Physical performance across the cognitive spectrum and between dementia subtypes in a population-based sample of older adults: The HUNT study

Gait speed as a superior screening indicator for mild cognitive impairment compared to walk ratio and dual-task cost: a cross-sectional study

BACKGROUND

The accurate and sensitive quantitative indicator for screening patients with subjective cognitive decline (SCD) and mild cognitive impairment (MCI) has not yet been established.

METHODS

Our study involved the measurement and comparison of clinical features and gait indicators among 96 patients with MCI, 66 patients with SCD, and 50 individuals with normal cognition (NC). Receiver operating characteristic (ROC) curve, multiple logistic regression, correlation clustering heatmap plot, and random forest modeling were used to evaluate the ability of gait indicators to differentiate disease.

RESULTS

No significant differences were observed in gait parameters between control and SCD groups [dual-task cost (DTC): p = 0.579; single-task gait speed: p = 0.656; dual gait speed: p = 0.951; single-task walk ratio: p = 0.683; dual-task walk ratio: p = 0.657]. Principal component analysis (PCA) revealed no distinct clustering patterns between these groups. For MCI discrimination, gait speed showed moderate predictive value (control vs. MCI: single-task AUC = 0.725, dual-task AUC = 0.726; SCD vs. MCI: single-task AUC = 0.733, dual-task AUC = 0.750). Both single-task (r = 0.36) and dual-task (r = 0.37) speeds correlated positively with MMSE scores. Multiple logistic regression identified single speed as a significant predictor of MCI (single-task: OR = 1.047; dual-task: OR = 1.05). Random forest analysis confirmed the importance of dual-task speed (mean decrease accuracy = 24.99).

CONCLUSION

This study identifies gait speed as superior to walk ratio and DTC for MCI detection, supporting its clinical adoption as a frontline screening tool.

A Narrative Review of Physical Performance Changes in Dementia: Differences between Community and Nursing Home Setting

OBJECTIVES

To investigate differences in longitudinal physical performance in individuals with dementia across care settings.

DESIGN

Narrative review.

SETTING AND PARTICIPANTS

Older adults with moderate to severe dementia residing in the community or nursing home.

METHODS

A systematic literature search was conducted in PubMed, Embase, and Web of Science. Included studies were longitudinal, with observational or care-as-usual control groups, with a follow-up ≥3 months, assessing physical performance in adults aged ≥65 years with dementia (Mini Mental State Examination score ≤20), in the community or nursing home setting. Eligibility screening and risk of bias were performed by 2 authors. We categorized physical performance-based tests into upper limb strength, lower limb strength, balance, endurance, flexibility, mobility, and combined physical performance. Physical performance changes were quantified within each study as percentage of change from baseline to follow-up, and were compared between community and nursing home setting using narrative synthesis.

RESULTS

The search yielded 7813 studies, of which 20 were included (15 from nursing homes). Five of 20 studies were classified as having high risk of bias. In the nursing home setting, physical performance decline was observed across all domains (3- to 4-month follow-up: -6.1% to -7.7%, 5- to 7.5-month follow-up: -4.6% to -30.7%, 12- to 36-month follow-up: -27.3% to -68.2%). In the community setting, only combined physical performance declined (12-24 months: -18.6% to -33.8%).

CONCLUSIONS AND IMPLICATIONS

Studies assessing longitudinal physical performance in the community and nursing home setting were identified and summarized. Physical performance declined after shorter follow-up periods across all domains in the nursing home setting, whereas in the community setting only combined physical performance declined. However, diversity in study characteristics, study populations and outcome measures, along with a deficiency of longer follow-up periods in the community setting, hamper interpretation. Future research should focus on physical performance trajectories in longitudinal within-group designs of community-dwelling individuals with dementia who transition to nursing homes.

Effectiveness of an intervention combining motor-cognitive training and arch support insoles in improving the physical performance of older adults with mild cognitive impairment: A randomized controlled trial

OBJECTIVES

To investigate the efficacy of an intervention combining motor-cognitive training with arch support insoles for older adults with mild cognitive impairment (MCI).

METHODS

Twenty-nine participants were randomly assigned to an experimental or a control group. The experimental group underwent a 12-week intervention programme comprising three 1-hour motor-cognitive training sessions weekly and wore arch support insoles every day. The control group received motor-cognitive training alone. The functional reach, timed-up-and-go (TUG), 10-m hurdle walking test, Short Physical Performance Battery (SPPB), and Montreal Cognitive Assessment (MoCA) were administered before and after the interventions.

RESULTS

The experimental group exhibited significant improvement across all assessments (p < .05), whereas the control group demonstrated significant improvement only in the TUG test, the 5× chair stand subtest of the SPPB, and MoCA scores (p < .05).

CONCLUSIONS

The proposed intervention is recommended for improving cognitive and physical performance in older adults with MCI.

Validation of an algorithm for detecting turning in people with cognitive impairment, considering dementia disease subtype

BACKGROUND

Turning manoeuvres are an essential component of mobility and are vital for effective real-world navigation. Turning is more challenging than straight-line walking, involving complex cognitive functions to execute multi-segment co-ordination. Therefore, people with cognitive impairment (PwCI) may be more susceptible to impaired turning performance. Inertial measurement units (IMUs) can be used to quantify turning performance; however, IMU-based algorithms have not yet been validated for PwCI, or across dementia disease subtypes.

RESEARCH QUESTION

Is a custom-built algorithm for accurately detecting turn start and end valid for use in PwCI and in different dementia disease subtypes?

METHODS

Sixty-six PwCI due to Alzheimer's disease, Lewy body disease and vascular dementia, along with 23 cognitively healthy older adults (controls) were included. Participants wore an IMU on their lower back while completing six 10-m intermittent walks, segmented by 180° turns. A 2D colour video camera was used as the reference system. Videos were reviewed by two independent blinded raters annotating turn start and end. Agreement (intra-class correlation (ICC (2,1)), Spearman's rho and Limits of agreement) and error (Root mean square error; RMSE and bias) between the raters (rater 1 vs. 2) and the algorithm (rater vs. algorithm) were evaluated.

RESULTS

There was excellent agreement (rater-rater and rater-algorithm) for detecting turn start and end for PwCI and across dementia disease subtypes (rho = 1.00, ICC = 1.00). The error between raters was lower (RMSE < 0.72 s, bias < 0.41 s) than the error between raters and algorithm (RMSE < 1.29 s, bias < 1.4 s). Error was lowest for controls (RMSE < 0.94 s), followed by AD (RMSE < 1.21 s) and LBD (RMSE < 1.29 s).

SIGNIFICANCE

Key findings suggest that this algorithm can detect turn start and end using an IMU in PwCI in agreement with a reference system (video ratings). Future research should consider the clinical application of turning assessment in PwCI, such as its ability to differentiate dementia disease subtypes to support accurate diagnosis.

A new paradigm for neurodegenerative diseases classification: A clinical perspective

A vast progress has been made in the understanding of neurodegenerative diseases during the past few years. However, clinical diagnostic accuracy continues to be very low, despite the introduction of various diagnostic tools and repeated revisions of diagnostic criteria. For instance, patients with Alzheimer's disease (AD) may present with symptoms that overlap with other neurodegenerative conditions like dementia with Lewy bodies (DLB), making accurate diagnosis challenging. This diagnostic uncertainty can lead to delayed or incorrect treatment, significantly impacting patients' quality of life and prognosis. Thus, the definite diagnosis still relies on post-mortem pathological findings, placing a significant burden on both clinicians and researchers. As a growing body of evidence indicates, co-pathology seems to be the rule among neurodegenerative diseases. Additionally, a single pathological diagnosis, such as AD, can manifest in various clinical presentations, ranging from predominantly cognitive impairment to significant motor symptoms. Each of these presentations currently requires its own set of complicated diagnostic criteria. Perhaps, the time has come for a much-needed radical revision of existing clinical diagnostic criteria. Inclusion of patients do not neatly fit into existing diagnostic categories for neurodegenerative diseases, in future large-scale, longitudinal studies and/or clinical trials, and systematic assessment of their clinical features and disease progression using machine learning could generate valuable data on patients with mixed pathologies and improve our understanding of how to effectively treat these complex cases.

Gait, balance, and physical performance as markers of early Alzheimer's disease and related dementia risk

BACKGROUND

Declining physical functionality is an indicator of cognitive impairment, distinguishing normal cognition (NC) from dementia. Whether this extends to pre-dementia stages is unclear.

OBJECTIVE

Assess physical performance patterns, evaluate relationships with imaging biomarkers, and identify specific measures distinguishing NC, subjective cognitive decline (SCD) and mild cognitive impairment (MCI).

METHODS

Group differences (78 NC, 35 SCD, and 41 MCI) in physical function (global function, balance, gait speed, step length, single leg support) were evaluated with logistic regression while distinguishing between MCI due-to-AD and MCI due-to-vascular etiology. Relationships with imaging biomarkers (cortical atrophy score, white matter hyperintensities volumes) were analyzed with ANCOVA.

RESULTS

Participants were 68.6 ± 9.3 years old, had 16.2 ± 3.0 years of education, and 23% were ethnoracial minorities. Physical performance distinguished MCI from NC and SCD. Greater performance on the Mini Physical Performance Test (mini PPT) and balance were associated with lower odds of being SCD versus NC (ORmini PPT = 0.73; 95% CI:0.56-0.97; ORbalance = 0.35, 95%CI:0.16-0.80). AD etiology accounted for most group differences in physical performance versus vascular etiology. Consistent associations between biomarkers, physical performance, and cognition were found.

CONCLUSIONS

Findings suggest that: 1) changes in mini PPT performance and balance may help detect cognitive impairments, as early as the SCD stage; 2) changes in gait speed, gait cycle parameters, and Timed Up-and-Go may indicate more significant cognitive impairment; 3) neuronal loss is linked to subtle changes in physical functionality as early as SCD. Physical performance may be a valuable tool in early dementia detection in clinical settings and could identify targets for early intervention.

Alzheimer's disease plasma biomarkers and physical functioning in a diverse sample of adults

INTRODUCTION

The relationship between Alzheimer's disease (AD) plasma biomarkers, and physical functioning (PF) across diverse races and ethnicities remains unclear. This study aims to explore this association in an ethno-racially diverse sample of cognitively unimpaired community-dwelling adults.

METHODS

Data clinical examinations, neuropsychological tests, blood draws, and PF exams (Timed Up and Go [TUG] and Short Physical Performance Battery [SPPB]) were analyzed. Multivariable linear regressions assessed the association between PF and AD plasma biomarkers (amyloid beta [Aβ]40, Aβ42, total tau [t-tau], neurofiliament light chain [NfL]).

RESULTS

The sample (n = 2358; mean age 64.7 years; 65.9% female), was 20% African American, 41.9% non-Hispanic White, and 38.1% Hispanic. Findings indicate that worse PF is linked to higher biomarker levels (p < 0.05). Associations differed by race and ethnicity group. TUG time was associated (p < 0.05) with Aβ40, Aβ42, and tau among non-Hispanic Whites, whereas SPPB scores were associated (p < 0.05) with t-tau and NfL among African Americans.

DISCUSSION

PF, ethnic/racial, and plasma AD biomarker data should be used to aid in developing risk profiles for neurodegenerative diseases.

HIGHLIGHTS

Alzheimer's disease (AD) biomarkers are associated with physical functioning (PF) Ethno-racial variation exists in AD biomarker and PF associations Race and ethnicity should considered when assessing neurodegenerative disease risk.

Feasibility of Using a Novel, Multimodal Motor Function Assessment Platform With Machine Learning to Identify Individuals With Mild Cognitive Impairment

INTRODUCTION

Early identification of clinical conditions associated with Alzheimer disease and related dementias (ADRD) is vital for intervention. One promising early detection method is the use of instrumented assessment to identify subtle motor declines associated with ADRD. This pilot study sought to establish the feasibility of building a machine learning model to identify individuals with mild cognitive impairment (MCI) using motor function data obtained from an inexpensive, portable device.

METHODS

Our novel, multimodal motor function assessment platform integrates a depth camera, forceplate, and interface board. Healthy older adults (n=28) and older adults with MCI (n=19) were assessed during static balance, gait, and sit-to-stand activities in both single- and dual-task conditions. Three machine learning models (ie, support vector machine, decision trees, and logistic regression) were trained and tested with the goal of classification of MCI.

RESULTS

Our best model was decision trees, which demonstrated an accuracy of 83%, a sensitivity of 0.83, a specificity of 1.00, and an F1 score of 0.83. The top features were extracted and ranked on importance.

DISCUSSION

This study demonstrates the feasibility of building a machine learning model capable of identifying individuals with mild cognitive impairment using motor function data obtained with a portable, inexpensive, multimodal device.

Dementia with Lewy bodies and gait neural basis: a cross-sectional study

BACKGROUND

Dementia with Lewy Bodies (DLB) is responsible for cognitive-behavioural disorders but also for gait disorders. The latter are thought to be related to parkinsonism, but the neural bases of these disorders are not well known, especially in the early stages. The aim of this study was to investigate by volumetric Magnetic Resonance Imaging the neuronal basis of gait disorders in DLB patients, compared to Healthy Elderly Controls and Alzheimer's Disease patients.

METHODS

Clinical examination with motor assessment including 10-meter walking speed, one-leg balance and Timed Up and Go test, a comprehensive neuropsychological evaluation and 3D brain Magnetic Resonance Imaging were performed on 84 DLB patients, 39 Alzheimer's Disease patients and 22 Healthy Elderly Controls. We used Statistical Parametric Mapping 12 to perform a one-sample t-test to investigate the correlation between each gait score and gray matter volume (P ≤ 0.05 corrected for family-wise error).

RESULTS

We found a correlation for DLB patients between walking speed and gray matter decrease (P < 0.05, corrected for family-wise error) in caudate nuclei, anterior cingulate cortex, mid-cingulate cortex, hippocampi, supplementary motor area, right cerebellar cortex and left parietal operculum. We found no correlation with Timed Up and Go test and one-leg balance.

CONCLUSION

Gait disorders are underpinned by certain classical regions such as the cerebellum and the supplementary motor area. Our results suggest there may be a motivational and emotional component of voluntary gait in DLB subjects, underpinned by the cingulate cortex, a spatial orientation component, underpinned by hippocampi and suggest the involvement of brain processing speed and parkinsonism, underpinned by the caudate nuclei.

TRIAL REGISTRATION

The study protocol has been registered on ClinicalTrials.gov. (NCT01876459) on June 12, 2013.

Classification of Mild Cognitive Impairment and Alzheimer's Disease Using Manual Motor Measures

INTRODUCTION

Manual motor problems have been reported in mild cognitive impairment (MCI) and Alzheimer's disease (AD), but the specific aspects that are affected, their neuropathology, and potential value for classification modeling is unknown. The current study examined if multiple measures of motor strength, dexterity, and speed are affected in MCI and AD, related to AD biomarkers, and are able to classify MCI or AD.

METHODS

Fifty-three cognitively normal (CN), 33 amnestic MCI, and 28 AD subjects completed five manual motor measures: grip force, Trail Making Test A, spiral tracing, finger tapping, and a simulated feeding task. Analyses included (1) group differences in manual performance; (2) associations between manual function and AD biomarkers (PET amyloid β, hippocampal volume, and APOE ε4 alleles); and (3) group classification accuracy of manual motor function using machine learning.

RESULTS

Amnestic MCI and AD subjects exhibited slower psychomotor speed and AD subjects had weaker dominant hand grip strength than CN subjects. Performance on these measures was related to amyloid β deposition (both) and hippocampal volume (psychomotor speed only). Support vector classification well-discriminated control and AD subjects (area under the curve of 0.73 and 0.77, respectively) but poorly discriminated MCI from controls or AD.

CONCLUSION

Grip strength and spiral tracing appear preserved, while psychomotor speed is affected in amnestic MCI and AD. The association of motor performance with amyloid β deposition and atrophy could indicate that this is due to amyloid deposition in and atrophy of motor brain regions, which generally occurs later in the disease process. The promising discriminatory abilities of manual motor measures for AD emphasize their value alongside other cognitive and motor assessment outcomes in classification and prediction models, as well as potential enrichment of outcome variables in AD clinical trials.

Reliability and minimal detectable change of the Short Physical Performance Battery in older adults with mild cognitive impairment

OBJECTIVES

Reliability of the Short Physical Performance Battery (SPPB) are rarely examined among older adults with mild cognitive impairment (MCI). This study aimed to investigate the test-retest reliability and minimal detectable change (MDC) of the SPPB in older adults with MCI.

METHODS

Participants included 100 older adults with MCI. The SPPB was assessed with the first 2 assessments separated by a 20-min interval and the third separated by a 1-week interval. The intraclass correlation coefficient (ICC) and MDC values were estimated.

RESULTS

The intraday ICC was 0.73 for the SPPB score, 0.90 for the 4-m walk time (4mwt), and 0.95 for the 5-times chair stand time (5cst); the corresponding interday ICC values were 0.76, 0.89, and 0.91, respectively. The MDC values ranged from 1.1 to 1.2 for the SPPB score, from 0.77 to 0.80 s for the 4mwt, and from 1.32 to 1.77 for the 5cst.

CONCLUSIONS

The SPPB had satisfactory reliability among older adults with MCI. The test-retest reliability of the SPPB is sufficient (>0.7) for group comparisons. Moreover, the test-retest reliability for the 4mwt and 5cst subscale performances is acceptable (> 0.9) for individual-level measurements over time.

Physical Activity Behavior and Its Association With Global Cognitive Function Three Months After Stroke: The Nor-COAST Study†

OBJECTIVE

The purposes of this study were to determine the association between physical activity (PA) behavior and global cognitive function 3 months after stroke and to explore the role of physical capacity as a mediating factor.

METHODS

Participants with stroke were successively recruited at 5 different hospitals in Norway. PA was measured using accelerometers, with a follow-up period of 7 consecutive days, and global cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). The general pattern of PA and the percentage of participants adhering to World Health Organization PA recommendations (at least 150 minutes of moderate-intensity aerobic PA per week) were investigated using descriptive statistics. Multiple regression and mediator analyses were used to examine the relationship between PA behavior and MoCA scores; physical capacity, measured with the Short Physical Performance Battery, served as the mediating variable.

RESULTS

A total of 193 women (42.6%) and 260 men (57.4%) with a median age of 73.7 years (25th and 75th percentiles = 65.8 and 80.4, respectively) and a median MoCA score of 25 points (25th and 75th percentiles = 22 and 27, respectively) were included. Mean total time spent walking at moderate intensity was 251.7 (SD = 164.6) min/wk (mean bout length = 20.9 [SD = 7.3] seconds), which indicated 69.3% adherence to World Health Organization guidelines. With each point decrease in the MoCA score, there was an expected 8.6% increase in the odds of nonadherence to PA recommendations. Physical capacity was identified as an important mediating factor, explaining the strength of the association between cognition and PA behavior.

CONCLUSIONS

In contrast to previous research, in the present study, most participants adhered to the updated global PA guidelines. However, people who had survived stroke and had reduced cognitive function were at higher risk of inactivity, an association mediated by physical capacity.

IMPACT

A better understanding of the association between cognition and PA behavior after stroke might help for developing more targeted early-onset interventions.

Factors Affecting Physical Activity in People with Dementia: A Systematic Review and Narrative Synthesis

Physical activity (PA) has positive effects on the physical and cognitive functioning of people with dementia. Knowledge about what limits and stimulates people with dementia to participate in PA is essential to promote effective PA implementation and enhance PA levels. Previous reviews primarily included opinion-based studies, using data from interviews, focus groups or dyads. By including implementation studies, we aimed to elaborate on previous reviews by identifying new barriers to PA and new facilitators and motivators for PA. We conducted systematic searches in Pubmed, PsychInfo and Web of Science for studies published up to the 21st of September 2021. Search terms were related to the population of people with dementia, PA interventions and implementation outcomes. Studies were included if PA participation was investigated during actual PA implementation. No restrictions were made regarding study design, date of publication, PA type or outcome measures. Studies not implementing PA or not evaluating the implementation were excluded. Based on 13 empirical studies, we identified 35 barriers, 19 facilitators and 12 motivators. Of these, 21 barriers, 11 facilitators and 4 motivators were not identified by previous reviews. New factors are related to the support for people with dementia from informal and formal caregivers, e.g., revealing the importance of a trusting relationship. Furthermore, support for staff from the institution or an external party is needed to overcome doubts about PA, for example, related to safety and effects. New factors also suggested specific recommendations for the content and organization of the PA intervention, for instance, related to how to give instructions. Overall, factors affecting PA identified with opinion-based or implementation studies are complementary. Our extended overview shows the complexity of PA implementation and may help to personalize PA, develop implementation strategies, facilitate actual PA implementation and free up resources needed for effective implementation.

Prevalence of malnutrition among older adults in a population-based study - the HUNT Study

BACKGROUND

Malnutrition is common in older adults and is associated with increased morbidity and mortality rates.

AIM

The aim of the study is to describe the prevalence of malnutrition based on low BMI, involuntary weight loss, and reduced food intake, in a Norwegian population of community-dwelling older adults and older adults living in nursing homes.

METHODS

This population-based study is part of the fourth wave of the Trøndelag Health Study (HUNT4) and includes participants ≥70 years from the HUNT4 70+ cohort. The HUNT4 70+ cohort consist of 9930 (response rate 51.2%) participants. In the current study 8127 older people had complete dataset for inclusion in the analyses. Participants completed a self-report questionnaire and standardised interviews and clinical assessments at field stations, in participants' homes or at nursing homes. Malnutrition was defined using the following criteria: low BMI, involuntary weight loss and severely reduced food intake. The standardised prevalence of malnutrition was estimated using inverse probability weighting (IPW) with weights for sex, age and education of the total population in the catchment area of HUNT.

RESULTS

Of the 8127 included participants, 7671 (94.4%) met at field stations, 356 (4.4%) were examined in their home, and 100 (1.2%) in nursing homes. In total, 14.3% of the population were malnourished based on either low BMI, weight loss, or reduced food intake, of which low BMI was the most frequently fulfilled criterion. The prevalence of malnutrition was less common among men than among women (10.1 vs 18.0%, p < 0.001), also after adjustment for age (OR 0.53, 95% confidence interval (CI) 0.46-0.61). The prevalence increased gradually with increasing age and the regression analysis adjusted for sex showed that for each year increase in age the prevalence of malnutrition increased with 4.0% (OR 1.04, 95% CI 1.03-1.05). The prevalence was higher both among older adults examined in their homes (26.4%) and residents in nursing home (23.6%), as compared to community-dwelling older adults who met at field stations (13.5%).

CONCLUSION

The prevalence of malnutrition is high in the older population. Special attention on prevention and treatment of malnutrition should be given to older women, the oldest age groups, and care-dependent community-dwelling older adults and nursing home residents.

Association of Lifelong Cognitive Reserve with Dementia and Mild Cognitive Impairment among Older Adults with Limited Formal Education: A Population-Based Cohort Study

INTRODUCTION

Early-life educational attainment contributes to cognitive reserve (CR). We investigated the associations of lifelong CR with dementia and mild cognitive impairment (MCI) among older people with limited formal education.

METHODS

This population-based cohort study included 2,127 dementia-free participants (≥60 years; 59.4% women; 81.5% with no or elementary school) who were examined at baseline (August-December 2014) and follow-up (March-September 2018). Lifelong CR score at baseline was generated from six lifespan intellectual factors. Dementia, MCI, and their subtypes were defined according to the international criteria. Data were analyzed using Cox proportional-hazards models.

RESULTS

During the total of 8,330.6 person-years of follow-up, 101 persons were diagnosed with dementia, including 74 with Alzheimer's disease (AD) and 26 with vascular dementia (VaD). The high (vs. low) tertile of lifelong CR score was associated with multivariable-adjusted hazards ratios (95% confidence interval) of 0.28 (0.14-0.55) for dementia and 0.18 (0.07-0.48) for AD. The association between higher CR and reduced AD risk was significant in people aged 60-74 but not in those aged ≥75 years (p for interaction = 0.011). Similarly, among MCI-free people at baseline (n = 1,635), the high (vs. low) tertile of lifelong CR score was associated with multivariable-adjusted hazard ratios of 0.51 (0.38-0.69) for MCI and 0.46 (0.33-0.64) for amnestic MCI. Lifelong CR was not related to VaD or non-amnestic MCI.

DISCUSSION

High lifelong CR is associated with reduced risks of dementia and MCI, especially AD and amnestic MCI. It highlights the importance of lifelong CR in maintaining late-life cognitive health even among people with no or limited education.

What Tools Can We Use to Screen for Fall Risk in Older Patients with Mild Cognitive Impairment? Findings from the MEMENTO Cohort

OBJECTIVES

Identifying risk factors for falls can improve outcomes in older patients without cognitive decline. Yet this has not been demonstrated in older people with mild cognitive impairment (MCI). We therefore sought to better identify risk factors for falls in this particular group.

DESIGN

The analysis was conducted on the MEMENTO cohort, which is a large, French, prospective cohort.

SETTING AND PARTICIPANTS

We included older people (>65 years old) with MCI (defined from neuropsychological scores) and a Short Physical Performance Battery (SPPB) score at baseline.

METHODS

Fallers were defined as participants having fallen at least once during the study's 2-year follow-up period. We compared clinical, neuropsychological, and biological data at baseline in fallers vs nonfallers. Additional analyses were performed on the following subgroups: women, men, people aged ≥75 years.

RESULTS

Of the 1416 people included in our study, 194 (13.5%) fell at least once. A bivariate analysis showed that fallers were older, predominantly women, less independent in activities of daily living, and more apathetic. Fallers performed less well in executive function, balance, and gait tests. In a multivariable analysis, only age, gender, the number of limitations in instrumental activities of daily living, and living alone were significantly associated with falls. In a multivariable analysis of the subgroup of oldest patients and of the subgroup of men, executive function was significantly worse in fallers than in nonfallers.

CONCLUSION AND IMPLICATIONS

Our results demonstrate that easily attainable risk factors can be used to identify individuals with MCI with a higher risk of falls and for whom prevention could be beneficial. Future studies are needed to further evaluate the role of mild executive dysfunction in certain subgroups, such as men and oldest patients.

The association between cognitive impairment, gait speed, and Walk ratio

Background

Gait speed has been found to be associated with cognitive function. However, gait speed is an unspecific measure that may not be informative about gait patterns. The Walk ratio (step length divided by step frequency) can be measured without specialized equipment, and has been suggested as an indicator of central gait control. However, the association with cognitive function is unknown.

Research question

Is there a relationship between Walk ratio and cognitive function, and gait speed and cognitive function?

Methods

This was a systematic literature review of studies where spatiotemporal gait parameters was reported in populations with cognitive impairment. The search was performed through PubMed, PEDro, AMED, Cochrane, Embase, MEDLINE, and PsycINFO. The studies had to contain either the Walk ratio, or report average step length and average step frequency. In the latter case, the average step length was divided by the average step frequency. The studies also had to report gait speed and the minimal mental state examination (MMSE). Studies testing patients on treadmills or that did not state the exclusion of patients with neurologic or orthopedic diseases, possible affecting gait ability, were excluded.

Results

A total of 24 studies were included, consisting of 909 patients with cognitive impairment and 4,108 healthy controls. The patient group had a lower Walk ratio (mean difference 0.07, p ≤ 0.001) and gait speed (mean difference 0.26, p ≤ 0.001) than the healthy controls. Using linear regression models, we found an association between the MMSE and the Walk ratio (R² = 0.29, p < 0.001) and gait speed (R² = 0.41, p < 0.001) in separate, unadjusted models. In a final model with Walk ratio, gait speed and age, Walk ratio was not significantly associated with MMSE, while gait speed was.

Significance

Our results suggest that preferred gait speed may be preferable to the Walk ratio when assessing older adults with cognitive impairment.

Hearing threshold and physical performance in older people: a cross-sectional study from the HUNT4 cohort

PURPOSE

To evaluate the association between increased hearing loss and reduced physical performance in older people.

METHODS

Cross-sectional population-based study using data from the fourth wave of the Trøndelag Health Survey (HUNT4) in Norway. Data were obtained from the subproject HUNT4 Hearing which collected audiometric data of people > 70 years (N = 13,197). Analyses were performed on all participants who had completed audiometry and measured balance using the Short Physical Performance Battery (SPPB), which was scored from 0 (worst score) to 12. The hearing threshold was expressed as a pure tone average (PTA). Associations between the hearing threshold for the best and worst ear and physical performance were analyzed by linear regression models adjusted for age, sex, education, diabetes, and cardiovascular disease. Hearing threshold was indicated with steps of 10 dB.

RESULTS

Of 13,197 eligible participants, 4101 who completed audiometry and SPPB (52.3% women. mean age 76.3 years) were included. The analyses revealed an association between reduced SPPB and increased hearing threshold in the best ear (b = - 0.296; 95% CI - 0.343 to - 0. 249; P < 0.001) and the worst ear (b = - 0.229; 95% CI - 0.270 to - 0.189; P < 0.001).

CONCLUSIONS

In this population study, we found that the increased hearing threshold was associated to reduced physical performance as measured by SPPB. The association seemed to be strongest for the best ear. The association between hearing threshold and physical performance illustrates the importance of assessing physical performance in people with hearing loss to prevent the risk of falls and disability. The underlying causes of the associations between hearing loss and poorer physical performance are not fully understood and should be further investigated.

LEVEL OF EVIDENCE

Level 3.

The Nebulous Association between Cognitive Impairment and Falls in Older Adults: A Systematic Review of the Literature

BACKGROUND

In older people, dementia is a well-established risk factor for falls. However, the association and the causal relationship between falls and the earlier stages of cognitive impairment remains unclear. The purpose of the study was to review the literature data on the association between falls and cognitive impairment, no dementia, including Mild Cognitive Impairment.

METHODS

According to PRISMA guidelines, we searched five electronic databases (EMBASE, Web of Science, Medline, CINAHL, and PsychINFO) for articles published between January 2011 and August 2022 on observational studies of older people with a cognitive assessment and/or cognitive impairment diagnosis and a recording of falls. Their quality was reviewed according to the STROBE checklist.

RESULTS

We selected 42 of the 4934 initially retrieved publications. In 24 retrospective studies, a statistically significant association between falls and cognitive status was found in only 15 of the 32 comparisons (47%). Of the 27 cross-sectional analyses in prospective studies, only eight (30%) were positive and significant. We counted four longitudinal analyses, half of which suggested a causal relationship between falls and cognitive impairment. The investigational methods varied markedly from one study to another.

CONCLUSION

It is still not clear whether falls are associated with cognitive impairment, no dementia. Data in favor of a causal relationship are scarce. Further studies are needed to clarify their relationship.

Plasma Biomarkers of Alzheimer's Disease Are Associated with Physical Functioning Outcomes Among Cognitively Normal Adults in the Multiethnic HABS-HD Cohort

In this study, we examined the link between plasma Alzheimer's disease (AD) biomarkers and physical functioning outcomes within a community-dwelling, multiethnic cohort. Data from 1 328 cognitively unimpaired participants (n = 659 Mexican American and n = 669 non-Hispanic White) from the ongoing Health & Aging Brain Study-Health Disparities (HABS-HD) cohort were examined. Plasma AD biomarkers (amyloid beta [Aβ]40, Aβ42, total tau [t-tau], and neurofilament light chain [NfL]) were assayed using the ultra-sensitive Simoa platform. Physical functioning measures were the Timed Up and Go (TUG) and the Short Physical Performance Battery (SPPB). Cross-sectional linear regression analyses revealed that plasma Aβ 40 (p < .001), Aβ 42 (p = .003), and NfL (p < .001) were each significantly associated with TUG time in seconds. Plasma Aβ 40 (p < .001), Aβ 42 (p < .001), t-tau (p = .002), and NfL (p < .001) were each significantly associated with SPPB Total Score. Additional analyses demonstrate that the link between plasma AD biomarkers and physical functioning outcomes were strongest among Mexican Americans. Plasma AD biomarkers are receiving a great deal of attention in the literature and are now available clinically including use in clinical trials. The examination of AD biomarkers and physical functioning may allow for the development of risk profiles, which could stratify a person's risk for neurodegenerative diseases, such as AD, based on plasma AD biomarkers, physical functioning, ethnicity, or a combination of these measures prior to the onset of cognitive impairment.

Relationship between consistent subjective cognitive decline and occurrence of falls six months later

PURPOSE

To examine the association between consistent subjective cognitive decline and fall occurrence six months later.

METHOD

A cohort study was conducted at two time points in community-dwelling older adults. The first survey was conducted from May to July 2020 and the second from November 2020 to January 2021. Older adults without missing data who had not fallen during the past year were analyzed. The questionnaire included sociodemographic data, a questionnaire for medical checkup of older adults, and a frailty screening index. We divided the participants into three groups according to the occurrence of subjective cognitive decline (SCD): 1) no SCD (did not complain of SCD at both time points), 2) unstable SCD (complained of SCD once), and 3) consecutive SCD (consistently complained of SCD). Multiple logistic regression analysis was used to examine the association between fall occurrence and SCD. Fall occurrences were obtained from the second survey.

RESULTS

In total, 322 participants were included in the analysis. The numbers of patients with no SCD, unstable SCD, and consecutive SCD were 226 (70.2%), 61 (19.0%), and 35 (10.9%), respectively. In the second survey, the number of falls was 26 (8.1%). Multiple logistic regression analysis showed that consecutive SCD was associated with fall occurrence, even after adjusting for age, sex, comorbidity, cohabitants, and frailty status (OR:3.143, 95% CI:1.076-9.388); however, unstable SCD was not (OR:2.348, 95% CI:0.816-6.468).

CONCLUSION

Consistent complaints of SCD were associated with the occurrence of falls. We highlighted the importance of evaluating SCD over time when considering falls.

Sit to stand muscle power reference values and their association with adverse events in Colombian older adults

Recently, a valid method to assess lower-body muscle power based on a sit-to-stand field test (STS) has been published. Our study aimed to describe lower-body muscle power in older individuals aged ≥ 60 years and examine the relationship of muscle weakness with adverse events according to gender- and age-specific muscle weakness cut-off points. A total of 3689 Colombian older adults (57.6% women, age 69.1 ± 6.9 years) from the 2015 Survey on Health, Well-Being, and Aging in Latin America and the Caribbean (SABE) participated in this study. Lower-body muscle power normalized to body mass was estimated by the five-repetitions STS test. Anthropometric, physical performance and clinical characteristics were collected. Age-specific percentiles using the LMS method, cut-off points and association with adverse events were calculated. Lower-body muscle power was greater in men than among women (2.2 ± 0.7 vs. 1.6 ± 0.5 W·kg⁻¹, respectively; p < 0.001) at all ages. Muscle power ranked in the 50th percentile between 2.38 and 1.30 W·kg⁻¹ in men, whereas women ranked between 1.79 and 1.21 W·kg⁻¹. According to the cut-off points, lower-limb muscle power < 1 standard deviation  in men was associated with having dynapenia, poor gait speed, cognitive impairment and mental, visual, hearing and memory problems. While, women were associated with having sarcopenia, dynapenia, poor gait speed, cognitive impairment, mental, hearing and memory problems, dementia and hospitalizations of > 24 h in the last year. Overall, participants with poor lower-limb muscle power had a significantly higher risk of adverse events [in men: odds ratio (OR) = 1.51, 95% confidence interval (CI) = 1.19–1.91, p < 0.001; in women: OR = 1.52, 95% CI = 1.27–1.87, p = 0.001] than their stronger counterparts. This study is the first to describe lower-limb muscle power values and cut-off points among a nationally representative sample of Colombian older adults. In men, 7 of the 14 adverse events studied were associated with lower muscle strength, whereas in women, it was 9 of the 14 adverse events.

Pathological Gait Signatures of Post-stroke Dementia With Toe-Off and Heel-to-Ground Angles Discriminate From Alzheimer's Disease

Given the limited power of neuropsychological tests, there is a need for a simple, reliable means, such as gait, to identify mild dementia and its subtypes. However, gait characteristics of patients with post-stroke dementia (PSD) and Alzheimer’s disease (AD) are unclear. We sought to describe their gait signatures and to explore gait parameters distinguishing PSD from post-stroke non-dementia (PSND) and patients with AD. We divided 3-month post-stroke patients into PSND and PSD groups based on the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and the activity of daily living (ADL). Thirty-one patients with AD and thirty-two healthy controls (HCs) were also recruited. Ten gait parameters in one single and two dual-task gait tests (counting-backward or naming-animals while walking) were compared among the groups, with adjustment for baseline demographic covariates and the MMSE score. The area under the receiver operating characteristic curve (AUC) was used to identify parameters discriminating PSD from individuals with PSND and AD. Patients with PSD and patients with AD showed impaired stride length, velocity, stride time, and cadence while patients with PSD had altered stance and swing phase proportions (all p ≤ 0.01, post hoc). Patients with AD had smaller toe-off (ToA) and heel-to-ground angles (HtA) (p ≤ 0.01) than HCs in dual-task gait tests. Individuals with PSD had a shorter stride length, slower velocity, and altered stance and swing phase percentages in all tests (p ≤ 0.01), but a higher coefficient of variation of stride length (CoV_SL) and time (CoV_ST) only in the naming animals-task gait test (p ≤ 0.001) than individuals with PSND. ToA and HtA in the naming animals-task gait test were smaller in individuals with AD than those with PSD (p ≤ 0.01). Statistical significance persisted after adjusting for demographic covariates, but not for MMSE. The pace and the percentage of stance or swing phase in all tests, CoV_ST in the dual-task paradigm, and CoV_SL only in the naming animals-task gait test (moderate accuracy, AUC > 0.700, p ≤ 0.01) could distinguish PSD from PSND. Furthermore, the ToA and HtA in the naming animals-task gait paradigm discriminated AD from PSD (moderate accuracy, AUC > 0.700, p ≤ 0.01). Thus, specific gait characteristics could allow early identification of PSD and may allow non-invasive discrimination between PSD and AD, or even other subtypes of dementia.