Gait and posture impairment, parkinsonism and cognitive decline in older people

Walking Step Monitoring with a Millimeter-Wave Radar in Real-Life Environment for Disease and Fall Prevention for the Elderly

We studied the use of a millimeter-wave frequency-modulated continuous wave radar for gait analysis in a real-life environment, with a focus on the measurement of the step time. A method was developed for the successful extraction of gait patterns for different test cases. The quantitative investigation carried out in a lab corridor showed the excellent reliability of the proposed method for the step time measurement, with an average accuracy of 96%. In addition, a comparison test between the millimeter-wave radar and a continuous-wave radar working at 2.45 GHz was performed, and the results suggest that the millimeter-wave radar is more capable of capturing instantaneous gait features, which enables the timely detection of small gait changes appearing at the early stage of cognitive disorders.

Association between Motor Signs and Cognitive Performance in Cognitively Unimpaired Older Adults: A Cross-Sectional Study Using the NACC Database

Aiming to examine whether specific motor signs are associated with worse performance in specific cognitive domains among cognitively unimpaired (CU) individuals, we performed a cross-sectional analysis of data from the baseline evaluations of older, CU participants from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set. In total, 8149 CU (≥60 years) participants were included. Of these, 905 individuals scored ≥ 2 on at least one of the motor domains of the Unified Parkinson's Disease Rating Scale part III (UPDRSIII). Cognitively impaired individuals, participants with psychiatric disorders and/or under treatment with antipsychotic, anxiolytic, sedative or hypnotic agents were excluded. Nine motor signs were examined: hypophonia, masked facies, resting tremor, action/postural tremor, rigidity, bradykinesia, impaired chair rise, impaired posture/gait and postural instability. Their association with performance on episodic memory, semantic memory, language, attention, processing speed or executive function was assessed using crude and adjusted linear regression models. Individuals with impaired chair rise had worse episodic memory, semantic memory, processing speed and executive function, while those with bradykinesia had worse language, processing speed and executive function. Sensitivity analyses, by excluding participants with cerebrovascular disease or PD, or other Parkinsonism, produced similar results with the exception of the relationship between bradykinesia and language performance.

Motoric Cognitive Risk Syndrome: Symptoms, Pathology, Diagnosis, and Recovery

The motoric cognitive risk (MCR) syndrome is a pre-dementia condition, marked by the enhanced risk for Alzheimer's disease (AD) and vascular dementia, together with falls, disability, and abnormal movements. The research studies revealed the distinct neurological and non-neurological clinical gait irregularities during dementia and accelerated functional decline, such as postural and balance impairments, memory loss, cognitive failure, and metabolic dysfunctions. The disabling characteristics of MCR comprise altered afferent sensory and efferent motor responses, together with disrupted visual, vestibular, and proprioceptive components. The pathological basis of MCR relates with the frontal lacunar infarcts, white matter hyperintensity (WMH), gray matter atrophy in the pre-motor and pre-frontal cortex, abnormal cholinergic functioning, inflammatory responses, and genetic factors. Further, cerebrovascular lesions and cardiovascular disorders exacerbate the disease pathology. The diagnosis of MCR is carried out through neuropsychological tests, biomarker assays, imaging studies, questionnaire-based evaluation, and motor function tests, including walking speed, dual-task gait tests, and ambulation ability. Recovery from MCR may include cognitive, physical, and social activities, exercise, diet, nutritional supplements, symptomatic drug treatment, and lifestyle habits that restrict the disease progression. Psychotherapeutic counseling, anti-depressants, and vitamins may support motor and cognitive improvement, primarily through the restorative pathways. However, an in-depth understanding of the association of immobility, dementia, and cognitive stress with MCR requires additional clinical and pre-clinical studies. They may have a significant contribution in reducing MCR syndrome and the risk for dementia. Overall, the current review informs the vital connection between gait performance and cognition in MCR and highlights the usefulness of future research in the discernment and treatment of dementiating illness.

Influences of dopaminergic system dysfunction on late-life depression

Deficits in cognition, reward processing, and motor function are clinical features relevant to both aging and depression. Individuals with late-life depression often show impairment across these domains, all of which are moderated by the functioning of dopaminergic circuits. As dopaminergic function declines with normal aging and increased inflammatory burden, the role of dopamine may be particularly salient for late-life depression. We review the literature examining the role of dopamine in the pathogenesis of depression, as well as how dopamine function changes with aging and is influenced by inflammation. Applying a Research Domain Criteria (RDoC) Initiative perspective, we then review work examining how dopaminergic signaling affects these domains, specifically focusing on Cognitive, Positive Valence, and Sensorimotor Systems. We propose a unified model incorporating the effects of aging and low-grade inflammation on dopaminergic functioning, with a resulting negative effect on cognition, reward processing, and motor function. Interplay between these systems may influence development of a depressive phenotype, with an initial deficit in one domain reinforcing decline in others. This model extends RDoC concepts into late-life depression while also providing opportunities for novel and personalized interventions.

Parkinsonism and cerebrovascular disease

The relationship between cerebrovascular disease and parkinsonism is commonly seen in everyday clinical practice but remains ill-defined and under-recognised with little guidance for the practising neurologist. We attempt to define this association and to illustrate key clinical, radiological and pathological features of the syndrome of Vascular Parkinsonism (VaP). VaP is a major cause of morbidity in the elderly associated with falls, hip fractures and cognitive impairment. Although acute parkinsonism is reported in the context of an acute cerebrovascular event, the vast majority of VaP presents as an insidious syndrome usually in the context of vascular risk factors and radiological evidence of small vessel disease. There may be an anatomic impact on basal ganglia neuronal networks, however the effect of small vessel disease (SVD) on these pathways is not clear. There are now established reporting standards for radiological features of SVD on MRI. White matter hyperintensities and lacunes have been thought to be the representative radiological features of SVD but other features such as the perivascular space are gaining more importance, especially in context of the glymphatic system. It is important to consider VaP in the differential diagnosis of Parkinson disease (PD) and in these situations, neuroimaging may offer diagnostic benefit especially in those patients with atypical presentations or refractoriness to levodopa. Proactive management of vascular risk factors, monitoring of bone density and an exercise program may offer easily attainable therapeutic targets in PD and VaP. Levodopa therapy should be considered in patients with VaP, however the dose and effect may be different from use in PD. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.

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.

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.

Effect of Mental Fatigue on Postural Sway in Healthy Older Adults and Stroke Populations

The aim of this study was to examine the effect of mental fatigue on postural sway under different sensory conditions in healthy older adults and in persons with chronic stroke (PwCS). Thirty healthy older adults (> 60 years old), randomly separated into experimental and control groups, as well as 15 PwCS participated in this study. Experimental groups were asked to stand on a force platform wearing seven inertial sensors while performing the Sensory Organization Test (SOT) under two cognitive conditions (single- and dual-task) before and after a mental fatigue task (stop-signal task for 60 min). The control group performed the same protocol before and after watching a movie for 60 min. Changes in subjective fatigue was assessed by the NASA Task Load Index and psychophysiological workload was assessed by heart rate variability (HRV). Postural sway was assessed by calculating the Jerk and root mean square (RMS) of center of mass (COM). Higher Jerk and RMS of COM (p < 0.05) were observed after the mental fatigue task in both healthy older adults and PwCS during SOT, which was not observed in the control group (p > 0.05). Additionally, postural sway increased in the three groups as the SOT conditions became more challenging. Our results indicate that mental fatigue, induced by sustained cognitive activity, can impair balance during SOT in older adult and stroke populations.

Concurrent validity of the Groningen Meander Walking and Timed Up and Go tests in older adults with dementia

Background and Purpose: The Groningen Meander Walking time (GMW-sec) test has not been clinically validated as a feasible assessment to test functional mobility skills. The purpose of this study was to determine the concurrent validity of the GMW-sec test with the Timed Up and Go (TUG) test in older adults with dementia. Methods: This study included a cross-sectional and between subjects design with one factor, which had three different levels of group. Consecutive sampling was used to recruit 145 elderly participants in dementia and senior care facilities. Participants were divided into three groups based on the result of a Mini-Mental Status Exam for Dementia Screening: 57 older adults with dementia, 25 older adults with mild cognitive impairment, and 63 healthy older adults. Results: Spearman rank order correlation showed that the TUG test had moderate association with the GMW-sec test not only in older adults with dementia (r = 0.69; p < 0.01), but also for the mild cognitive group (r = 0.63; p = 0.01) and healthy group (r = 0.47; p < 0.01). Older adults with dementia had a significant functional reduction for both GMW-sec and TUG tests compared to other two groups (p < 0.01). Discussion and Conclusion: Turning motions with the TUG test may cause similar challenges that relate to a curved walking path for the GMW-sec test in older adults with dementia. Both the TUG and GMW-sec tests could be effective approaches for screening the severity of cognitive impairment on functional mobility in people with dementia.

Day-to-Day Variability of Postural Sway and Its Association With Cognitive Function in Older Adults: A Pilot Study

Introduction: Increased variability in motor function has been observed during the initial stages of cognitive decline. However, the natural variability of postural control, as well as its association with cognitive status and decline, remains unknown. The objective of this pilot study was to characterize the day-to-day variability in postural sway in non-demented older adults. We hypothesized that older adults with a lower cognitive status would have higher day-to-day variability in postural sway. Materials and Methods: A Nintendo Wii balance board (WBB) was used to quantify postural sway in the home twice daily for 30 days in 20 non-demented, community-dwelling older adults: once under a single-task condition and once under a dual-task condition (using a daily word search task administered via a Nook tablet). Mean sway distance, velocity, area, centroidal frequency and frequency dispersion were derived from the center of pressure data acquired from the WBB. Results: Linear relationships were observed between the day-to-day variability in postural sway and cognitive status (indexed by cognitive global z-scores). More variability in time-domain postural sway (sway distance and area) and less variability in frequency-domain postural sway (centroidal sway frequency) were associated with a lower cognitive status under both the single- and dual-task conditions. Additionally, lower cognitive performance rates on the daily word search task were related to a lower cognitive status. Discussion: This small pilot study conducted on a short time scale motivates large-scale implementations over more extended time periods. Tracking longitudinal changes in postural sway may further our understanding of early-stage postural decline and its association with cognitive decline and, in turn, may aid in the early detection of dementia during preclinical stages when the utility of disease-modifying therapies would be greatest.

Motor function and incident dementia: a systematic review and meta-analysis

Background

cognitive and mobility decline are interrelated processes, whereby mobility decline coincides or precedes the onset of cognitive decline.

Objective

to assess whether there is an association between performance on motor function tests and incident dementia.

Methods

electronic database, grey literature and hand searching identified studies testing for associations between baseline motor function and incident dementia in older adults.

Results

of 2,540 potentially relevant documents, 37 met the final inclusion criteria and were reviewed qualitatively. Three meta-analyses were conducted using data from 10 studies. Three main motor domains-upper limb motor function, parkinsonism and lower limb motor function-emerged as associated with increased risk of incident dementia. Studies including older adults without neurological overt disease found a higher risk of incident dementia associated with poorer performance on composite motor function scores, balance and gait velocity (meta-analysis pooled HR = 1.94, 95% CI: 1.41, 2.65). Mixed results were found across different study samples for upper limb motor function, overall parkinsonism (meta-analysis pooled OR = 3.05, 95% CI: 1.31, 7.08), bradykinesia and rigidity. Studies restricted to older adults with Parkinson's Disease found weak or no association with incident dementia even for motor domains highly associated in less restrictive samples. Tremor was not associated with an increased risk of dementia in any population (meta-analysis pooled HR = 0.80, 95% CI 0.31, 2.03).

Conclusion

lower limb motor function was associated with increased risk of developing dementia, while tremor and hand grip strength were not. Our results support future research investigating the inclusion of quantitative motor assessment, specifically gait velocity tests, for clinical dementia risk evaluation.

The interrelationships between motor, cognitive, and language development in children with and without intellectual and developmental disabilities

It is generally agreed that cognitive and language development are dependent on the emergence of motor skills. As the literature on this issue concerning children with developmental disabilities is scarce, we examined the interrelationships between motor, cognitive, and language development in children with intellectual and developmental disabilities (IDD) and compared them to those in children without IDD. In addition, we investigated whether these relationships differ between children with different levels of cognitive delay. Seventy-seven children with IDD (calendar age between 1;0 and 9;10 years; mean developmental age: 1;8 years) and 130 typically developing children (calendar age between 0;3 and 3;6 years; mean developmental age: 1;10 years) were tested with the Dutch Bayley Scales of Infant and Toddler Development, Third Edition, which assesses development across three domains using five subscales: fine motor development, gross motor development (motor), cognition (cognitive), receptive communication, and expressive communication (language). Results showed that correlations between the motor, cognitive, and language domains were strong, namely .61 to .94 in children with IDD and weak to strong, namely .24 to .56 in children without IDD. Furthermore, the correlations showed a tendency to increase with the severity of IDD. It can be concluded that both fine and gross motor development are more strongly associated with cognition, and consequently language, in children with IDD than in children without IDD. The findings of this study emphasize the importance of early interventions that boost both motor and cognitive development, and suggest that such interventions will also enhance language development.

A statistical characterization of the finger tapping test: modeling, estimation, and applications

Sensory-motor performance is indicative of both cognitive and physical function. The Halstead-Reitan finger tapping test is a measure of sensory-motor speed commonly used to assess function as part of a neuropsychological evaluation. Despite the widespread use of this test, the underlying motor and cognitive processes driving tapping behavior during the test are not well characterized or understood. This lack of understanding may make clinical inferences from test results about health or disease state less accurate because important aspects of the task such as variability or fatigue are unmeasured. To overcome these limitations, we enhanced the tapper with a sensor that enables us to more fully characterize all the aspects of tapping. This modification enabled us to decompose the tapping performance into six component phases and represent each phase with a set of parameters having clear functional interpretation. This results in a set of 29 total parameters for each trial, including change in tapping over time, and trial-to-trial and tap-to-tap variability. These parameters can be used to more precisely link different aspects of cognition or motor function to tapping behavior. We demonstrate the benefits of this new instrument with a simple hypothesis-driven trial comparing single and dual-task tapping.

[Gait disorders in the elderly]

Gait disorders are one of the most common gerontoneurological symptoms. Falls that occasionally cause severe injuries are highly relevant consequences. A clinical neurological examination and inspectoral gait analysis are the core investigations of the diagnostic process, which yields hypotheses with respect to the impaired structures as well as to specific diagnostic measures. The supplemental motor assessment quantifies the resulting impairment of mobility and risk of falling with the help of well-established instruments. Characteristic of gait disorders in the elderly are the multifactorial causes which make the complete identification, correct prioritization and adequate treatment the biggest challenges. The therapeutic concept is multiprofessional and includes the causal treatment of underlying diseases, physiotherapeutic training programs, prescription of medical aids and nutritional interventions. Identification and modification of risk factors (including those that are iatrogenic) are of superior importance.

Locomotion, cognition and influences of nutrition in ageing

Gait and cognitive impairments in older adults can reflect the simultaneous existence of two syndromes that affect certain brain substrates and pathologies. Nutritional deficiencies, which are extremely common among elderly population worldwide, have potential to impact the existence and rehabilitation of both syndromes. Gait and cognition are controlled by brain circuits which are vulnerable to multiple age-related pathologies such as vascular diseases, inflammation and dementias that may be caused or accentuated by poor nutrition or deficiencies that lead to cognitive, gait or combined cognitive and gait impairments. The following review aims to link gait and cognitive classifications and provide an overview of the potential impact of nutritional deficiencies on both neurological and gait dysfunctions. The identification of common modifiable risk factors, such as poor nutrition, may serve as an important preventative strategy to reduce cognitive and mobility impairments and moderate the growing burden of dementia and disability worldwide.

The distribution of phosphorylated tau in spinal cords of Alzheimer's disease and non-demented individuals

Abnormal phosphorylation of the microtubule-associated protein tau develops in selected brain regions in normal aging and becomes widespread throughout the brain in Alzheimer's disease (AD). Braak and others have described the distribution of neurofibrillary tangles and deposition of abnormally phosphorylated tau (p-tau) and correlated this with the progressive cognitive dysfunction in AD. However, to date there have been no comprehensive studies examining abnormally phosphorylated tau deposition in the spinal cord as part of normal aging or AD. We investigated, using immunohistochemical methods, the presence of p-tau in the spinal cord of 46 cases with a clinicopathological diagnosis of AD as well as 37 non-demented aged (ND) individuals lacking any defined central nervous system-related clinicopathological diagnosis. We found the cervical cord segments to be the most frequently affected subdivision (96% AD versus 43% ND), followed by thoracic (69% AD versus 37% ND), lumbar (65% AD versus 27% ND), and sacral (53% AD versus 13% ND). The spinal cord was often affected at early-stage brain disease, with p-tau spinal cord immunoreactivity in 40% of subjects at Braak neurofibrillary stage I; however, there were no cases having spinal cord p-tau that did not have p-tau within the brain. As p-tau immunoreactivity is present within the spinal cords of ND as well as AD subjects, it is likely that the phosphorylation of spinal cord tau occurs in the preclinical stage of AD, prior to dementia. The presence of significant spinal cord p-tau-immunoreactive pathology has important implications for both the pathogenesis and clinical manifestations of AD.

A state-space model for finger tapping with applications to cognitive inference

Sensory-motor functions have been repeatedly linked to both cognitive and physical functions. One common test of sensory-motor performance frequently used for neuropsychological evaluation is the Halstead-Reitan finger tapping test (FTT). While this test has been normed and used extensively, the underlying sensory, motor and cognitive processes mediating tapping behavior during the test are not well understood. As a first step towards investigating the behavioral aspects manifested by these processes, we describe a state-space model for finger tapping during the FTT. This state-space model exploits quasiperiodicity to decompose tapping into a set of time-varying states corresponding to the instantaneous amplitude of the finger oscillation, the instantaneous frequency (or speed) of tapping, and a phase that keeps track of the current finger position during the cycle. We evaluate the model by showing a good fit between estimated and actual measurements, and outline an experiment that will relate features from the model to cognitive function.

Prevalence and burden of gait disorders in elderly men and women aged 60-97 years: a population-based study

Background

Although gait disorders are common in the elderly, the prevalence and overall burden of these disorders in the general community is not well defined.

Methods

In a cross-sectional investigation of the population-based Bruneck Study cohort, 488 community-residing elderly aged 60–97 years underwent a thorough neurological assessment including a standardized gait evaluation. Gait disorders were classified according to an accepted scheme and their associations to falls, neuropsychological measures, and quality of life were explored.

Results

Overall, 32.2% (95% confidence interval [CI] 28.2%–36.4%) of participants presented with impaired gait. Prevalence increased with age (p<0.001), but 38.3% (95%CI 30.1%–47.3%) of the subjects aged 80 years or older still had a normally preserved gait. A total of 24.0% (95%CI 20.4%–28.0%) manifested neurological gait disorders, 17.4% (14.3%–21.0%) non-neurological gait problems, and 9.2% (6.9%–12.1%) a combination of both. While there was no association of neurological gait disorders with gender, non-neurological gait disorders were more frequent in women (p = 0.012). Within the group of neurological gait disorders 69.2% (95%CI 60.3%–76.9%) had a single distinct entity and 30.8% (23.1%–39.7%) had multiple neurological causes for gait impairment. Gait disorders had a significant negative impact on quantitative gait measures, but only neurological gait disorders were associated with recurrent falls (odds ratio 3.3; 95%CI 1.4–7.5; p = 0.005 for single and 7.1; 2.7–18.7; p<0.001 for multiple neurological gait disorders). Finally, we detected a significant association of gait disorders, in particular neurological gait disorders, with depressed mood, cognitive dysfunction, and compromised quality of life.

Conclusions

Gait disorders are common in the general elderly population and are associated with reduced mobility. Neurological gait disorders in particular are associated with recurrent falls, lower cognitive function, depressed mood, and diminished quality of life.

RELATIONSHIP OF GAIT AND COGNITION IN THE ELDERLY

Gait and cognitive impairments in older adults mostly reflect the co-occurrence of two geriatric syndromes linked by common underlying brain substrates and pathologies. Gait control is predominately mediated by frontal subcortical circuits, which overlap with circuits controlling executive control and attention functions. These circuits are vulnerable to multiple age-related pathologies such as ischemia, inflammation, and neurodegeneration, which could ultimately cause cognitive, gait, or combined cognitive and gait impairments. The following review aims to describe various gait and cognitive classifications, gait based phenotypes, common underlying pathological processes, and provide a link between motor and cognitive impairments in an effort to predict the risk of dementia, as well as remediate impairments by applying appropriate interventions.

Mild physical impairment predicts future diagnosis of dementia of the Alzheimer's type

OBJECTIVES

To determine whether mildly impaired physical function (based on performance-based assessment) is associated with development of dementia of the Alzheimer's type (DAT) in cognitively normal older adults.

DESIGN

Longitudinal, observational study with yearly assessments of physical and cognitive function. Mean follow-up was 5 years.

SETTING

Knight Alzheimer's Disease Research Center at Washington University, St. Louis, Missouri.

PARTICIPANTS

Four hundred thirty-five cognitively normal adults aged 60 and older participating in longitudinal studies of aging.

MEASUREMENTS

Survival analyses were used to examine whether scores on the 9-item Physical Performance Test (PPT) predicted time to DAT diagnosis. Cox proportional hazards models were used to examine associations between PPT total scores and time to cognitive impairment and DAT; as well as the association between time and these events, adjusting for and simultaneously testing the effects of age, sex, education, and presence of one or more apolipoprotein (APOE) ε4 alleles.

RESULTS

During the follow-up period, 81 participants developed DAT. Participants diagnosed with DAT were older (81.0 vs 74.2, P = .001) and had worse performance on the PPT (25.5 vs 28.1, P = .009) than those who remained cognitively normal. Time to DAT diagnosis was associated with PPT total score (hazard ratio (HR) = 0.89, 95% confidence interval (CI) = 0.86-0.93, P < .001) such that time to DAT diagnosis was longer for participants with higher physical performance scores. In the adjusted analysis, PPT score significantly predicted time to DAT diagnosis (HR = 0.94, 95% CI = 0.89-0.99, P = .02).

CONCLUSION

Mild physical impairment in cognitively normal older adults is associated with subsequent development of DAT. Although the physical impairment may be sufficiently mild that it is recognized only using performance-based assessments, its presence may predate clinically detectable cognitive decline.

An assessment of neurocognitive speed in relation to frailty

OBJECTIVES

to evaluate the relationship between neurocognitive speed (NCS) and frailty; to consider how this relationship is affected by how frailty is operationalised.

DESIGN

secondary analysis of the baseline cohort of the Oxford Project To Investigate Memory and Aging (OPTIMA), a longitudinal observational cohort.

SUBJECTS

of 388 participants who underwent a comprehensive intake assessment followed by an annual follow-up for at least 3 years, data on all measures were available on 164 people.

MEASUREMENTS

NCS was defined as a combined score of <18 on the pattern comparison test (<11 is abnormal) and letter comparison test (<7 is abnormal). Frailty was defined from a modified Phenotype model, the Edmonton Frailty Scales (EFS) and a frailty index (FI); the latter two were adapted here to exclude cognitive measures.

RESULTS

in multivariate logistic (NCS as < or ≥18) and linear regression (NCS as continuous variable), only the FI (OR = 0.87) was significant (P < 0.05). When all frailty measures were included in the multivariate analysis only, FI (OR = 0.88) was significant (P < 0.05). Mini-mental Status Examination remained significantly related to NCS throughout all analysis.

CONCLUSION

NCS slows with increasing frailty as shown with the FI.

Metacognitive Performance, the Tip-of-Tongue Experience, Is Not Disrupted in Parkinsonian Patients

The present study investigated whether a form of metamemory, the tip-of-tongue phenomenon (TOT), was affected in patients with Parkinson's disease (PD). The PD patient (n = 22), age-matched elderly control (n = 22), and college student control (n = 46) groups were compared on a motor timing task and TOT measures. Motor timing was assessed using a cued hand-clapping task, whereas TOT was assessed using general knowledge questions. The results indicated that motor timing was significantly impaired in the PD group relative to both control groups. However, all of the TOT metacognitive measures: frequency, strength, and accuracy were statistically equivalent between the PD patients and elderly control groups, both of whom showed significantly better memory performance than college controls. These findings demonstrate that TOT metamemory is not compromised in PD patients, and that further insight into TOT mechanisms in PD may prove helpful in developing novel intervention strategies to enhance memory and general cognitive functions in these patients.

Frailty criteria and cognitive performance are related: data from the FIBRA study in Ermelino Matarazzo, São Paulo, Brazil

OBJECTIVES

To assess the relationship between the CHS frailty criteria (Fried et al., 2001) and cognitive performance.

DESIGN

Cross sectional and population-based.

SETTING

Ermelino Matarazzo, a poor sub district of the city of São Paulo, Brazil.

PARTICIPANTS

384 community dwelling older adults, 65 and older.

MEASUREMENTS

Assessment of the CHS frailty criteria, the Brief Cognitive Screening Battery (memorization of 10 black and white pictures, verbal fluency animal category, and the Clock Drawing Test) and the Mini-Mental State Examination (MMSE).

RESULTS

Frail older adults performed significantly lower than non-frail and pre frail elderly in most cognitive variables. Grip strength and age were associated to MMSE performance, age was associated to delayed memory recall, gait speed was associated to verbal fluency and CDT performance, and education was associated to CDT performance.

CONCLUSION

Being frail may be associated with cognitive decline, thus, gerontological assessments and interventions should consider that these forms of vulnerability may occur simultaneously.

Cognitive impairment and low physical activity are the components of frailty more strongly associated with disability

OBJECTIVE

To determine the association of the five frailty criteria from the Cardiovascular Health Study, as well as cognitive impairment, with prevalent disability for the instrumental (IADL) and basic activities of daily living (ADL).

DESIGN

Cross-sectional study of 475 community-dwelling subjects aged 70 and older, participating in the Mexican Study of Nutritional and Psychosocial Markers of Frailty.

MEASUREMENTS

Six probable frailty criteria were considered: weight loss, poor endurance, low physical activity, slowness, weakness, and cognitive impairment. The association of each component of frailty for IADL and ADL disability as main outcomes was determined constructing multivariate logistic regression analyses. Final models were adjusted by socio-demographic factors and the presence of the other five frailty components as covariates.

RESULTS

Mean age of participants was 78.1 (SD=6.2). The unadjusted results showed that each of the components of frailty, except weight loss, was associated with both IADL and ADL disability. However, after adjustment, only low physical activity [Odds ratio (OR) =3.27; 95% CI=1.56 to 6.85] and cognitive impairment (OR=2.06; 95% CI=1.04 to 4.06) remain independently associated with IADL disability. Regarding ADL disability, only a lower physical activity (OR=7.72; 95% CI=1.28 to 46.46) was associated with this outcome, whereas cognitive impairment was marginally associated but was not statistically significant (OR=5.45; 95% CI=0.91 to 32.57).

CONCLUSIONS

Cognitive impairment and low physical activity are the main contributing factors of frailty phenotype to disability. Better understanding the independent contribution of each frailty subdimension to the different adverse-health outcomes may help to provide a more adequate management of frail elderly.

Mild parkinsonian signs are associated with increased risk of dementia in a prospective, population-based study of elders

There is some evidence that mild parkinsonian signs (MPSs) are associated with increased risk of dementia, suggesting that MPS could be an early biomarker for dementia. Our aims, in a new cohort, were to determine whether (1) baseline MPS are a predictor of incident dementia and (2) there is an interaction between MPS and other baseline risk factors for dementia (i.e., the presence of both together greatly elevates the risk of dementia) was the objective. In a prospective, longitudinal study of community-dwelling elders in northern Manhattan, NY, Parkinsonian signs were rated with an abbreviated Unified Parkinson's Disease Rating Scale. Risk of incident dementia was assessed using Cox proportional hazards models. There were 1,851 participants (mean follow-up = 3.7 years). Participants with baseline MPS were twice as likely to develop dementia as participants without MPS: 16.3% versus 7.7%, unadjusted hazards ratio (HR) = 2.24 (P< 0.001), adjusted HR = 1.98 (P < 0.001). MPS were divided into three subtypes: adjusted HR(axial dysfunction) = 2.45 (P < 0.001), adjusted HR(tremor) = 2.38 (P = 0.006), and adjusted HR(rigidity) = 1.16 (P = 0.58). When MPS were treated as a continuous variable, the adjusted HR = 1.15 (P = 0.001). There were no interactions between MPS and other baseline risk factors for dementia, including gender, education, race, family history of dementia, stroke, and apolipoprotein E-e4. Baseline MPS seems to be a predictor of incident dementia. These motor signs might, therefore, serve as a useful biomarker for emerging dementia.

Aging and cognition

As we grow older, we gain knowledge and experience greater emotional balance, but we also experience memory loss and difficulties in learning new associations. Which cognitive abilities decline, remain stable or improve with age depends on the health of the brain and body as well as on what skills are practiced or challenged in everyday life. Recent research provides a growing understanding of the relationship between physical and cognitive changes across the life span and reveals ways to increase mental sharpness and avoid cognitive decline. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website.

Physical frailty is associated with incident mild cognitive impairment in community-based older persons

OBJECTIVES

To test the hypothesis that physical frailty is associated with risk of mild cognitive impairment (MCI).

DESIGN

Prospective, observational cohort study.

SETTING

Approximately 40 retirement communities across the Chicago metropolitan area.

PARTICIPANTS

More than 750 older persons without cognitive impairment at baseline.

MEASUREMENTS

Physical frailty, based on four components (grip strength, timed walk, body composition, and fatigue), was assessed at baseline, and cognitive function was assessed annually. Proportional hazards models adjusted for age, sex, and education were used to examine the association between physical frailty and the risk of incident MCI, and mixed effect models were used to examine the association between frailty and the rate of change in cognition.

RESULTS

During up to 12 years of annual follow-up, 305 of 761 (40%) persons developed MCI. In a proportional hazards model adjusted for age, sex, and education, physical frailty was associated with a high risk of incident MCI, such that each one-unit increase in physical frailty was associated with a 63% increase in the risk of MCI (hazard ratio=1.63; 95% confidence interval=1.27-2.08). This association persisted in analyses that required MCI to persist for at least 1 year and after controlling for depressive symptoms, disability, vascular risk factors, and vascular diseases. Furthermore, a higher level of physical frailty was associated with a faster rate of decline in global cognition and five cognitive systems (episodic memory, semantic memory, working memory, perceptual speed, and visuospatial abilities).

CONCLUSION

Physical frailty is associated with risk of MCI and a rapid rate of cognitive decline in aging.

Relationship between clinical phenotypes and cognitive impairment in Parkinson's disease (PD)

Most patients with idiopathic PD (IPD) show variable degrees of cognitive decline. The purpose of this study was to evaluate the relationship between the predominant motor symptom at the time of disease onset and the level of cognitive function in patients with IPD. A total of 159 patients with IPD were enrolled in this study. The patients' initial motor symptoms were classified into three types: tremor-dominant (TD), bradykinesia and rigidity-dominant (BRD), gait and postural instability-dominant (GPD). Disease severity was rated according to the Hoehn-Yahr classification (H&Y stage). Overall cognitive status was evaluated using the Korean versions of the Mini-Mental State Examination (K-MMSE) and the Modified Mini-Mental State (3MS) tests. The GPD group showed the lowest scores of the K-MMSE/3MS, and the patients with TD showed the best performance in the cognitive analysis (p<0.05). The patients who were older at disease onset showed worse cognitive performance than those the patients who were younger at disease onset (p<0.05). There was no difference in cognitive status according to H&Y stages. The accurate classification of initial motor symptoms and the detailed history, including the exact onset age of IPD, may allow us to predict cognitive decline in IPD.

Healthy cognitive aging and leisure activities among the oldest old in Japan: Takashima study

BACKGROUND

Little is known regarding the normative levels of leisure activities among the oldest old and the factors that explain the age-associated decline in these activities.

METHODS

The sample included 303 cognitively intact community-dwelling elderly persons with no disability in Activities of Daily Living (ADL) and minimal dependency in Instrumental ADL (IADL) in Shiga prefecture, Japan. We examined (i) the nature and frequency of leisure activities, comparing the oldest old versus younger age groups; (ii) factors that explain the age-associated differences in frequencies of engagement in these activities; and (iii) domain-specific cognitive functions associated with these activities, using three summary index scores: physical and nonphysical hobby indexes and social activity index.

RESULTS

The oldest old (85 years old or older) showed significantly lower frequency scores in all activity indexes, compared with the youngest old (age 65-74 years). Gait speed or overall mobility consistently explained the age-associated reduction in levels of activities among the oldest old, whereas vision or hearing impairment and depressive symptoms explained only the decline in social activity. Frequency of engagement in nonphysical hobbies was significantly associated with all cognitive domains examined.

CONCLUSIONS

Knowing the factors that explain age-associated decline in leisure activities can help in planning strategies for maintaining activity levels among elderly persons.