Gait abnormalities of COPD are not directly related to respiratory function

The effects of adding a six-month Pilates exercise program to three months of traditional community-based pulmonary rehabilitation in individuals with COPD: a prospective cohort study

Introduction

Pilates exercise may complement traditional pulmonary rehabilitation in individuals with chronic obstructive pulmonary disease (COPD). The objective was to analyze the effects of adding a six-month Pilates exercise program to a three-month pulmonary rehabilitation for individuals with COPD.

Methods

Thirty-five participants with COPD (GOLD B) were assigned to the intervention (n=14) or control (n=21) group. Both groups received an initial three months of a pulmonary rehabilitation program. The intervention group further underwent six months of pilates. Participants were evaluated at baseline and at three, six, and nine months. Lung function and strength of respiratory muscles were defined as primary outcomes. Secondary outcomes included cardiac, physical function, and exacerbation episodes.

Results

There were no consistent statistically significant differences between groups for the lung function outcomes (p\<0.05). Maximal inspiratory and expiratory pressure increased significantly at three months in both groups (p\<0.05). It was significantly superior in the intervention group at nine months for maximal inspiratory pressure (p=0.005) and six and nine months for maximal expiratory pressure (p=0.027 and p\<0.001, respectively). Changes in muscle strength (knee extension and handgrip) were comparable between groups (p>0.05), but exercise-induced fatigue and balance were significantly superior in the intervention group at the six- and nine-month follow-ups (p\<0.05).

Discussion

Pilates exercise programs may be implemented to augment traditional pulmonary rehabilitation with the goal of improving the strength of respiratory muscles.

Conclusion

Adding a Pilates exercise program to pulmonary rehabilitation resulted in superior strength of respiratory muscles, higher resistance to exercise-induced fatigue, and improved balance.

Gait differences between COPD and healthy controls: systematic review and meta-analysis

BACKGROUND

Despite the importance of gait as a determinant of falls, disability and mortality in older people, understanding of gait impairment in COPD is limited. This study aimed to identify differences in gait characteristics during supervised walking tests between people with COPD and healthy controls.

METHODS

We searched 11 electronic databases, supplemented by Google Scholar searches and manual collation of references, in November 2019 and updated the search in July 2021. Record screening and information extraction were performed independently by one reviewer and checked for accuracy by a second. Meta-analyses were performed in studies not considered at a high risk of bias.

RESULTS

Searches yielded 21 085 unique records, of which 25 were included in the systematic review (including 1015 people with COPD and 2229 healthy controls). Gait speed was assessed in 17 studies (usual speed: 12; fast speed: three; both speeds: two), step length in nine, step duration in seven, cadence in six, and step width in five. Five studies were considered at a high risk of bias. Low-quality evidence indicated that people with COPD walk more slowly than healthy controls at their usual speed (mean difference (MD) -19 cm·s-1, 95% CI -28 to -11 cm·s-1) and at a fast speed (MD -30 cm·s-1, 95% CI -47 to -13 cm·s-1). Alterations in other gait characteristics were not statistically significant.

CONCLUSION

Low-quality evidence shows that people with COPD walk more slowly than healthy controls, which could contribute to an increased falls risk. The evidence for alterations in spatial and temporal components of gait was inconclusive. Gait impairment appears to be an important but understudied area in COPD.

Measurement properties of device-based physical activity instruments in ambulatory adults with physical disabilities and/or chronic diseases: a scoping review

BACKGROUND

People with physical disabilities and/or chronic diseases tend to have an inactive lifestyle. Monitoring physical activity levels is important to provide insight on how much and what types of activities people with physical disabilities and/or chronic diseases engage in. This information can be used as input for interventions to promote a physically active lifestyle. Therefore, valid and reliable physical activity measurement instruments are needed. This scoping review aims 1) to provide a critical mapping of the existing literature and 2) directions for future research on measurement properties of device-based instruments assessing physical activity behavior in ambulant adults with physical disabilities and/or chronic diseases.

METHODS

Four databases (MEDLINE, CINAHL, Web of Science, Embase) were systematically searched from 2015 to April 16th 2023 for articles investigating measurement properties of device-based instruments assessing physical activity in ambulatory adults with physical disabilities and/or chronic diseases. For the majority, screening and selection of eligible studies were done in duplicate. Extracted data were publication data, study data, study population, device, studied measurement properties and study outcome. Data were synthesized per device.

RESULTS

One hundred three of 21566 Studies were included. 55 Consumer-grade and 23 research-grade devices were studied on measurement properties, using 14 different physical activity outcomes, in 23 different physical disabilities and/or chronic diseases. ActiGraph (n = 28) and Fitbit (n = 39) devices were most frequently studied. Steps (n = 68) was the most common used physical activity outcome. 97 studies determined validity, 11 studies reliability and 6 studies responsiveness.

CONCLUSION

This scoping review shows a large variability in research on measurement properties of device-based instruments in ambulatory adults with physical disabilities and/or chronic diseases. The variability highlights a need for standardization of and consensus on research in this field. The review provides directions for future research.

Laboratory and free-living gait performance in adults with COPD and healthy controls

Background

Gait characteristics are important risk factors for falls, hospitalisations and mortality in older adults, but the impact of COPD on gait performance remains unclear. We aimed to identify differences in gait characteristics between adults with COPD and healthy age-matched controls during 1) laboratory tests that included complex movements and obstacles, 2) simulated daily-life activities (supervised) and 3) free-living daily-life activities (unsupervised).

Methods

This case-control study used a multi-sensor wearable system (INDIP) to obtain seven gait characteristics for each walking bout performed by adults with mild-to-severe COPD (n=17; forced expiratory volume in 1 s 57±19% predicted) and controls (n=20) during laboratory tests, and during simulated and free-living daily-life activities. Gait characteristics were compared between adults with COPD and healthy controls for all walking bouts combined, and for shorter (≤30 s) and longer (>30 s) walking bouts separately.

Results

Slower walking speed (-11 cm·s-1, 95% CI: -20 to -3) and lower cadence (-6.6 steps·min-1, 95% CI: -12.3 to -0.9) were recorded in adults with COPD compared to healthy controls during longer (>30 s) free-living walking bouts, but not during shorter (≤30 s) walking bouts in either laboratory or free-living settings. Double support duration and gait variability measures were generally comparable between the two groups.

Conclusion

Gait impairment of adults with mild-to-severe COPD mainly manifests during relatively long walking bouts (>30 s) in free-living conditions. Future research should determine the underlying mechanism(s) of this impairment to facilitate the development of interventions that can improve free-living gait performance in adults with COPD.

Effects of creative dance on functional capacity, pulmonary function, balance, and cognition in COPD patients: A randomized controlled trial

BACKGROUND

Exercise training is key to the comprehensive management of patients with chronic obstructive pulmonary disease (COPD). Creative dance can be an innovative approach as effective as traditional exercise training.

OBJECTIVES

This study aimed to investigate effect of creative dance-based exercise (CDE) training on functional capacity, postural stability and balance, pulmonary and cognitive functions, respiratory and peripheral muscle strength in COPD patients.

METHODS

Twenty-four patients with COPD were randomly allocated to either "chest physiotherapy and home-based walking program" (PT) or "CDE alongside home-based chest physiotherapy group" (PT+CDE). Both groups performed chest PT program twice a day for 5 days per week for 8 weeks. PT+CDE group received CDE training 2 days a week for 8 weeks. Primary outcome was six minute walk test (6MWT). Secondary outcomes were postural stability and balance, pulmonary function, maximum inspiratory (MIP) and expiratory (MEP) pressure, peripheral muscle strength, Montreal Cognitive Assessment (MoCA), COPD Assessment Test (CAT), and BODE index. Outcome measures were assessed at baseline and after 8 weeks of training.

RESULTS

Both groups showed statistically significant improvements in 6MWT distance, MIP, MEP, MoCA score, CAT, and BODE index (p < 0.05). Only with CDE training was achieved improvements in postural stability and balance scores, pulmonary function, and peripheral muscle strength (p < 0.05). The improvements in 6 MWT distance, MEP, MoCA score, and CAT were greater in PT+CDE group (p < 0.05).

CONCLUSION

Use of creative dance training in addition to home-based chest PT program was more effective than chest PT program regarding primary and secondary outcomes in COPD patients.

Associations Between Cognitive Function, Balance, and Gait Speed in Community-Dwelling Older Adults with COPD

BACKGROUND AND PURPOSE

Older adults with chronic obstructive pulmonary disease (COPD) are at risk for physical and cognitive impairment. Cognitive function is associated with falls in older adults. However, it is unknown whether a relationship exists between cognitive function and falls in patients with COPD. The aim of this study was to examine the relationships between cognitive function, balance, and gait speed in older adults with COPD.

PATIENTS AND METHODS

A secondary analysis was performed using data from the 2010 wave of the Health and Retirement Study (HRS). Cognitive (immediate and delayed recall, executive function) and physical (gait speed, tandem balance time) measure data were extracted for older adults with COPD (n = 382) and an age-matched control group without COPD (n = 382) who met inclusion/exclusion criteria. Multivariate linear regression modeling was performed to examine associations between cognitive function and mobility or balance while controlling for age, gender, body mass index, grip strength, and education.

RESULTS

In older adults with COPD, delayed recall was significantly associated with tandem balance performance (β= 1.42, P < .05). Other cognitive measures were not associated with gait speed or balance.

CONCLUSION

In older adults with COPD, one of four cognitive functions was associated with a static standing balance task. Screening of cognitive function, specifically delayed recall, should be a part of the management of falls in this population.

Impact of cognitive capacity on physical performance in chronic obstructive pulmonary disease patients: A scoping review

Background: Chronic obstructive pulmonary disease (COPD) is often accompanied by impaired cognitive and physical function. However, the role of cognitive function on motor control and purposeful movement is not well studied. The aim of the review was to determine the impact of cognition on physical performance in COPD. Methods: Scoping review methods were performed including searches of the databases: MEDLINE, EMBASE, Cochrane Systematic Reviews, Cochrane (CENTRAL), APA PsycINFO, and CINAHL. Two reviewers independently assessed articles for inclusion, data abstraction, and quality assessment. Results: Of 11,252 identified articles, 44 met the inclusion criteria. The review included 5743 individuals with COPD (68% male) with the forced expiratory volume in one second range of 24-69% predicted. Cognitive scores correlated with strength, balance, and hand dexterity, while 6-min walk distance (n = 9) was usually similar among COPD patients with and without cognitive impairment. In 2 reports, regression analyses showed that delayed recall and the trail making test were associated with balance and handgrip strength, respectively. Dual task studies (n = 5) reported impaired balance or gait in COPD patients compared to healthy adults. Cognitive or physical Interventions (n = 20) showed variable improvements in cognition and exercise capacity. Conclusions: Cognition in COPD appears to be more related to balance, hand, and dual task function, than exercise capacity.

Updated Perspectives on the Role of Biomechanics in COPD: Considerations for the Clinician

Patients with chronic obstructive pulmonary disease (COPD) demonstrate extra-pulmonary functional decline such as an increased prevalence of falls. Biomechanics offers insight into functional decline by examining mechanics of abnormal movement patterns. This review discusses biomechanics of functional outcomes, muscle mechanics, and breathing mechanics in patients with COPD as well as future directions and clinical perspectives. Patients with COPD demonstrate changes in their postural sway during quiet standing compared to controls, and these deficits are exacerbated when sensory information (eg, eyes closed) is manipulated. If standing balance is disrupted with a perturbation, patients with COPD are slower to return to baseline and their muscle activity is differential from controls. When walking, patients with COPD appear to adopt a gait pattern that may increase stability (eg, shorter and wider steps, decreased gait speed) in addition to altered gait variability. Biomechanical muscle mechanics (ie, tension, extensibility, elasticity, and irritability) alterations with COPD are not well documented, with relatively few articles investigating these properties. On the other hand, dyssynchronous motion of the abdomen and rib cage while breathing is well documented in patients with COPD. Newer biomechanical technologies have allowed for estimation of regional, compartmental, lung volumes during activity such as exercise, as well as respiratory muscle activation during breathing. Future directions of biomechanical analyses in COPD are trending toward wearable sensors, big data, and cloud computing. Each of these offers unique opportunities as well as challenges. Advanced analytics of sensor data can offer insight into the health of a system by quantifying complexity or fluctuations in patterns of movement, as healthy systems demonstrate flexibility and are thus adaptable to changing conditions. Biomechanics may offer clinical utility in prediction of 30-day readmissions, identifying disease severity, and patient monitoring. Biomechanics is complementary to other assessments, capturing what patients do, as well as their capability.

Technologies for the Instrumental Evaluation of Physical Function in Persons Affected by Chronic Obstructive Pulmonary Disease: A Systematic Review

Several systems, sensors, and devices are now available for the instrumental evaluation of physical function in persons with Chronic Obstructive Pulmonary Disease (COPD). We aimed to systematically review the literature about such technologies. The literature search was conducted in all major scientific databases, including articles published between January 2001 and April 2022. Studies reporting measures derived from the instrumental assessment of physical function in individuals with COPD were included and were divided into application and validation studies. The quality of validation studies was assessed with the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) risk of bias tool. From 8752 articles retrieved, 21 application and 4 validation studies were included in the systematic review. Most application studies employed accelerometers, gait analysis systems, instrumented mattresses, or force plates to evaluate walking. Surface electro-myography or near-infrared spectroscopy were employed in four studies. Validation studies were heterogeneous and presented a risk of bias ranging from inadequate to doubtful. A variety of data regarding physical function can be retrieved from technologies used in COPD studies. However, a general lack of standardization and limitations in study design and sample size hinder the implementation of the instrumental evaluation of function in clinical practice.

The Coronavirus Footprint on Dual-Task Performance in Post-Acute Patients after Severe COVID-19: A Future Challenge for Rehabilitation

Recent studies suggest that also the non-critical form of COVID-19 infection may be associated with executive function impairments. However, it is not clear if they result from cognitive impairments or by COVID-19 infection per se. We aimed to investigate if patients in the post-acute stage of severe COVID-19 (PwCOVID), without manifest cognitive deficits, reveal impairments in performing dual-task (DT) activities compared to healthy controls (HS). We assessed balance in 31 PwCOVID vs. 30 age-matched HS by stabilometry and the Timed Up and Go (TUG) test with/without a cognitive DT. The DT cost (DTC), TUG test time and sway oscillations were recorded; correct cognitive responses (CCR) were calculated to evaluate cognitive performance. Results show a significant difference in overall DT performance between PwCOVID and HS in both stabilometry (p < 0.01) and the TUG test (p < 0.0005), although with similar DTCs. The main difference in the DTs between groups emerged in the CCR (effect size > 0.8). Substantially, PwCOVID gave priority to the motor task, leaving out the cognitive one, while HS performed both tasks simultaneously. Our findings suggest that PwCOVID, even without a manifest cognitive impairment, may present a deficit in executive function during DTs. These results encourage the use of DTs and CCR in PwCOVID.

Impairment and characteristics of postural control sub-components in people with COPD: a scoping review

Purpose: Impairment of postural control is common in people with COPD. However, the precise characteristics of this alteration are not clearly known. The "Systems Framework for Postural Control" which define postural control sub-components, represents an interesting tool to explore this field. The main aim of this review was to identify which postural control sub-components are impaired in people with COPD and to summarise characteristics for each sub-component. A secondary aim was to precise the relation between postural control and activities of daily living (ADL).Materials and methods: A scoping review was conducted, according to the JBI methodology. Medline, Cochrane Library, Scielo, Google Scholar, OpenGrey, and HAL were searched from inception to May 2022. The search was performed in English and French.Results: Eighty-nine articles were included. There was evidence of a potential impairment for most of the postural control sub-components. Characteristics of every sub-component alteration were heterogeneous. Reduced postural control could be associated with difficulties in ADL.Conclusions: People with COPD may have impairment in a wide range of postural control sub-components. Further research is needed to clarify if a common pattern of modification exits for this alteration and to precise the link with ADL.Implications for rehabilitationImpairment of postural control is a common extra-respiratory manifestation in people with COPD and so clinicians must include it in their clinical reasoning.Numerous postural control sub-components could be altered in people with COPD, suggesting that postural control assessment must be holistic.This scoping review shows that characteristics of postural control impairment are varied and that there may be no common pattern at the COPD population level.The relationship between impaired postural control and activities of daily living remains unclear, but clinicians should be alert to potential negative interactions between these two areas.

Impaired Balance and Gait Characteristics in Patients With Chronic Heart Failure

BACKGROUND AND AIMS

Heart failure affects most systems of the body and causes various problems in patients. Balance deficits and gait deviations can be a result of these effects. There is little information in the literature about balance and gait parameters in chronic heart failure (CHF). This study aimed to investigate balance abnormalities together with gait deficits for possible associations in patients with CHF and compare them to healthy controls.

METHODS

Twenty-two (22) patients with CHF (59±2.5 years) and 22 age- and gender-matched healthy subjects (59.4±6.8 years) participated in the study. This study is a cross-sectional/comparison study. Balance was evaluated using the Activity-Specific Balance Confidence Scale (ABC) and the Mini-Balance Evaluation Systems Test (Mini-BESTest) balance battery, which includes the timed up-and-go test (TUG) and dual-task TUG. Gait analysis was performed using a Biodex Gait Trainer. Peripheral muscle strength (quadriceps muscle and handgrip strength) was assessed using a hand dynamometer and exercise capacity using the six-minute walk test (6MWT).

RESULTS

The CHF patients had significantly lower Mini-BESTest total, reactive postural control, and gait stability scores, significantly longer TUG/dual-task TUG time, and lower ABC score compared to the healthy control group (p<0.05). Chronic heart failure patients also showed significantly lower gait speed, stride length, gait cycle and step length (p<0.05). Dominant-side quadriceps muscle and handgrip strength and 6MWT distance were significantly reduced in CHF (p<0.05). Anticipatory postural adjustments and sensory orientation did not differ between groups.

CONCLUSIONS

Our study demonstrated impaired balance and gait performance and reduced muscle strength and exercise capacity in patients with CHF. Cardiac rehabilitation including balance and walking training should be planned for CHF patients to eliminate balance disorders, gait impairment and prevent falls in this patient group.

Balance performance in patients with post-acute COVID-19 compared to patients with an acute exacerbation of chronic obstructive pulmonary disease and healthy subjects

COVID-19 leaves important sequelae in patients, not only in those who had the experience of a critical illness but also in patients with severe form. Understanding the impairments allows us to target rehabilitation to patients' real needs; balance impairments are an assumed sequela of COVID-19, but no study has specifically evaluated balance performance in these patients. Their performance was compared to that of patients with a pulmonary disease that leads to systemic diseases, such as patients with an acute exacerbation of chronic obstructive pulmonary disease (PwAECOPD), and of healthy subjects. A total of 75 subjects were assessed: 25 patients with COVID-19 (PwCOVID) with a severe form in the acute phase, 25 PwAECOPD and 25 healthy subjects sex- and age-matched. A stabilometric platform was used to evaluate static balance, both with eyes open and closed, while the dynamic balance was assessed with the Mini-BESTest and the Timed Up and Go test. When compared to healthy subjects, results showed that PwCOVID had worse performance in both static (P < 0.005) and dynamic (P < 0.0001) balance, with a large effect size in all measures (>0.8). Moreover, PwCOVID showed similar results to those of PwAECOPD. In conclusion, PwCOVID showed a balance deficit in both dynamic and static conditions. Therefore, as for PwAECOPD, they should require not only respiratory rehabilitation but also balance and mobility physiotherapy to prevent today's PwCOVID from becoming tomorrow's fallers.

Patients Surviving Critical COVID-19 have Impairments in Dual-task Performance Related to Post-intensive Care Syndrome

Objective

The purpose was to examine Dual Task (DT) performance in patients surviving severe and critical COVID-19 compared to patients with chronic lung disease (CLD). Secondarily, we aimed to determine the psychometric properties of the Timed Up and Go (TUG) test in patients surviving COVID-19.

Design

Prospective, cross-sectional, observational study.

Setting

Academic medical center within United States.

Patients

Ninety-two patients including 36 survivors of critical COVID-19 that required mechanical ventilation (critical-COVID), 20 patients recovering from COVID-19 that required supplemental oxygen with hospitalization (severe-COVID), and 36 patients with CLD serving as a control group.

Measurements and Main Results

Patients completed the TUG, DT-TUG, Short Physical Performance Battery (SPPB), and Six Minute Walk Test (6MWT) 1-month after hospital discharge. A subset of patients returned at 3-months and repeated testing to determine the minimal detectable change (MDC). Critical-COVID group (16.8 ± 7.3) performed the DT-TUG in significantly slower than CLD group (13.9 ± 4.8 s; P = .024) and Severe-COVID group (13.1 ± 5.1 s; P = .025). Within-subject difference between TUG and DT-TUG was also significantly worse in critical-COVID group (−21%) compared to CLD (−10%; P = .012), even despite CLD patients having a higher comorbid burden (P < .003) and older age (P < .001). TUG and DT-TUG demonstrated strong to excellent construct validity to the chair rise test, gait speed, and 6MWT for both COVID-19 groups (r = −0.84to 0.73, P < .05). One- and 3-months after hospital discharge there was a floor effect of 14% (n = 5/36) and 5.2% (n = 1/19), respectively for patients in the critical-COVID group. Ceiling effects were noted in four (11%) critical-COVID, six (30%) severe-COVID patients for the TUG and DT-TUG at 1-month.

Conclusion

The ability to maintain mobility performance in the presence of a cognitive DT is grossly impaired in patients surviving critical COVID-19. DT performance may subserve the understanding of impairments related to Post-intensive care syndrome (PICS) for survivors of critical illness.

A pilot study on the feasibility and effectiveness of treadmill-based perturbations for assessing and improving walking stability in chronic obstructive pulmonary disease

BACKGROUND

Falls risk is elevated in chronic obstructive pulmonary disease (COPD). However, there is a lack of evidence regarding the contributing factors. Here, we examined the feasibility of, and initial responses to, large walking perturbations in COPD, as well as the adaptation potential of people with COPD to repeated walking perturbations that might indicate potential for perturbation-based balance training in COPD.

METHODS

12 participants with COPD undergoing inpatient pulmonary rehabilitation and 12 age-gender-matched healthy control participants walked on an instrumented treadmill and experienced repeated treadmill-belt acceleration perturbations (leading to a forward balance loss). Three-dimensional motion capture was used to quantify the stability of participants body position during perturbed walking. Feasibility, stability following the initial perturbations and adaptation to repeated perturbations were assessed.

FINDINGS

Using perturbations in this manner was feasible in this population (no harness assists and participants completed the minimum number of perturbations). No clear, specific deficit in reactive walking stability in COPD was found (no significant effects of participant group on stability or recovery step outcomes). There were mixed results for the adaptability outcomes which overall indicated some adaptability to repeated perturbations, but not to the same extent as the healthy control participants.

INTERPRETATION

Treadmill-based perturbations during walking are feasible in COPD. COPD does not appear to result in significant deficits in stability following sudden perturbations and patients do demonstrate some adaptability to repeated perturbations. Perturbation-based balance training may be considered for fall prevention in research and practice in people with COPD.

Responsiveness and Minimal Clinically Important Difference of the Brief-BESTest in People With COPD After Pulmonary Rehabilitation

OBJECTIVE

he Brief-Balance Evaluation Systems Test (Brief-BESTest) is a comprehensive, reliable, and valid balance test that provides valuable information to guide balance training in people with chronic obstructive pulmonary disease (COPD). Its clinical interpretability is, however, currently limited, because cutoff points to identify clinically relevant changes in people with COPD after pulmonary rehabilitation are still lacking. This study aimed to establish the responsiveness and minimal clinically important difference (MCID) for the Brief-BESTest in people with COPD after pulmonary rehabilitation (PR).

METHODS

A secondary analysis of data from 2 previous studies was conducted. The modified British Medical Research Council (mMRC) dyspnea scale, the 6-Minute Walk Test (6-MWT), and the Brief-BESTest (0-24 points) were collected in people with COPD pre/post a 12-week PR program including balance training. The MCID was computed using anchor- and distribution-based methods. Changes in the 6-MWT and the mMRC were assessed and used as anchors. The pooled MCID was computed using the arithmetic weighted mean (2/3 anchor- and 1/3 distribution-based methods).

RESULTS

Seventy-one people with COPD (69 years [SD = 8]; 76% male; FEV1 = 49.8%predicted [SD = 18%]) were included. There was a significant improvement in the Brief-BESTest after PR (mean difference = 3 points [SD = 3]). Significant correlations were found between the Brief-BESTest and the mMRC (r = -.31) and the 6-MWT (r = .37). The pooled MCID was 3.3 points.

CONCLUSION

An improvement of at least 3 points in the Brief-BESTest in people with COPD will enhance the interpretability of PR effects on balance performance of this population and guide tailored interventions.

IMPACT

The Brief-BESTest outcome measure is comprehensive, easily administered, and simple to interpret in clinical practice. This study represents a significant contribution toward the clinical interpretation of changes in balance in people with COPD following PR.

Determinants of gait speed in patients with heart failure with reduced ejection fraction

OBJECTIVE

Given the prognostic significance of gait speed, there is insufficient evidence about possible functional determinants of gait speed in patients with heart failure with reduced ejection fraction (HFrEF). Therefore, the objective of this study was to investigate the functional determinants of gait speed in patients with HFrEF.

METHODS

Fifty-nine patients with HFrEF participated in this cross-sectional study. Demographic and clinical characteristics were recorded. The gait speed was determined with a 4-meter walking test. Dyspnea perception was assessed with the modified medical research council (mMRC) scale. Functional capacity was evaluated with a 6-minute walk test (6MWT). The five times sit-to-stand (5-STS) test and the Berg Balance Scale (BBS) were used to measure functional mobility and balance. Physical activity was evaluated with the International Physical Activity Questionnaire (IPAQ) Short-Form.

RESULTS

Gait speed was correlated with age (r=-0.368, p=0.004), NYHA functional class (r=-0.438, p=0.001), mMRC score (r=-0.422, p=0.001), 6MWT (r=0.650, p<0.001), 5STS (r=-0.506, p<0.001), BBS (r=0.586, p<0.001), IPAQ (r=0.305, p=0.019) and IPAQ-Sitting time (r=-0.327, p=0.011). On multiple linear regression analysis, the 6MWT distance and BBS were independent determinants of the usual gait speed in patients with HFrEF, accounting for 44.4% of the variance.

CONCLUSION

This study indicates that functional capacity and balance are independent functional determinants of gait speed in patients with HFrEF.

Gait speed is associated with death or readmission among patients surviving acute hypercapnic respiratory failure

Objectives

Death or hospital readmission are frequent among patients surviving acute hypercapnic respiratory failure (AHRF). Severity scores are not valid to predict death or readmission after AHRF. Gait speed, a simple functional parameter, has been associated with hospital admission and death in the general population. The purpose of this study is to highlight an association between gait speed at hospital discharge and death or readmission among AHRF survivors.

Design

Secondary analysis of a prospective cohort study.

Settings

Single Swiss tertiary hospital, pulmonary division.

Participants

Patients were prospectively recruited to form a cohort of patients surviving AHRF in the intensive care unit between January 2012 and May 2015.

Outcome measure

Gait speed was derived from a 6 min walking test (6MWT) before hospital discharge. All predictive variables were prospectively collected. Death or hospital readmission were recorded for 6 months. Univariate and multivariate analyses were performed to evaluate the association between predictive variables and death or hospital readmission.

Results

71 patients performed a 6MWT. 34/71 (48%) patients died or were readmitted to the hospital during the observation period. Median gait speed was 0.7 (IQR 0.3–1.0) m/s. At 6 months, 66% (25/38) of slow walkers (gait speed <0.7 m/s) and 27% (9/33) of non-slow walkers died or were readmitted to the hospital (p=0.002). In univariate analysis, gait speed was associated with death or readmission (HR 0.41; 95% CI 0.19 to 0.90, p=0.025). In a multivariate model adjusted for age, gender, body mass index, forced expired volume, heart failure and home mechanical ventilation, gait speed remained the only variable associated with death or readmission (multivariate HR: 0.35; 95% CI 0.14 to 0.88, p=0.025).

Conclusion

This study suggests that a simple functional parameter such as gait speed is associated with death or hospital readmission in patients surviving AHRF.

Trial registration number

NCT02111876.

The influence of cognitive load on static balance in chronic obstructive pulmonary disease patients

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) may demonstrate cognitive function and balance deterioration. These two phenomena are often realized simultaneously during daily living activities, where the risk of falling may be increased due to possible postural disturbance when focusing on a cognitive task during motion. Despite the high rate of falls in COPD, there is currently a lack of affordable clinical instruments to quantify the interaction between cognitive tasks and static balance in these patients. Therefore, this study aims to assess the balance perturbation induced by cognitive tasks using a new cost-effective protocol which can easily be implemented in clinical settings.

METHOD

A total of 21 COPD patients (Age: 64 ± 8 yrs, Forced Expiratory Volume in one second = 41 ± 17%, Women: 7) and 21 matched healthy controls participated in the study. They performed two cognitive tasks (counting backward by 3s and naming animals) with eyes open and with eyes closed. Each trial lasted 60 s, with balance-related parameters recorded and quantified using a Wii Balance Board. A three-way ANOVA (cognitive task, eyes action, and health status) for balance-related parameters derived from the center of pressure displacement was performed.

RESULTS

COPD, vision, and cognitive tasks altered the balance; no interaction between conditions was observed. There was no correlation between cognitive ability, respiratory function, and the balance-related parameters.

CONCLUSION

Compared to healthy controls, the COPD patients had impaired balance. Cognitive tasks altered postural control in both COPD and controls, where this alteration was more pronounced with eyes closed.

Cognitive and motor performances in dual task in patients with chronic obstructive pulmonary disease: a comparative study

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) may display a motor and/or cognitive disadvantage during dual tasking. However, studies investigating dual task are quite limited in patients with COPD.

AIMS

To compare cognitive and motor performances (i.e., muscle force production and functional balance/mobility together with a cognitive task) in dual task between patients with COPD and healthy controls.

METHODS

Thirty-five clinically stable patients with COPD and 27 age- and sex-matched healthy controls participated in this cross-sectional controlled study. The muscle force production (knee extension muscle strength assessed with an isokinetic strength dynamometer) and functional balance/mobility (Timed Up and Go (TUG) test) were performed with and without a cognitive task. Dual-task interference (DTI) was assessed. Additionally, the rate of correct responses per second (RCR) was calculated to evaluate cognitive performance.

RESULTS

The decrease in RCR_{muscle force production} values was greater in the COPD group compared with the control group (p = 0.045). Similarly, the cognitive DTI in muscle force production test was higher in the control group than in the COPD group (p < 0.001). There was no significant difference in other outcome measures between the two groups (p > 0.05).

CONCLUSION

The study results indicate that in individuals with COPD, cognitive performance deteriorations are more pronounced than motor performance defects during dual tasking. Further studies are needed to investigate the effects of dual task taking into account this disadvantage in patients with COPD rather than focusing solely on motor performance.

Balance assessment in people with COPD: An evidence-based guide

Balance problems and an increased rate and risk of falls are common in people with chronic obstructive pulmonary disease (COPD). Although a balance assessment is now recommended by clinical practice guidelines for pulmonary rehabilitation, specific tests have yet to be suggested. The purpose of this review is to provide an evidence-based synthesis of balance measurement in older adults and in people with COPD, to guide practice in this area. An overview of best practices for assessing balance and fall risk in older adults is provided along with a practical synthesis of evidence to date on common balance measures used in people with COPD such as the Timed Up and Go, Single Leg Stance, Berg Balance, and Mini and Full Balance Evaluation Systems Tests. Finally, two clinical scenarios are described to illustrate the process of evidence-based clinical decision-making with respect to balance assessment in people with COPD. Ultimately, the selection of balance test and its interpretation will depend on the purpose of the assessment, available data on psychometric properties, the patient’s individual characteristics, and the resources available to the clinician.

Balance impairment in individuals with COPD: a systematic review with meta-analysis

BACKGROUND

People with chronic obstructive pulmonary disease (COPD) are four times more likely to fall than healthy peers, leading to increased morbidity and mortality. Poor balance is a major risk factor for falls. This review aims to quantify the extent of balance impairment in COPD, and establish contributing clinical factors, which at present are sparse.

METHODS

Five electronic databases were searched, in July 2017 and updated searches were performed in March 2019, for studies comparing balance in COPD with healthy controls. Meta-analyses were conducted on sample mean differences (MD) and reported correlations between balance and clinical factors. Meta-regression was used to quantify the association between mean difference in percentage predicted forced expiratory volume in 1 s (FEV₁) and mean balance impairment. Narrative summaries were provided where data were insufficient for meta-analysis.

RESULTS

Twenty-three studies were included (n=2751). Meta-analysis indicated COPD patients performed worse than healthy controls on timed up and go (MD=2.77 s, 95% CI 1.46 s to 4.089 s, p=<0.005), single leg stance (MD=-11.75 s, 95% CI -15.12 s to -8.38 s, p=<0.005) and berg balance scale (MD=-6.66, 95% CI -8.95 to -4.37, p=<0.005). The pooled correlation coefficient between balance and reduced quadriceps strength was weak-moderate (r=0.37, 95% CI 0.23 to 0.45, p=<0.005). The relationship between differences in percentage predicted FEV₁ and balance were negligible (r² =<0.04).

CONCLUSIONS

Compared with healthy controls, people with COPD have a clinically meaningful balance reduction, which may be related to reduced muscle strength, physical activity and exercise capacity. Our findings support a need to expand the focus of pulmonary rehabilitation to include balance assessment and training, and further exploration of balance impairment in COPD. PROSPERO registration number CRD4201769041.

Chronic Obstructive Pulmonary Disease: Proprioception Exercises as an Addition to the Rehabilitation Process

Respiratory rehabilitation in patients with chronic obstructive pulmonary disease (COPD) is recognized as a cornerstone for the therapeutic path. Physiotherapy involves physical activity with aerobic and anaerobic exercises, which can improve the patient's symptomatic picture, such as motor function, emotional status (depression and anxiety), and improve the pain perception. The training of proprioception is not included in the structure of the exercises proposed by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). The training of proprioception is a very useful strategy for stimulating the cerebellum, a neurological suffering area in patients with COPD. The cerebellum sorts information about pain and emotions, as well as motor stimuli. The article discusses the need to introduce proprioception in respiratory rehabilitation protocols, highlighting the neurological relationships with the management of comorbidities.

Is the Brief-BESTest Brief Enough? Suggested Modifications Based on Structural Validity and Internal Consistency

BACKGROUND

The Brief Balance Evaluation Systems Test (Brief-BESTest) could be a useful tool for balance assessment. Although some psychometric characteristics have been examined, others still need to be clarified.

OBJECTIVE

The objective was to assess the structural validity, convergent validity, discriminant validity, and internal consistency of the Brief-BESTest in neurological patients.

DESIGN

This was a cross-sectional study.

METHODS

Data were from 416 patients with neurological disease and related balance disorders. Patients were assessed with the 5-levels Activities-Specific Balance Confidence Scale (ABC 5-levels), Brief-BESTest, and some simple balance tests (ie, 1-leg stance, Timed "Up & Go" test, functional reach, and a fall history questionnaire). Three Brief-BESTest models were examined through confirmatory factor analysis, and the following indexes were calculated: Comparative Fit Index, Tucker-Lewis Index, and root-mean-square error of approximation. Convergent validity was assessed by calculating the correlation between Brief-BESTest and ABC 5-levels total scores. Receiver operating characteristics assessed the ability of each model to differentiate between people with falls and those without falls. Internal consistency was measured with Cronbach α and coefficient ω.

RESULTS

Confirmatory factor analysis showed model 3 (Comparative Fit Index = 0.97; Tucker-Lewis Index = 0.95; root-mean-square error of approximation = 0.05), with item 1 removed and error covariance between items 3 and 4 and between items 5 and 6, to have a significantly better structure than models 1 and 2. The correlation between Brief-BESTest and ABC 5-levels was 0.61 (Spearman ρ) for all 3 models. The area under the curve of the receiver operating characteristics showed an acceptable accuracy (0.72) in distinguishing patients with a history of falls from those without a history of falls (95% confidence interval = 0.66-0.78) for all models and was superior to the areas under the curve of other simple balance tests (1-leg stance, Timed "Up & Go" test, functional reach). Cronbach α was good for Brief-BESTest models 1 (0.92) and 3 (0.92), but ω was greater than 0.80 only for model 3.

LIMITATIONS

The sample was heterogeneous.

CONCLUSIONS

The Brief-BESTest, after some changes, shows good validity and internal consistency in patients affected by different balance disorders.

Gait characteristics and their associations with clinical outcomes in patients with chronic obstructive pulmonary disease

BACKGROUND

Abnormalities of spatiotemporal gait parameters are frequently observed in chronic obstructive pulmonary disease (COPD). However, associations of gait parameters with clinical outcomes and their implementation into clinical practice have not been established.

RESEARCH QUESTION

To investigate gait abnormalities and their association with clinical outcomes of COPD.

METHODS

This study included 34 male outpatients with COPD and 16 community-dwelling healthy men aged ≥65 years. The subjects underwent a ten-metre walk test wearing an accelerometer. Data on gait speed, step length, cadence, walk ratio, acceleration magnitude, and standard deviation of step time (step time SD) were collected. Forced expiratory volume in 1-second, modified Medical Research Council dyspnoea score, six-minute walk distance (6MWD), quadriceps muscle strength (QMVC), and physical activity (daily steps and time spent in moderate to vigorous physical activity per day) were measured in the COPD group as clinical outcomes of COPD. We tested group differences in gait parameters, associations between gait parameters and COPD clinical outcomes, and predictive capability of gait parameters for reductions in 6MWD, QMVC, and daily steps in COPD.

RESULTS

All gait parameters except walk ratio deteriorated in COPD. Step time SD and gait speed were significant independent predictors of 6MWD in COPD (B=-0.440, p = 0.001, B = 0.339, p = 0.007, respectively). Step length was a significant independent predictor of QMVC (B=-0.609, p < 0.001) and daily steps (B=-0.453, p = 0.006). Step length was a significant predictor of muscle weakness and physical inactivity, and step time SD was significant in predicting poor 6MWD in COPD.

SIGNIFICANCE

Significant associations between gait abnormalities measured by an accelerometer and deficits in extra-pulmonary features of COPD were observed. An accelerometer-based gait analysis could be an alternative approach to assessing gait abnormalities and screening of functional decline in COPD.

Impact of Chronic Obstructive Pulmonary Disease on Cognitive and Motor Performances in Dual-Task Walking

When two tasks are performed simultaneously, they compete for attentional resources, resulting in a performance decrement in one or both tasks. Patients with attention disorders have a reduced ability to perform several tasks simultaneously (e.g., talking while walking), which increases the fall risk and frailty. This study assessed the cognitive and motor performances of patients with COPD and healthy controls within a dual-task walking paradigm. A subobjective was to assess the impact of a pulmonary rehabilitation program on the dual-task performances in COPD. Twenty-five patients with COPD and 20 controls performed a cognitive task (subtraction) and a 15-m walking test separately (single-task; ST) and jointly (dual-task; DT). In addition, a subsample of 10 patients performed the same evaluations 5 weeks later after a pulmonary rehabilitation program following current recommendations. Cognitive and gait performances in ST showed no differences between patients with COPD and controls (all p > 0.05). However, COPD patients exhibited a greater increase in gait variability than controls in DT (4.07 ± 1.46% vs. 2.17 ± 0.7%, p < 0.001). The pulmonary rehabilitation program had no effect on the dual-task impairment for the subsample of patients (p = 0.87). This study provides evidence of insufficient attentional resources to successfully deal with DT in patients with COPD, and this was expressed through an exaggerated increase in gait variability in DT walking. Given the high risk of falls and disability associated with altered gait variability, dual-task training interventions should be considered in pulmonary rehabilitation programs.

Abnormal gait pattern emerges during curved trajectories in high-functioning Parkinsonian patients walking in line at normal speed

Background

Several patients with Parkinson´s disease (PD) can walk normally along straight trajectories, and impairment in their stride length and cadence may not be easily discernible. Do obvious abnormalities occur in these high-functioning patients when more challenging trajectories are travelled, such as circular paths, which normally implicate a graded modulation in the duration of the interlimb gait cycle phases?

Methods

We compared a cohort of well-treated mildly to moderately affected PD patients to a group of age-matched healthy subjects (HS), by deliberately including HS spontaneously walking at the same speed of the patients with PD. All participants performed, in random order: linear and circular walking (clockwise and counter-clockwise) at self-selected speed. By means of pressure-sensitive insoles, we recorded walking speed, cadence, duration of single support, double support, swing phase, and stride time. Stride length-cadence relationships were built for linear and curved walking. Stride-to-stride variability of temporal gait parameters was also estimated.

Results

Walking speed, cadence or stride length were not different between PD and HS during linear walking. Speed, cadence and stride length diminished during curved walking in both groups, stride length more in PD than HS. In PD compared to HS, the stride length-cadence relationship was altered during curved walking. Duration of the double-support phase was also increased during curved walking, as was variability of the single support, swing phase and double support phase.

Conclusion

The spatio-temporal gait pattern and variability are significantly modified in well-treated, high-functioning patients with PD walking along circular trajectories, even when they exhibit no changes in speed in straight-line walking. The increased variability of the gait phases during curved walking is an identifying characteristic of PD. We discuss our findings in term of interplay between control of balance and of locomotor progression: the former is challenged by curved trajectories even in high-functioning patients, while the latter may not be critically affected.

Instrumental or Physical-Exercise Rehabilitation of Balance Improves Both Balance and Gait in Parkinson's Disease

We hypothesised that rehabilitation specifically addressing balance in Parkinson's disease patients might improve not only balance but locomotion as well. Two balance-training protocols (standing on a moving platform and traditional balance exercises) were assessed by assigning patients to two groups (Platform, n = 15, and Exercises, n = 17). The platform moved periodically in the anteroposterior, laterolateral, and oblique direction, with and without vision in different trials. Balance exercises were based on the Otago Exercise Program. Both platform and exercise sessions were administered from easy to difficult. Outcome measures were (a) balancing behaviour, assessed by both Index of Stability (IS) on platform and Mini-BESTest, and (b) gait, assessed by both baropodometry and Timed Up and Go (TUG) test. Falls Efficacy Scale-International (FES-I) and Parkinson's Disease Questionnaire (PDQ-8) were administered. Both groups exhibited better balance control, as assessed both by IS and by Mini-BESTest. Gait speed at baropodometry also improved in both groups, while TUG was less sensitive to improvement. Scores of FES-I and PDQ-8 showed a marginal improvement. A four-week treatment featuring no gait training but focused on challenging balance tasks produces considerable gait enhancement in mildly to moderately affected patients. Walking problems in PD depend on postural instability and are successfully relieved by appropriate balance rehabilitation. This trial is registered with ClinicalTrials.gov NCT03314597.

Haptic Cues for Balance: Use of a Cane Provides Immediate Body Stabilization

Haptic cues are important for balance. Knowledge of the temporal features of their effect may be crucial for the design of neural prostheses. Touching a stable surface with a fingertip reduces body sway in standing subjects eyes closed (EC), and removal of haptic cue reinstates a large sway pattern. Changes in sway occur rapidly on changing haptic conditions. Here, we describe the effects and time-course of stabilization produced by a haptic cue derived from a walking cane. We intended to confirm that cane use reduces body sway, to evaluate the effect of vision on stabilization by a cane, and to estimate the delay of the changes in body sway after addition and withdrawal of haptic input. Seventeen healthy young subjects stood in tandem position on a force platform, with eyes closed or open (EO). They gently lowered the cane onto and lifted it from a second force platform. Sixty trials per direction of haptic shift (Touch → NoTouch, T-NT; NoTouch → Touch, NT-T) and visual condition (EC-EO) were acquired. Traces of Center of foot Pressure (CoP) and the force exerted by cane were filtered, rectified, and averaged. The position in space of a reflective marker positioned on the cane tip was also acquired by an optoelectronic device. Cross-correlation (CC) analysis was performed between traces of cane tip and CoP displacement. Latencies of changes in CoP oscillation in the frontal plane EC following the T-NT and NT-T haptic shift were statistically estimated. The CoP oscillations were larger in EC than EO under both T and NT (p < 0.001) and larger during NT than T conditions (p < 0.001). Haptic-induced effect under EC (Romberg quotient NT/T ~ 1.2) was less effective than that of vision under NT condition (EC/EO ~ 1.5) (p < 0.001). With EO cane had little effect. Cane displacement lagged CoP displacement under both EC and EO. Latencies to changes in CoP oscillations were longer after addition (NT-T, about 1.6 s) than withdrawal (T-NT, about 0.9 s) of haptic input (p < 0.001). These latencies were similar to those occurring on fingertip touch, as previously shown. Overall, data speak in favor of substantial equivalence of the haptic information derived from both “direct” fingertip contact and “indirect” contact with the floor mediated by the cane. Cane, finger and visual inputs would be similarly integrated in the same neural centers for balance control. Haptic input from a walking aid and its processing time should be considered when designing prostheses for locomotion.