The Role of Cognitive Factors in Predicting Balance and Fall Risk in a Neuro-Rehabilitation Setting

Time-Varying Hazard of Patient Falls in Hospital: A Retrospective Case-Control Study

This study aims to evaluate the association between patient falls and relevant factors and to quantify their effect on fall risk. This is a retrospective case-control study using the secondary data collected from a tertiary general hospital. Study subjects were 450 patients who were admitted to the hospital between January 2016 and December 2020. The prevalence of falls was associated with the fall risk level by the Morse Fall Scale (MFS) and individual status at admission including history of admission, dizziness, sleep disorder, bowel dysfunction, and urinary incontinence. The odds ratios of patient falls were higher in the low-risk group by the MFS score (odds ratio (OR) = 2.61, p < 0.001) and the high-risk group (OR = 5.51, p < 0.001) compared to the no-risk group. The hazard ratio of patient falls was higher in the high-risk group by the MFS score (hazard ratio (HR) = 3.85, p < 0.001). The MFS had a significant explanatory power to predict fall risk. Sleep disorder and urinary incontinence were the significant factors influencing patient falls.

Receiver Operating Characteristic Curve Analysis of the Somatosensory Organization Test, Berg Balance Scale, and Fall Efficacy Scale–International for Predicting Falls in Discharged Stroke Patients

Background: Although fall prevention in patients after stroke is crucial, the clinical validity of fall risk assessment tools is underresearched in this population. The study aim was to determine the cut-off scores and clinical validity of the Sensory Organization Test (SOT), the Berg Balance Scale (BBS), and the Fall Efficacy Scale–International (FES-I) in patients after stroke. Methods: In this prospective cross-sectional study, we analyzed data for patients admitted to a rehabilitation unit after stroke from 2018 through 2021. Participants underwent SOT, BBS, and FES-I pre-discharge, and the fall incidence was recorded for 6 months. We used an area under the receiver operating characteristic curve (AUC) to calculate predictive values. Results: Of 84 included patients (median age 68.5 (interquartile range 67–71) years), 32 (38.1%) suffered a fall. All three tests were significantly predictive of fall risk. Optimal cut-off scores were 60 points for SOT (AUC 0.686), 35 and 42 points for BBS (AUC 0.661 and 0.618, respectively), and 27 and 29 points for FES-I (AUC 0.685 and 0.677, respectively). Conclusions: Optimal cut-off scores for SOT, BBS, and FES-I were determined for patients at risk for falls after a stroke, which all three tools classified with a good discriminatory ability.

Stability of Balance Performance From Childhood to Midlife

BACKGROUND

Balance ability underlies most physical movement across life, with particular importance for older adults. No study has investigated if balance ability is established in childhood nor if associations are independent of adult factors. We investigated associations between balance performance in early (age 10) and midlife (age 46), and whether associations were independent of contributors to adult balance.

METHODS

Up to 6024 individuals from the 1970 British Cohort Study were included. At age 10, static (1-legged stand) and dynamic (backward toe-to-heel walk) balance were categorized as poor, medium, or high. Eyes open and closed 1-legged balance performance (max: 30 seconds) was assessed at age 46 with 5 categories.

RESULTS

Poor static balance at age 10 was strongly associated with worse balance ability at age 46. Relative to the highest balance group at age 46 (ie, eyes open and closed for 30 seconds), those with poor static balance had a 7.07 (4.92-10.16) greater risk of being in the poorest balance group (ie, eyes open <15 seconds). Associations were robust to adjustment for childhood illness, cognition, and socioeconomic position and adult measures of height, BMI, education, exercise, word recall, and grip strength (adjusted relative risk: 5.04 [95% confidence interval: 3.46-7.37]). Associations between dynamic balance at age 10 and balance at age 46 were weaker (adjusted relative risk) of the poorest balance group: 1.84 [1.30-2.62]).

CONCLUSIONS

Early childhood may represent an important period for maturation of postural strategies involved in balance, indicating the potential for early intervention and policy changes alongside existing interventions that currently target older adults.

Cognitive inhibition tasks interfere with dual-task walking and increase prefrontal cortical activity more than working memory tasks in young and older adults

BACKGROUND

Prior work suggests there may be greater reliance on executive function for walking in older people. The pre-frontal cortex (PFC), which controls aspects of executive function, is known to be active during dual-task walking (DTW). However, there is debate on how PFC activity during DTW is impacted by ageing and the requirements of the cognitive task.

RESEARCH QUESTION

Functional near infrared spectroscopy, was used to investigate how PFC activity during walking was affected by (i) healthy ageing; and (ii) dual-tasks that utilise inhibition or working memory aspects of executive function.

METHODS

Young (n = 26, 16 females, mean 20.9 years) and older (n = 26, 16 females, mean 70.3 years) adults performed five conditions: normal walking; Reciting Alternate Letters of the alphabet (RAL, requiring cognitive inhibition and working memory) during standing and walking; and serial subtraction by threes (SS3, requiring working memory alone) during standing and walking. Walking speed, cognitive performance, the PFC haemodynamic response, and fear of falling ratings were analysed using linear mixed-effects modelling.

RESULTS

Compared to quiet standing, PFC activity increased during normal walking for older adults but decreased for young adults (p < 0.01). Across both groups, fear of falling contributed to higher PFC activity levels when walking (p < 0.01). PFC activity increased during DTW, and this increase was greater when performing RAL compared to the SS3 task (p < 0.01). Although the rate of correct responses was higher for RAL, walking speed reduced more with RAL than SS3 in the young group (p = 0.01), and the rate of correct responses reduced more when walking with RAL than SS3 in the older group (p < 0.01).

SIGNIFICANCE

Older adults have increased levels of PFC activation during walking compared to younger adults and fear of falling is a cofounding factor. The interference between gait and a concurrent cognitive task is higher when the cognitive task requires inhibition.

Associations of Word Memory, Verbal Fluency, Processing Speed, and Crystallized Cognitive Ability With One-Legged Balance Performance in Mid- and Later Life

BACKGROUND

Cognitive integration of sensory input and motor output plays an important role in balance. Despite this, it is not clear if specific cognitive processes are associated with balance and how these associations change with age. We examined longitudinal associations of word memory, verbal fluency, search speed, and reading ability with repeated measures of one-legged balance performance.

METHOD

Up to 2 934 participants in the MRC National Survey of Health and Development, a British birth cohort study, were included. At age 53, word memory, verbal fluency, search speed, and reading ability were assessed. One-legged balance times (eyes closed) were measured at ages 53, 60-64, and 69 years. Associations between each cognitive measure and balance time were assessed using random-effects models. Adjustments were made for sex, death, attrition, height, body mass index, health conditions, health behaviors, education, and occupational class.

RESULTS

In sex-adjusted models, 1 SD higher scores in word memory, search speed, and verbal fluency were associated with 14.1% (95% CI: 11.3, 16.8), 7.2% (4.4, 9.9), and 10.3% (7.5, 13.0) better balance times at age 53, respectively. Higher reading scores were associated with better balance, although this association plateaued. Associations were partially attenuated in mutually adjusted models and effect sizes were smaller at ages 60-64 and 69. In fully adjusted models, associations were largely explained by education, although remained for word memory and search speed.

CONCLUSIONS

Higher cognitive performance across all measures was independently associated with better balance performance in midlife. Identification of individual cognitive mechanisms involved in balance could lead to opportunities for targeted interventions in midlife.

Screening recall in older cancer survivors detects differences in balance and mobility

PURPOSE

Cognitive impairments have been reported by up to two-thirds of cancer survivors whose primary cancer did not occur in the central nervous system. Physical impairments as sequelae of cancer-related cognitive impairment (CRCI) have not been well described in previous studies. Furthermore, there is scarcity of literature describing differences among physical performance in those with and without CRCI. The purpose of this study is to examine the differences in physical function of older cancer survivors based on cognitive ability to determine if physical performance differs when different cognitive screening measures are employed.

METHODS

Adults age 65 + with a history of cancer from the 2010 Health and Retirement Study (n = 1,953) were assigned to groups according to their cognitive ability. Between-group demographic, mobility, and cognitive differences were analyzed using chi-squared and t tests. Recall and orientation were used as cognitive variables, and physical performance outcomes included gait speed, balance, and grip strength.

RESULTS

Respondents with Low Recall had more impaired balance (semi-tandem, tandem) (p < .05) and slower gait speeds (p < .05). Respondents that were Not-Oriented had slower gait speed (p < .05). Between-group differences in demographics were found by recall and orientation groups.

CONCLUSIONS

Impairments in balance and gait speed are able to be detected when recall is screened in a population of older cancer survivors. When assessing how physical mobility is related to fall risk, a screen of cognition should go beyond just orientation.

Relating Global Cognition With Upper-Extremity Motor Skill Retention in Individuals With Mild-to-Moderate Parkinson's Disease

Background and Purpose: Cognition has been linked to rehabilitation outcomes in stroke populations, but this remains unexplored in individuals with Parkinson's disease (PD). The purpose of this secondary data analysis from a recent clinical trial (NCT02600858) was to determine if global cognition was related to skill performance after motor training in individuals with PD. Methods: Twenty-three participants with idiopathic PD completed 3 days of training on an upper-extremity task. For the purposes of the original clinical trial, participants trained either "on" or "off" their dopamine replacement medication. Baseline, training, and 48-h retention data have been previously published. Global cognition was evaluated using the Montreal Cognitive Assessment (MoCA). Linear regression examined whether MoCA score predicted longer-term retention at nine-day follow-up; baseline motor task performance, age, PD severity, depressive symptoms, and group (medication "on"/"off") were included as covariates. Baseline and follow-up motor task performance were assessed for all participants while "on" their medication. Results: MoCA score was positively related to follow-up motor task performance, such that individuals with better cognition were faster than those with poorer cognition. Baseline task performance, age, PD severity, depressive symptoms, and medication status were unrelated to follow-up performance. Discussion and Conclusions: Results of this secondary analysis align with previous work that suggest cognitive impairment may interfere with motor learning in PD and support the premise that cognitive training prior to or concurrent with motor training may enhance rehabilitative outcomes for individuals with PD. Findings also suggest that assessing cognition in individuals with PD could provide prognostic information about their responsiveness to motor rehabilitation.

Video game therapy on mobility and dual tasking in multiple sclerosis: study protocol for a randomised controlled trial

INTRODUCTION

Multiple sclerosis (MS) is one of the major causes of disability in young adults and affects mobility, compromising daily living activities and participation in social life. Cognitive domain is also frequently impaired in people with MS (PwMS), particularly the capacity to perform dual-task activities. Impaired cognitive processing abilities need to be treated, and motor and cognitive aspects need to be considered together. Recently, video game therapy (VGT) has been used in rehabilitation to improve motor outcomes and cognitive processing speed. The aim of this study is to test the efficacy of commercially available VGT on mobility and dual tasking in PwMS compared with standardised balance platform training (BPT).

METHODS AND ANALYSIS

This will be a parallel-assignment, double-blinded, randomised control trial. Forty-eight (24 per arm) PwMS with Expanded Disability Status Scale 4-5.5 will be randomly assigned to receive 1 hour training session over 4 weeks (three sessions/week) of either: (1) VGT on commercial video game console to train balance and mobility-related activities or (2) BPT to perform balance, postural stability and weight-shifting exercises with and without visual feedback. The same assessor will evaluate outcome measures at points: before and after the 12 training sessions and at 3 months of follow-up. The primary outcome will be functional mobility, assessed by the Timed Up and Go test. We will also evaluate gait, risk of fall, fatigue and health-related quality of life as well as cognitive and psychological aspects (depression, anxiety and attentional performance) and stability through posturographic evaluation. Dual-tasking assessment will be performed combining posturographic and neuropsychological tests. Data analysis will be performed to compare the efficacy of the two treatments.

ETHICS AND DISSEMINATION

Ethical approval have been granted from the local Ethics Committee. Study results will be communicated through high-quality journals and national and international conferences.

TRIAL REGISTRATION NUMBER

NCT03353974.

Relationship between Speed of Response Inhibition and Ability to Suppress a Step in Midlife and Older Adults

In young adults, performance on a test of response inhibition was recently found to be correlated with performance on a reactive balance test where automated stepping responses must occasionally be inhibited. The present study aimed to determine whether this relationship holds true in older adults, wherein response inhibition is typically deficient and the control of postural equilibrium presents a greater challenge. Ten participants (50+ years of age) completed a seated cognitive test (stop signal task) followed by a reactive balance test. Reactive balance was assessed using a modified lean-and-release system where participants were required to step to regain balance following perturbation, or suppress a step if an obstacle was present. The stop signal task is a standardized cognitive test that provides a measure of the speed of response inhibition called the Stop Signal Reaction Time (SSRT). Muscle responses in the legs were compared between conditions where a step was allowed or blocked to quantify response inhibition of the step. The SSRT was significantly related to leg muscle suppression during balance recovery in the stance leg. Thus, participants that were better at inhibiting their responses in the stop signal task were also better at inhibiting an unwanted leg response in favor of grasping a supportive handle. The relationship between a seated cognitive test using finger responses and leg muscle suppression when a step was blocked indicates a context-independent, generalized capacity for response inhibition. This suggests that a simple cognitive test such as the stop signal task could be used clinically to predict an individual’s capacity for adapting balance reactions and fall risk. The present results provide support for future studies, with larger samples, to verify this relationship between stop signal reaction time and leg response during balance recovery.

Bidirectional associations between word memory and one-legged balance performance in mid and later life

BACKGROUND

Age-related changes in cognitive and balance capabilities are well-established, as is their correlation with one another. Given limited evidence regarding the directionality of associations, we aimed to explore the direction and potential explanations of associations between word memory and one-legged balance performance in mid-later life.

METHODS

A total of 3062 participants in the Medical Research Council National Survey of Health and Development, a British birth cohort study, were included. One-legged balance times (eyes closed) were measured at ages 53, 60-64 and 69 years. Word memory was assessed at ages 43, 53, 60-64 and 69 with three 15-item word-recall trials. Autoregressive cross-lagged and dual change score models assessed bidirectional associations between word memory and balance. Random-effects models quantified the extent to which these associations were explained by adjustment for anthropometric, socioeconomic, behavioural and health status indicators.

RESULTS

Autoregressive cross-lagged and dual change score models suggested a unidirectional association between word memory and subsequent balance performance. In a sex-adjusted random-effects model, 1 standard deviation increase in word memory was associated with 9% (7,12%) higher balance performance at age 53. This association decreased with age (-0.4% /year (-0.6,-0.1%). Education partially attenuated the association, although it remained in the fully-adjusted model (3% (0.1,6%)).

CONCLUSIONS

There was consistent evidence that word memory is associated with subsequent balance performance but no evidence of the reverse association. Cognitive processing plays an important role in the balance process, with educational attainment providing some contribution. These findings have important implications for understanding cognitive-motor associations and for interventions aimed at improving cognitive and physical capability in the ageing population.

Do motor-cognitive and motor-motor dual task training effect differently balance performance in older adults?

PURPOSE

Dual-task training (DTT) have been showed that have satisfying effects on older adults. The aim of this study was to compare the effect of motor-cognitive DTT (mCdtt) and motor-motor DTT (mMdtt) on balance, fear of falling, walking functionality and muscle strength in older adults.

METHODS

A total of 50 participants aged 60 and over (mean age: 67.72 ± 7.33 years), having a score ≥ 24 on the Mini-Mental State Exam (MMSE), being in the category of walking ability ≥ 4 according to the Functional Ambulation Category (FAC), having no problem in visual ability and hearing were included for this study. The participants who received mCdtt (Group 1) counted back from the two-digit number; and the participants who received mMdtt (Group 2) held half-filled glasses with both hands near the trunk with 90° flexion of elbow while performing exercises. The intervention program had lasted for 8 weeks. To assess balance, fear of falling, walking functionality and muscle strength of participants; Berg Balance Scale (BBS), Falls Efficacy Scale International (FES-I), Timed Up and Go (TUG) and the Hand-held dynamometer were used, respectively.

RESULTS

The results of our study showed that 8-week mCdtt and mMdtt program did not differ in balance fear of falling, walking functionality and muscle strength in older adults, although both trainings had improved balance ability.

CONCLUSION

It can be interpreted that both training programs can be suggested to enhance abovementioned parameters in older adults. Further studies are needed to elucidate the difference of clinical outcomes between the mCdtt and mMdtt program in older adults.

TRIAL REGISTRATION NUMBER

NCT04577092.

DATE OF REGISTRATION

09/30/2020 "Retrospectively registered".

The role of impulsivity in neurorehabilitation: A prospective cohort study of a potential cognitive biomarker for fall risk?

BACKGROUND

Executive dysregulation and impulsivity can both predispose individuals to risk-prone actions. Although the risk of falls is well established in people with poor executive function, its association to impulsivity is less clear.

PURPOSE

To describe and assess the prognostic capabilities of the relationship between impulsivity, executive function, functional capability, and falls in the in-patient neurorehabilitation population.

MATERIALS AND METHODS

A prospective cohort study in a 26-bed neurorehabilitation unit in London, recruiting 121 patients, of whom 94 were deemed eligible for inclusion. Cognitive-behavioural assessment was undertaken using the short (16-item) version of the Urgency-Premeditation-Perseverance-Sensation Seeking-Positive Urgency (UPPS) impulsive behaviour scale, and the Trail Making Test (TMT). Patients also underwent a functional assessment at admission and discharge using the UK Functional Independence and Assessment Measure tool (FIM + FAM). The main outcome of interest was falling during an in-patient episode, which are routinely recorded in a computerized registry of adverse incidents.

RESULTS

Measurements of impulsivity (based on the UPPS-Short form) and executive function (based on the Trail Making Test) were not found to be significantly associated with functional improvement, or risk of falling. Predictive modelling experiments demonstrated that neither of the aforementioned results were capable of identifying individuals at risk of falling more accurately than an informed guess.

CONCLUSION

Where impulsivity is present, measurement using structured tools such as the UPPS may be informative to guide individualized rehabilitation programmes; however, its usefulness as the basis of risk prediction models for falls is less likely given the results of this study.

Post-stroke cognitive impairments and responsiveness to motor rehabilitation: A review

PURPOSE OF REVIEW

a)This review discusses the prevalence of cognitive deficits following stroke and their impact on responsiveness to therapeutic intervention within a motor learning context.

RECENT FINDINGS

b)Clinical and experimental studies have established that post-stroke cognitive and motor deficits may impede ambulation, augment fall risk, and influence the efficacy of interventions. Recent research suggests the presence of cognitive deficits may play a larger role in motor recovery than previously understood.

SUMMARY

c)Considering that cognitive impairments affect motor relearning, post-stroke motor rehabilitation therapies may benefit from formal neuropsychological testing. For example, early work suggests that in neurotypical adults, cognitive function may be predictive of responsiveness to motor rehabilitation and cognitive training may improve mobility. This sets the stage for investigations probing these topics in people post-stroke. Moreover, the neural basis for and extent to which these cognitive impairments influence functional outcome remains largely unexplored and require additional investigation.

Executive Functions Are Associated with Fall Risk but not Balance in Chronic Cerebrovascular Disease

BACKGROUND

Older people's deficits in executive functions (EF) have been shown to lead to higher fall risk, postural sway, and reduced speed. Crucially, EF impairments are even more pronounced in individuals with chronic cerebrovascular disease (CVD), namely vascular cognitive impairment.

METHODS

In this retrospective cross-sectional study, we used a complete neuropsychological battery, including the Trail Making Test (TMT) and physical measures, such as the Morse fall and EQUI scales, to assess 66 individuals with chronic CVD. Linear regressions, Bayesian analyses, and model selection were performed to see the impact of EF, global cognition, and vascular parkinsonism/hemiplegia on physical measures (fall risk and balance).

RESULTS

The TMT part B and BA correlated (r = 0.44 and r = 0.45) with Morse fall scale. Only EF significantly explained fall risk, whereas global cognition and vascular parkinsonism/hemiplegia did not. These findings were confirmed by Bayesian evidence and parsimony model selection. Balance was not significantly correlated with any of the neuropsychological tests.

CONCLUSIONS

This is the first study investigating the relationship between cognitive and physical measures in a sample of older people with chronic CVD. The results are consistent with previous findings that link EF with fall risk in CVD.

Free-Weight Resistance Exercise Is More Effective in Enhancing Inhibitory Control than Machine-Based Training: A Randomized, Controlled Trial

Resistance exercise has been demonstrated to improve brain function. However, the optimal workout characteristics are a matter of debate. This randomized, controlled trial aimed to elucidate differences between free-weight (RE_free) and machine-based (RE_mach) training with regard to their ability to acutely enhance cognitive performance (CP). A total of n = 46 healthy individuals (27 ± 4 years, 26 men) performed a 45-min bout of RE_free (military press, barbell squat, bench press) or RE_mach (shoulder press, leg press, chest press). Pre- and post-intervention, CP was examined using the Stroop test, Trail Making Test and Digit Span test. Mann-Whitney U tests did not reveal between-group differences for performance in the Digit Span test, Trail Making test and the color and word conditions of the Stroop test (p > 0.05). However, RE_free was superior to RE_mach in the Stroop color-word condition (+6.3%, p = 0.02, R = 0.35). Additionally, RE_free elicited pre-post changes in all parameters except for the Digit Span test and the word condition of the Stroop test while RE_mach only improved cognitive performance in part A of the Trail Making test. Using free weights seems to be the more effective RE method to acutely improve cognitive function (i.e., inhibitory control). The mechanisms of this finding merit further investigation.

Predictors of balance in older hip fracture patients undergoing standard motor rehabilitation

PURPOSE

Little is known about the factors predicting balance in hip fracture patients. The aim of this retrospective observational study was to assess balance before and after inpatient rehabilitation and, secondarily, to identify factors predicting the balance levels in older hip fracture patients after motor rehabilitation.

METHODS

Data were collected in 124 hip fracture patients over a 2-year period. All patients underwent a standard motor rehabilitation program. A modified version of Berg Balance Scale (BBS) score after rehabilitation, daily gain and percentage of improvement in BBS were the outcome measures. Multivariate regression analysis was performed to identify the predictors of balance.

RESULTS

The mean BBS score was 8.33 ± 7.23 at admission and 21.79 ± 12.15 at the end of rehabilitation (p < 0.001). The daily gain in BBS score was 0.39 ± 0.31 and the percent improvement was 32.28 ± 23.04%. Standing with one foot in front and standing on one foot were the BBS items with the lowest score at discharge and the lowest daily gain and percent improvement. The Cognitive-Functional Independence Measure (cognitive-FIM), hip muscles strength, and Katz index at discharge had moderate-to-strong relationships with final score, daily gain and percentage of improvement in BBS. Cognitive-FIM was a predictor of final BBS score (beta 0.49, p < 0.001), daily gain in BBS (beta 0.34, p < 0.001) and percent improvement in BBS (beta 0.44, p < 0.001). Conversely, hip muscles strength was a predictor of final BBS score (beta 0.32, p = 0.001), and Cumulative Illness Rating Scale severity, a predictor of daily gain in BBS (beta -0.29, p = 0.001). The R² value of the models were, respectively, 0.39, 0.23, and 0.19.

CONCLUSIONS

Cognitive function, comorbidities and hip muscles strength are important predictors of balance in hip fracture patients. Knowledge of these specific factors can be useful for physicians to identify patients needing specific rehabilitation programs for balance.

Postural Control during Progressively Increased Balance-Task Difficulty in Athletes with Unilateral Transfemoral Amputation: Effect of Ocular Mobility and Visuomotor Processing

This study examined postural control during single leg stance test with progressively increased balance-task difficulty in soccer players with unilateral transfemoral amputation (n = 11) compared to able-bodied soccer players (n = 11). The overall stability index (OSI), the anterior/posterior stability index, and the medial/lateral stability index during three balance tasks with increasing surface instability were estimated. The oculomotor and visuomotor contribution to postural control in disabled athletes was analyzed. Oculomotor function, simple and choice reaction times, and peripheral perception were assessed in a series of visuomotor tests. The variation in OSI demonstrated significantly greater increases during postural tests with increased balance-task difficulty in the able-bodied soccer players compared to amputees (F_(2,40) = 3.336, p < 0.05). Ocular mobility index correlated (p < 0.05) with OSI in conditions of increasing balance-task difficulty. Moreover, speed of eye-foot reaction has positive influence (p < 0.05) on stability indexes in tasks with an unstable surface. Amputee soccer players displayed comparable postural stability to able-bodied soccer players. Disabled athletes had better adaptability in restoring a state of balance in conditions of increased balance-task difficulty than the controls. The speed of visuomotor processing, characterized mainly by speed of eye-foot reaction, significantly contributed to these results.

Cognition assessments to predict inpatient falls in a subacute stroke rehabilitation setting

Background: Stroke-related falls occur at especially high rates in rehabilitation settings. Inpatient-hospital falls have been identified as one of the most common medical complications after stroke, negatively influencing recovery, nevertheless, the role of cognition in relation to falls during inpatient rehabilitation is largely unexplored. Objective. We aim to predict inpatient falls in a subacute stroke rehabilitation setting using previously reported variables such as stroke severity, gender, age, ataxia, hemiparesis, and functionality in activities of daily living, further extending them with specific cognition variables assessing memory, verbal fluency, attention, and orientation. Methods: This observational study included 158 stroke patients admitted to a rehabilitation center between 2007 and 2019, with less than 30 days since stroke onset to admission. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS). Four logistic regressions were performed including NIHSS, age, sex, ataxia, and hemiparesis plus one of the following: (1) Functional Independence Measure cognitive (C-FIM) and motor (M-FIM) subtests. (2) individual C-FIM items, (3) Ray Auditory Verbal Memory Test (RAVLT) and (4) verbal fluency test (PMR), Digit Span from Wechsler Adult Intelligence Scale (WAIS III), and Orientation from Test Barcelona. Results: Neither NIHSS, age, sex, ataxia nor hemiparesis predicted falls. C-FIM was a significant predictor (AUC:0.891), but not M-FIM. The problem solving C-FIM item (AUC:0.836), the RAVLT learning subtest (AUC:0.879), and PMR verbal fluency (AUC:0.871) were significant predictors for each model, respectively. Conclusions: Cognition assessments, i.e., one FIM item, one RAVLT item, or a one-minute verbal fluency test are significant falls predictors.

A Modified Lean and Release Technique to Emphasize Response Inhibition and Action Selection in Reactive Balance

Assessment of reactive balance traditionally imposes some type of perturbation to upright stance or gait followed by measurement of the resultant corrective behavior. These measures include muscle responses, limb movements, ground reaction forces, and even direct neurophysiological measures such as electroencephalography. Using this approach, researchers and clinicians can infer some basic principles regarding how the nervous system controls balance to avoid a fall. One limitation with the way in which these assessments are currently used is that they heavily emphasize reflexive actions without any need to revise automatic postural reactions. Such an exclusive focus on these highly stereotypical reactions would fail to adequately address how we can modify these reactions should the need arise (e.g., avoiding an obstacle with a recovery step). This would appear to be a glaring omission when one considers the enormous complexity of the environments we face daily. Overall, the status quo when evaluating the neural control of balance fails to truly expose how higher brain resources contribute to preventing falls in complex settings. The present protocol offers a way to require suppression of automatic, but inappropriate corrective balance reactions, and force a selection among alternative action choices to successfully recover balance following postural perturbation.

Perceptual Inhibition Associated with Sensory Integration for Balance in Older Adults

AIMS

Inhibition associated with perception has been implicated in sensory integration processes for balance when sensory conflict occurs. The current study examines the associations of three measures of inhibition (perceptual inhibition, motor inhibition, and Stroop interference) with standing balance under sensory conflict conditions in younger and older adults.

METHODS

Perceptual inhibition, motor inhibition, and Stroop interference were measured in younger and older subjects. Standing balance under conditions of sensory conflict was evaluated using a modified dynamic posturography protocol. Correlative analysis was performed to examine the associations between the inhibition measures and sway.

RESULTS

In older adults only, perceptual inhibition was correlated with sway when sensory conflict was present. Stroop interference and motor inhibition were not significantly correlated with sway under any posturography conditions.

CONCLUSION

Measures of perceptual inhibition are associated with reduced sensory integration capability for balance during sensory conflict conditions in older adults.

The Beneficial Effects of Mind-Body Exercises for People With Mild Cognitive Impairment: a Systematic Review With Meta-analysis

OBJECTIVE

To objectively evaluate the most common forms of mind-body exercise (MBE) (tai chi, yoga, qigong) on cognitive function among people with mild cognitive impairment (MCI).

DATA SOURCES

We searched 6 electronic databases (Scopus, PubMed, PsycINFO, WanFang, Web of Science, CNKI) from inception until September 2018.

STUDY SELECTION

Nine randomized controlled trials and 3 nonrandomized controlled trials were included for meta-analysis.

DATA EXTRACTION

Two researchers independently performed the literature searches, study selection, data extraction, and methodological quality assessment using the revised Physiotherapy Evidence Database (PEDro) scale.

DATA SYNTHESIS

The pooled effect size (standardized mean difference [SMD]) was calculated while random-effect model was selected. Overall results of the meta-analysis (N=1298 people with MCI) indicated that MBE significantly improved attention (SMD=0.39, 95% confidence interval [CI] 0.07-0.71, P=.02, I²=31.6%, n=245), short-term memory (SMD=0.74, 95% CI 0.57-0.90, P<.001, I²=0%, n=861), executive function (SMD=-0.42, 95% CI -0.63 to -0.21, P<.001, I²=38.54%, n=701), visual-spatial/executive function (SMD=0.35, 95% CI 0.07-0.64, P<.05, I²=0%, n=285), and global cognitive function (SMD=0.36, 95% CI 0.2-0.52, P<.001, I²=15.12%, n=902). However, the significant positive effect on cognitive processing speed was not observed following MBE interventions (SMD=0.31, 95% CI -0.01 to 0.63, P=.054, I²=28.66%, n=233).

CONCLUSIONS

Study findings of this meta-analysis suggest that MBE have the potential to improve various cognitive functions in people with MCI.

The Effects of Tai Chi on Markers of Atherosclerosis, Lower-limb Physical Function, and Cognitive Ability in Adults Aged Over 60: A Randomized Controlled Trial

Objective: The purpose of this study was to investigate the effects of Tai Chi (TC) on arterial stiffness, physical function of lower-limb, and cognitive ability in adults aged over 60. Methods: This study was a prospective and randomized 12-week intervention trial with three repeated measurements (baseline, 6, and 12 weeks). Sixty healthy adults who met the inclusion criteria were randomly allocated into three training conditions (TC-24, TC-42, and TC-56) matched by gender, with 20 participants (10 males, 10 females) in each of the three groups. We measured the following health outcomes, including markers of atherosclerosis, physical function (leg power, and static and dynamic balance) of lower-limb, and cognitive ability. Results: When all three TC groups (p < 0.05) have showed significant improvements on these outcomes but overall cognitive ability at 6 or 12 weeks training period, TC-56 appears to have superior effects on arterial stiffness and static/dynamic balance in the present study. Conclusions: Study results of the present study add to growing body of evidence regarding therapeutic TC for health promotion and disease prevention in aging population. Future studies should further determine whether TC-42 and TC-56 are beneficial for other non-Chinese populations, with rigorous research design and follow-up assessment.

A systematic review of falls in hospital for patients with communication disability: Highlighting an invisible population

BACKGROUND

Patients with communication disability, associated with impairments of speech, language, or voice, have a three-fold increased risk of adverse events in hospital. However, little research yet examines the causal relationship between communication disability and risk for specific adverse events in hospital.

OBJECTIVE

To examine the impact of a patient's communication disability on their falls risk in hospital.

METHODS

This systematic review examined 61 studies on falls of adult hospital patients with communication disability, and patients at high risk of communication disability, to determine whether or not communication disability increased risk for falls, and the nature of and reasons for any increased risk.

RESULTS

In total, 46 of the included studies (75%) reported on participants with communication disability, and the remainder included patients with health conditions placing them at high risk for communication disability. Two thirds of the studies examining falls risk identified communication disability as contributing to falls. Commonly, patients with communication disability were actively excluded from participation; measures of communication or cognition were not reported; and reasons for any increased risk of falls were not discussed.

CONCLUSIONS

There is some evidence that communication disability is associated with increased risk of falls. However, the role of communication disability in falls is under-researched, and reasons for the increased risk remain unclear. Practical applications: Including patients with communication disability in falls research is necessary to determine reasons for their increased risk of adverse events in hospital. Their inclusion might be helped by the involvement of speech-language pathologists in falls research teams.

Cognitive Effects of Perioperative Pregabalin

EDITOR’S PERSPECTIVE

What We Already Know about This Topic

Perioperative administration of pregabalin has been associated with decreased postoperative pain and opioid requirements

What This Article Tells Us That Is New

This secondary analysis of data demonstrating that perioperative administration of pregabalin was associated with a reduction in opioid requirements and incisional hyperalgesia suggests that these benefits may be compromised by an increased risk of developing impaired postoperative cognitive performance

Background

Pregabalin has shown opioid sparing and analgesic effects in the early postoperative period; however, perioperative effects on cognition have not been studied. A randomized, parallel group, placebo-controlled investigation in 80 donor nephrectomy patients was previously performed that evaluated the analgesic, opioid-sparing, and antihyperalgesic effects of pregabalin. This article describes a secondary exploratory analysis that tested the hypothesis that pregabalin would impair cognitive function compared to placebo.

Methods

Eighty patients scheduled for donor nephrectomy participated in this randomized, placebo-controlled study. Pregabalin (150 mg twice daily, n = 40) or placebo (n = 40) was administered on the day of surgery and the first postoperative day, in addition to a pain regimen consisting of opioids, steroids, local anesthetics, and acetaminophen. Specific cognitive tests measuring inhibition, sustained attention, psychomotor speed, visual memory, and strategy were performed at baseline, 24 h, and 3 to 5 days after surgery, using tests from the Cambridge Neuropsychological Test Automated Battery.

Results

In the spatial working memory within errors test, the number of errors increased with pregabalin compared to placebo 24 h after surgery; median (25th, 75th percentile) values were 1 (0, 6) versus 0 (0, 1; rate ratio [95% CI], 3.20 [1.55 to 6.62]; P = 0.002). Furthermore, pregabalin significantly increased the number of errors in the stop-signal task stop-go test compared with placebo; median (25th, 75th percentile) values were 3 (1, 6) versus 1 (0, 2; rate ratio, 2.14 [1.13 to 4.07]; P = 0.020). There were no significant differences between groups in the paired associated learning, reaction time, rapid visual processing, or spatial working memory strategy tests.

Conclusions

Perioperative pregabalin significantly negatively affected subdomains of executive functioning, including inhibition, and working memory compared to placebo, whereas psychomotor speed was not changed.

Inhibition and decision-processing speed are associated with performance on dynamic posturography in older adults

Changes in cognition due to age have been associated with falls and reduced standing postural control. Sensory integration is one component of postural control that may be influenced by certain aspects of cognitive functioning. This study investigated associations between measures of cognitive function and sensory integration capabilities for healthy young and older adults. Dynamic posturography was performed using the Equitest Sensory Organization Test (SOT) protocol to evaluate sensory integration during standing using sway-referencing of the platform and/or visual scene to alter somatosensory and visual inputs. The Equilibrium Score was used as a measure of sway. Cognitive testing examined aspects of cognitive function that have been associated with falls in older adults. A correlational analysis investigated associations between the cognitive measures and postural sway during the altered sensory conditions of the SOT. For older subjects only, slower decision-processing speed was associated with increased sway during SOT conditions whenever somatosensation was altered. Reduced perceptual inhibition was associated with increased sway whenever somatosensation was intact, and particularly when vision was altered in the presence of somatosensation. Visuospatial construct ability was associated with sway only when the eyes were closed during altered somatosensation. Task-switching was associated with sway only when vision and somatosensation were intact. With increased age, deficits in decision speed and inhibition appear associated with the sensory integration crucial for balance maintenance. Associations are modulated by the availability of somatosensation and vision. These associations define situations and individual differences in aspects of cognition that may relate to situational loss of balance in older adults.

Cognitive Rehabilitation in Bilateral Vestibular Patients: A Computational Perspective

There is evidence that vestibular sensory processing affects, and is affected by, higher cognitive processes. This is highly relevant from a clinical perspective, where there is evidence for cognitive impairments in patients with peripheral vestibular deficits. The vestibular system performs complex probabilistic computations, and we claim that understanding these is important for investigating interactions between vestibular processing and cognition. Furthermore, this will aid our understanding of patients’ self-motion perception and will provide useful information for clinical interventions. We propose that cognitive training is a promising way to alleviate the debilitating symptoms of patients with complete bilateral vestibular loss (BVP), who often fail to show improvement when relying solely on conventional treatment methods. We present a probabilistic model capable of processing vestibular sensory data during both passive and active self-motion. Crucially, in our model, knowledge from multiple sources, including higher-level cognition, can be used to predict head motion. This is the entry point for cognitive interventions. Despite the loss of sensory input, the processing circuitry in BVP patients is still intact, and they can still perceive self-motion when the movement is self-generated. We provide computer simulations illustrating self-motion perception of BVP patients. Cognitive training may lead to more accurate and confident predictions, which result in decreased weighting of sensory input, and thus improved self-motion perception. Using our model, we show the possible impact of cognitive interventions to help vestibular rehabilitation in patients with BVP.

Falls, Cognitive Function, and Balance Profiles of Singapore Community-Dwelling Elderly Individuals: Key Risk Factors

Objective:

This study compared occurrence of falls, cognitive function, and balance profiles across participants in elderly age categories, investigating associations between the 3 aspects in a sample of Singapore’s elderly population.

Method:

Community-dwelling elderly individuals (N = 385) were randomly recruited and grouped into “young-old (65-74 years),” “medium-old (75-84 years),” and “oldest-old (above 85 years)” groups. The Fallproof Health and Activity questionnaire, adapted Mini-Mental State Examination (MMSE), and Berg Balance Scale (BBS) tests were used to survey information related to falls, cognition, and balance profiles.

Results:

Findings revealed significant differences in MMSE and BBS scores across the age groups. Participants with mild cognitive impairment (odds ratio [OR] = 1.87, 95% confidence interval [CI] = 1.08-3.25) and BBS score ≤40 (OR = 0.25, 95% CI = 0.14-0.46) were at the highest risk of falling.

Conclusion:

Community-dwelling elderly individuals with subtle cognitive impairment and BBS scores ≤40 displayed an increased risk of falling.