Balance impairment in patients with COPD

Exploring Balance Impairment and Determinants in Chronic Obstructive Pulmonary Disease: A Comparative Study with Healthy Subjects

Background: Many pulmonary and extrapulmonary factors may impair balance in patients with chronic obstructive pulmonary disease (COPD), but the determinants of this impairment are still debated. The primary aim was to compare both balance-related and independent variables that may affect balance with healthy subjects. The secondary aim was to investigate the potential determinants of balance in patients with COPD. Methods: This comparative study recruited 23 patients with COPD and 23 age- and comorbidity-matched healthy subjects. Participants were assessed regarding demographic and clinical data, "Postural Stability Test" (PST), "Limits of Stability Test" (LOST), "Clinical Test of Sensory Integration of Balance" (CTSIB), pulmonary function, respiratory and peripheral muscle strength, functional capacity, and cognitive function. Results: There were significant differences in all outcome measures assessing balance, pulmonary function, respiratory muscle strength, peripheral muscle strength, and functional capacity, but not cognitive function, in the COPD group compared to the healthy group (p < 0.05). The PST had a significant and strong correlation with maximal inspiratory pressure (MIP) (r = -0.630, p = 0.001) and a significant and moderate correlation with m. quadriceps strength and 6 min walk test (6MWT) distance (r = -0.472, p = 0.023; r = -0.496, p = 0.016; respectively). MIP, m. quadriceps strength, and 6MWT distance were independent predictors to explain the PST with an R2 = 0.336 (p = 0.004). Conclusions: The present study revealed that balance is impaired in adults with COPD, even if compared with age- and comorbidity-matched healthy subjects. Assessing and improving balance and its determinants, inspiratory and peripheral muscle strength, and functional capacity may be important for fall prevention and disease management in patients with COPD.

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.

Effects of body awareness therapy on balance and fear of falling in patients with chronic obstructive pulmonary disease: a randomized controlled trial

BACKGROUND

Assessment of extrapulmonary comorbidities is essential in chronic obstructive pulmonary disease (COPD). Deterioration of balance and increasing fear of falling are two of the most significant extrapulmonary manifestations. Although pulmonary rehabilitation (PR) is well-known and effective for COPD patients, there is a need for alternative treatments to enhance balance and alleviate concerns about falling. This study aimed to investigate the effect of Body Awareness Therapy (BAT), in addition to the PR program, on balance and fear of falling in patients with COPD.

METHODS

Forty-three patients were randomized into two groups: the BAT + PR group (BAT: once a week, 60 min + PR: 30 min, seven days of the week) or the PR group (PR: 30 min, seven days of the week) for eight weeks. Primary (balance, fear of falling) and secondary (dyspnea, muscle strength, functional capacity) outcomes were assessed at two different times: the baseline and end of the eight weeks.

RESULTS

Significant improvements were found in dynamic balance (reaction time η2 = 0.777, movement velocity η2 = 0.789, endpoint excursion η2 = 0.687, maximal excursion η2 = 0.887), static balance on firm ground (eyes opened η2 = 0.679, eyes closed η2 = 0.705), dyspnea (η2 = 0.546), muscle strength (η2 = 0.803), and functional capacity (η2 = 0.859) of the BAT + PR group (p < 0.05 for all). The improvement in fear of falling was significantly greater in the BAT + PR group than in the PR group (p < 0.001, η2 = 0.331).

CONCLUSION

The BAT method added to PR was more effective than PR alone in improving balance and reducing the fear of falling in COPD patients.

TRIAL REGISTRATION

This randomized controlled study was registered at clinicaltrials.gov, NCT04212676 , Registered 28 December 2019.

Association between self-reported falling risk and risk of hospitalization for patients with chronic obstructive pulmonary disease

RATIONALE

The association between self-report falling risk in persons with COPD and hospitalization has not been previously explored.

OBJECTIVE

To examine whether self-reported risk is associated with hospitalizations in patients with COPD.

METHODS

A secondary analysis from a prospective observational cohort study of veterans with COPD. Participants completed questions from the Stopping Elderly Accidents, Deaths and Injuries (STEADI) tool kit at either baseline or at the end of the 12-month study. A prospective or cross-sectional analysis examined the association between responses to the STEADI questions and risk of all-cause or COPD hospitalizations.

RESULTS

Participants (N = 388) had a mean age of 69.6 ± 7.5 years, predominately male (96 %), and 144 (37.1 %) reported having fallen in the last year. More than half reported feeling unsteady with walking (52.6 %) or needing to use their arms to stand up from a chair (61.1 %). A third were concerned about falling (33.3 %). Three questions were associated with all-cause (not COPD) hospitalization in both unadjusted and adjusted cross-sectional analysis (N = 213): "fallen in the past year" (IRR 1.77, 95 % CI 1.10 to 2.86); "unsteady when walking" (IRR 1.88, 95 % CI 1.14 to 3.10); "advised to use a cane or walker" (IRR 1.89, 95 % CI 1.16 to 3.08).

CONCLUSIONS

The prevalence of self-reported falling risk was high in this sample of veterans with COPD. The association between falling risk and all-cause hospitalization suggests that non-COPD hospitalizations can negatively impact intrinsic risk factors for falling. Further research is needed to clarify the effects of all-cause hospitalization on falling risk in persons with COPD.

Airborne Particulate Matter Size and Chronic Obstructive Pulmonary Disease Exacerbations: A Prospective, Risk-Factor Analysis Comparing Global Initiative for Obstructive Lung Disease 3 and 4 Categories

Current research primarily emphasizes the generalized correlations between airborne pollution and respiratory diseases, seldom considering the differential impacts of particular particulate matter sizes on chronic obstructive pulmonary disease (COPD) exacerbations in distinct Global Initiative for Obstructive Lung Disease (GOLD) categories. This study hypothesizes a critical association between particulate matter sizes (PM 1.0, PM 2.5, and PM 10) and exacerbation frequency in COPD patients categorized under GOLD 3 and GOLD 4, with a potential augmenting role played by proximity to main roads and industrial areas. This research aspires to offer a nuanced perspective on the exacerbation patterns in these groups, setting the stage for targeted intervention strategies. Utilizing a prospective design, this study followed 79 patients divided into GOLD 3 (n = 47) and GOLD 4 (n = 32) categories. The participants were monitored for ten days for daily activity levels, symptoms, living conditions, and airborne particulate matter concentrations, with spirometric evaluations employed to measure lung function. Statistical analyses were used to identify potential risk factors and significant associations. The analysis revealed substantial disparities in airborne particulate matter sizes between the two groups. The mean PM 1.0 concentration was notably higher in GOLD 4 patients (26 µg/m3) compared to GOLD 3 patients (18 µg/m3). Similarly, elevated PM 2.5 levels were observed in the GOLD 4 category (35 µg/m3) in contrast to the GOLD 3 category (24 µg/m3). A vital finding was the increased frequency of exacerbations in individuals residing within 200 m of main roads compared to those living further away (OR = 2.5, 95% CI: 1.5-4.1). Additionally, patients residing in homes smaller than 50 square meters demonstrated a greater frequency of exacerbations. Spirometry results corroborated the exacerbated condition in GOLD 4 patients, indicating a significant decline in lung function parameters compared to the GOLD 3 group. This study substantiates a significant association between airborne particulate matter sizes and exacerbation frequencies in COPD patients, particularly accentuating the increased risk in GOLD 4 patients. Our findings underscore the pivotal role of environmental factors, including the size of living areas and proximity to main roads, in influencing COPD exacerbations. These results suggest the need for personalized healthcare strategies and interventions, which account for environmental risk factors and the distinctions between GOLD 3 and GOLD 4 categories of COPD patients.

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.

Is liver regeneration key in hepatocellular carcinoma development?

The liver is the largest organ of the mammalian body and has the remarkable ability to fully regenerate in order to maintain tissue homeostasis. The adult liver consists of hexagonal lobules, each with a central vein surrounded by six portal triads localized in the lobule border containing distinct parenchymal and nonparenchymal cells. Because the liver is continuously exposed to diverse stress signals, several sophisticated regenerative processes exist to restore its functional status following impairment. However, these stress signals can affect the liver's capacity to regenerate and may lead to the development of hepatocellular carcinoma (HCC), one of the most aggressive liver cancers. Here, we review the mechanisms of hepatic regeneration and their potential to influence HCC development.

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.

Clinical assessment of balance and functional impairments in people with stable chronic obstructive pulmonary disease: a systematic review and meta-analysis

The objective of this study was to compare the balance and functional capacity between stable chronic obstructive pulmonary disease (COPD) patients versus healthy controls using clinical tests. A comprehensive search of PubMed/MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), Embase and Web of Science was conducted from inception to 21 January 2022. Studies reporting the association between COPD status and balance or functional capacity using clinical tests were included. Two independent reviewers examined the titles and abstracts, extracted the data using a standardised form, and assessed the risk of bias of the included articles. A total of 27 studies with 2420 individuals with stable COPD were included. Overall, the risk of bias in the included studies was low to moderate. The meta-analysis showed a higher history of falls in individuals with COPD (odds ratio 1.59, 95% CI 1.25-2.02). Furthermore, an overall effect in favour of the healthy controls was observed in the Timed Up and Go (mean difference: 2.61 s, 95% CI 1.79-3.43), Berg Balance Scale (mean difference: -6.57 points, 95% CI -8.31 to -4.83), static balance tests (standardised mean difference: -1.36, 95% CI -2.10 to -0.62) and the 6-min walk test (mean difference: -148.21 m, 95% CI -219.37 to -77.39). In conclusion, individuals with stable COPD have worse balance and functional capacity compared to healthy controls. These results may guide clinicians to elaborate on therapeutic strategies focused on screening of balance and functional impairments. This is in addition to generating rehabilitation guidelines aimed at reducing the risk of falling in people with COPD.

Dancing for Health and Wellbeing: A Feasibility Study of Examining Health Impacts of Online Dancing among Pulmonary Fibrosis Patients

BACKGROUND

Physical activity (PA) is recommended in the management of patients with pulmonary fibrosis (PF) to improve health outcomes. Dance is one such form of PA which is meaningful, valuable, enjoyable and has demonstrated positive physical and mental health effects.

METHODS

With pre-post design, 16 patients, members of the Irish Lung Fibrosis Association, were enrolled in this study. Once weekly, 75-min dance sessions were delivered for eight weeks via Zoom by an experienced choreographer. Participants completed Chronic Respiratory Questionnaire Self-Administered Standardised Format (CRQ-SAS) and European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L) to assess self-rated quality of life. A paired-sample t-test was employed to assess the mean differences between the pre-and post-intervention scores.

RESULTS

Most patients (78.57%) were aged over 60 years; with 71.43% diagnosed with pulmonary fibrosis more than 3 years ago. We performed an analysis of 10/16 participants who completed the intervention (5 males, 5 females). On CRQ-SAS scale we found, (a) dyspnoea-small to moderate magnitude improvement of 0.5-1.0 among 50%, (b) fatigue-small to moderate magnitude improvement of 0.5-1.0 among 40%, (c) emotional function-small to high magnitude improvement of 0.5-2.0 among 50%, (d) mastery-small magnitude improvement of 0.5 among 20%. Participants reported their health moderate to best on Visual Analogue Scale of EQ-5D-3L which improved by 1-3 scale among 40%. Mental health improved as percentage of not feeling anxious or depressed rose post event from 42.86% to 72.73%.

CONCLUSION

Our findings demonstrate that a virtual dance intervention is acceptable, enjoyable and feasible for improving health outcomes among PF patients. More organised and continuous events in future may reveal cost-benefit ratio and impact on health outcomes.

Age and Sex Differences in Balance Outcomes among Individuals with Chronic Obstructive Pulmonary Disease (COPD) at Risk of Falls

No previous research has examined age and sex differences in balance outcomes in individuals with chronic obstructive pulmonary disease (COPD) at risk of falls. A secondary analysis of baseline data from an ongoing trial of fall prevention in COPD was conducted. Age and sex differences were analyzed for the Berg Balance scale (BBS), Balance Evaluation System Test (BEST test) and Activities-specific Balance Confidence Scale (ABC). Overall, 223 individuals with COPD were included. Females had higher balance impairments than males [BBS: mean (SD) = 47 (8) vs. 49 (6) points; BEST test: 73 (16) vs. 80 (16) points], and a lower confidence to perform functional activities [ABC = 66 (21) vs. 77 (19)]. Compared to a younger age (50-65 years) group, age >65 years was moderately associated with poor balance control [BBS (r = - 0.37), BEST test (r = - 0.33)] and weakly with the ABC scale (r = - 0.13). After controlling for the effect of balance risk factors, age, baseline dyspnea index (BDI), and the 6-min walk test (6-MWT) explained 38% of the variability in the BBS; age, sex, BDI, and 6-MWT explained 40% of the variability in the BEST test; And BDI and the 6-MWT explained 44% of the variability in the ABC scale. This study highlights age and sex differences in balance outcomes among individuals with COPD at risk of falls. Recognition of these differences has implications for pulmonary rehabilitation and fall prevention in COPD, particularly among females and older adults.

Balance impairment and cognitive dysfunction in patients with chronic obstructive pulmonary disease under 65 years

Objective

Balance and cognitive problems may develop in COPD. Studies investigating cognitive functions are mostly in elderly patients, and the number of studies on balance impairment is less than studies about cognitive dysfunction in COPD. We aimed to evaluate both balance and cognitive functions in patients with COPD under 65 years.

Methods

A total of 60 COPD patients and 60 healthy control group were enrolled. The patients with COPD were divided into two groups due to dyspnea severity. Demographic data and dyspnea scores of all patients were recorded. BECK depression scale, standardized Mini Mental Test (MMT), and BERG balance scale were applied to the individuals. Factors affecting BERG balance scale were evaluated.

Results

BERG balance scale and MMT values were found to be significantly lower in patients with COPD compared with the control group (p = 0.009). It was observed that the mean values of BERG balance scale and MMT were significantly low in the severe dyspnea group. BERG scale had significant correlations with MMT (rho = 0.331, p = 0.001), BECK (rho = −0.222, p = 0.016), age (rho = −0.318, p = 0.018), MMRC (rho = −0.368, p < 0.001), CAT (rho = −0.338, p = 0.008), FEV1% (rho = 0.307, p = 0.017), SpO₂ (rho = 0.448, p < 0.001), and number of hospitalization per year (rho = −0.316, p = 0.014). According to the results of multiple linear regression analysis, the effect of oxygen saturation on BERG was found to be statistically significant (B = 0.512, p = 0.008).

Conclusions

Balance tests in patients with COPD under the age of 65 are significantly low when compared with healthy controls at the same age. Balance and cognitive functions are significantly associated with each other. It may be beneficial to perform balance and cognitive function tests earlier even at the beginning of the treatment period of COPD, and strategies should be planned to prevent the progression of functional losses.

Balance impairment and lower limbs strength in patients with COPD who fell in the previous year

Fall-related causes in patients with COPD might be associated to functional balance impairments and greater disease severity. We aimed to evaluate the reasons for falls in patients with COPD who had presented any fall during the previous year. This is a cross-sectional study. All COPD's GOLD classifications (mild, moderate, severe, and very severe) patients were recruited. In order to participate, patients ought to be clinically stable and without any exacerbation within 30 days prior to study entry. History of falls was self-reported by patients through an interview. Pre and post bronchodilator (salbutamol 400 μg) spirometry was performed. All patients accomplished postural balance tests such as the Berg Balance Scale, Falls Efficacy Scale-International, Time up and Go, Functional Reach test, Tinetti test and Chalder Scale; furthermore, lower limbs muscle strength (muscle dynamometry) and the COPD Assessment Test (CAT) were assessed. Ninety-six patients with COPD were evaluated and divided into two groups stratified according to any positive history of falls in the previous year. Patients with COPD who had any fall in the previous year presented older age (p=0.01), higher BMI (p=0.04) and worse pulmonary function than those who did not fall. The risk of falls was increased in patients with lower muscle strength in the lower limbs (OR 2.9, CI 95%;1.6 to 3.9), age greater than 65 years (OR 2.7, CI 95%;1.3 to 3.4), BMI greater than 28.8 kg/m2 (OR 3.2, CI 95%;1.1 to 5.6), very severe airway obstruction (OR 3.9, CI 95%;2.2 to 3.9) and fatigue (OR 3.2, CI 95%;1.5 to 5.3). Impaired body balance, reduced lower limb strength, disease severity, presence of fatigue and elevated BMI are important factors for falls in patients with COPD.

Balance Function in Patients With COPD: A Systematic Review of Measurement Properties

To conduct an overview, evaluation, and synthesis of measurement properties of instruments assessing balance of COPD patients. Electronic searches were performed in Web of Science, Scopus, Embase, PubMed, CINAHL, PsycINFO, WanFang, and China National Knowledge Infrastructure databases up to the end of April 2021. Two reviewers independently evaluated the methodological quality using the Consensus-based Standards for the Selection of Health Status Measurement Instrument checklist, and rated the overall quality level of evidence was graded based upon a modified Grades of Recommendation, Assessment, Development, and Evaluation approach. Finally, 12 instruments were included. The Berg Balance Scale and the Timed Up and Go test were the most frequently used tools to evaluate balance. None of 12 instruments provide any information regarding cross-cultural validation or criterion validation. High-quality studies exploring measurement properties with a focus on the criterion validity and cross-cultural validity of balance measurements in COPD patients are warranted.

Gait and functional balance in non-CF bronchiectasis

BACKGROUND

The decline in ambulatory activities and negative alterations in gait characteristics may impair balance and increase fall risk in obstructive lung diseases. Few studies have evaluated balance and gait parameters in individuals with bronchiectasis.

PURPOSE

This study aimed to compare the gait parameters and functional balance in individuals with non-cystic fibrosis (CF) bronchiectasis and healthy subjects.

METHODS

This cross-sectional and retrospective study analyzed data from 22 individuals with non-CF bronchiectasis and 32 healthy controls recorded between July 2019 and July 2020. Functional balance was assessed using the Timed Up and Go (TUG) test. Gait parameters were evaluated using the Biodex Gait Trainer. Step cycle (s), gait speed (m/s), the number of steps per minute, and ambulation index were measured for 6 min.

Results The TUG time (s) was significantly longer (p = .019, effect size = 0.66), and gait speed (m/s) (p ˂ 0.001, effect size = 2.47), step cycle (s) (p ˂ 0.001, effect size = 2.23), and ambulation index (p ˂ 0.001, effect size = 2.56) were significantly reduced in individuals with non-CF bronchiectasis compared with healthy controls.

CONCLUSION

Non-CF bronchiectasis is related to unfavorable changes in gait characteristics, such as slower gait speed and the decreased average step cycle. In addition, impairment in functional balance and mobility exists in a small percentage of adults with non-CF bronchiectasis. In comprehensive pulmonary rehabilitation, balance and gait evaluations should be included to prevent falls in adults with non-CF bronchiectasis.

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.

Effects of specific inspiratory muscle training combined with whole-body endurance training program on balance in COPD patients: Randomized controlled trial

PURPOSE

This study aims to assess the effect of inspiratory muscle training (IMT) combined with endurance training (ET) on balance in patients with chronic obstructive pulmonary disease (COPD).

METHODS

We studied 32 male patients (62 ± 6 years) with moderate to very severe COPD. They were randomly assigned to an experimental group (IMT+ET) n = 16 or a control group (ET) n = 16 with similar characteristics. The evaluations were carried out at inclusion and after eight weeks of the training period. Functional balance was assessed by the Berg Balance Scale (BBS), the Timed-up and Go (TUG), the Single Leg Stance test (SLS), and the Activities-specific Balance Confidence (ABC) scale. The strength of the inspiratory muscles (PImax) was assessed by maximal inspiratory mouth pressure. Functional exercise performance was assessed by the 6 minutes walking test (6MWT). IMT program consists in performing two daily sets of 30 inspirations with 50% of PImax increased by 10% every two weeks. ET program consists in performing 30 min treadmill exercise at 60% to 80% of the average speed achieved during the 6MWT three days per week.

RESULTS

After the training period, the experimental group demonstrated greater improvements in BBS (IMT+ET vs. ET; p = 0.019), and in ABC (IMT+ET vs. ET; p = 0.014). However, no significant differences between groups were observed for TUG, SLS, and 6MWT. There was a significant difference between groups in PImax (IMT+ET vs. ET; p = 0.030). Significant moderate correlations were obtained between ΔPImax and ΔBBS for both groups (IMT+ET: r = 0.624, p = 0.010; ET r = 0.550, p = 0.027) as well as for ΔABC but only in the experimental group (IMT+ET: r = 0.550, p = 0.027).

CONCLUSION

Compared to ET alone, the results suggest that IMT combined with ET enhances inspiratory muscle function and functional balance according to BBS and ABC in patients with COPD. We suggest that inspiratory muscle training might be introduced as additional training to pulmonary rehabilitation programs aimed at improving balance in COPD patients.

TRIAL REGISTRATION

The trial registry name: Clinical Trials; Registration number: NCT04084405; URL: https://clinicaltrials.gov/ct2/show/NCT04084405.

Static and dynamic balance impairment and relationship with disease-related factors in patients with chronic obstructive pulmonary disease : A cross-sectional study

BACKGROUND

Disease and aging-related factors may predispose chronic obstructive pulmonary disease (COPD) patients to impaired balance, although the underlying determinants of impaired balance in COPD patients are still unknown. The purpose of this study was to identify the determinants of impaired balance in COPD patients. Also, we aimed to determine which balance measures (clinical or laboratory tests) are more indicative in determining balance impairment in these patients.

METHODS

This cross-sectional study recruited 24 patients with moderate to severe COPD and 24 age-matched healthy subjects. Participants were evaluated regarding demographic and clinical data, previous falls history, lower limb muscle strength, exercise capacity, physical activity and balance level.

RESULTS

COPD patients exhibited significantly a longer test duration on timed up and go test, a higher sway index on the postural stability and lower directional control score on the limit of stability of Biodex balance system (all, p < 0.001) compared to healthy controls, whereas there was no difference in Berg balance scale score between groups (p > 0.05). Balance impairment of the patient group was significantly associated with nonpulmonary conditions, such as physical activity level, exercise capacity, lower limb muscle strength, and with fall history. Also, COPD patients represented significantly lower physical activity level and exercise capacity, weaker lower limb muscle strength than healthy controls (all, p < 0.001).

CONCLUSIONS

Patients with moderate to severe COPD exhibit apparently important reductions in balance control that is directly associated with nonpulmonary consequences and fall history. These results may be extremely important to fall prevention and to guide the development of interventions for this population.

The relationship between height of vertical jumps, functionality and fall episodes in patients with chronic obstructive pulmonary disease: A case-control study

This study aimed to compare the height of jumps and functional parameters in patients with chronic obstructive pulmonary disease (COPD) to those in healthy people, in addition to assessing the relationship among variables in patients with COPD. Twenty patients with COPD (forced expiratory volume [FEV1] % of predicted: 39.98 ± 11.69%; age: 62.95 ± 8.06 years) and 16 healthy people (FEV1% of predicted: 97.44 ± 14.45%; age: 59.94 ± 6.43 years) were evaluated, and all participants performed the Squat Jump (SJ) and Counter Movement Jump (CMJ) tests to assess rapid force considering the jumping height. Functional capacity was assessed using the self-selected walking speed tests, walking speed in 10 m, walking test in 6 min, balance on one leg, sitting and standing, timed up and go, and a stair-climbing test. In addition, the questionnaires on recall of falls, Falls Efficacy Scale-International (concern with falling), International Physical Activity Questionnaires, and Saint George Respiratory Questionnaire were administered. The height of the jumps showed no difference between the groups, but the COPD group performed worse in most functional tests and was more afraid of falling. The number of falls was correlated with height in the SJ (r = -0.51) and CMJ (r = -0.62) jumps (p < 0.05), and with the performance in different functional tests. We suggest that interventions targeting rapid force may bring improvements in functional mobility and physical fitness as well as reducing fall episodes in patients with COPD.

The Investigation of Falls and Balance from the Perspective of Activities of Daily Living in Patients with COPD

The aim of this study was (1) to compare the activities of daily living (ADLs), perceived falling risk and balance in chronic obstructive pulmonary disease (COPD) patients with or without falling history and (2) to investigate the relationship between ADLs and balance. Fourteen patients with COPD with a history of falling whose mean falling frequency was 2.64 ± 0.74 times in the last 12-months (fallers) and 14 age and sex-matched patients with COPD with no history of falling (non-fallers) were included. The outcome measures were the London Chest Activity of Daily Living (LCADL) scale, Activities-Specific Balance Confidence (ABC) scale, Berg Balance Scale (BBS), 6-minute walking test, and quadriceps-femoris strength. Fallers reported increased dyspnoea perception in ADLs, decreased balance confidence, and disturbed balance compared with non-fallers (p < 0.05). A strong correlation was found between the LCADL scale item score (dressing the upper body) and the BBS total score (rho = -0.81, p = 0.001) in fallers. The LCADL scale item score (going out socially) was significantly correlated with the total score of the ABC scale (rho = -0.61, p = 0.001). Moderate correlations were found between the LCADL scale item scores (dressing the upper body, washing hair, and walking up stairs) and the BBS total score (p < 0.003). This study demonstrated that increased severity of dyspnoea perception during ADLs is associated with impaired balance and poor balance confidence, regardless of functional capacity and peripheral muscle strength in patients with COPD. The balance confidence was low in functional mobility-based activities in patients with COPD with a history of falling.

Evaluation of balance in patients with chronic obstructive pulmonary disease with practical tests

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) have impaired balance and hence fall more frequently. Easy application of balance evaluation tests can prevent the loss of time in the outpatient clinic for patients with COPD. In this study, we aimed to compare the efficacy of Berg Balance Scale (BBS), a time-consuming but a widely used test, with other easy-to-perform tests such as the Single Leg Stance (SLS), Five Repetition Sit to Stand (5STS), Four Step Square (FSST), and Timed Up and Go (TUG) tests.

METHODS

A total of 71 patients with COPD and 70 control subjects with matching demographic characteristics were included in the study. All patients undertook pulmonary function tests and their scores of 6-min walk-test (6MWT), modified Medical Research Council (mMRC) dyspnoea scale, COPD assessment questionnaire (CAT) and body mass index (B) were recorded. In addition, the severity of airway obstruction (O), the dyspnoea severity (D) and exercise capacity (E) (BODE) index scores were measured. All patients with COPD were classified into four groups, A to D, based on the GOLD 2017 criteria. All subjects undertook the BBS, SLS, 5STS, FSST and TUG tests.

RESULTS

Balance tests revealed increased balance impairment in patients with COPD in comparison with the control subjects (P < .05). The BBS, SLS, FSST and TUG examinations suggested that balance impairment was frequent in Groups C and D patients with COPD (P < .05). FSST and TUG had the highest correlation with BBS (r = -.812 and -.842 and P < .001 and <.001, respectively). The results of FSST and TUG were the closest to those of BBS test.

CONCLUSIONS

FSST and TUG tests can be applied for the assessment of bodily balance status among patients with COPD in outpatient clinics.

Contribution of lower limb muscle strength to walking, postural sway and functional performance in elderly women

BACKGROUND: Aging-related deterioration of the lower limb muscle strength could highly influence the functional performance of elderly individuals. OBJECTIVE: To investigate how advancing age impacts the lower limb muscle strength and consequently affects the balance and walking performance. METHODS: Twenty-seven community-dwelling elderly females underwent isokinetic ankle dorsi/plantar flexion (ADF/APF), inversion/eversion (AIN/AEV), knee flexion/extension (KFL/KEX), hip flexion/extension (HFL/HEX), and abduction/adduction (HAB/HAD) tests, the six-minute walk test, open-eyed biped balance test on foam rubber and the performance-oriented mobility assessment (POMA). RESULTS: The Pearson’s product-moment correlation coefficients demonstrated that advancing age negatively influenced the relative work and moment produced in all the muscle groups, the POMA score (r=-0.51), walking speed (r=-0.62), and the vertical (r= 0.55) and anteroposterior (r= 0.54) postural sway velocities. The peak moment and work values of AINs and APFs; KFLs and KEXs; and HABs, HFLs, and HEXs showed a significantly positive correlation with the walking speed (α⩽ 0.05). CONCLUSION: The strength of HFLs, HEXs and HABs, as the important contributors to the walking performance, underwent attenuation as the age increased, consequently resulting in impairments of stepping profiles of elderly females. Elderly females are needed to be trained to reach the optimum levels of lower limb muscular strength to overcome premature incapacitation and have control over their independence in daily activities.

Falls prevalence and risk factors in people with chronic obstructive pulmonary disease: A systematic review

BACKGROUND

Falls are frequent in people with chronic obstructive pulmonary disease (COPD) and related to increased morbidity, mortality, and health care costs in older adults. This systematic review aims to synthesise the falls outcomes and to examine risk factors for falls in the COPD literature.

METHODS

The protocol was registered in the Prospective Register of Systematic Reviews (PROSPERO: CRD42015017257). Searches were updated and operated in five electronic databases in December 2019 for studies reporting falls outcomes and risk factors in people with COPD. Meta-analyses were conducted on the prevalence of fallers and frequent fallers. Quality assessment appraised the risk of bias of included articles.

RESULTS

Twenty-three studies met the eligibility criteria and were retained after the full-text review. In the meta-analyses, the pooled prevalence of COPD fallers was 30% (95%CI 19%-42%), and the pooled prevalence of frequent fallers (≥2 falls in the analysed period of occurrence) was 24% (95%CI 2%-56%). The falls incidence rate in stable COPD varied from 1.17 to 1.49 falls/person-year. Different study methodologies were identified. Age, female gender, falls history, the number of medications, comorbidities, coronary heart disease, use of supplemental oxygen, impaired balance performance and smoking history were risk factors for falls identified in stable COPD.

CONCLUSION

Prevalence of fallers, frequent fallers, and falls incidence rate have been reported in the COPD literature using a varying methodology. People with stable COPD present with ageing and disease-related risk factors for falls. Further research using the recommended prospective recording is needed in COPD.

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.

Phenotypic Characteristics of Patients With Chronic Obstructive Pulmonary Disease After Stratification for the Short Physical Performance Battery Summary Score

OBJECTIVE

To assess the phenotypic characteristics of patients with chronic obstructive pulmonary disease (COPD) after stratification for Short Physical Performance Battery (SPPB) summary scores and to determine phenotypic characteristics of the SPPB summary score at the start of pulmonary rehabilitation (PR).

DESIGN

Retrospective, cross-sectional.

SETTING

Baseline assessment for PR program.

PARTICIPANTS

Patients with COPD (n=900; age 65±8y, 52% male, forced expiratory volume in the first second of expiration, 43% [interquartile range, 31%-62%] predicted).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Patients were stratified according to their SPPB summary scores into low-performance (LP), moderate-performance (MP), or high-performance (HP) groups. Furthermore, lung function, arterial blood gases, body composition, physical capacity, lower limb muscle strength and endurance, and symptoms of anxiety and depression were assessed.

RESULTS

Generally, physical capacity and muscle function were lower and scores for symptoms of anxiety and depression were higher in LP patients than MP and HP patients (all values, P<.01). However, 25% of HP patients with COPD scored high on symptoms of anxiety and/or depression (≥10 points), and HP patients still had on average an impaired physical capacity (median, 6-minute walk test [6MWT] distance of 69% predicted). Furthermore, age and 6MWT distance (m) were the only independent predictors in a multivariate regression model, explaining 29% of the variance in SPPB summary score.

CONCLUSIONS

In COPD, LP patients have the worst physical and emotional functioning. However, HP patients can still exhibit physical and emotional impairments. Because the explained variance in SPPB summary score is low, SPPB should not be considered as a test to discriminate between patients with COPD with a low or preserved physical capacity and emotional status.

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.

Diagnostic ability of the Timed Up & Go test for balance impairment prediction in chronic obstructive pulmonary disease

Background

Balance assessment is now recommended by clinical practice guidelines, specific tests have yet to be suggested. The Timed Up and Go (TUG) test is a simple measure of balance status and functional mobility. Nowadays, we need more data of an optimum cut off point of TUG time for detecting balance impairment in patients with chronic obstructive pulmonary disease (COPD). Thus the aim of this study was to evaluate the diagnostic ability relative to balance impairment of the TUG in subjects with COPD.

Methods

The cross-sectional study was conducted in stable COPD patient at Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand from November 2015 to October 2017. Balance impairment test was measured using the Berg Balance Scale (BBS), a score of ≤45 indicates balance impairment. The TUG was evaluated using sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR−), Youden’s index, and the area under receiver operating characteristic curve (AUROC) from various points of TUG to identify the optimum cut-off point for detecting balance impairment. Multivariable logistic regressions were performed to identify the optimum cut off point of TUG test time for prediction of balance impairment in COPD.

Results

One hundred and eighteen smoking related COPD subjects 86 (72.9% male) with a mean age of 73.5±8.1 years were included in this study. Univariable analysis showed that the AUROC of TUG test to indicate those who had impaired balance was 0.93 [95% confidence interval (CI): 0.88, 0.98]. A cut off point of TUG test time ≥12 seconds had sensitivity, specificity, LR+, LR−, Youden’s index, and AUROC of 95.8%, 90.4%, 10.01, 0.05, 86.2, and 0.93 for detecting balance impairment, respectively. Multivariable analysis identified the TUG test time ≥12 seconds was the best predictor of balance impairment in COPD patients with adjusted risk ratio (RR) of 25.2 (95% CI: 1.6, 312.0, P=0.021) and, the AUROC was 0.98 (95% CI; 0.96, 1.00).

Conclusions

Our study indicates the TUG test time ≥12 seconds has a high diagnostic ability for balance impairment prediction in COPD. The result supports a potential role for this simple test to be incorporated into routine COPD assessment to stratify patients’ balance.

Associations Between Factors Across Life and One-Legged Balance Performance in Mid and Later Life: Evidence From a British Birth Cohort Study

Introduction: Despite its associations with falls, disability, and mortality, balance is an under-recognized and frequently overlooked aspect of aging. Studies investigating associations between factors across life and balance are limited. Understanding the factors related to balance performance could help identify protective factors and appropriate interventions across the life course. This study aimed to: (i) identify socioeconomic, anthropometric, behavioral, health, and cognitive factors that are associated with one-legged balance performance; and (ii) explore how these associations change with age.

Methods: Data came from 3,111 members of the MRC National Survey of Health and Development, a British birth cohort study. Multilevel models examined how one-legged standing balance times (assessed at ages 53, 60–64, and 69) were associated with 15 factors across life: sex, maternal education (4 years), paternal occupation (4 years), own education (26 years), own occupation (53 years), and contemporaneous measures (53, 60–64, 69 years) of height, BMI, physical activity, smoking, diabetes, respiratory symptoms, cardiovascular events, knee pain, depression and verbal memory. Age and sex interactions with each variable were assessed.

Results: Men had 18.8% (95%CI: 13.6, 23.9) longer balance times than women at age 53, although this difference decreased with age (11.8% at age 60–64 and 7.6% at age 69). Disadvantaged socioeconomic position in childhood and adulthood, low educational attainment, less healthy behaviors, poor health status, lower cognition, higher body mass index (BMI), and shorter height were associated with poorer balance at all three ages. For example, at age 53, those from the lowest paternal occupational classes had 29.6% (22.2, 38.8) worse balance than those from the highest classes. Associations of balance with socioeconomic indicators, cognition and physical activity became smaller with age, while associations with knee pain and depression became larger. There were no sex differences in these associations. In a combined model, the majority of factors remained associated with balance.

Discussion: This study identified numerous risk factors across life that are associated with one-legged balance performance and highlighted diverse patterns of association with age, suggesting that there are opportunities to intervene in early, mid and later life. A multifactorial approach to intervention, at both societal and individual levels, may have more benefit than focusing on a single risk factor.

Balance Impairment and Effectiveness of Exercise Intervention in Chronic Obstructive Pulmonary Disease-A Systematic Review

OBJECTIVE

To systematically review the evidence for balance impairment and effectiveness of interventions on balance in people with chronic obstructive pulmonary disease (COPD).

DATA SOURCES

Four electronic databases (Scopus, CINAHL, PubMed, Cochrane Library databases) were searched from inception until June 30, 2019.

STUDY SELECTION

Two reviewers independently searched with keywords focusing on COPD, postural control, and exercise. Cross-sectional studies related to balance and randomized controlled trials (RCTs) related to the effectiveness of exercise intervention on balance outcomes were included.

DATA EXTRACTION

Two reviewers independently extracted data of balance impairment on participants, exercise training on balance outcome measures. Methodological quality of cross-sectional studies was assessed using the National Institutes of Health (NIH) Quality Assessment Tool. Methodological quality of RCTs was assessed using the Physiotherapy Evidence Database (PEDro) scale and bias was analyzed using the Cochrane risk of bias.

DATA SYNTHESIS

A narrative review with descriptive synthesis was used. Fifteen cross-sectional studies and 4 RCTs met the final inclusion criteria. The quality of 10 cross-sectional studies were rated as moderate to high (NIH score≥7). Most studies demonstrated impaired balance in people with COPD than in people without COPD. The quality of all included RCTs was good to excellent (PEDro score=6-9). One RCT had a low risk of bias. Generally, pulmonary rehabilitation program combined with balance training, Tai Chi, and cycling exercise showed significant improvement in balance in people with COPD.

CONCLUSIONS

Impaired balance is evident in people with COPD. Available RCTs suggest that exercise interventions may improve balance performance in COPD patients. However, more research on the effect of exercise interventions on balance in COPD patients is still required.

Chronic obstructive pulmonary disease patients increase medio-lateral stability and limit changes in antero-posterior stability to curb energy expenditure

BACKGROUND

A relationship exists between step width and energy expenditure, yet the contribution of dynamic stability to energy expenditure is not completely understood. Chronic obstructive pulmonary disease (COPD) patients' energy expenditure is increased due to airway obstruction. Further, they have a higher prevalence of falls and balance deficits compared to controls.

RESEARCH QUESTION

Is dynamic stability different between COPD patients and controls; and is the association between dynamic stability and energy expenditure different between groups?

METHODS

Seventeen COPD patients (64.3 ± 7.6years) and 23 controls (59.9 ± 6.6years) walked on a treadmill at three speeds: self-selected walking speed (SSWS), -20%SSWS, and +20%SSWS. Mean and variability (standard deviation) of the anterior-posterior (AP) and medio-lateral (ML) margins of stability (MOS) were compared between groups and speed conditions, while controlling for covariates. Additionally, their association to metabolic power was examined.

RESULTS

The association between stability and power did not significantly differ between groups. However, increased metabolic power was associated with decreased MOS AP mean (p < 0.0001), independent of speed. Increased MOS AP variability (p = 0.01) and increased SSWS (p's < 0.05) were associated with increased metabolic power. The MOS ML mean for COPD patients was greater than that of healthy patients (p = 0.02). MOS AP mean decreased as speed increased and differed by group (p = 0.048). For COPD patients, a plateau was observed at SSWS and did not decrease further at +20%SSWS compared to controls. MOS AP variability (p < 0.0001), MOS ML mean (p < 0.0001), and MOS ML variability (p = 0.003) decreased as speed increased and did not differ by group.

SIGNIFICANCE

Patients with COPD operate at the upper limit of their metabolic reserve due to an increased cost of breathing. To compensate for their lack of stability, they walked with larger margins of stability in the ML direction, instead of changing the stability margins in the AP direction, due to its association with energy expenditure.

Subjects With COPD Walk With Less Consistent Organization of Movement Patterns of the Lower Extremity

BACKGROUND

The inherent stride-to-stride fluctuations during walking are altered in the aging population and could provide insight into gait impairments and falls in patients with COPD. Stride-to-stride fluctuations are quantified two ways: variability of the fluctuations (eg, standard deviation), and movement patterns within the fluctuations. Our objective was to investigate stride-to-stride fluctuations by evaluating the variability and movement patterns of lower limb joints in subjects with COPD compared to subjects without COPD as control subjects.

METHODS

In this cross-sectional study, 22 subjects with COPD (age 63 ± 9 y; FEV₁ 54 ± 19% predicted) and 22 control subjects (age 62 ± 9 y; FEV₁ 95 ± 18% predicted) walked for 3 min on a treadmill while their gait was recorded. The amount of variability (ie, standard deviation and coefficient of variation) and movement patterns (ie, predictability and consistency in organization) were quantified for the range of motion and joint angle of the hip, knee, and ankle, at 3 walking speeds (ie, self-selected, fast, and slow). General linear mixed models were used for analysis.

RESULTS

Control subjects had more consistent organization of the hip and knee joint movement patterns compared to subjects with COPD (P = .02 and P = .02, respectively). Further, control subjects adapted to speed changes by demonstrating more consistent organization of movement patterns with faster speeds, whereas subjects with COPD did not. At the fast walking speed, subjects with COPD demonstrated less consistent organization of knee and hip joint movement patterns as compared to control subjects without COPD (P = .03 and P = .005, respectively). The amount of variability did not differ between groups.

CONCLUSIONS

Although subjects with COPD did not demonstrate decreased amount of variability, their hip and knee joint movement patterns were less consistent in organization during walking. Reduced consistency in organization of movement patterns may be a contributing factor to falls and mobility problems experienced by patients with COPD.

A TUG Value Longer Than 11 s Predicts Fall Risk at 6-Month in Individuals with COPD

Risk of a fall is increased in individuals with chronic obstructive pulmonary disease (COPD), and is usually evaluated using the Berg Balance Scale (BBS), but this is difficult to perform in everyday clinical practice. We aimed to prospectively predict short-term fall recurrence in COPD patients using a predetermined cut-off value of the Timed Up and Go test (TUG). In stable COPD patients, we collected self-reported records of the number of falls in the previous year, and measured TUG and BBS scores for each individual. Records of fall recurrence were obtained prospectively at 6-months after the initial evaluation. Among the 50 patients recruited, 23 (46%) had at least one fall during the past year. The optimal diagnosis value for the TUG to detect a fall was 10.9 s with a sensitivity of 100% and a specificity of 97%. A cut-off of 11 s predicted fall recurrence with high sensitivity and specificity (93% and 74%, respectively). The TUG as well as the BBS score detected fallers, and a cut-off value of 11 s predicted fall recurrence. TUG could be easily incorporated into the scheduled functional evaluations of COPD patients, could predict the risk of a fall and when appropriate, could guide specific balance training exercises to prevent fall.

Comparison of reaction time and functional balance in chronic obstructive pulmonary disease and healthy participants

BACKGROUND

Reaction time is one of the components of functional balance and could contribute to balance impairment. Information regarding this relationship is scant among Chronic Obstructive Pulmonary Disease (COPD) participants.

OBJECTIVES

To compare stepping reaction time between participants with COPD and age; gender-matched healthy individuals to find out whether reaction time in COPD population is affected.

METHODS

This cross-sectional study included 41 COPD participants and 41 age and gender-matched healthy individuals. All the participants underwent measurements of stepping reaction time (SRT) and timed up and go test (TUG).

RESULTS

SRT was significantly higher in COPD participants compared to healthy individuals [median of difference- 350 milliseconds (110, 830), p < 0.001]. TUG was significantly higher in COPD participants compared to healthy individuals [median of difference = 2.82 seconds (0.34 and 4.5), p < 0.001].

CONCLUSIONS

Participants with COPD exhibit marked increase in SRT and demonstrate a deficiency in functional balance compared to the healthy participants.

Age and Disease have a Distinct Influence on Postural Balance of Patients with COPD

The postural imbalance is an extra-pulmonary condition, associated with chronic obstructive pulmonary disease (COPD). COPD affects older individuals and it is unclear whether balance abnormalities can be described as pathophysiological mechanism or aging. The present study aimed to evaluate the influence of age or disease on postural balance of patients with COPD. Patients with COPD over 50 years old were compared with age- and sex-matched healthy adults, and with sex-matched younger healthy adults (n = 30 in each group). The Modified Sensory Organization Test (mSOT) was performed in four different conditions fixed or sway-referenced surface both either with full or no vision. It was analyzed the center of pressure (CoP) variables: amplitude, velocity, root-mean-square and load asymmetry. Three-way ANOVA and post hoc analysis were performed been represented of age (older or COPD compared with younger healthy adults) or disease influences (COPD compared with older healthy groups). Main results were as follows: The CoP excursion was faster, with higher amplitude and variability progressively from COPD vs. older healthy vs. younger healthy adults (p < 0.05) showing age and disease influences (p < 0.05). Age and disease influences were also observed in the sway-referenced surface in both vision conditions. Impairment in postural balance was found related to aging and disease in patients with COPD older than 50 years.

Exercise Performance as a Predictor for Balance Impairment in COPD Patients

Background and objective: Six-minute walk test (6-MWT) is a widely used test for assessing exercise performance in chronic obstructive pulmonary (COPD). However, the association between reduced walking distance and balance impairment in COPD has not been directly investigated. Therefore, the aim of this study was to identify exercise performance as a predictor for balance impairment in COPD. Materials and Methods: The cross-sectional study was conducted at a single visit involving stable COPD patients in Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand from November 2015 to October 2017. The 6-MWT was measured for in all subjects. The prognostic confounding factors were also collected for all subjects. Balance test was measured using the Berg Balance Scale (BBS) and the Timed Up and Go (TUG) test. A cut-off score of BBS < 46 and/or the TUG ≥ 13.5 s was classified as balance impairment. Multivariable logistic regressions were performed to identify the six-minute walk distance (6-MWD) as a predictor for balance impairment in COPD. Results: Of the 176 COPD subjects assessed for eligibility, 118 COPD patients were enrolled including 86 males (72.9%) with a mean age of 73.5 ± 8.1 years. Thirty-three (28.0%) cases were classified with a balance impairment. The 6-MWD < 300 m was the predictor of balance impairment in COPD with an adjusted risk ratio of 10.10 (95%CI; 2.87, 35.61, p-value < 0.001). Conclusions: The 6-MWT is not only useful for evaluation of exercise performance, but also for prediction of balance impairment in patients with COPD. Our study suggests that the 6-MWD < 300 m is an important risk factor for balance impairment in COPD.

Faster oxygen uptake, heart rate, and ventilatory kinetics in stepping compared with cycle ergometry in patients with COPD during moderate-intensity exercise

Step tests are a stressful and feasible cost-effective modality to evaluate aerobic performance. However, the eccentric in addition to concentric muscle contractions of the legs on stepping emerge as a potential speeding factor for cardioventilatory and metabolic adjustments towards a steady-state, since eccentric contractions would prompt an earlier and stronger mechanoreceptor activation, as well as higher heart rate/cardiac output adjustments to the same metabolic demand. Moreover, shorter tests are ideal for exercise-limited subjects. Nine subjects with chronic obstructive pulmonary disease were invited to participate in comprehensive lung function tests and constant work tests performed on different days at a 90% gas exchange threshold for 6 min, in single-step tests or cycle ergometry. After careful monoexponential regression modelling, statistically relevant faster phase II time constants for oxygen uptake (45 ± 18 s vs 53 ± 17 s, p = 0.017) and minute ventilation (61 ± 13 s vs 74 ± 17 s, p = 0.027) were observed in the 6-min step tests compared with cycle ergometry, respectively. Despite an absence of heart rate time constant difference (43 ± 20 s vs 69 ± 46 s, p = 0.167), there was a significantly faster rate constant toward a steady state for heart rate (p = 0.02). In addition, 4-min compared with 6-min analysis presented similar results (p > 0.05), providing an appropriate steady-state. We conclude that step tests might elicit faster time constants compared with cycle ergometry, at the same average metabolic level, and 4-min analysis has similar mean errors compared with 6-min analysis within an acceptable range. New studies, comprising mechanisms and detailed physiological backgrounds, are necessary.

New evaluation of trunk movement and balance during walking in COPD patients by a triaxial accelerometer

Background

Individuals with COPD may experience ambulatory difficulty due to both effort intolerance arising from respiratory dysfunction and impaired balance control during walking. However, the trunk movement during walking has not been evaluated or adjusted for patients with COPD. The Lissajous index (LI) visually and numerically evaluates the left–right symmetry of the trunk movement during walking and is useful in clinical practice. In COPD patients, the LI is used as an indicator of the left–right symmetry of the trunk during walking. Here, we used the LI to evaluate the symmetry of COPD patients based on bilateral differences in mediolateral and vertical accelerations, and we investigated the correlation between the patients’ symmetry evaluation results and their physical function.

Patients and methods

Sixteen stable COPD patients (all males; age 71.3±9.2 years) and 26 healthy control subjects (15 males; age 68.2±6.9 years) participated in this study. They performed the 10-minute walk test at a comfortable gait speed wearing a triaxial accelerometer, and we measured their trunk acceleration for the evaluation of symmetry. Motor functions were also evaluated in the patients with COPD.

Results

The average mediolateral bilateral difference and LI values of the COPD patients were significantly larger than those of the healthy subjects. The COPD patients’ LI values were significantly correlated with their static balance.

Conclusion

The LI measured using a triaxial accelerometer during walking is useful in balance assessments of patients with COPD.

COPD stands for complex obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) has extensively been reported as a complex disease affecting patients' health beyond the lungs with a variety of intra- and extrapulmonary components and considerable variability between individuals. This review discusses the assessment of this complexity and underlines the importance of transdisciplinary management programmes addressing the physical, emotional and social health of the individual patient.COPD management is challenging and requires advanced, sophisticated strategies meeting the patient's individual needs. Due to the heterogeneity and complexity of the disease leading to non-linear and consequently poorly predictable treatment responses, multidimensional patient profiling is crucial to identify the right COPD patient for the right treatment. Current methods are often restricted to general, well-known and commonly used assessments neglecting potentially relevant (interactions between) individual, unique "traits" to finally ensure personalised treatment. Dynamic, personalised and holistic approaches are needed to tackle this multifaceted disease and to ensure personalised medicine and value-based healthcare.

Performance and Reproducibility of the Continuous Scale Physical Functional Performance 10 Test in Patients With Chronic Obstructive Pulmonary Disease: A CONTROLLED CROSS-SECTIONAL STUDY

PURPOSE

To compare the performances of patients with chronic obstructive pulmonary disease (COPD) and healthy individuals on the Continuous Scale Physical Functional Performance 10 (PFP10) test and, second, to test the reproducibility of the PFP10 test in these participants.

METHODS

In a prospective, cross-sectional study, 28 patients with COPD (67 ± 9 y, FEV1: 44.3 ± 16.9% pred) and 12 healthy volunteers (healthy group) matched by age, body mass index, and sex were included. The participants performed 2 PFP10 tests 5 d apart. Main outcome measure was performance on the PFP10 test and included total score, score for specific domains, and total time to perform the PFP10 test.

RESULTS

The functional performance of patients with COPD was worse than that of the healthy group on PFP10 total scores (43.9 ± 12.6 vs 63.5 ± 9.4, respectively; P < .001; effect size: 1.78) and time to complete the tasks (207.9 ± 36.1 sec vs 153.2 ± 12.1 sec, respectively; P < .001, effect size: 2.27). In addition, the COPD group had significantly worse performance in the domains of upper-body strength, lower-body strength, balance and coordination, and endurance. The test was highly reproducible (ICC: 0.98; 95% CI, 0.96-0.99 for both groups), and the mean difference (upper and lower limits of agreement) of the total scores was -3 (-9 to 3).

CONCLUSIONS

The PFP10 test is a suitable and reproducible test for determining decreases in the functional performance of patients with COPD compared with healthy individuals.