men

Importance

Life space is a measure of the frequency, range, and independence of movement through the environment. There is increasing interest in life space as a holistic measure of function in older adults, but the association between change in life space and incident neurodegenerative disease is unknown.

Objective

To evaluate the association between change in life space and cognitive decline or incident neurodegenerative disease over 7 years among community-dwelling older men.

Design, Setting, and Participants

In this cohort study, logistic regression analyses were used to examine the association of baseline and change in life space with change in cognition unadjusted and adjusted for demographics, cardiovascular risk factors, depression, gait speed, and physical activity. Mixed linear effects models were used to evaluate the association between change in life space and change in cognition. Men were recruited from 6 US sites to participate in a prospective, community-based cohort study of aging and followed-up from 2007 to 2014. Individuals with prevalent dementia or Parkinson disease (PD) at baseline were excluded. Data were analyzed from May 2022 to September 2023.

Exposure

Life space, assessed using the University of Alabama at Birmingham Life Space Assessment and divided into tertiles.

Main Outcomes and Measures

Participants completed the Modified Mini-Mental State (3MS) Test, and Trail-Making Test Part B at baseline and 7 years later. At follow-up, participants were asked about a new physician diagnosis of dementia and PD.

Results

A total of 1684 men (mean [SD] age, 77.1 [4.2] years) were recruited and over 7 years of follow-up, 80 men (4.8%) developed dementia and 23 men (1.4%) developed PD. Mean (SD) life space score was 92.9 (18.7) points and mean (SD) change was -9.9 (22.3) points over follow up. In the adjusted model, each 1-SD decrement in life space was associated with increased odds of dementia (odds ratio [OR], 1.59; 95% CI, 1.28-1.98) but not PD (OR, 1.48; 95% CI, 0.97-2.25). For each 1-SD decrement in life space, men worsened by 20.6 (95% CI, 19.8-21.1) seconds in their Trails B score (P < .001) and declined by 1.2 (95% CI, 1.0-1.3) points in their 3MS score (P < .001) over 7 years.

Conclusions and Relevance

In this study of 1684 men followed up over 7 years, change in life space was associated with faster cognitive decline and increased likelihood of neurodegenerative illness. Future studies should examine the role of clinician assessments or wearable electronics in tracking life space in older adults at risk of cognitive decline and neurodegenerative illness.

Association Between the Loss of Gait Harmony and Cognitive Impairment: Cross-Sectional Study

BACKGROUND

Functional limitations and disabilities have been associated with a decrease in cognitive function due to increasing age. Gait performance and cognitive function have been associated with gait variability in executive function, the phase domain in memory, and gait abnormalities in cognitive decline.

OBJECTIVE

Our study aimed to investigate whether gait harmony was associated with cognitive function in the older adult population. Moreover, we aimed to investigate whether gait harmony was associated with cognitive function and explore each cognitive function in a specific harmonic state.

METHODS

The study population included 510 adults aged ≥60 years who visited the Department of Neurology at the Veterans Health Service Medical Center, Seoul, South Korea. Gait data were collected using a 3D motion capture device with a wireless inertial measurement unit system. For cognitive function assessments, we used the Seoul Neuropsychological Screening Battery-Core test, which evaluates the level of cognitive function or impairment in 5 cognitive domains.

RESULTS

In general, the association between the Seoul Neuropsychological Screening Battery-Core tests and the stance-to-swing ratio in the >1.63 ratio group yielded lower β coefficients than those in the 1.50-1.63 ratio group. After adjustment for confounders, the odds ratio (OR) for the Digit Symbol Coding test (adjusted OR 0.42, 95% CI 0.20-0.88) and the Korean version of the Color Word Stroop Test: 60 seconds (adjusted OR 0.51, 95% CI 0.29-0.89) for frontal and executive function were significantly lower for the >1.63 ratio group than the reference group.

CONCLUSIONS

Our findings suggest that the gait phase ratio is a valuable indicator of walking deficits and may also be associated with cognitive impairment in older adults.

Association between upper limb movements during drumming and cognition in older adults with cognitive impairment and dementia at a nursing home: a pilot study

Background

Despite the association between motor dysfunction and dementia, quantitative assessment of dementia-related specific motor dysfunction in patients with severe dementia is difficult. Thus, this study aimed to develop a new method to measure upper limb motor function in people with dementia.

Methods

We examined the relationship between dementia severity and dementia-related specific motor dysfunction using the Mini-Mental State Examination (MMSE), a dementia screening test. Participants comprised 16 nursing home residents with a mean age of 86 years and MMSE score of 14.56 (range, 1-23) Points. Participants were seated in a circle and instructed to play a drum that was placed in their lap using mallets (drumsticks) in their dominant hand. Acceleration and gyroscopic sensors were attached to their wrists to collect data on arm movements while drumming. Upper limb motor characteristics were confirmed by recording acceleration and arm movement during drumming and analyzing the correlation with handgrip strength.

Results

Handgrip strength was correlated with arm elevation angle during drumming. The arm elevation angle displayed a significant regression equation with the MMSE score and showed the best regression equation along with handgrip strength (adjusted R² = 0.6035, p = 0.0009).

Conclusion

We developed a new method using drums to measure upper limb motor function in people with dementia. We also verified that the average arm elevation angle during drumming could predict cognitive dysfunction. This system may be used to monitor people with dementia in a simple and safe way.

Does physical activity attenuate the association between ambient PM2.5 and physical function?

BACKGROUND

Physical function (PF), such as muscle strength, performing daily activities, has gradually declined with the increase of age, causing the occurrence of disability and diseases burden. Air pollution exposure and physical activity (PA) were both linked to PF. We aimed to explore the individual and joint effects of particulate matter <2.5 μm (PM_2.5) and PA on PF.

METHODS

A total of 4537 participants and 12,011 observations aged ≥45 years old from the China Health and Retirement Longitudinal Study (CHARLS) cohort from 2011 to 2015 were included into the study. PF was assessed by a combined score of four tests, including grip strength, walking speed, sense of balance, and chair standing tests. Air pollution exposure data was from The ChinaHighAirPollutants (CHAP) dataset. The annual PM_2.5 exposure for each individual was estimated based on county-level resident addresses. We estimated the volume of moderate-to-vigorous physical activity (MVPA) by quoting metabolic equivalent (MET). Multivariate linear model was conducted for baseline analysis, and linear mixed model with random participant intercepts was constructed for cohort longitudinal analysis.

RESULTS

PM_2.5 was negatively associated with PF, while PA was positively associated with PF in baseline analysis. In cohort longitudinal analysis, a 10 μg/m³ increase in PM_2.5 was associated to a 0.025 point (95 % CI: -0.047, -0.003) decrease in PF score, and a 10-MET-h/week increase in PA was related to a 0.004 point (95 % CI: 0.001, 0.008) increase in PF score. The association between PM_2.5 and PF decreased by increased PA intensity, and PA reversed the detrimental effects between PM_2.5 and PF.

CONCLUSION

PA attenuated the association of air pollution with PF at both high and low levels of air pollution, implying that PA may be an effective behavior to reduce the adverse effects of poor air quality on PF.

Short-term associations between warm-season ambient temperature and emergency department visits for Alzheimer's disease and related dementia in five US states

BACKGROUND

Ambient temperatures are projected to increase in the future due to climate change. Alzheimer's disease (AD) and Alzheimer's disease-related dementia (ADRD) affect millions of individuals and represent substantial health burdens in the US. High temperature may be a risk factor for AD/ADRD outcomes with several recent studies reporting associations between temperature and AD mortality. However, the link between heat and AD morbidity is poorly understood.

METHODS

We examined short-term associations between warm-season daily ambient temperature and AD/ADRD emergency department (ED) visits for individuals aged 45 years or above during the warm season (May to October) for up to 14 years (2005-2018) in five US states: California, Missouri, North Carolina, New Jersey, and New York. Daily ZIP code-level maximum, average and minimum temperature exposures were derived from 1 km gridded Daymet products. Associations are assessed using a time-stratified case-crossover design using conditional logistic regression.

RESULTS

We found consistent positive short-term effects of ambient temperature among 3.4 million AD/ADRD ED visits across five states. An increase of the 3-day cumulative temperature exposure of daily average temperature from the 50th to the 95th percentile was associated with a pooled odds ratio of 1.042 (95% CI: 1.034, 1.051) for AD/ADRD ED visits. We observed evidence of the association being stronger for patients 65-74 years of age and for ED visits that led to hospital admissions. Temperature associations were also stronger among AD/ADRD ED visits compared to ED visits for other reasons, particularly among patients aged 65-74 years.

CONCLUSION

People with AD/ADRD may represent a vulnerable population affected by short-term exposure to high temperature. Our results support the development of targeted strategies to reduce heat-related AD/ADRD morbidity in the context of global warming.

Capturing Measures That Matter: The Potential Value of Digital Measures of Physical Behavior for Alzheimer's Disease Drug Development

Alzheimer's disease (AD) is a devastating neurodegenerative disease and the primary cause of dementia worldwide. Despite the magnitude of AD's impact on patients, caregivers, and society, nearly all AD clinical trials fail. A potential contributor to this high rate of failure is that established clinical outcome assessments fail to capture subtle clinical changes, entail high burden for patients and their caregivers, and ineffectively address the aspects of health deemed important by patients and their caregivers. AD progression is associated with widespread changes in physical behavior that have impacts on the ability to function independently, which is a meaningful aspect of health for patients with AD and important for diagnosis. However, established assessments of functional independence remain underutilized in AD clinical trials and are limited by subjective biases and ceiling effects. Digital measures of real-world physical behavior assessed passively, continuously, and remotely using digital health technologies have the potential to address some of these limitations and to capture aspects of functional independence in patients with AD. In particular, measures of real-world gait, physical activity, and life-space mobility captured with wearable sensors may offer value. Additional research is needed to understand the validity, feasibility, and acceptability of these measures in AD clinical research.

Predictive Validity of Different Walking Measures to Identify the Incident Long-Term Care Needs in Older Adults

OBJECTIVES

A comfortable walking speed is a suitable measurement of functional status in older adults. In addition to assessing their comfortable walking speed, two complex walking tests were administered to a cohort of older people, assuming that these tests would be a more sensitive predictor of the incident long-term care needs than comfortable walking speed.

DESIGN

A prospective observational study was conducted to collect data.

SETTING AND PARTICIPANTS

Among the initial 5,563 community-dwelling independent older adults (aged ≥ 65 years), 935 were excluded and the data of 4,628 (mean age, 73.9 ± 5.5 years, 65-94 years; 2,052 men, 2,576 women) older adults were finally analyzed.

METHODS

Three walking tasks were administered: comfortable, complicated balance, and Go-stop walking. Complicated balance walking was measured under comfortable walking conditions, with participants having to walk with their hands crossed at the shoulder joint at 90°. For the Go-stop walking test, the time taken to walk 2 meters was measured using a stopwatch. For two years following baseline assessments, participants received monthly follow-ups for incident certification of the need for care under the long-term care insurance (LTCI) system.

RESULTS

Low performance in comfortable, complicated balance, and Go-stop walking were 29.8%, 37.7%, and 35.1%, respectively. During the 24-month follow-up period, 246 participants (5.3%) required LTCI certification. The Youden Index was used to determine the cut-points of the incident long-term care needs in the comfortable, complicated balance, and Go-stop walking conditions, which were 1.055 m/s, 0.936 m/s, and 3.205 seconds, respectively. Participants classified as exhibiting low performance included 1,381 (29.8%) under comfortable walking, 1,746 (37.7%) under complicated balance walking, and 1,623 (35.1%) under the Go-stop walking tests. The C-indices of the comfortable, complicated balance, and Go-stop walking tests were 0.72 (95% confidence interval (CI) 0.69-0.76), 0.71 (95% CI 0.67-0.74), and 0.65 (95% CI 0.61-0.69), respectively. Cox proportional hazards regression model revealed significant relationships between the incident long-term care needs and the comfortable (hazard ratio (HR) 2.14, 95% CI 1.62-2.84), complicated balance (1.81, 1.36-2.41), and Go-stop (1.46, 1.12-1.91) walking conditions.

CONCLUSIONS AND IMPLICATIONS

The findings suggest that slow walking speed has a considerably greater impact on the incident long-term care needs in older adults. However, the complex walking task did not improve the predictive performance. Comfortable walking speed tests, which can easily be measured to predict the future incident long-term care needs, are effective tools in community health promotion and primary care.

Prospective Associations of Plasma Growth Differentiation Factor 15 With Physical Performance and Cognitive Functions in Older Adults

BACKGROUND

Growth differentiation factor 15 (GDF15) has been associated with several age-related disorders, but its associations with functional abilities in community-dwelling older adults are not well studied.

METHODS

The study was a secondary analysis of 1 096 community-dwelling older adults (aged 69-94 years) recruited from the Multidomain Alzheimer's Preventive Trial. Plasma GDF15 was measured 1 year after participants' enrollment. Annual data of physical performance (grip strength and Short Physical Performance Battery [SPPB]) and global cognitive functions (Mini-Mental State Examination [MMSE] and a composite cognitive score) were measured for 4 years. Adjusted mixed-effects linear models were performed for cross-sectional and longitudinal association analyses.

RESULTS

A higher GDF15 was cross-sectionally associated with a weaker grip strength (β = -1.1E-03, 95% CI [-2.0E-03, -1.5E-04]), a lower SPPB score (β = -3.1E-04, 95% CI [-5.4E-04, -9.0E-05]), and worse cognitive functions (β = -2.4E-04, 95% CI [-3.3E-04, -1.6E-04] for composite cognitive score; β = -4.0E-04, 95% CI [-6.4E-04, -1.6E-04] for MMSE). Participants with higher GDF15 demonstrated greater longitudinal declines in SPPB (β = -1.0E-04, 95% CI [-1.7E-04, -2.0E-05]) and composite cognitive score (β = -2.0E-05, 95% CI [-4.0E-05, -3.6E-06]). The optimal initial GDF15 cutoff values for identifying participants with minimal clinically significant decline after 1 year were 2 189 pg/mL for SPPB (AUC: 0.580) and 2 330 pg/mL for composite cognitive score (AUC: 0.587).

CONCLUSIONS

Plasma GDF15 is cross-sectionally and longitudinally associated with lower-limb physical performance and global cognitive function in older adults. Circulating GDF15 alone has a limited capacity of discriminating older adults who will develop clinically significant functional declines.

CLINICAL TRIAL REGISTRATION

NCT00672685.

Effect of Electrical Muscle Stimulation and Resistance Exercise Intervention on Physical and Brain Function in Middle-Aged and Older Women

This study investigated the effectiveness of electrical muscle stimulation (EMS) with resistance exercise training (ERT) and resistance exercise training (RT) on physical and brain function in middle-aged and older women. Method: Forty-eight participants were randomly allocated into three groups: (i) ERT (n = 16), (ii) RT (n = 16), and (iii) control group (n = 16). The intervention session was 50 min long and performed three times/week for four weeks. The ERT group performed quadriceps setting, straight leg raises, and ankle pump exercises while constantly receiving EMS on their quadriceps muscle on both legs. The RT group performed the same exercise without EMS. Physical function was measured using skeletal muscle mass index (SMI), handgrip strength, gait speed, five times sit-to-stand test (FTSS) and timed up-and-go test (TUG). Brain function was assessed with electroencephalogram measurement of whole brain activity. Results: After four-week intervention, significant improvements were observed in SMI (p < 0.01), phase angle (p < 0.05), and gait speed (p < 0.05) in the ERT group compared to the control group. ERT also increased muscle strength (p < 0.05) and mobility in lower limbs as observed in FTSS and TUG tests (p < 0.05) at post-intervention compared to the baseline. In the ERT group, significant positive changes were observed in Beta1 band power, Theta band power, and Alpha1 band whole brain connectivity (p < 0.005) compared to the control group. Conclusions: Our findings showed that ERT can improve muscle and brain function in middle-aged and older adults during a four-week intervention program whereas significant improvements were not observed with RT. Therefore might be one of the feasible alternative intervention to RT for the prevention of muscle loss whilst improving brain function for middle-aged and older population.

Associations of grip strength, walking pace, and the risk of incident dementia: A prospective cohort study of 340212 participants

INTRODUCTION

Grip strength and walking pace have been linked to cognitive dysfunction. Their relationships, however, demand further clarification as the evidence is derived primarily from less-comprehensive investigations.

METHODS

A total of 340212 UK Biobank participants without dementia and cardiovascular diseases at baseline were analyzed. Cox proportional hazard models assessed the longitudinal associations.

RESULTS

Over a mean follow-up of 8.51 ± 2.68 years, 2424 incident dementia cases were documented. A 5 kg increment of absolute grip strength was associated with lower risks of all-cause dementia (hazard ratio [HR] 0.857), Alzheimer's disease (HR 0.874), and vascular dementia (HR 0.788). The patterns of associations remained similar when grip strength was expressed in relative terms and quintiles. A slow walking pace demonstrated consistent associations with increased risks of all dementia types.

DISCUSSION

Our findings provide amplified evidence and suggest that muscle fitness, reflected by objective grip strength measures and self-reported walking pace, may be imperative for estimating the risks of dementia.

[Physical activity in the elderly with other major neurocognitive disorders]

For decades, the literature was skeptical about the feasibility of motor rehabilitation and its impact, as well as that of physical activity (PA), in subjects with major neurocognitive disorders (MNCD), including Alzheimer's disease. Now, authors report several benefits of PA, both physical and cognitive, by promoting brain perfusion, neurogenesis and synaptic plasticity, as well as decreasing oxidative stress and inflammation. PA should be recommended in cases of TNCM.

Grip Strength Trajectories and Cognition in English and Chilean Older Adults: A Cross-Cohort Study

Growing evidence about the link between cognitive and physical decline suggests the early changes in physical functioning as a potential biomarker for cognitive impairment. Thus, we compared grip-strength trajectories over 12-16 years in three groups classified according to their cognitive status (two stable patterns, normal and impaired cognitive performance, and a declining pattern) in two representative UK and Chilean older adult samples. The samples consisted of 7069 UK (ELSA) and 1363 Chilean participants (ALEXANDROS). Linear Mixed models were performed. Adjustments included socio-demographics and health variables. The Declined and Impaired group had significantly lower grip-strength at baseline when compared to the Non-Impaired. In ELSA, the Declined and Impaired showed a faster decline in their grip strength compared to the Non-Impaired group but differences disappeared in the fully adjusted models. In ALEXANDROS, the differences were only found between the Declined and Non-Impaired and they were partially attenuated by covariates. Our study provides robust evidence of the association between grip strength and cognitive performance and how socio-economic factors might be key to understanding this association and their variability across countries. This has implications for future epidemiological research, as hand-grip strength measurements have the potential to be used as an indicator of cognitive performance.

Estimating balance, cognitive function, and falls risk using wearable sensors and the sit-to-stand test

The five times sit-to-stand test (FTSS) is an established functional test, used clinically as a measure of lower-limb strength, endurance and falls risk. We report a novel method to estimate and classify cognitive function, balance impairment and falls risk using the FTSS and body-worn inertial sensors. 168 community dwelling older adults received a Comprehensive Geriatric Assessment which included the Mini-Mental State Examination (MMSE) and the Berg Balance Scale (BBS). Each participant performed an FTSS, with inertial sensors on the thigh and torso, either at home or in the clinical environment. Adaptive peak detection was used to identify phases of each FTSS from torso or thigh-mounted inertial sensors. Features were then extracted from each sensor to quantify the timing, postural sway and variability of each FTSS. The relationship between each feature and MMSE and BBS was examined using Spearman's correlation. Intraclass correlation coefficients were used to examine the intra-session reliability of each feature. A Poisson regression model with an elastic net model selection procedure was used to estimate MMSE and BBS scores, while logistic regression and sequential forward feature selection was used to classify participants according to falls risk, cognitive decline and balance impairment. BBS and MMSE were estimated using cross-validation with low root mean squared errors of 2.91 and 1.50, respectively, while the cross-validated classification accuracies for balance impairment, cognitive decline, and falls risk were 81.96, 72.71, and 68.74%, respectively. The novel methods reported provide surrogate measures which may have utility in remote assessment of physical and cognitive function.

Handgrip strength and all-cause dementia incidence and mortality: findings from the UK Biobank prospective cohort study

BACKGROUND

This study aimed to investigate the associations of grip strength with incidence and mortality from dementia and whether these associations differ by sociodemographic and lifestyle factors.

METHODS

A total of 466 788 participants of the UK Biobank (median age 56.5 years, 54.5% women). The outcome was all-cause dementia incidence and mortality and the exposure was grip strength. Grip strength was assessed using a Jamar J00105 hydraulic hand dynamometer.

RESULTS

Excluding the first 2 years of follow-up (landmark analysis), mean follow-up was 9.1 years (inter-quartile range: 8.3; 9.7) for incidence and 9.3 (inter-quartile range: 8.7; 10.0) for mortality. During this time, 4087 participants developed dementia, and 1309 died from it. Lower grip strength was associated with a higher risk of dementia incidence and mortality independent of major confounding factors (P < 0.001). Individuals in the lowest quintile of grip strength had 72% [95% confidence interval (CI): 1.55; 1.92] higher incident dementia risk and 87% [95% CI: 1.55; 2.26] higher risk of dementia mortality compared with those in the highest quintile. Our PAF analyses indicate that 30.1% of dementia cases and 32.3% of dementia deaths are attributable to having low grip strength. The association between grip strength and dementia outcomes did not differ by lifestyle or sociodemographic factors.

CONCLUSIONS

Lower grip strength was associated with a higher risk of all-cause dementia incidence and mortality, independently of important confounding factors.

Asymmetrical Handgrip Strength Is Associated with Lower Cognitive Performance in the Elderly

(1) Background: Several studies have reported that handgrip strength (HGS) may be a sign of lower cognitive performance. However, studies supporting an association between asymmetrical HGS and cognitive function are lacking. This study aimed to determine the association between asymmetrical HGS and cognitive performance among the elderly. (2) Methods: The study sample included 2729 individuals aged ≥60 years-old who participated in the 2011-2014 National Health and Nutrition Examination Survey. The cognitive tests consisted of the word learning and recall modules from the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), Animal Fluency Test, and Digit Symbol Substitution Test (DSST). HGS was measured using a handgrip dynamometer, and asymmetrical HGS was used to calculate HGS. (3) Results: Of the 2729 participants, 53.0% were aged 60 to 69 years-old, and 47.0% were aged 70 years and older. All cognitive performance scores were significantly correlated with asymmetrical HGS in both age groups. After adjusting for confounders, there was a significant association between DSST and HGS asymmetry in both age groups. Contrastingly, a significant association was only observed for the relationship between the CERAD test and HGS asymmetry in the ≥70 year-old group. (4) Conclusions: We found that low cognitive function was associated with asymmetrical HGS in elderly participants in the United States. Thus, asymmetrical HGS may be an important predictor of cognitive deficits. However, further research is required to confirm our results and to establish possible mechanisms.

The Effectiveness of GRADIOR: A Neuropsychological Rehabilitation Program for People with Mild Cognitive Impairment and Mild Dementia. Results of a Randomized Controlled Trial After 4 and 12 Months of Treatment

BACKGROUND

Computer-based cognitive training programs have been developed with promising results on the maintenance/improvement of cognitive performance in people with dementia.

OBJECTIVE

The objective was to evaluate the effectiveness of the cognitive rehabilitation program "GRADIOR" in people with mild cognitive impairment and mild dementia.

METHOD

This study was a single-blind multicenter randomized clinical trial. Participants were recruited from hospitals/day centers. The experimental group (EG) and control group (CG) received computer-based cognitive training (CCT) and routine daily care, respectively. Outcome measures at T0: baseline, T1: at 4 months, T2: at 12 months were compared within and between-groups.

RESULTS

Significant differences or important effect sizes were detected at the intragroup and intergroup level for most variables, observing a trend of improvement and/or maintenance at 4 months by Visual Reasoning of Cambridge Cognitive Examination (CAMCOG), Digit and Arithmetic of WAIS-III, Semantic Verbal Fluency, Mini-Mental State Exam (MMSE), Trail Making Test (TMT)-A-Mistakes and at 12 months by Visual Reasoning of CAMCOG, Digit Symbol of WAIS-III, TMT-B-mistakes, Visual Memory of Rivermead Behavioural Memory Test, Lexical Verbal Fluency-P, Yesavage's Geriatric Depression Scale (GDS), TMT-A-time scales whose objective was to evaluate some executive functions and/or the memory. The CG presented a worsening trend for most of the measures towards 12 months. There was also a significant interaction between "time and group" for MMSE (F = 8.971; p = 0.03; η 2 = 0.019) and the GDS (F = 3.414; p = 0.04; η 2 = 0.041), as well as small effect sizes for TMT-A-time (F = 1.641; p = 0.21; η 2 = 0.021) and TMT-A-mistakes (F = 0.908; p = 0.41; η 2 = 0.019).

CONCLUSION

CCT with GRADIOR has been proved to benefit cognitive functions (ISRCTN:15742788).

STEP-UP: Enabling Low-Cost IMU Sensors to Predict the Type of Dementia During Everyday Stair Climbing

Posterior Cortical Atrophy is a rare but significant form of dementia which affects people's visual ability before their memory. This is often misdiagnosed as an eyesight rather than brain sight problem. This paper aims to address the frequent, initial misdiagnosis of this disease as a vision problem through the use of an intelligent, cost-effective, wearable system, alongside diagnosis of the more typical Alzheimer's Disease. We propose low-level features constructed from the IMU data gathered from 35 participants, while they performed a stair climbing and descending task in a real-world simulated environment. We demonstrate that with these features the machine learning models predict dementia with 87.02% accuracy. Furthermore, we investigate how system parameters, such as number of sensors, affect the prediction accuracy. This lays the groundwork for a simple clinical test to enable detection of dementia which can be carried out in the wild.

Association of Cognitive Performance with Frailty in Older Individuals with Cognitive Complaints

OBJECTIVES

Frailty is a risk factor for poor cognitive performance in older adults. However, few studies have evaluated the association of cognitive performance with frailty in a low- to middle-income country (LMIC). This study aimed to investigate an association between cognitive performance and frailty in older adults with memory complaints in Brazil. Secondarily, we aim to assess an association of cognitive performance with gait speed and grip strength.

DESIGN

Cross-sectional study.

SETTING

Outpatient service from a LMIC.

PARTICIPANTS

Older adults with memory complaints reported by the participants, their proxies, or their physicians.

MEASUREMENTS

Frailty was evaluated using the Cardiovascular Health Study criteria. A neuropsychological battery evaluated memory, attention, language, visuospatial function, executive function. Linear regression analysis with adjustment for age, sex, and education was used. We also evaluated the interaction of education with frailty, grip strength, and gait speed.

RESULTS

Prefrailty was associated with poor performance in the memory domain, as well as slower gait speed was associated with worse performance in memory, attention, language, and executive function. Frailty and grip strength were not associated with cognitive performance. Interactions of education with gait speed were significant for global performance, as well as for attention and visuospatial ability.

CONCLUSION

In elderly patients with memory complaints, prefrailty was associated with poor memory performance. Slowness was associated with poorer performance in some cognitive domains, mainly in participants with low education.

Fine or Gross Motor Index as a Simple Tool for Predicting Cognitive Impairment in Elderly People: Findings from The Irish Longitudinal Study on Ageing (TILDA)

BACKGROUND

Several kinds of motor dysfunction can predict future cognitive impairment in elderly individuals. However, the ability of the fine motor index (FINEA) and gross motor index (GROSSA) to predict the risk of cognitive impairment has not been assessed.

OBJECTIVE

We investigated the associations between FINEA/GROSSA and cognitive impairment.

METHODS

The data of 4,745 participants from The Irish Longitudinal Study on Ageing (TILDA) were analyzed. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). We first assessed the correlation between the FINEA/GROSSA and MMSE in a cross-sectional study. Then, we further investigated the predictive role of the incidence of cognitive impairment in a prospective cohort study.

RESULTS

We found that both FINEA and GROSSA were negatively correlated with MMSE in both the unadjusted (FINEA: B = -1.00, 95%confidence intervals (CI): -1.17, -0.83, t = -11.53, p < 0.001; GROSSA: B = -0.85, 95%CI: -0.94, -0.76, t = -18.29, p < 0.001) and adjusted (FINEA: B = -0.63, 95%CI: -0.79, -0.47, t = -7.77, p < 0.001; GROSSA: B = -0.57, 95%CI: -0.66, -0.48, t = -12.61, p < 0.001) analyses in a cross-sectional study. In a prospective cohort study, both high FINEA and high GROSSA were associated with an increased incidence of cognitive function impairment (FINEA: adjusted odds ratios (OR) = 2.35, 95%CI: 1.05, 5.23, p = 0.036; GROSSA adjusted OR = 3.00, 95%CI: 1.49, 6.03, p = 0.002) after 2 years of follow-up.

CONCLUSION

Higher FINEA and GROSSA scores were both associated with an increased incidence of cognitive impairment. FINEA or GROSSA might be a simple tool for identifying patients with cognitive impairment.

Identification of Disability Risk in Addition to Slow Walking Speed in Older Adults

INTRODUCTION

A cutoff speed of 1.0 m/s for walking at a comfortable pace is critical for predicting future functional decline. However, some older adults with walking speeds below the cutoff point maintain an independent living. We aimed to identify specific predictors of disability development in older adults with slow walking speeds in contrast to those with a normal walking speed.

METHODS

This prospective cohort study on 12,046 community-dwelling independent Japanese older adults (mean age, 73.6 ± 5.4 years) was conducted between 2011 and 2015. Participants were classified into slow walking speed (comfortable walking speed slower than 1.0 m/s) and normal walking speed (speed of 1.0 m/s or faster) groups and followed up to assess disability incidence for 24 months after baseline assessments. Cox proportional hazards regression models were used to identify predictors of disability development in the slow and normal walking groups.

RESULTS

Overall, 26.8% of participants had a slow walking speed. At follow-up, 17.3% and 5.1% of participants in the slow and normal walking groups, respectively, developed disability (p < 0.01). Cox regression models revealed that age (hazard ratio 1.07, 95% confidence interval 1.05-1.09), walking speed (0.12, 0.07-0.22), grip strength (0.97, 0.95-0.99), Parkinson's disease (4.65, 2.59-8.33), word list memory-immediate recognition score (0.90, 0.85-0.97), word list memory-delayed recall score (0.94, 0.89-1.00), Symbol Digit Substitution Test (SDST) score (0.98, 0.96-0.99), and 15-item Geriatric Depression Scale (GDS) score (1.04, 1.01-1.07) were significantly associated with disability incidence in the slow walking group. In the normal walking group, age, grip strength, depression, diabetes, cognition, GDS score, and reduced participation in outdoor activity were significantly associated with disability incidence; however, there was no significant association with walking speed.

CONCLUSIONS

Decreased walking speeds have considerably greater impact on disability development in older adults with a slow walking speed than in those with a normal walking speed. Health-care providers should explore modifiable factors for reducing walking speed; they should also encourage improvement of risk factors such as muscle weakness and depression to reduce disability risk in older adults with slow walking speeds.

A combined stepping and visual tracking task predicts cognitive decline in older adults better than gait or visual tracking tasks alone: a prospective study

BACKGROUND

It is unclear whether motor-cognitive dual tasks predict cognitive decline better than either motor or cognitive tasks alone.

AIMS

To examine the utility of the novel motor-cognitive dual-task test [Stepping Trail Making Test (S-TMT)], as a predictor of cognitive decline, and compare its predictive performance with single motor or cognitive tests.

METHODS

This 2-year population-based prospective study included 626 adults aged ≥ 70 years from Takashimadaira, Itabashi, Tokyo. The S-TMT measured the time taken to step on 16 numbers in order. Gait speed and TMT-A were assessed with standardized methods as single motor and cognitive tasks, respectively. A decline in the Mini-Mental State Examination score by ≥ 3 points over 2 years was defined as a significant cognitive decline.

RESULTS

Over 2 years, 97 (15.5%) experienced cognitive decline. After adjusting for confounders, binary logistic regression models showed no significant associations between gait speed, TMT-A time tertiles, and risk of cognitive decline, but participants in the longest tertile of S-TMT time were more likely to develop cognitive decline than those of the shortest tertile (odds ratio 2.14; 95% confidence interval 1.17-3.90). Only the addition of the S-TMT time to the covariates model significantly improved the reclassification indices for predicting cognitive decline (net reclassification improvement: 0.31, P < 0.01; integrated discrimination improvement: 0.01, P = 0.02).

DISCUSSION AND CONCLUSION

Only the S-TMT was significantly associated with cognitive decline and improved reclassification indices, indicating that it is more useful for predicting cognitive decline than individual gait speed or visual tracking tests alone.

Development of a Conceptual Framework for Severe Self-Neglect (SN) by Modifying the CREST Model for Self-Neglect

Self-neglect is an inability or refusal to meet one's own basic needs as accepted by societal norms and is the most common report received by state agencies charged with investigating abuse, neglect and exploitation of vulnerable adults. Self-neglect is often seen in addition to one or multiple conditions of frailty, mild to severe dementia, poor sleep and depression. While awareness of elder self-neglect as a public health condition and intervention has significantly risen in the past decade as evidenced by the increasing amount of literature available, research on self-neglect still lacks comprehensiveness and clarity since its inception to the medical literature in the late 1960s. With the burgeoning of the older adult population, commonness of self-neglect will most likely increase as the current incidence rate represents only the "tip of the iceberg" theory given that most cases are unreported. The COVID-19 pandemic has exacerbated the incidence of self-neglect in aged populations and the need for the use of intervention tools for aging adults and geriatric patients living alone, many of which may include in-home artificial intelligence systems. Despite this, little research has been conducted on aspects of self-neglect other than definition and identification. Substantial further study of this disorder's etiology, educating society on early detection, and conceivably preventing this syndrome altogether or at least halting progression and abating its severity is needed. The purpose of this research is to provide a definition of severe self-neglect, identify key concepts related to self-neglect, comprehensively describe this syndrome, present a conceptual framework and analyze the model for its usefulness, generalizability, parsimony, and testability.

Age- and Gender-Related Changes in Physical Function in Community-Dwelling Brazilian Adults Aged 50 to 102 Years

BACKGROUND AND PURPOSE

Cutoff points for physical function tests are commonly used in clinical practice for the evaluation, monitoring, and treatment of older adults. Previous studies have shown that, while age-related patterns of muscle strength change are similar between ethnic groups, strength values differ significantly independent of age. Whether the same applies to other physical function tests is presently unclear. This study investigated age- and gender-related changes of performance on a battery of physical function tests in Brazilian community dwellers.

METHODS

The study followed a cross-sectional design. Participants were community-dwelling adults. Candidates were considered eligible if they were 18 years or older, lived independently, and possessed sufficient physical and cognitive abilities to perform all of the measurements required by the protocol. Physical function tests included isometric handgrip (IHG), 5 times sit-to-stand (5×STS) test, Timed Up and Go, 1-leg stance, and walking speed (WS) at usual and fast pace.

RESULTS

Two-thousand eight-hundred and four people were enrolled. Mean age was 68.0 (7.0) years (range 50-102 years), and 2262 (80.7%) were women. Men displayed better IHG and balance, while women showed higher performance on the 5×STS and WS tests. A gender-specific pattern of decline in physical performance was observed. Specifically, women showed a linear age-dependent decline in all tests. In men, only in the IHG, 1-leg stance, and WS test at a fast pace was there a linear decline with age. In both genders, the lowest mean values of physical function tests were higher than the proposed cutoffs for sarcopenia.

DISCUSSION AND CONCLUSIONS

Our findings indicate that the performance on different physical function tests decreases with advancing age in Brazilian adults, following a gender-specific pattern. In none of the tests did the lowest mean values reach the cutoffs for sarcopenia. This suggests that region-specific cutoffs might be necessary to identify older people at risk of adverse events.

Associations between physical function and device-based measures of physical activity and sedentary behavior patterns in older adults: moving beyond moderate-to-vigorous intensity physical activity

Background

Research supports that moderate-to-vigorous intensity physical activity (MVPA) is key to prolonged health and function. Among older adults, substantial changes to MVPA may be infeasible, thus a growing literature suggests a shift in focus to whole-day activity patterns.

Methods

With data from 795 older adults aged 65–100 in the Adult Changes in Thought Activity Monitoring study, we used linear regression to estimate associations between ActiGraph and activPAL measured activity patterns – including light intensity physical activity, steps, standing, and sedentary behaviors – and physical function as measured by a short Performance-based Physical Function (sPPF) score (range 0–12), a composite score based on three standardized physical performance tasks: gait speed, timed chair stands, and grip strength. We examined whether relationships persisted when controlling for MVPA or differed across age, gender, or quartiles of MVPA.

Results

In models unadjusted for MVPA, a 1-standard deviation (SD) increment of daily sitting (1.9 h more), mean sitting bout duration (8 min longer average), or time spent in sedentary activity (1.6 h more) was associated with ~ 0.3–0.4 points lower mean sPPF score (all p < 0.05). A 1-SD increment in daily steps (~ 3500 more steps) was associated with ~ 0.5 points higher mean sPPF score (95% CI: 0.22 to 0.73). MVPA adjustment attenuated all relationships. The association between physical function and steps was strongest among adults aged 75+; associations of worse function with greater sedentary behavior were more pronounced in participants with the lowest levels of MVPA.

Conclusions

We found associations between function and activity metrics other than MVPA in key subgroups, findings that support research on broader activity patterns and may offer ideas regarding practical intervention opportunities for improving function in older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02163-4.

Challenging the relationship of grip strength with cognitive status in older adults

OBJECTIVE

Grip strength is a widely used motor assessment in ageing research and has repeatedly been shown to be associated with cognition. It has been proposed that grip strength could enhance cognitive screening in experimental or clinical research, but this study uses multiple data-driven approaches to caution against this interpretation. Furthermore, we introduce an alternative motor assessment, comparable to grip dynamometry, but has a more robust relationship with cognition among older adults.

DESIGN

Associations between grip strength and cognition (measured with the Montreal Cognitive Assessment) were analysed cross sectionally using multivariate regression in two datasets: (1) The Irish LongituDinal Study on Ageing (TILDA; N = 5,980, community-dwelling adults ages 49-80) and (2) an experimental dataset (N = 250, community-dwelling adults aged 39-98). Additional statistical simulations on TILDA tested how ceiling effects or skewness in these variables influenced these associations for quality control.

RESULTS

Grip strength was significantly but weakly associated with cognition, consistent with previous studies. Simulations revealed this was not due to skewness/ceiling effects. Conversely, a new alternative motor assessment (functional reaching [FR]) had a stronger, more robust and more sensitive relationship with cognition compared to grip strength.

CONCLUSIONS

Grip strength should be cautiously interpreted as being associated with cognition. However, FR may have a stronger and clinically useful relationship with cognition.

CCCDTD5 recommendations on early non cognitive markers of dementia: A Canadian consensus

Introduction

Cognitive impairment is the hallmark of Alzheimer's disease (AD) and related dementias. However, motor decline has been recently described as a prodromal state that can help to detect at‐risk individuals. Similarly, sensory changes, sleep and behavior disturbances, and frailty have been associated with higher risk of developing dementia. These clinical findings, together with the recognition that AD pathology precedes the diagnosis by many years, raises the possibility that non‐cognitive changes may be early and non‐invasive markers for AD or, even more provocatively, that treating non‐cognitive aspects may help to prevent or treat AD and related dementias.

Methods

A subcommittee of the Canadian Consensus Conference on Diagnosis and Treatment of Dementia reviewed areas of emerging evidence for non‐cognitive markers of dementia. We examined the literature for five non‐cognitive domains associated with future dementia: motor, sensory (hearing, vision, olfaction), neuro‐behavioral, frailty, and sleep. The Grading of Recommendations Assessment, Development, and Evaluation system was used to assign the strength of the evidence and quality of the recommendations. We provide recommendations to primary care clinics and to specialized memory clinics, answering the following main questions: (1) What are the non‐cognitive and functional changes associated with risk of developing dementia? and (2) What is the evidence that sensory, motor, behavioral, sleep, and frailty markers can serve as potential predictors of dementia?

Results

Evidence supported that gait speed, dual‐task gait speed, grip strength, frailty, neuropsychiatric symptoms, sleep measures, and hearing loss are predictors of dementia. There was insufficient evidence for recommending assessing olfactory and vision impairments as a predictor of dementia.

Conclusions

Non‐cognitive markers can assist in identifying people at risk for cognitive decline or dementia. These non‐cognitive markers may represent prodromal symptoms and several of them are potentially amenable to treatment that might delay the onset of cognitive decline.

The Alzheimer patient from the dermatologist's point of view

Alzheimer's disease (AD) is characterized by a cluster of signs and symptoms that include memory loss, language disturbances, psychological and psychiatric changes and difficulty in carrying out daily activities. Although it may seem to be far from a dermatologic competence, the ageing of populations in industrialized and developing countries has changed things, making AD a multidisciplinary question. Indeed, this neurodegenerative disorder is not exclusively neurological, but rather may involve multiple tissues and organs. The abnormalities in metabolic and biochemical processes described in affected brains are also present in the skin and may condition specific dermatological manifestations. In fact, although a history of non-melanoma skin cancer is linked to a significantly reduced risk of developing AD, this is not so for melanoma. Several biological, social and environmental hypotheses can be advanced to explain these correlations. AD patients' memory problems and the partial inability to express an informed consent, could make a simple tumor excision challenging for a dermatologic surgeon. Moreover, attention should also be paid to the possibility of pharmacological interactions with AD therapies and to surgery timing. Observational studies have provided evidence for a non-spurious correlation between bullous pemphigoid (BP) and dementia. The demonstration of neurological isoforms of both BP180 and BP230 in the central nervous system has provided partial explanations for these findings and raised the question as to whether AD patients should be given accurate screening for BP and vice versa. Some adverse skin reactions have been observed with AD drugs and although mainly localized others are diffuse. Importantly, some of these drugs are available for administration in a patch or systemic form. When dealing with bedridden patients, the skin examination should be as complete as possible, since ulcer location is not only influenced by pressure and paratonia but also by spasticity, conditioning wounds in atypical sites.

Sarcopenia and frailty in individuals with dementia: A systematic review

BACKGROUND

Population aging has resulted in an increase in age-related conditions. Sarcopenia, the progressive loss of muscle mass and strength, and frailty, vulnerability to poor resolution of homeostasis after a stressor, are common causes of functional decline in older individuals. There is a paucity of work on how they interrelate with dementia. The objective of this review was to examine the literature on sarcopenia and frailty in dementia.

METHODS AND RESULTS

Studies of sarcopenia and frailty in dementia were searched for in EMBASE, PubMed and Web of Science, and via hand-searching. Citations were screened for independently by two reviewers, with disagreements resolved by a third reviewer. To be eligible for inclusion, the articles needed to fulfil: (1) English language; (2) human studies; and (3) full-text available. Dementia of any aetiology was included. 303 non-duplicate recorders were identified, of which 270 irrelevant papers were excluded. Of the remaining 33, 27 examined frailty and 13 sarcopenia, with six of these measuring both. An increased prevalence of frailty and sarcopenia was noted in dementia patients. However, nine papers did not specify dementia aetiologies. Of those that did (n = 21), 20 examined Alzheimer's disease, with three also including Lewy body dementia, three vascular dementia, and one Parkinson's disease dementia.

CONCLUSION

Most papers examined frailty, rather than sarcopenia, in dementia. The studies were heterogeneous, using different protocols and non-validated definitions. However, dementia patients may have an increased prevalence of frailty and sarcopenia. This review highlights key gaps in accurate diagnosis of frailty/sarcopenia and in non-Alzheimer's dementia.

Associating Gait Phase and Physical Fitness with Global Cognitive Function in the Aged

This study aimed to identify classifier variables by considering both gait and physical fitness for identifying adults aged over 75 years and global cognitive function declines in older adults. The participants included 735 adults aged 65–89 years who were asked to walk at three different speeds (slower, preferred, and faster) while wearing inertial measurement units embedded in shoe-type data loggers and to perform nine physical fitness tests. The variability in the stance phase as well as the strength, balance, and functional endurance showed a strong dependence on the age being over 75 years. The cognitive function was evaluated by the Mini-Mental State Examination; a longer stance phase at a slower walking speed and decreased grip strength and five times sit-to-stand were associated with cognitive function. These findings may be useful for determining the decline in physical performance of older adults. A longer stance phase and decreased grip strength and five times sit-to-stand may be factors that help distinguish declines in cognitive function from normal age-related declines.

Dementia, Comorbidity, and Physical Function in the Program of All-Inclusive Care for the Elderly

BACKGROUND

Participants in the Program of All-Inclusive Care for the Elderly (PACE) are a unique clinical population of medically complex and highly disabled older adults who qualify for nursing home level care but receive services in the community. A main goal of PACE programs is to prevent further declines in physical function that may necessitate costly institutionalization. This study evaluates how multimorbidity and dementia impact both self-selected gait speed and Timed Up and Go (TUG) in this population.

METHODS

This study was a cross-sectional design. Sociodemographic information, physical function, comorbidity data, and dementia status on 525 PACE participants were extracted from a quality improvement database. Separate univariable and multivariable linear regression models were used to evaluate the impact of comorbidity status and dementia on gait speed and TUG time.

RESULTS

PACE participants overall have a high degree of functional disability, with an average gait speed of 0.66 m/s, an average Short Physical Performance Battery score of 6.0/12, and an average TUG time of nearly 20 s. In the univariable analysis, a higher number of comorbidities and a diagnosis of dementia were associated with greater limitation for gait speed and TUG time. After adjusting for age, sex, strength, and balance, each additional comorbidity was independently associated with 0.015 m/s slower gait speed, as well as a 3.5% increase in TUG time for PACE participants with dementia.

CONCLUSIONS

Ambulatory PACE participants have average levels of physical function that are dangerously close to thresholds thought to indicate vulnerability for further disability development, hospitalization, and nursing home admission. Both dementia and comorbidity burden are associated with declines in physical function, and the interaction between these risk factors is a telling indicator to functional decline in higher-level ambulatory tasks. PACE program clinicians can use this information to better identify participants at risk for limited physical function. Further research should investigate consequences of functional decline and determine optimal intervention strategies for PACE participants with functional impairments.

Motoric cognitive risk syndrome: Integration of two early harbingers of dementia in older adults

Dementia is characterized by a long preclinical phase that may last years to decades before the onset of mild cognitive impairment. Slow gait speed and subjective memory complaint commonly co-occur during this preclinical phase, and each is a strong independent predictor of cognitive decline and dementia. Motoric cognitive risk (MCR) syndrome is a pre-dementia syndrome that combines these two early harbingers of dementia. The risk of cognitive decline or dementia is stronger for MCR than for either slow gait speed or subjective memory complaint alone. Slow gait speed and subjective memory complaint have several common risk factors: cardiovascular disease, diabetes mellitus, abnormal cortisol profiles, low vitamin D levels, brain atrophy with decreased hippocampal volume, and increased deposition of beta-amyloid in the brain. The underlying pathogenesis of MCR remains poorly understood. Metabolomics and proteomics have great potential to provide new insights into biological pathways involved in MCR during the long preclinical phase preceding dementia.