Equilibrium and limb coordination in mild cognitive impairment and mild Alzheimer's disease

Enhancing Minds in Motion® as a virtual program delivery model for people living with dementia and their care partners

The Alzheimer Society of Ontario's Minds in Motion (MiM) program improves physical function and well-being of people living with dementia (PLWD) and their care partners (CP) (Regan et al., 2019). With the COVID-19 pandemic, there was an urgent need to transition to a virtual MiM that was similarly safe and effective. The purpose of this mixed methods study is to describe the standardized, virtual MiM and evaluate its acceptability, and impact on quality of life, and physical and cognitive activity of participants. Survey of ad hoc virtual MiM practices and a literature review informed the design of the standardized MiM program: 8 weeks of weekly 90-minute sessions that included 45-minutes of physical activity and 45-minutes of cognitive stimulation in each session. Participants completed a standardized, virtual MiM at one of 6 participating Alzheimer Societies in Ontario, as well as assessments of quality of life, physical and cognitive activity, and program satisfaction pre- and post-program. In all, 111 PLWD and 90 CP participated in the evaluation (average age of 74.6±9.4 years, 61.2% had a college/university degree or greater, 80.6% were married, 48.6% of PLWD and 75.6% of CP were women). No adverse events occurred. MiM participants rated the program highly (average score of 4.5/5). PLWD reported improved quality of life post-MiM (p = <0.01). Altogether, participants reported increased physical activity levels (p = <0.01) and cognitive activity levels (p = <0.01). The virtual MiM program is acceptable, safe, and effective at improving quality of life, cognitive and physical activity levels for PLWD, and cognitive and physical activity levels among CP.

Association between cognitive impairment and motor dysfunction among patients with multiple sclerosis: a cross-sectional study

BACKGROUND

Previous studies have shown that there is a relationship between cognitive impairment (CI) and motor dysfunction (MD) in neurological diseases, such as Alzheimer's and Parkinson's disease. However, there whether CI and MD are associated in patients with multiple sclerosis (MS) is unknown. Here we studied the association between CI and MD in patients with MS and examined if muscle weakness or incoordination, balance impairment, gait abnormalities, and/or increased fall risk are indicators of CI in patients with MS.

METHODS

Seventy patients with MS were included in this cross-sectional study. Cognitive impairment was assessed using the Montreal Cognitive Assessment Scale (MoCA), muscle strength using a hand-held dynamometer, and balance, gait, and fall risk assessment using the Tinetti scale. Motor coordination was assessed using the timed rapid alternating movement test for the upper extremity and the timed alternate heel-to-knee test for the lower extremity.

RESULTS

There was a significant association between CI and motor coordination, balance, gait, and risk of fall (p < 0.005) but not muscle strength. Stepwise multiple linear regression showed that 22.7% of the variance in the MoCA was predicted by the fall risk and incoordination of the upper extremities in the MS population.

CONCLUSIONS

CI is significantly associated with motor incoordination, balance impairment, gait abnormality, and increased fall risk. Furthermore, the risk of fall and upper extremity incoordination appeared to be best indicators of CI in patients with MS.

Reach-to-grasp kinematics and kinetics with and without visual feedback in early-stage Alzheimer’s disease

This study aimed to investigate the effects of early-stage Alzheimer’s disease (AD) on the reach-to-grasp kinematics and kinetics with and without visual supervision of the grasping arm and hand. Seventeen patients who had been diagnosed with early-stage AD and 17 age- and gender-matched, cognitive normal (CN) adults participated in the experiment. A mirror operating system was designed to block the visual feedback of their grasping hand and forearms but to virtually show grasped targets. The target for reach-to-grasp kinematics was a reflective marker installed on a base; and the target for reach-to-grasp kinetics was a custom-made apparatus installed with two six-component force/torque transducers. Kinematics and kinetic parameters were used to quantify the reach-to-grasp performances. Results showed that the early-stage AD remarkably decreased the reaching speed, reduced the grasping accuracy and increased the transportation variability for reach-to-grasp kinematics. For kinetic analysis, early-stage AD extended the preload duration, disturbed the grip and lift forces coordination, and increased the feedforward proportion in the grasping force control. The AD-related changes in the reach-to-grasp kinematic and kinetic parameters depended on visual feedback and were associated with nervous system function according to correlation analyses with the neuropsychological testing. These results suggest that the abnormal kinematic and kinetic characteristics may correlate with the neuropsychological status of early-stage AD, and that the reach-to-grasp kinematic and kinetic maneuver could potentially be used as a novel tool for non-invasive screening or evaluation of early-stage AD.

Correlation between changes in Timed Up and Go performance and cognition in older people with mild cognitive impairment: A longitudinal study

BACKGROUND

Compare changes in performance on subtasks of the Timed Up and Go test over 32 months in older adults with and without mild cognitive impairment; analyze the correlation between frontal cognitive functions at baseline and changes in Timed Up and Go subtasks over time.

METHODS

A longitudinal study was conducted involving 31 older adults (15 with and 16 without cognitive impairment). Functional mobility was assessed at both evaluations using an adapted version of the Timed Up and Go test and the Qualisys motion system. The test was divided into five subtasks: sit-to-stand, walking forward, turn-to-walk, walking back and turn-to-sit. Cognition was assessed at baseline using the Frontal Assessment Battery and the Clock Drawing Test.

FINDINGS

Significant differences in changes in the sit-to-stand subtask over time were found between groups. The difference in the time required to conclude this subtask was greater in the older adults with cognitive impairment. However, the difference in kinematic variables (peak trunk speed and range of motion) was greater in the group without cognitive impairment. Strong and moderate correlations were found between frontal cognitive functions and changes in Timed Up and Go subtasks, especially those involving transitions (sit-to-stand, turn-to-walk and turn-to-sit) in both groups.

INTERPRETATION

Motor intervention protocols should incorporate the sit-to-stand subtask in older adults with mild cognitive impairment. Moreover, changes in more complex subtasks seem to be related to frontal cognitive performance at baseline. Therefore, treatments that combine motor and cognitive functions should be administered to older adults regardless of cognitive impairment.

Neuropsychology of posteromedial parietal cortex and conversion factors from Mild Cognitive Impairment to Alzheimer's disease: systematic search and state-of-the-art review

In the present review, we discuss the rationale and the clinical implications of assessing visuospatial working memory (VSWM), awareness of memory deficits, and visuomotor control in patients with mild cognitive impairment (MCI). These three domains are related to neural activity in the posteromedial parietal cortex (PMC) whose hypoactivation seems to be a significant predictor of conversion from MCI to Alzheimer’s disease (AD) as indicated by recent neuroimaging evidence. A systematic literature search was performed up to May 2021. Forty-eight studies were included: 42 studies provided analytical cross-sectional data and 6 studies longitudinal data on conversion rates. Overall, these studies showed that patients with MCI performed worse than healthy controls in tasks assessing VSWM, awareness of memory deficits, and visuomotor control; in some cases, MCI patients’ performance was comparable to that of patients with overt dementia. Deficits in VSWM and metamemory appear to be significant predictors of conversion. No study explored the relationship between visuomotor control and conversion. Nevertheless, it has been speculated that the assessment of visuomotor abilities in subjects at high AD risk might be useful to discriminate patients who are likely to convert from those who are not. Being able to indirectly estimate PMC functioning through quick and easy neuropsychological tasks in outpatient settings may improve diagnostic and prognostic accuracy, and therefore, the quality of the MCI patient’s management.

Anticipatory and Reactive Grip Force Control in Patients with Alzheimer's Disease: A Pilot Study

BACKGROUND

Alzheimer's disease (AD) affects several cognitive functions and causes altered motor function. Fine motor deficits during object manipulation are evident in other neurological conditions, but have not been assessed in dementia patients yet.

OBJECTIVE

Investigate reactive and anticipatory grip force control in response to unexpected and expected load force perturbation in AD.

METHODS

Reactive and anticipatory grip force was investigated using a grip-device with force sensors. In this pilot study, fifteen AD patients and fourteen healthy controls performed a catching task. They held the device with one hand while a sandbag was dropped into an attached receptacle either by the experimenter or by the participant.

RESULTS

In contrast to studies of other neurological conditions, the majority of AD patients exerted lower static grip force levels than controls. Interestingly, patients who were slow in the Luria's three-step test produced normal grip forces. The timing and magnitude of reactive grip force control were largely preserved in patients. In contrast, timing and extent of anticipatory grip forces were impaired in patients, although anticipatory control was generally preserved. These deficits were correlated with decreasing Mini-Mental State Examination scores. Apraxia scores, assessed by pantomime of tool-use, did not correlate with performance in the catching task.

CONCLUSION

We interpreted the decreased grip force in AD in the context of loss of strength and lethargy, typical for patients with AD. The lower static grip force during object manipulation may emerge as a potential biomarker for early stages of AD, but more studies with larger sample sizes are necessary.

Clinical assessment of gait and functional mobility in Italian healthy and cognitively impaired older persons using wearable inertial sensors

AIM

The main purpose of the present study was to verify the feasibility of wearable inertial sensors (IMUs) in a clinical setting to screen gait and functional mobility in Italian older persons. In particular, we intended to verify the capability of IMUs to discriminate individuals with and without cognitive impairments and assess the existence of significant correlations between mobility parameters extracted by processing trunk accelerations and cognitive status.

METHODS

This is a cross-sectional study performed on 213 adults aged over 65 years (mean age 77.0 ± 5.4; 62% female) who underwent cognitive assessment (through Addenbrooke's Cognitive Examination Revised, ACE-R) instrumental gait analysis and the Timed Up and Go (TUG) test carried out using a wearable IMU located in the lower back.

RESULTS

Individuals with cognitive impairments exhibit a peculiar gait pattern, characterized by significant reduction of speed (- 34% vs. healthy individuals), stride length (- 28%), cadence (- 9%), and increase in double support duration (+ 11%). Slight, but significant changes in stance and swing phase duration were also detected. Poorer performances in presence of cognitive impairment were observed in terms of functional mobility as overall and sub-phase TUG times resulted significantly higher with respect to healthy individuals (overall time, + 38%, sub-phases times ranging from + 22 to + 34%), although with some difference associated with age. The severity of mobility alterations was found moderately to strongly correlated with the ACE-R score (Spearman's rho = 0.58 vs. gait speed, 0.54 vs. stride length, 0.66 vs. overall TUG time).

CONCLUSION

The findings obtained in the present study suggest that wearable IMUs appear to be an effective solution for the clinical assessment of mobility parameters of older persons screened for cognitive impairments within a clinical setting. They may represent a useful tool for the clinician in verifying the effectiveness of interventions to alleviate the impact of mobility limitations on daily life in cognitively impaired individuals.

Clinicopathological Staging of Dynamics of Neurodegeneration and Neuronal Loss in Alzheimer Disease

Clinical and neuropathological staging of Alzheimer disease (AD) neurodegeneration and neuronal loss dynamics is the baseline for identification of treatment targets and timing. The aim of this study of 14 brain regions in 25 subjects diagnosed with AD and 13 age-matched control subjects was to establish the pattern of neurodegeneration, and the severity and rate of neuronal loss in mild cognitive impairment/mild AD (Functional Assessment Staging [FAST] test 3-4), moderate to moderately severe AD (FAST 5-6), and severe AD (FAST 7). The study revealed (1) the most severe neuronal loss in FAST 3-4; (2) the highest rate of neuronal loss in FAST 5-6, to the "critical" point limiting further increase in neuronal loss; (3) progression of neurofibrillary degeneration, but decline of neuronal loss to a floor level in FAST 7; and (4) structure-specific rate of neuronal loss caused by neurofibrillary degeneration and a large pool of neuronal loss caused by other mechanisms. This study defines a range and speed of progression of AD pathology and functional decline that might potentially be prevented by the arrest of neuronal loss, both related and unrelated to neurofibrillary degeneration, during the 9-year duration of mild cognitive impairment/mild AD.

A Study of Changes of Physical Functions According to Changes in Cognitive Functions in Community-Dwelling Elderly People Who Participated in an Exercise Program

Although it is known that physical function differs depending on the state of cognitive function, there are no studies that consider changes in cognitive functions when evaluating physical functions of participants before and after an exercise program. In this study, it was observed changes in cognitive function and physical functions of elderly people who participated in a community-based exercise program for 6 months, and examined changes in physical functions that took into account changes in cognitive functions. Forty-nine participants, whose cognitive and physical functions were both measured before and after the exercise program, were included in the analysis. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used to assess participants' cognitive function and to determine whether they had mild cognitive impairment (MCI). To assess physical functions, a battery of physical tests was completed. Participants were classified into four groups (before/after; non-MCI/non-MCI, MCI/MCI, non-MCI/MCI, and MCI/non-MCI) according to the changes in cognitive functions after six months. There was no significant difference in the physical functions of the four groups before the start of the program. When changes in physical functions were examined in each group, some changes in physical functions were observed in the groups other than the non-MCI/MCI group. However, there was no significant difference in the physical functions between the four groups after the program. It was suggested that changes in physical functions of elderly people who participated in a community-based exercise program over a 6-month period were not different due to changes in cognitive functions.

Translational Modeling of Psychomotor Function in Normal and AD-Pathological Aging With Special Concerns on the Effects of Social Isolation

One year after the start of the COVID-19 pandemic, its secondary impacts can be globally observed. Some of them result from physical distancing and severe social contact restrictions by policies still imposed to stop the fast spread of new variants of this infectious disease. People with Alzheimer's disease (AD) and other dementias can also be significantly affected by the reduction of their activity programs, the loss of partners, and social isolation. Searching for the closest translational scenario, the increased mortality rates in male 3xTg-AD mice modeling advanced stages of the disease can provide a scenario of “naturalistic isolation.” Our most recent work has shown its impact worsening AD-cognitive and emotional profiles, AD-brain asymmetry, and eliciting hyperactivity and bizarre behaviors. Here, we further investigated the psychomotor function through six different psychomotor analysis in a set of 13-month-old 3xTg-AD mice and their non-transgenic counterparts with normal aging. The subgroup of male 3xTg-AD mice that lost their partners lived alone for the last 2–3 months after 10 months of social life. AD's functional limitations were shown as increased physical frailty phenotype, poor or deficient psychomotor performance, including bizarre behavior, in variables involving information processing and decision-making (exploratory activity and spontaneous gait), that worsened with isolation. Paradoxical muscular strength and better motor performance (endurance and learning) was shown in variables related to physical work and found enhanced by isolation, in agreement with the hyperactivity and the appearance of bizarre behaviors previously reported. Despite the isolation, a delayed appearance of motor deficits related to physical resistance and tolerance to exercise was found in the 3xTg-AD mice, probably because of the interplay of hyperactivity and mortality/survivor bias. The translation of these results to the clinical setting offers a guide to generate flexible and personalized rehabilitation strategies adaptable to the restrictions of the COVID-19 pandemic.

AGE–GENDER DIFFERENCE IN THE PERCEPTION AND MUSCLE RESPONSE THRESHOLDS OF SUPPORT SURFACE ROTATION

Proprioception while standing is important for the balance control, but the proprioception has not been investigated in the unconstrained standing conditions. The purpose of this study was to investigate the effects of age and gender on the thresholds of perception and muscle response in response to the support surface rotation. The experiment was designed so that the thresholds depend mainly on the proprioception, i.e., quasistatic condition (0.2∘/s rotation of the platform) with eyes closed. Fifty-two healthy subjects (half young and half elderly) participated in this study. A platform was developed which can be rotated in four directions. Perception threshold angle was registered from subjects’ pressing a button. Muscle response threshold angle was determined as the earlier onset of EMG in lower limb muscles. Two standing conditions (feet together and natural stance) were tested. Repeated-measures ANOVA showed that both thresholds increased with age. Post hoc tests revealed (1) that the perception threshold was greater for women than men in the elderly and (2) both thresholds of the elderly were greater for the feet-together stance than natural stance. Inferior perception sensitivity of platform rotation in elderly women may be associated with inferior performance in cortical postural control and greater fall ratio compared to elderly men, which suggests the need of proprioception trainings.

Short and medium-term effects of a multicomponent physical exercise program with a Mediterranean diet on bone mineral density, gait, balance, and fall risk for patients with Alzheimer disease: Randomized controlled clinical trial study protocol

INTRODUCTION

Reduced bone mineral density and increased risk of falls are related with Alzheimer disease, and these increase likelihood of bone osteoporotic fractures causing serious complications such as disability, fear of falling, loss autonomy, decreased quality of life, and anticipated mortality in elderly patients. Gait and balance disturb are 2 factors to favor falls in elderly, and in patients with cognitive impairment, the risk of falls increases to double. Exercise and Mediterranean diet produce beneficial effects for aging, cognitive decline, and are widely recommended to reduce the effects of osteoporosis, fall risk, and related fragility fractures. The primary objective of this study is to evaluate the short and medium-term effects during 6 months, of a multicomponent physical exercise program with a Mediterranean diet on bone mineral density, fall risk, balance, and gait by a controlled clinical trial in patients with Alzheimer disease.

METHODS

The study is a 6-month, randomized controlled parallel-group, single-blinded clinical trial. Institutionalized patients with Alzheimer disease will be included. The intervention group will perform a multicomponent physical exercise program in reduced groups, with a frequency of 3 sessions per week, associated with a Mediterranean diet. This program includes strength, balance, and aerobic resistance exercises, and in the main part of the session, also ludic exercises to improve agility, coordination, and balance. The control group will receive usual care. The outcomes to assess are the change of physical functions, such as gait and balance, and the change of bone mineral density by calcaneal quantitative ultrasound, during the study follow-up at 1, 3, and 6 months. This clinical trial will generate more and new evidence on the effects of a multicomponent physical exercise program and Mediterranean diet in patients with Alzheimer disease on risk of falls and osteoporotic fractures, the relation of these with bone mineral density, gait and balance, and the correlations between them.

ETHICS AND DISSEMINATION

This study protocol has been approved by the Ethics Committee of the University of Salamanca. The results will be published in peer-reviewed journals and disseminated in national and international conferences, to the participants and their families, and the general public through the associations of people with AD.

TRIAL REGISTRATION ID

ClínicalTrials.gov ID: NCT04439097.

Individual and combined effects of a cognitive task, light finger touch, and vision on standing balance in older adults with mild cognitive impairment

BACKGROUND

Postural instability and balance dysfunction have been identified in older adults with mild cognitive impairment (MCI). Performing a secondary task while standing can additionally jeopardize their balance.

AIMS

The purpose of the exploratory study was to investigate the individual and combined effects of a cognitive task, light finger touch and vision on postural sway in older adults with MCI as compared to healthy older adults.

METHODS

Five individuals with MCI and ten age-matched control subjects stood on the force platform with and without the performance of a cognitive task (counting backward from a randomly chosen three-digit number), with and without light finger touch contact applied to an external stable structure, and with eyes open or closed. The center of pressure (COP) excursion, range, velocity in antero-posterior and medial-lateral directions and sway area were calculated.

RESULTS

Participants demonstrated significantly larger postural sway when vision was not available (p < 0.05), smaller postural sway when using a finger touch contact (p < 0.05) and increased postural sway during the performance of the cognitive task (p < 0.05). When finger touch and a cognitive task were performed simultaneously, body sway decreased as compared to just standing in healthy older adults but not in individuals with MCI (p < 0.05).

CONCLUSIONS

The results help to better understand the individual and combined effects of vision, light touch and a cognitive task in postural control of individuals with MCI. The study outcome also provides a basis for future studies of balance control in patients with cognitive impairments.

Analysis of Functional and Cognitive Impairment in Institutionalized Individuals with Movement Disorders

BACKGROUND

Many neurological disorders lead to institutionalization and can be accompanied in their advanced stages by functional impairment, and progressive loss of mobility, and cognitive alterations.

OBJECTIVE

We analyzed the relationship between functional impairment and cognitive performance and its related subdomains in individuals with Parkinson's disease, Alzheimer's disease accompanied by motor dysfunction, and with other neurological disorders characterized by both motor and cognitive problems.

METHODS

All participants lived in nursing homes (Valencia, Spain) and underwent cognitive evaluation with the Mini-Mental State Examination; functional assessment of independence in activities of daily living using the Barthel score and Katz index; and assessment of mobility with the elderly mobility scale.

RESULTS

The mean age of the subjects was 82.8 ± 0.6 years, 47% of the sample included individuals with Parkinson's disease, and 48 % of the sample presented severe cognitive impairment. Direct significant relationships were found between the level of cognitive impairment and functional capacity (p < 0.01) and mobility (p < 0.05). Among the different domains, memory impairment was not associated with altered activities of daily living or mobility. The functional impairment and the risk of severe cognitive impairment were significantly (p<0.05) higher in female compared to male patients. Among comorbidities, overweight/obesity and diabetes were significantly (p < 0.05) associated with poor cognitive performance in those individuals with mild/moderate cognitive impairment.

CONCLUSION

In institutionalized individuals with movement disorders there is an association between functional and cognitive impairment. Reduction of over-weight and proper control of diabetes may represent novel targets for improving cognitive function at such early stages.

Role of a single session of ball throwing exercise on postural control in older adults with mild cognitive impairment

PURPOSE

The purpose of the study was to investigate the role of training in improvement of balance control in older adults with mild cognitive impairment.

METHODS

Older adults (mean age 78) with mild cognitive impairment (MCI) and cognitively intact older adults (mean age 72) were exposed to self-initiated perturbations while performing bilateral shoulder flexion task before and after a single training session consisting of throwing a medicine ball. EMG activity of six trunk and lower limb muscles was recorded. Muscle onsets, integrals of EMG, and muscle co-contraction (C) and reciprocal (R) activation indices were calculated and analyzed during the anticipatory and compensatory phases of postural control.

RESULTS

Anticipatory postural adjustments (APAs) were observed in both groups.  Individuals with MCI, as compared to controls, had higher level of co-contraction of muscles. The training resulted in enhancement of the generation of APAs in individuals with MCI seen as earlier onset of leg and trunk muscle activity prior to the bilateral arm flexion task. While smaller co-contraction of muscles post-training was seen in both the groups, the effect of a single training session was significant in control subjects only.

CONCLUSIONS

The outcome of the exploratory study suggests that perturbation-based training could be used to improve balance control in older adults with and without mild cognitive impairment.

Purkinje Cells Pathology in Alzheimer's Disease

Alzheimer's disease (AD) is one of the main causes of dementia in senium and presenium. It is clinically characterized by memory impairment, deterioration of intellectual faculties, and loss of professional skills. The cerebellum is a critical part in the distributed neural circuits participating not only in motor function but also in autonomic, limbic, and cognitive behaviors. In present study, we aim to investigate the morphological changes in the Purkinje cells in different cerebellar regions in AD and to correlate them with the underlying AD pathology. Purkinje cells exhibit significant morphometric alterations in AD and prominently in the anterior lobe which is related to higher cognitive functions. The present study gives new insights into the cerebellar pathology in AD and confirms that Purkinje cells pathology is a key finding in AD brains and that AD is characterized by regional-specific atrophy picked in the anterior cerebellar lobe.

Relationship between mobility and cognitive impairment in patients with Alzheimer's disease

OBJECTIVE

Alzheimer's disease (AD) is usually accompanied by impairments to mobility, performance of the basic activities of daily life (ADL), and progressive cognitive decline. We analyzed the relationship between cognitive performance and related cognitive subdomains and mobility.

PATIENTS AND METHODS

All AD patients of the recruited individuals were living in nursing homes; they underwent a blood analysis, cognitive examination by using the Mini-Mental State Examination, functional evaluation of independence in the ADLs with Barthel score and Katz index, and mobility assessment with the elderly mobility scale.

RESULTS

The mean sample age was 84 years and majority were women; more than 60% of the participants had severe cognitive impairment. Statistically significant relationships were found between the severity of cognitive impairment and functional capacity (p <  0.01) and their degree of mobility (p <  0.05). Among the different domains, memory impairment was not associated with impaired mobility or ability to perform the ADLs. Women had lower scores in the ADL and mobility assessments (p <  0.05) and an increased ratio of severe cognitive impairment (OR = 3.03 95% CI: [1.30, -7.05]) compared to men. Being overweight or obese and high blood levels of HDL cholesterol were directly (p <  0.05) and inversely (p <  0.01) associated with poor cognitive performance in individuals with mild to moderate cognitive dysfunction, respectively.

CONCLUSIONS

This study shows that better functional capacity and mobility are generally, but not exclusively, correlated with better cognitive function, depending on the severity of cognitive impairment. In contrast, lipid profile alterations might play a role in cognitive deficits in individuals with mild to moderate cognitive impairment who are overweight. Further longitudinal studies will be required to explore this possibility.

Two Year Outcomes, Cognitive and Behavioral Markers of Decline in Healthy, Cognitively Normal Older Persons with Global Deterioration Scale Stage 2 (Subjective Cognitive Decline with Impairment)

BACKGROUND

Little is known with respect to behavioral markers of subjective cognitive decline (SCD), a condition initially described in association with Global Deterioration Scale (GDS) stage 2.

OBJECTIVE

Two-year interval behavioral markers were investigated herein.

METHODS

Subjects from a published 7-year outcome study of GDS stage 2 subjects were selected. This study had demonstrated a hazard ratio of 4.5 for progression of GDS stage 2, in comparison with GDS stage 1 (no subjective or objective cognitive decline) subjects, after controlling for demographic and temporal variables. Because GDS 2 subjects have previously demonstrated impairment in comparison with healthy persons free of complaints, we herein suggest the terminology "SCD(I)" for these persons. 98 SCD(I) persons, 63 women and 35 men, mean baseline age, 67.12±8.75 years, with a mean educational background of 15.55±2.60 years, and mean baseline MMSE scores of 28.9±1.24 were followed for 2.13±0.30 years.

RESULTS

Observed annual decline on the GDS was 6.701% per annum, very close to a 1986 published estimate. At follow up, the MMSE, and 7 of 8 psychometric tests did not decline significantly. Of 21 Hamilton Depression Scale items, 2 improved and the remainder were unchanged. Anxieties declined from multiple perspectives. The Brief Cognitive Rating Scale (BCRS) declined significantly (p < 0.001), with component declines in Remote memory (p < 0.01), and Functioning/self-care (p = 0.01).

CONCLUSION

SCD(I) persons decline at an annual rate of approximately 6.7% /year from several recent studies. The BCRS assessments and the Digit Symbol Substitution Test can be sensitive measures for future studies of progression mitigation.

Increased Prevalence of Vestibular Loss in Mild Cognitive Impairment and Alzheimer's Disease

BACKGROUND/AIMS

Recent evidence has shown that Alzheimer's Disease (AD) patients have reduced vestibular function relative to healthy controls. In this study, we evaluated whether patients with Mild Cognitive Impairment (MCI) also have reduced vestibular function relative to controls, and compared the level of vestibular impairment between MCI and AD patients.

METHODS

Vestibular physiologic function was assessed in 77 patients (26 MCI, 51 AD) and 295 matched controls using 3 clinical vestibular tests. The association between vestibular loss and cognitive impairment was evaluated using conditional logistic regression models.

RESULTS

Individuals with vestibular impairment had a 3 to 4-fold increased odds of being in the MCI vs. control group (p-values < 0.05). MCI patients had a level of vestibular impairment that was intermediate between controls and AD.

CONCLUSION

These findings suggest a dose-response relationship between vestibular loss and cognitive status, and support the hypothesis that vestibular loss contributes to cognitive decline.

The Impact of Paratonia on Fine and Gross Motor Function in Older Adults With Mild and Moderate Dementia

BACKGROUND

Dementia is associated with impairment in gait, balance, and fine motor function. Paratonia, a form of hypertonia, is often present in severe dementia. However, little is known about muscle tone in early dementia, and the eventual relation between muscle tone abnormalities and changes in fine and gross motor function.

METHODS

Three groups of participants were included in the study: healthy controls (n=60), participants with mild dementia (MiD) (n=31), and participants with moderate dementia (n=31). Measurements of fine motricity (Purdue pegboard test), balance and gait (Dynaport Hybrid), the presence of paratonia (PAI), and muscle tone measurements (MyotonPRO) were performed.

RESULTS

Paratonia was present in 42% of participants with MiD and in 58% of participants with moderate dementia. Participants with paratonia had lower Purdue Pegboard scores (P<0.001), lower balance coordination in semitandem stance (P<0.001), lower walking speed at a fast pace (P=0.001), and lower step regularity at normal (P=0.025) and fast (P<0.001) pace.

CONCLUSIONS

Paratonia is already present in participants with MiD and is associated with a decline in both fine and gross motor performance. Early detection of paratonia might be helpful to detect persons at higher risk of motor deterioration and falls.

Manual Dexterity and Aging: A Pilot Study Disentangling Sensorimotor From Cognitive Decline

Manual dexterity measures can be useful for early detection of age-related functional decline and for prediction of cognitive decline. However, what aspects of sensorimotor function to assess remains unclear. Manual dexterity markers should be able to separate impairments related to cognitive decline from those related to healthy aging. In this pilot study, we aimed to compare manual dexterity components in patients diagnosed with cognitive decline (mean age: 84 years, N = 11) and in age comparable cognitively intact elderly subjects (mean age: 78 years, N = 11). In order to separate impairments due to healthy aging from deficits due to cognitive decline we also included two groups of healthy young adults (mean age: 26 years, N = 10) and middle-aged adults (mean age: 41 years, N = 8). A comprehensive quantitative evaluation of manual dexterity was performed using three tasks: (i) visuomotor force tracking, (ii) isochronous single finger tapping with auditory cues, and (iii) visuomotor multi-finger tapping. Results showed a highly significant increase in force tracking error with increasing age. Subjects with cognitive decline had increased finger tapping variability and reduced ability to select the correct tapping fingers in the multi-finger tapping task compared to cognitively intact elderly subjects. Cognitively intact elderly subjects and those with cognitive decline had prolonged force release and reduced independence of finger movements compared to young adults and middle-aged adults. The findings suggest two different patterns of impaired manual dexterity: one related to cognitive decline and another related to healthy aging. Manual dexterity tasks requiring updating of performance, in accordance with (temporal or spatial) task rules maintained in short-term memory, are particularly affected in cognitive decline. Conversely, tasks requiring online matching of motor output to sensory cues were affected by age, not by cognitive status. Remarkably, no motor impairments were detected in patients with cognitive decline using clinical scales of hand function. The findings may have consequences for the development of manual dexterity markers of cognitive decline.

Which strength and balance activities are safe and efficacious for individuals with specific challenges (osteoporosis, vertebral fractures, frailty, dementia)?: A Narrative review

Physical activity guidelines advocate the inclusion of strength and balance activities, twice a week, for adults and older adults, but with caveat that in some individuals there will be certain movements and activities that could lead to adverse events. This scoping review summarizes the evidence about how safe and efficacious these activities are in older adults with specific challenges that might make them more prone to injury (e.g. having recently fractured or at risk of fracture (osteoporosis) or those who are frail or who have cognitive impairment). The review identified that for prevention of falls in people with a falls history and/or frailer older adults, structured exercise programmes that incorporate progressive resistance training (PRT) with increasing balance challenges over time are safe and effective if performed regularly, with supervision and support, over at least 6 months. Some minor adverse effects mainly transient musculoskeletal pain) have been reported. For those with a higher risk of falls and fractures (very poor balance, vertebral fractures), supervised structured exercise programmes are most appropriate. People with diagnosed osteoporosis should be as active as possible and only avoid activities with a high risk of falls if they are naïve to those activities. For those in transition to frailty who have poor strength and balance, exercises that are known to help maintain strength and balance (such as Tai Chi) are effective in preventing a decline in falls risk. For the very frail older adult, supervised structured exercise that has PRT, balance training and some endurance work, supervised and progressed by a trained person are advocated.

Paratonia in Flemish Nursing Homes: Current State of Practice

BACKGROUND

Paratonia is a major underlying motor problem impeding functionality and locomotion in dementia. Despite its undeniable impact on patient's quality of life and daily care, there is a lack of evidence-based therapy on patients with this condition.

METHODS

We surveyed physiotherapists working in nursing homes in Flanders (Belgium) concerning the use and perceived effect of therapeutic strategies and positioning methods/aids.

RESULTS

Positioning and soft passive mobilization were the most applied and positively appraised therapeutic interventions. Highest ratings for positioning were found for C-shaped positioning cushions and multi-position wheelchair. According to the respondents, key points for paratonia approach were relaxation, positioning, active movement stimulation, and-to some extent-passive mobilization. Indispensable for any success however is multidisciplinary cooperation.

CONCLUSION

These findings might provide an inspirational path for research to verify possible (evidence based) beneficial treatments that could be applied to improve current and future treatment of patients with paratonia.

Home-Based Exercise Program Improves Balance and Fear of Falling in Community-Dwelling Older Adults with Mild Alzheimer's Disease: A Pilot Study

BACKGROUND/OBJECTIVE

Balance problems are common in older adults with Alzheimer's disease (AD). The objective was to study the effects of a Wii-Fit interactive video-game-led physical exercise program to a walking program on measures of balance in older adults with mild AD.

METHODS

A prospective randomized controlled parallel-group trial (Wii-Fit versus walking) was conducted in thirty community-dwelling older adults (73±6.2 years) with mild AD. Home-based exercises were performed under caregiver supervision for 8 weeks. Primary (Berg Balance Scale, BBS) and secondary outcomes (fear of falls and quality of life) were measured at baseline, 8 weeks (end of intervention), and 16 weeks (8-weeks post-intervention).

RESULTS

At 8 weeks, there was a significantly greater improvement (average inter-group difference [95% CI]) in the Wii-Fit group compared to the walking group in BBS (4.8 [3.3-6.2], p < 0.001), after adjusting for baseline. This improvement was sustained at 16 weeks (3.5 [2.0-5.0], p < 0.001). Analyses of the secondary outcome measures indicated that there was a significantly greater improvement in the Wii-Fit group compared to walking group in Activity-specific Balance Confidence scale (6.5 [3.6-9.4], p < 0.001) and Falls Efficacy Scale (-4.8 [-7.6 to -2.0], p = 0.002) at 8 weeks. However, this effect was not sustained at 16 weeks. Quality of life improved in both groups at 8 weeks; however, there were no inter-group differences (p = 0.445).

CONCLUSION

Home-based, caregiver-supervised Wii-Fit exercises improve balance and may reduce fear of falling in community-dwelling older adults with mild AD.

Quantitative assessment of finger tapping characteristics in mild cognitive impairment, Alzheimer's disease, and Parkinson's disease

BACKGROUND

Fine motor impairments are common in neurodegenerative disorders, yet standardized, quantitative measurements of motor abilities are uncommonly used in neurological practice. Thus, understanding and comparing fine motor abilities across disorders have been limited.

OBJECTIVES

The current study compared differences in finger tapping, inter-tap interval, and variability in Alzheimer's disease (AD), Parkinson's disease (PD), mild cognitive impairment (MCI), and healthy older adults (HOA).

METHODS

Finger tapping was measured using a highly sensitive light-diode finger tapper. Total number of finger taps, inter-tap interval, and intra-individual variability (IIV) of finger tapping was measured and compared in AD (n = 131), PD (n = 63), MCI (n = 46), and HOA (n = 62), controlling for age and sex.

RESULTS

All patient groups had fine motor impairments relative to HOA. AD and MCI groups produced fewer taps with longer inter-tap interval and higher IIV compared to HOA. The PD group, however, produced more taps with shorter inter-tap interval and higher IIV compared to HOA.

CONCLUSIONS

Disease-specific changes in fine motor function occur in the most common neurodegenerative diseases. The findings suggest that alterations in finger tapping patterns are common in AD, MCI, and PD. In addition, the present results underscore the importance of motor dysfunction even in neurodegenerative disorders without primary motor symptoms.

Clinical Aspects of Foot Health in Individuals with Alzheimer's Disease

Alzheimer's disease (AD) shows a marked presence of physiologic changes and the start or aggravation of underlying diseases such as physical frailty in diverse anatomical regions. It is believed to have a particularly harmful effect on the health of the foot. We examined the foot health status in older persons with AD, with a specific focus on the extent to which people with AD may be using inadequate footwear in old age. Seventy-three community-dwelling people with probable, mild to moderate AD aged 65-95 years were recruited from a center of excellence for AD. A single trained physician evaluated health status and foot conditions. Current shoe and foot length and width measurements were taken using a calibrated Brannock device. The results indicate that sixty-five participants (89.04%) suffered from feet problems. Also, only twenty-two subjects (30.14%) used the correct shoes in width and size related with the morphology of their feet. Fifty-one participants (69.86%) were using incorrect shoes in length or width. The present study revealed that peoples with AD had a high presence of foot health problems. Also, the use of inappropriate shoes revealed measurable differences of association between shoe size and the morphology of the foot.

Dementia

Dementia is a syndrome seen most commonly in older people and characterized by a decline in cognitive performance which impacts on the person's ability to function. There are approximately 47 million people worldwide with dementia and there are 10 million new cases every year. It is a major cause of disability and dependence and impacts on the physical, psychologic, and social well-being of families and carers. Alzheimer's disease is the most common form of dementia. Gait and balance impairments are common in people with dementia and contribute to the significantly elevated risk of falls. Older people with dementia are at increased risk of injury, institutionalization, hospitalization, morbidity, and death after a fall. There is preliminary evidence, predominantly from relatively small studies, that falls and disability can be prevented in this population. However, more good-quality research is needed, both to provide some certainty around the existing evidence base as well as to explore alternate approaches to prevention, including combined cognitive-motor training and cognitive pharmacotherapy.

Physical exercise improves strength, balance, mobility, and endurance in people with cognitive impairment and dementia: a systematic review

QUESTION

Does physical exercise training improve physical function and quality of life in people with cognitive impairment and dementia? Which training protocols improve physical function and quality of life? How do cognitive impairment and other patient characteristics influence the outcomes of exercise training?

DESIGN

Systematic review with meta-analysis of randomised trials.

PARTICIPANTS

People with mild cognitive impairment or dementia as the primary diagnosis.

INTERVENTION

Physical exercise.

OUTCOME MEASURES

Strength, flexibility, gait, balance, mobility, walking endurance, dual-task ability, activities of daily living, quality of life, and falls.

RESULTS

Forty-three clinical trials (n=3988) were included. According to the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) system, the meta-analyses revealed strong evidence in support of using supervised exercise training to improve the results of 30-second sit-to-stand test (MD 2.1 repetitions, 95% CI 0.3 to 3.9), step length (MD 5cm, 95% CI 2 to 8), Berg Balance Scale (MD 3.6 points, 95% CI 0.3 to 7.0), functional reach (3.9cm, 95% CI 2.2 to 5.5), Timed Up and Go test (-1second, 95% CI -2 to 0), walking speed (0.13m/s, 95% CI 0.03 to 0.24), and 6-minute walk test (50m, 95% CI 18 to 81) in individuals with mild cognitive impairment or dementia. Weak evidence supported the use of exercise in improving flexibility and Barthel Index performance. Weak evidence suggested that non-specific exercise did not improve dual-tasking ability or activity level. Strong evidence indicated that exercise did not improve quality of life in this population. The effect of exercise on falls remained inconclusive. Poorer physical function was a determinant of better response to exercise training, but cognitive performance did not have an impact.

CONCLUSION

People with various levels of cognitive impairment can benefit from supervised multi-modal exercise for about 60minutes a day, 2 to 3days a week to improve physical function. [Lam FMH , Huang MZ, Liao LR, Chung RCK, Kwok TCY, Pang MYC (2018) Physical exercise improves strength, balance, mobility, and endurance in people with cognitive impairment and dementia: a systematic review. Journal of Physiotherapy 64: 4-15].

Quantitative Balance and Gait Measurement in Patients with Frontotemporal Dementia and Alzheimer Diseases: A Pilot Study

INTRODUCTION

Alzhiemers disease and Frontotemporal dementia are common neurodegenerative dementias with a wide prevalence. Falls are a common cause of morbidity in these patients. Identifying subclinical involvement of these parameters might serve as a tool in differential analysis of these distinct parameters involved in these conditions and also help in planning preventive strategies to prevent falls.

PATIENTS AND METHODS

Eight patients in age and gender matched patients in each group were compared with normal controls. Standardizes methods of gait and balance aseesment were done in all persons.

RESULTS

Results revealed subclinical involvement of gait and balancesin all groups specially during divided attention. The parameters were significantly more affected in patients. Patients with AD and FTD had involement of over all ambulation index balance more affected in AD patients FTD patients showed step cycle, stride length abnormalities.

DISCUSSION

There is balance and gait involvement in normal ageing as well as patients with AD and FTD. The pattern of involvement in AD correlates with WHERE pathway involvement and FTD with frontal subcortical circuits involvement.

CONCLUSION

Identification the differential patterns of involvement in subclinical stage might help to differentiate normal ageing and the different types of cortical dementias. This could serve as an additional biomarker and also assist in initiating appropriate training methods to prevent future falls.

Comprehensive, Individualized, Person-Centered Management of Community-Residing Persons with Moderate-to-Severe Alzheimer Disease: A Randomized Controlled Trial

BACKGROUND/AIMS

The aim was to examine added benefits of a Comprehensive, Individualized, Person-Centered Management (CI-PCM) program to memantine treatment.

METHODS

This was a 28-week, clinician-blinded, randomized, controlled, parallel-group study, with a similar study population, similar eligibility criteria, and a similar design to the memantine pivotal trial of Reisberg et al. [N Engl J Med 2003;348:1333-1341]. Twenty eligible community-residing Alzheimer disease (AD) subject-caregiver dyads were randomized to the CI-PCM program (n = 10) or to usual community care (n = 10). Primary outcomes were the New York University Clinician's Interview-Based Impression of Change Plus Caregiver Input (NYU-CIBIC-Plus), assessed by one clinician set, and an activities of daily living inventory, assessed by a separate clinician set at baseline and at weeks 4, 12, and 28.

RESULTS

Primary outcomes showed significant benefits of the CI-PCM program at all post-baseline evaluations. Improvement on the NYU-CIBIC-Plus in the management group at 28 weeks was 2.9 points over the comparator group. The memantine 2003 trial showed an improvement of 0.3 points on this global measure in memantine-treated versus placebo-randomized subjects at 28 weeks. Hence, globally, the management program intervention benefits were 967% greater than memantine treatment alone.

CONCLUSION

These results are approximately 10 times those usually observed with both nonpharmacological and pharmacological treatments and indicate substantial benefits with the management program for advanced AD persons.

Ambulatory Gait Behavior in Patients With Dementia: A Comparison With Parkinson's Disease

Accelerometry-based gait analysis is a promising approach in obtaining insightful information on the gait characteristics of patients with neurological disorders such as dementia and Parkinson's disease (PD). In order to improve its practical use outside the laboratory or hospital, it is required to design new metrics capable of quantifying ambulatory gait and their extraction procedures from long-term acceleration data. This paper presents a gait analysis method developed for such a purpose. Our system is based on a single trunk-mounted accelerometer and analytical algorithm for the assessment of gait behavior that may be context dependent. The algorithm consists of the detection of gait peaks from acceleration data and the analysis of multimodal patterns in the relationship between gait cycle and vertical gait acceleration. A set of six new measures can be obtained by applying the algorithm to a 24-h motion signal. To examine the performance and utility of our method, we recorded acceleration data from 13 healthy, 26 PD, and 26 mild cognitive impairment or dementia subjects. Each patient group was further classified into two, comprising 13 members each, according to the severity of the disease, and the gait behavior of the five groups was compared. We found that the normal, PD, and MCI/dementia groups show characteristic walking patterns which can be distinguished from one another by the developed gait measure set. We also examined conventional parameters such as gait acceleration, gait cycle, and gait variability, but failed to reproduce the distinct differences among the five groups. These findings suggest that the proposed gait analysis may be useful in capturing disease-specific gait features in a community setting.

Evaluation of postural balance in mild cognitive impairment through a three-dimensional electromagnetic system

Introduction

Elderly people with cognitive impairment are at greater risk for falls; thus, an understanding of the earliest stages of cognitive decline is necessary.

Objective

To compare postural balance between elderly people with and without mild cognitive impairment using a three-dimensional system.

Methods

Thirty elderly people with mild cognitive impairment and thirty healthy elderly subjects were selected. Static posturography was performed using three-dimensional electromagnetic equipment and the following parameters were evaluated: maximum displacement, mean speed and total trajectory. Open- and closed-eye stabilometric variable comparisons between groups and within each group were carried out, and a relationship between the Mini Mental State Examination and the total trajectory of all elderly subjects was determined.

Results

The analysis among open- and closed-eye conditions showed a significant difference in maximum anteroposterior displacement in the control group and a significant difference in all stabilometric variables in the mild cognitive impairment group. A significant difference between the groups in all variables in the closed-eye condition was observed. There was a strong correlation between cognitive performance and total trajectory.

Conclusion

Evaluations showed decrease in balance in elderly people with mild cognitive impairment. Presence of anteroposterior displacement can be an early sign of postural control impairment, and the evaluation with visual restriction can be useful in detecting small postural instabilities.

Vestibular Function Impairment in Alzheimer's Disease

BACKGROUND

Falls and fractures due to impaired balance in patients with Alzheimer's disease (AD) have an adverse effect on the clinical course of the disease.

OBJECTIVE

To evaluate balance impairment in AD from the viewpoint of vestibular functional impairment.

METHODS

The subjects were 12 patients with AD, 12 dementia-free elderly adults, and 12 younger adults. Vestibular function was assessed using a stepping test, caloric nystagmus, and a visual suppression (VS) test.

RESULTS

The stepping test was abnormal in 9 of the 12 patients in the AD group. An abnormal stepping test was not associated with self-reported dizziness or tendency to fall. Significant VS abnormalities were present in the AD group. The suppression rate of VS was lower in AD patients with either a tendency to fall or constructional apraxia than in AD patients without either. The velocity of the rapid phase of caloric nystagmus before the VS test was similar in the AD group and the elderly control group. Significant abnormalities of both caloric nystagmus and VS were not present in either the elderly or the younger control groups.

CONCLUSION

AD could involve impairments in the vestibular control of balance. The VS test is useful for assessing the tendency to fall in AD. Impairment of VS in AD might arise from cerebral vestibular cortex impairment rather than comorbid peripheral vestibular disorders.

The Impact of Mild Cognitive Impairment on Gait and Balance: A Systematic Review and Meta-Analysis of Studies Using Instrumented Assessment

BACKGROUND

In addition to cognitive deficits, people with mild cognitive impairment (MCI) can experience motor dysfunction, including deficits in gait and balance. Objective, instrumented motor performance assessment may allow the detection of subtle MCI-related motor deficits, allowing early diagnosis and intervention. Motor assessment under dual-task conditions may increase diagnostic accuracy; however, the sensitivity of different cognitive tasks is unclear.

OBJECTIVE

To systematically review the extant literature focusing on instrumented assessment of gait and balance parameters for discriminating MCI patients from cognitively intact peers.

METHODS

Database searches were conducted in PubMed, EMBASE, Cochrane Library, PsycINFO and Web of Science. Inclusion criteria were: (1) clinically confirmed MCI; (2) instrumented measurement of gait and/or balance; (3) English language, and (4) reporting gait or balance parameters which could be included in a meta-analysis for discriminating between MCI patients and cognitively intact individuals based on weighted effect size (d).

RESULTS

Fourteen studies met the inclusion criteria and reported quantitative gait (n = 11) or postural balance (n = 4) parameters to be included in the meta-analysis. The meta-analysis revealed that several gait parameters including velocity (d = -0.74, p < 0.01), stride length (d = -0.65, p < 0.01), and stride time (mean: d = 0.56, p = 0.02; coefficient of variation: d = 0.50, p < 0.01) discriminated best between MCI and healthy controls under single-task conditions. Importantly, dual-task assessment increased the discriminative power of gait variables wherein gait variables with counting tasks appeared to be more sensitive (range d = 0.84-1.35) compared to verbal fluency tasks such as animal naming (range d = 0.65-0.94). Balance parameters identified as significant discriminators were anterior-posterior (d = 0.49, p < 0.01) and mediolateral (d = -0.34, p = 0.04) sway position in the eyes-open condition but not eyes-closed condition.

CONCLUSION

Existing studies provide evidence that MCI affects specific gait parameters. MCI-related gait changes were most pronounced when subjects are challenged cognitively (i.e., dual task), suggesting that gait assessment with an additional cognitive task is useful for diagnosis and outcome analysis in the target population. Static balance seems to also be affected by MCI, although limited evidence exists. Instrumented motor assessment could provide a critical opportunity for MCI diagnosis and tailored intervention targeting specific deficits and potentially slowing progression to dementia. Further studies are required to confirm our findings.

Does upper limb coordination predict walking speed in older adults? A cross-sectional study

BACKGROUND AND PURPOSE

Walking speed is a measure of physical function in older adults. Older adults are sometimes nonambulatory, however, and proxy measures for walking speed may be indicated. Since limb coordination tests can be conducted in non-weight-bearing positions, they may provide that capability. The purpose of this study was to examine the relationship between timed limb coordination and preferred and maximum walking speed, controlling for other known determinants of walking speed.

METHODS

A total of 84 healthy adults (60 women and 24 men) older than 60 years participated. Preferred and maximum walking speed were measured during 10-Meter Walk Tests. Upper limb coordination performance was measured during a timed 5-repetition finger-to-nose test. Other variables measured included isometric knee extension strength, cognition (Montreal Cognitive Assessment), limits of stability (Functional Reach Test), the number of comorbidities (Functional Comorbidity Index), age, height, and sex. Multiple regression and partial correlation analyses (α = .05) were used to identify which variables predicted preferred and maximum walking speed, controlling for all other variables.

RESULTS

Participants' mean preferred walking speed was 129 (24) cm·s⁻¹, and mean maximum walking speed was 176 (37) cm·s⁻¹. Finger-to-nose coordination performance, 4.8 (1.3) seconds, correlated negatively with preferred (r = -0.403) and maximum (r = -0.429) walking speed. Those bivariate correlation coefficients, however, were attenuated by other variables in the regression models (partial r = -0.031, P = .786, and partial r = -0.075, P = .513, for preferred and maximum walking speed, respectively). Variance in age, comorbidities, functional reach, knee extension strength, and height accounted for 55.4% of the variance in preferred walking speed. Variance in knee extension strength, cognition, functional reach, age, and comorbidities accounted for 63.5% of the variance in maximum walking speed. After removing knee extension strength and functional reach from the models--those variables that may be difficult or contraindicated to measure in some patient populations--finger-to-nose coordination was not a statistically significant predictor of preferred walking speed. Variance in age, comorbidities, cognition, height, and finger-to-nose coordination accounted for 55.9% of the variance in maximum walking speed. The change in R² attributed to finger-to-nose coordination performance, however, was only 2.9%.

DISCUSSION

While knee extension strength, functional reach, comorbidities, and age were most predictive of walking speed, after removing knee extension strength and functional reach from the regression models, finger-to-nose coordination remained a potentially modifiable marker of neuromuscular control that only weakly predicted maximum walking speed in older adults.

CONCLUSIONS

The timed finger-to-nose test would not appear to be a valid proxy for walking speed when weight-bearing clinical examination procedures are contraindicated.

Sensor-derived physical activity parameters can predict future falls in people with dementia

BACKGROUND

There is a need for simple clinical tools that can objectively assess the fall risk in people with dementia. Wearable sensors seem to have the potential for fall prediction; however, there has been limited work performed in this important area.

OBJECTIVE

To explore the validity of sensor-derived physical activity (PA) parameters for predicting future falls in people with dementia. To compare sensor-based fall risk assessment with conventional fall risk measures.

METHODS

This was a cohort study of people with confirmed dementia discharged from a geriatric rehabilitation ward. PA was quantified using 24-hour motion-sensor monitoring at the beginning of the study. PA parameters (percentage of walking, standing, sitting, and lying; duration of single walking, standing, and sitting bouts) were extracted using specific algorithms. Conventional assessment included performance-based tests (Timed Up and Go Test, Performance-Oriented Mobility Assessment, 5-chair stand) and questionnaires (cognition, ADL status, fear of falling, depression, previous faller). Outcome measures were fallers (at least one fall in the 3-month follow-up period) versus non-fallers.

RESULTS

77 people were included in the study (age 81.8 ± 6.3; community-dwelling 88%, institutionalized 12%). Surprisingly, fallers and non-fallers did not differ on any conventional assessment (p = 0.069-0.991), except for 'previous faller' (p = 0.006). Interestingly, several PA parameters discriminated between the groups. The 'walking bout average duration', 'longest walking bout duration' and 'walking bout duration variability' were lower in fallers, compared to non-fallers (p = 0.008-0.027). The 'standing bout average duration' was higher in fallers (p = 0.050). Two variables, 'walking bout average duration' [odds ratio (OR) 0.79, p = 0.012] and 'previous faller' (OR 4.44, p = 0.007) were identified as independent predictors for falls. The OR for a 'walking bout average duration' <15 s for predicting fallers was 6.30 (p = 0.020). Combining 'walking bout average duration' and 'previous faller' improved fall prediction (OR 7.71, p < 0.001, sensitivity/specificity 72%/76%).

DISCUSSION

RESULTS demonstrate that sensor-derived PA parameters are independent predictors of the fall risk and may have higher diagnostic accuracy in persons with dementia compared to conventional fall risk measures. Our findings highlight the potential of telemonitoring technology for estimating the fall risk. RESULTS should be confirmed in a larger study and by measuring PA over a longer period of time.

Relationships between balance and cognition in patients with subjective cognitive impairment, mild cognitive impairment, and Alzheimer disease

BACKGROUND

Balance impairments are common in patients with Alzheimer disease (AD), but which aspects of balance are affected, at which stage of cognitive impairment, and their associations with cognitive domains remain unexplored.

OBJECTIVES

The aims of this study were: (1) to explore differences in balance abilities among patients with subjective cognitive impairment (SCI) or mild cognitive impairment (MCI), mild AD, and moderate AD and (2) to examine the relationship between the various aspects of balance and cognitive domains.

DESIGN

This was a cross-sectional study.

METHODS

Home-dwelling patients with SCI or MCI (n=33), mild AD (n=99), and moderate AD (n=38) participated in this study. The Balance Evaluation Systems Test (BESTest), comprising 6 subscales-"Biomechanical Constraints," "Stability Limits/Verticality," "Anticipatory Postural Adjustments," "Postural Responses," "Sensory Orientation," and "Stability in Gait"-was used to assess balance. Cognitive domains were assessed using the following measures: Mini-Mental Status Examination, Word-List Learning Test from the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), Verbal Fluency Test, Clock Drawing Test, and Trail Making Test, parts A and B (TMT-A and TMT-B, respectively). Two-way between-group analyses of variance, adjusted for age, were used to analyze differences among the groups. Multiple linear regression analysis was used to explore the associations between balance and cognition.

RESULTS

Differences were found between the groups on all BESTest subscales; the moderate AD group had the worst scores. The TMT-B (measuring executive function) was associated with all of the BESTest subscales after controlling for demographic factors.

LIMITATIONS

The cross-sectional design hampered interpretation of the development of balance impairments.

CONCLUSIONS

The study findings indicate that all aspects of balance control deteriorate with increasing severity of cognitive impairment and that executive function plays an important role in balance control. Physical therapists should pay attention to these findings both in clinical practice and in future research.

Physical performance is associated with working memory in older people with mild to severe cognitive impairment

BACKGROUND

Physical performances and cognition are positively related in cognitively healthy people. The aim of this study was to examine whether physical performances are related to specific cognitive functioning in older people with mild to severe cognitive impairment.

METHODS

This cross-sectional study included 134 people with a mild to severe cognitive impairment (mean age 82 years). Multiple linear regression was performed, after controlling for covariates and the level of global cognition, with the performances on mobility, strength, aerobic fitness, and balance as predictors and working memory and episodic memory as dependent variables.

RESULTS

The full models explain 49-57% of the variance in working memory and 40-43% of episodic memory. Strength, aerobic fitness, and balance are significantly associated with working memory, explaining 3-7% of its variance, irrespective of the severity of the cognitive impairment. Physical performance is not related to episodic memory in older people with mild to severe cognitive impairment.

CONCLUSIONS

Physical performance is associated with working memory in older people with cognitive impairment. Future studies should investigate whether physical exercise for increased physical performance can improve cognitive functioning. This trial is registered with ClinicalTrials.gov NTR1482.

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.

Postural control and cognitive decline in older adults: position versus velocity implicit motor strategy

The present study explored the impact of cognitive decline on postural control strategies in older adults with and without cognitive decline from mild cognitive impairment (MCI) to mild-to-moderate Alzheimer disease (MMAD). We hypothesized that the cognitive decline affected the postural control leading to higher bounding limits of COP velocity dynamics. Based on a cross-sectional design, 175 non-faller older adults were recruited in Angers University Hospital, France, including 50 cognitively healthy individuals [CHI] (mean age 76.42 ± 4.84 years; 30% women), 64 age- and body mass index-matched participants with MCI (mean age 77.51 ± 6.32 years; 39% women), and 61 age- and body mass index-matched participants with MMAD (mean age 78.44 ± 3.97 years; 62% women). For all data collection of postural sway, the participants were asked to maintain quiet stance on force platform. The postural test consisted of two trials of quiet stance, with eyes open and with eyes closed. The COP parameters were mean and standard deviation (SD) of position, velocity and average absolute maximal velocity (AAMV) in antero-posterior and medio-lateral directions. Overall, the analysis concerning all COP parameters revealed a significant main effect of cognitive status on velocity-based variables, with post hoc comparisons evidencing that SD velocity and AAMV increased with cognitive impairment. The current findings suggest an active control (or corrective process) of COP velocity dynamics for CHI, whereas MCI and MMAD are affected by COP movements.

Effectiveness of exercise on cognitive impairment and Alzheimer's disease

Physical activity has a protective effect on brain function in older people. Here, we briefly reviewed the studies and results related to the effects of exercise on cognitive impairment and Alzheimer's disease. The main findings from the current body of literature indicate positive evidence for structured physical activity (cardiorespiratory and resistance exercise) as a promising non-pharmacological intervention for preventing cognitive decline. More studies are needed to determine the mechanisms involved in this preventative effect, including on strength, cardiorespiratory, and other types of exercise. Thus, the prevention of Alzheimer's disease may depend on healthy lifestyle habits, such as a structured physical fitness program.

Older women with dementia can perform fast alternating forearm movements and performance is correlated with tests of lower extremity function

BACKGROUND

The purpose of this work was to study the performance and reliability of a test of fast alternating forearm movements and its relationship with measures of lower extremity function in older women with dementia.

METHODS

Fast alternating movements was studied in 26 female patients (mean age 81.7 ± 5.9 years) with dementia and 34 controls (mean age 87.5 ± 4.7 years). Subgroup analyses for those aged 80-89 years were performed due to significant differences in the mean ages of the study groups. Test-retest reliability for alternating forearm movements was studied in 11 patients (mean age 80.3 ± 6.7 years) and 10 controls (mean age 87.4 ± 1.6 years). Pulses generated were transformed to an analog signal shown on a modified electrocardiogram. Numbers of cycles at 10 and 15 seconds were calculated for the right and left hand. Walking 2 × 15 m and the Get-Up-and Go (GUG) test were performed at self-selected and maximal speed. Associations between tests of upper and lower extremity function were sought in eight patients (mean age 85 ± 2.7 years) and 16 controls (mean age 85.1 ± 2.8 years) and also according to types of dementia in nine patients with probable Alzheimer's disease and 10 patients with other types of dementia.

RESULTS

Patients with dementia could perform the test and had significantly fewer cycles (P = 0.02-0.006) at both 10 and 15 seconds compared with controls after age adjustment. A higher number of cycles was associated with higher self-selected walking speeds in patients (r = -0.79). Test-retest reliability for alternating forearm movements was high for both patients (intraclass correlation 0.88-0.94) and controls (intraclass correlation 0.74-0.94).

CONCLUSION

Alternating forearm movements at fast speed can be used as a reliable test in both patients with dementia and healthy older subjects. The test can be used as a measure of bradykinesia and might be useful as a proxy for lower extremity function in older persons with dementia when testing of the lower extremities is not applicable due to walking disability.

Pilot study into impaired judgement, self-toileting behaviour in fallers and non-fallers

Falls are a significant cause of morbidity and mortality in older people. There is an increased frequency of falls in older adults with cognitive impairment and dementia which may be due to impaired judgement of self capability to mobilise safely. This case control study assessed 53 Aged Care subjects aged 75+ years that were hospitalised post fall, from January 2008-December 2009, and compared these subjects' responses to those of 26 non-fallers to a standard question: 'While you are in the hospital, what would you do if you need to go to the toilet later?' This hypothetical scenario question was designed to assess judgement based on self-toileting behaviour and mobility. The study group and control group were similar in age (83.9 ± 4.7 vs. 82.0 ± 4.6 years respectively, p = 0.081) but the study group had statistically lower MMSE results when compared to controls (median 23 vs. 26.5 respectively, p = 0.031). Impaired judgement, defined as an unsafe/inappropriate response to the scenario question, was significantly more prevalent in the study group (fallers) compared to the control group (non-fallers) (41.5 vs. 15.4 %, p = 0.020). Impaired judgement was also more common with lower MMSE scores with 80.9 % of unsafe/inappropriate responses given by participants with MMSE of ≤20. The authors suggest there may be an association between impaired judgement, evidenced by responses to a standardised question, and falls history in older subjects, particularly in those with cognitive impairment or dementia. Ultimately, this may lead to identification of people at increased risk of falls and possibly effective falls prevention strategies in this population.