Association between peripheral muscle strength, exercise performance, and physical activity in daily life in patients with Chronic Obstructive Pulmonary Disease

Associations of Upper-Extremity Exercise Capacity and Grip Strength With Cognitive Domains in Patients With COPD

BACKGROUND

Cognitive impairment (CI), which has been reported in COPD, has been related to physical performance. However, the association between CI and upper-extremity functions is unknown. We aimed to compare upper-extremity exercise capacity and grip strength between subjects with COPD with and without CI and to determine the relationship of upper-extremity functions with specific cognitive domains.

METHODS

In this cross-sectional study, 76 subjects with COPD (mean age 66.8 ± 7.5 y, FEV1% 47.12 ± 14.10) were classified as with and without CI according to the Montreal Cognitive Assessment. Clinical characteristics, upper-extremity exercise capacity (6-min pegboard ring test [6PBRT]), grip strength (hand dynamometer), dyspnea severity (modified Medical Research Council dyspnea scale), disease-specific health status (COPD Assessment Test), and disease-specific quality of life (St George Respiratory Questionnaire) were compared between groups, and the relationship of upper-extremity functions with cognitive subdomains was analyzed by multivariate regression analysis.

RESULTS

The number of 6PBRT rings (P = .01) and the grip strength (P = .033) were lower in subjects with CI. Subjects with CI had lower FEV1% (P = .038), arterial oxygenation (P = .002), exercise habits (P = .033), health status (P = .01), quality of life (P = .042); and higher dyspnea (P < .001), smoking consumption (P = .032), emergency admission (P = .02), and hospitalization (P = .042). The adjusted model showed that executive functions and attention were related to upper-extremity capacity (β = 14.4 and β = 10.2, respectively) and hand-grip strength (β = 1.85 and β = 1.49, respectively).

CONCLUSIONS

These findings suggest that upper-extremity functions might be decreased especially concerning executive functions and attention in subjects with COPD with CI.

Exercise Performance and Quality of Life of Left Ventricular Assist Device Patients After Long-Term Outpatient Cardiac Rehabilitation

PURPOSE

Exercise performance and quality of life (QoL) of left ventricular assist device (LVAD) patients improve after early cardiac rehabilitation (CR). The purpose of this study was to examine the efficacy of multiprofessional long term phase 3 outpatient CR, and whether cardiopulmonary exercise testing (CPX) and 6-min walk testing (6MWT) post-LVAD implantation predict hospital readmission.

METHODS

This retrospective observational cohort study included 29 LVAD patients (58.6 ± 7.7 yr, female: 13.8%, body mass index: 29.4 ± 3.3 kg/m 2 ). Functional performance tests (CPX, 6MWT, sit-to-stand test), QoL, and psychological surveys (Kansas City Cardiomyopathy Questionnaire, hospital anxiety and depression scale, and Control Convictions about Disease and Health [KKG]) were performed at baseline and at the end of CR.

RESULTS

The CR was initiated at a median (IQR) of 159 (130-260) d after LVAD implantation for a duration of 340 (180-363) d with 46.8 ± 23.2 trainings. The 6MWT (408.4 ± 113.3 vs 455.4 ± 115.5 m, P = .003) and sit-to-stand test (16.7 ± 6.9 vs 19.0 ± 5.3 repetitions, P = .033) improved, but relative peak oxygen uptake (V˙ o2peak : 9.4 [8.2-14.4] vs 9.3 [7.8-13.4] mL/min/kg, P = .57) did not change. Using receiver operating characteristic curve analysis, baseline V˙ o2peak values were associated with readmission 1-yr after CR onset (C-statistic = 0.88) with a cutoff value of V˙ o2peak < 9.15 mL/min/kg (100% sensitivity, 78% specificity, P < .001). The Kansas City Cardiomyopathy Questionnaire self-efficacy and knowledge (+6.3 points), QoL (+5.0 points), and social limitation (+7.1 points) demonstrated clinically important changes. In addition, the hospital anxiety and depression scale showed a significant reduction in anxiety (4.6 ± 3.2 vs 2.6 ± 2.4, P = .03).

CONCLUSIONS

Long-term CR is safe and LVAD outpatients showed improvement of QoL, anxiety, and submaximal exercise performance. In addition, V˙ o2peak and 6MWT have prognostic value for readmission.

Pulmonary Hypertension and Measurement of Exercise Capacity Remotely: Evaluation of the 1-min Sit-to-Stand Test (PERSPIRE) - a cohort study

Background

Multiparameter risk assessment is recommended to aid treatment decisions in patients with pulmonary arterial hypertension. The 1-min sit-to-stand test (1MSTS) has been validated for use in other respiratory illnesses. The aim of this study was to evaluate its safety in the hospital setting and potential utility in remote assessment in patients with pulmonary hypertension.

Methods

In a prospective cohort study design patients performed the 1MSTS and incremental shuttle walk test (ISWT) on the same day. The primary aim of the study was to assess safety signals and correlations with other metrics used in risk assessment.

Results

60 patients with pulmonary arterial hypertension and 15 with chronic thromboembolic pulmonary hypertension were enrolled. No adverse events were recorded. Post-test change in physiological parameters was lower for the 1MSTS than for the ISWT in heart rate (mean±sd change +9.4±8.0 versus +38.3±25.9 beats per min, p<0.001), oxygen saturation (-3.8±4.0% versus -8.9±7.3%, p<0.01) and systolic blood pressure (+10.1±10.5 versus +17.7±19 mmHg, p<0.001). There were significant correlations between the 1MSTS and ISWT (r=0.702, p<0.01), World Health Organization functional class (r= -0.449, p<0.01), emPHAsis-10 (-0.436, p<0.001) and N-terminal pro-b-type natriuretic peptide (r= -0.270, p=0.022). 97% of patients were willing to perform the test at home.

Conclusion

This study has demonstrated the safety, sub-maximal characteristics of the 1MSTS in pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension in the hospital setting, its positive correlation with the ISWT and potential role in remote risk assessment. Further evaluation of this exercise test is now warranted.

Acute effects of NIV on peripheral muscle function and aerobic performance in patients with chronic obstructive pulmonary disease: a pilot study

Background

Non-invasive ventilation (NIV) reduces respiratory load and demands on peripheral muscles.

Methods

This study aims to evaluate the acute effects of bi-level NIV on peripheral muscle function during isokinetic exercise and aerobic performance in chronic obstructive pulmonary disease (COPD) patients. This is a pilot crossover study performed with a non-probabilistic sample of 14 moderate to very severe COPD patients. Procedures carried out in two days. Dyspnea, quality of life, lung function, respiratory muscle strength, functional capacity (6-min walk test—6MWT), and isokinetic assessment of the quadriceps were assessed. Blood samples (lactate, lactate dehydrogenase, and creatine kinase concentration) were also collected. Right after, NIV was performed for 30 min (bi-level or placebo, according to randomization) followed by new blood sample collection, 6MWT, and isokinetic dynamometer tests. Before and after evaluations, the subjective perception of dyspnea and fatigue in the lower limbs was quantified. After a wash-out period of seven days, participants returned, and all assessments were performed again.

Results

NIV showed improvements in perceived exertion and dyspnea after isokinetic exercise (p < 0.02 and p < 0.05, respectively).

Conclusions

NIV improves the perception of dyspnea and fatigue during the isokinetic exercise.

Association between Sleep Duration and Hand Grip Strength among COPD Patients

This study aimed to evaluate the association between night-time sleep duration and hand grip strength (HGS) among patients with chronic obstructive pulmonary disease (COPD). Participants aged ≥45 years were included in a nationally representative investigation clinical study in 2015. HGS was measured using dynamometers. The data on night-time sleep duration, sociodemographic information, and health-related variables were systematically collected. For analysis, sleep duration was categorized as <5 h, 5-7 h, 7 h, 7-9 h, and >9 h. Multivariable linear regression models were used to determine the possible association between the night-time sleep duration and HGS. Our results indicated that the shortest (<5 h) or the longest sleep duration (>9 h) was relevant to high risk of weaker HGS in females. In males, the shortest (<5 h) sleep duration was correlated to lower HGS. Thus, our findings clearly suggest that health care providers should focus on the potential influence of sleep duration on HGS among COPD patients.

Muscle function and functional performance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a prospective observational study

This study aimed to measure changes in different properties of skeletal muscles and evaluate their contribution and relationship to changes in functional performance after pulmonary rehabilitation (PR) in patients with chronic obstructive pulmonary disease (COPD). COPD outpatients attending 5 weeks of conventional PR were recruited. Functional performance [5-repetitions sit-to-stand (5STS), and 4-m gait speed (4mGS)], and muscle function (maximal isometric strength, power, force control, and relative concentric and eccentric activation during 5STS) were assessed after PR and 3 months of follow-up. Twenty patients (71 years; 52% of predicted FEV₁) completed the study. 4mGS and relative concentric activation during 5STS decreased respectively by 7.7% and 26% between the beginning of PR and follow-up. Quadriceps strength, power, and force control improved by 10.4%, 27.3%, and 15.2%, respectively, from the beginning of PR to follow-up the relative eccentric activation during 5STS explained 31% of the variance in 4mGS changes. In conclusion, functional performance appeared to decline after conventional PR, whereas several properties of skeletal muscles were maintained at follow-up in COPD outpatients. Of note, eccentric contractions might play a role in the improvement of functional performance. Therefore, future studies with interventional design should include eccentric training in PR programs during clinical COPD practice.

Impact of resistance training on the 6-minute walk test in individuals with chronic obstructive pulmonary disease: A systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review was to assess functional improvement, measured by the 6-minute walk test (6MWT) after the application of a resistance training (RT) protocol in people with chronic obstructive pulmonary disease (COPD).

MATERIALS AND METHODS

The search involved the databases ClinicalTrials.gov, Cochrane Central Register of Controlled Trials, EMBASE, PubMed and Scopus from the beginning of inception to September 1, 2019. Randomized controlled trials evaluating the functional impact of RT were included. The quality of the trials was assessed with the Physiotherapy Evidence Database (PEDro) scale. Calculations were performed according to mean difference (MD) for differences between pre- and post-intervention in 6MWT distance and according to the standardized mean difference (SMD) for post-treatment results of the 6MWT and quadriceps muscle strength (QMS) improvement.

RESULTS

In total, 23 studies (690 patients) met the inclusion criteria. Meta-analysis was used to compute the best improvement on the 6MWT with an analysis of improvement pre- versus post-treatment (MD 37.3, 95% confidence interval [CI] 9.8; 64.8, I² = 86%, p = 0.008) versus post-treatment alone, intervention versus control group (MD 15.5, 95% CI -7.7; 38.6, I^2 = 71%, p = 0.19). QMS was significantly improved (SMD 2.9, 95% CI 1.1; 4.7, I^2 = 91%, p = 0.002).

CONCLUSION

The results of the meta-analysis show a significant improvement in walking ability and performance measured by the 6MWT and an improvement in QMS for people with COPD responding to the therapy. The main limitation of this review is the significant heterogeneity across the study results. Furthermore, the statistical significance does not totally coincide with the clinical significance. RT is recommended to reduce muscle dysfunction and seems useful when combined with endurance training.

Prediction of Sarcopenia Using Multiple Biomarkers of Neuromuscular Junction Degeneration in Chronic Obstructive Pulmonary Disease

Patients with chronic obstructive pulmonary disease (COPD) present with an advanced form of age-related muscle loss or sarcopenia. Among multiple pathomechanisms of sarcopenia, neuromuscular junction (NMJ) degradation may be of primary relevance. We evaluated the circulating biomarkers of NMJ degradation, including c-terminal agrin fragment -22 (CAF22), brain-derived neurotrophic factor (BDNF), and glial cell line-derived neurotrophic factor (GDNF) as predictors of sarcopenia in COPD during pulmonary rehabilitation (PR). Male, 61-77-year-old healthy controls and patients of COPD (n = 77-84/group) were recruited for measurements of circulating CAF22, BDNF, and GDNF levels. Functional assessment and measurements of plasma biomarkers were performed at diagnosis and following six months of PR. CAF22 levels were elevated while BDNF and GDNF levels were reduced in COPD patients at diagnosis, which were incompletely restored to normal levels following PR. These biomarkers showed varying degrees of associations with indexes of sarcopenia and functional recovery during PR. Logistic regression revealed that the combined use of three biomarkers enhanced the diagnostic accuracy of sarcopenia better than single biomarkers. Altogether, measurements of plasma CAF22, BDNF, and GDNF may be helpful for the accurate diagnosis of sarcopenia and functional capacity in COPD during PR.

The correlation between quadriceps muscle strength and endurance and exercise performance in patients with COPD

To determine the association between quadriceps muscle strength (QMS) and endurance (QME) and exercise capacity in patients with COPD after stratification for sex and resting lung function (LF). Data were collected from 3,246 patients with COPD (60% men, 64 ± 9 yr), including measures of exercise capacity [peak aerobic capacity (peakV̇o₂), 6-min walk distance (6MWD)] and isokinetic QMS and QME. Patients were stratified for sex, forced expiratory volume in 1 s (>50/≤50% predicted), single breath carbon monoxide diffusing capacity (>50/≤50% predicted), and residual volume (>140/≤140% predicted). After stratification for resting LF, QMS and QME were significantly associated with peakV̇o₂ (r range: 0.47-0.61 and 0.49-0.65 for men and 0.53-0.66 and 0.48-0.67 for women, respectively) and 6MWD (r range: 0.29-0.42 and 0.44-0.55 for men and 0.25-0.54 and 0.34-0.55 for women, respectively) (P < 0.001). Regression models demonstrated that QMS and QME were significant determinants of peakV̇o₂ (explained variance R² range: 35.6%-48.8% for men and 36.8%-49.0% for women) and 6MWD (R² range: 24.3%-43.3% for men and 28.4%-40.3% for women), independent of age and fat-free mass. Quadriceps muscle function was significantly associated with peakV̇o₂ and 6MWD in male and female patients with COPD after stratification for resting LF, in which QME appear to be a more important determinant than QMS. This underlines the importance of systematically evaluating both quadriceps muscle strength and endurance in in all patients with COPD.NEW & NOTEWORTHY Our findings identified quadriceps muscle function as an important determinant of exercise capacity across a wide spectrum of lung function. Quadriceps muscle endurance appears to be a more important determinant than quadriceps muscle strength, underlining the importance of including both the measurement of quadriceps muscle strength and endurance in routine assessment for all patient with COPD.

Isotonic quadriceps endurance is better associated with daily physical activity than quadriceps strength and power in COPD: an international multicentre cross-sectional trial

Knowledge about modifiable determinants of daily physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) is crucial to design effective PA interventions. The present study aimed to determine the contribution of quadriceps strength, power and endurance to daily PA in COPD. Additionally, for quadriceps endurance, we also aimed to determine to what extent the association varies according to the mode of movement (isotonic, isometric, or isokinetic). Using a multicentre cross-sectional trial design we determined the contribution of quadriceps function to daily PA (steps, sedentary time and time spent doing moderate-to-very-vigorous physical activity [MVPA]) using bivariate and partial Pearson correlation analysis (r) and multiple linear regression models (ΔR²). Pre-determined controlling factors were sex, age, body mass index (BMI), COPD-assessment test, forced expiratory volume in one second in percent of the predicted value (FEV_1pred), and distance walked on the 6-minute walk test. Eighty-one patients with COPD (mean ± SD: age 67 ± 8 years, FEV_1pred 57 ± 19%, daily steps 4968 ± 3319, daily sedentary time 1016 ± 305 min, and MVPA time 83 ± 45 min) were included. Small to moderate bivariate correlations (r = .225 to .452, p < .05) were found between quadriceps function and measures of PA. The best multiple linear regression models explained 38–49% of the variance in the data. Isotonic endurance was the only muscle contributor that improved all PA models; daily steps (ΔR² = .04 [relative improvement 13%] p = .026), daily sedentary time (ΔR² = .07 [23%], p = .005) and MVPA-minutes (ΔR² = .08 [20%], p = .001). Isotonic endurance was also independently associated with most PA variables, even when controlling for strength, power or isometric-isokinetic endurance properties of the muscle (r = .246 to .384, p < .05). In contrast, neither strength, power, isometric-or isokinetic endurance properties of the muscle was independently associated with PA measures when controlling for isotonic endurance (r = .037 to .219, p > .05). To conclude, strength, power, and endurance properties of the quadriceps were low to moderately associated with PA in patients with COPD. Isotonic quadriceps endurance was the only quadriceps property that was independently associated with the different measures of PA after controlling for a basic set of known determinants of PA, quadriceps strength or power, or isometric or isokinetic quadriceps endurance. Future longitudinal studies should investigate its potential as a modifiable determinant of PA.

Specific Contribution of Quadriceps Muscle Strength, Endurance, and Power to Functional Exercise Capacity in People With Chronic Obstructive Pulmonary Disease: A Multicenter Study

OBJECTIVE

Various functional muscle properties affect different aspects of functional exercise capacity in people with chronic obstructive pulmonary disease (COPD). The purpose of this study was to investigate the contribution of quadriceps muscle strength, endurance, and power to 6-Minute Walking Distance (6MWD) and 1-minute sit-to-stand test (1STS) performance in people with COPD.

METHODS

The study was a prospective, multicenter, cross-sectional study. Anthropometrics, Medical Research Council dyspnea scale, lung function, 6MWD, and 1STS number of repetitions were assessed. Isometric quadriceps strength and endurance, isotonic quadriceps endurance, isokinetic quadriceps strength, and power were assessed on a computerized dynamometer while functional quadriceps power was determined during 5 sit-to-stand repetitions. Univariate and multivariate analyses were performed to determine the contribution of functional muscle properties to the 6MWD and the 1STS number of repetitions.

RESULTS

The study included 70 people with COPD (mean % predicted forced expiratory volume in 1 second = 58.9 [SD = 18.2]). The 6MWD correlated with each functional muscle property except the isometric quadriceps endurance. The number of repetitions during the 1STS correlated with each functional muscle property except isometric measurements. Multivariate models explained 60% and 39% of the variance in the 6MWD and 1STS number of repetitions, respectively, with quadriceps power determined during 5 sit-to-stand repetitions being the muscle functional property with the strongest contribution to the models.

CONCLUSION

Except for isometric endurance, quadriceps strength, endurance, and power were associated with functional exercise capacity in people with moderate COPD. Among these functional muscle properties, muscle power contributed the most to the 6MWD and 1STS number of repetitions, suggesting that muscle power is more relevant to functional exercise capacity than muscle strength or endurance in people with COPD.

IMPACT

Understanding the individual contribution of muscle properties to functional status is important to designing interventions. This study provides the guidance that muscle power may be more important to functional exercise capacity than muscle strength or endurance in people with COPD.

The association of objectively measured physical activity and sedentary behavior with skeletal muscle strength and muscle power in older adults: A systematic review and meta-analysis

BACKGROUND

Engaging in physical activity (PA) and avoiding sedentary behavior (SB) are important for healthy ageing with benefits including the mitigation of disability and mortality. Whether benefits extend to key determinants of disability and mortality, namely muscle strength and muscle power, is unclear.

AIMS

This systematic review aimed to describe the association of objective measures of PA and SB with measures of skeletal muscle strength and muscle power in community-dwelling older adults.

METHODS

Six databases were searched from their inception to June 21^st, 2020 for articles reporting associations between objectively measured PA and SB and upper body or lower body muscle strength or muscle power in community dwelling adults aged 60 years and older. An overview of associations was visualized by effect direction heat maps, standardized effect sizes were estimated with albatross plots and summarized in box plots. Articles reporting adjusted standardized regression coefficients (β) were included in meta-analyses.

RESULTS

A total of 112 articles were included representing 43,796 individuals (range: 21 to 3726 per article) with a mean or median age from 61.0 to 88.0 years (mean 56.4 % female). Higher PA measures and lower SB were associated with better upper body muscle strength (hand grip strength), upper body muscle power (arm curl), lower body muscle strength, and lower body muscle power (chair stand test). Median standardized effect sizes were consistently larger for measures of PA and SB with lower compared to upper body muscle strength and muscle power. The meta-analyses of adjusted β coefficients confirmed the associations between total PA (TPA), moderate-to-vigorous PA (MVPA) and light PA (LPA) with hand grip strength (β = 0.041, β = 0.057, and β = 0.070, respectively, all p ≤ 0.001), and TPA and MVPA with chair stand test (β = 0.199 and β = 0.211, respectively, all p ≤ 0.001).

CONCLUSIONS

Higher PA and lower SB are associated with greater skeletal muscle strength and muscle power, particularly with the chair stand test.

[Which physical tests for which objectives in pulmonary rehabilitation?]

Chronic respiratory disease is a major cause of morbidity and mortality worldwide and an important cause of disability including a reduction of exercise, functional and muscle capacity contributing to a decreased quality of life. In the context of pulmonary rehabilitation, a thorough patient-centered outcome assessment, including not only measures of lung function, but also exercise functional and muscle capacity, is imperative for a comprehensive disease management. Assessment of these impairments and dysfunctions with appropriate and change-sensitive procedures is thus necessary for personalizing the physical interventions and assessing the short- and long-term effectiveness of the intervention. The clinician currently has a wide variety of tests and measurements available to assess the physical and functional capacity of people with chronic respiratory disease. The aim of this review is to provide a pragmatic synthesis of the physical, functional and muscle capacity tests most commonly used in pulmonary rehabilitation. Ultimately, it should help the clinician to identify the relevant evaluations according to the objectives of the patients but also according to the available resources, the setting of pulmonary rehabilitation and the specific qualities of each test.

Cardiorespiratory Response during the 1-min Sit-to-Stand Test in Chronic Obstructive Pulmonary Disease

PURPOSE

This study aimed to assess the cardiorespiratory response during a 1-min sit-to-stand test (1STS) in comparison with cycling cardiopulmonary exercise test (CPET) in people with chronic obstructive pulmonary disease (COPD) and in healthy subjects and to evaluate whether 1STS may induce leg fatigue in these individuals.

METHODS

Fourteen people with severe COPD and 12 healthy subjects performed a 1STS and a CPET during which cardiorespiratory response, perception of dyspnea, and leg fatigue were assessed. Quadriceps strength was assessed before and after 1STS, and contractile fatigue was defined as a postexercise fall in quadriceps twitch force greater than 15% of resting values.

RESULTS

In COPD, peak V˙O2, V˙E, and HR achieved during 1STS reached 113%, 103%, and 93% of the corresponding values during CPET, respectively. Decrease in SpO2 from preexercise to peak exercise and the magnitude of dynamic hyperinflation were similar between 1STS and CPET. Borg dyspnea and leg fatigue scores were higher for CPET than 1STS. In healthy subjects, peak cardiorespiratory demand and symptom scores were higher during CPET compared with 1STS. A V˙O2 overshoot during recovery was observed only in people with COPD. After 1STS, the V˙O2 half-time recovery of COPD was 152 ± 25 s compared with 74 ± 18 in healthy subjects (P < 0.01). Ten people with COPD and five healthy subjects were considered as fatiguers.

CONCLUSION

The 1STS induced a similar cardiorespiratory stress to that of CPET and was associated with contractile quadriceps fatigue in people with severe COPD. The V˙O2 overshoot and slower recovery time of cardiorespiratory variables seen in COPD demonstrate the clinical relevance of monitoring the recovery phase of exercise.

Easy to Perform Physical Performance Tests to Identify COPD Patients with Low Physical Activity in Clinical Practice

Background

The study investigates which physical performance or muscle function/mass tests significantly correlate with objectively measured physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) and could potentially serve to identify physically inactive COPD patients in routine clinical practice.

Methods

A cross-sectional, observational study was conducted in outpatients with moderate to very severe COPD. PA was measured during one week with the StepWatch Activity Monitor^®, an ankle-worn accelerometer, and expressed in steps per day. Physical fitness and peripheral muscle function/mass were evaluated by the 4-meter gait speed (4MGS) test, the 6-minute walk distance (6MWD), the 30-second chair stand test (30sCST), the timed up and go test (TUGT), handgrip strength, arm muscle area, calf circumference, the fat-free mass index (FFMI), and ultrasound measurement of the quadriceps muscle. Spearman’s rank correlation analysis and ROC analysis were performed.

Results

The study population (N=111, 69% men, mean age 68 years) walked a mean of 8059 steps/day. The daily step count strongly correlated with the 6MWD (rho=0.684, p<0.001) and moderately with the 4MGS (rho=0.464, p<0.001), the TUGT (rho= −0.463, p<0.001), and the 30sCST (rho=0.402, p<0.001). The correlation with the FFMI was weak (rho=0.210, p=0.027), while the other parameters did not significantly correlate with the daily step count. The 6MWD had the best discriminative power to identify patients with very low PA defined as <5000 steps/day (AUC=0.802 [95% CI: 0.720–0.884], p<0.001), followed by the TUGT, the 4MGS, and the 30sCST.

Conclusion

The 6MWD, the 4MGS, the TUGT, and the 30sCST are easy to perform in any clinical setting and may be used by clinicians in the screening of physically inactive COPD patients.

Stability and Predictors of Poor 6-min Walking Test Performance over 2 Years in Patients with COPD

Poor performance in the 6-min walk test (6MWT < 350 m) is an important prognostic indicator of mortality and risk of exacerbations in patients with chronic obstructive pulmonary disease (COPD). Little is known about the stability of this state over time and what factors might predict a poor 6MWT performance. To determine the stability of 6MWT performance over a 2-year period in COPD patients participating in annual medical follow-up visits, and to assess the ability of several clinical, pulmonary, and non-pulmonary factors to predict poor 6MWT performance, we prospectively included 137 patients with stable COPD (mean age, 66.9 ± 8.3 years). The 6MWT was scored at baseline and 2-year follow-up. To evaluate clinical, pulmonary, and non-pulmonary variables as potential predictors of poor 6MWT performance, we used multiple logistic regression models adjusted for age, sex, weight, height, and 6MWT performance at baseline. Poor 6MWT performance was stable over 2 years for 67.4% of patients. Predictors of poor 6MWT performance included a five-repetition sit-to-stand test score ≤2 (OR, 3.01; 95% CI, 1.22-7.42), the percentage of mobility activities with limitations (OR, 1.03; 95% CI, 1.00-1.07), and poor 6MWT performance at baseline (OR, 4.64; 95% CI, 1.88-11.43). Poor 6MWT performance status was stable for the majority of COPD patients. Lower scores on the five-repetition sit-to-stand test and a higher number of mobility activities with limitations were relevant predictors of poor 6MWT performance over 2 years. Prognostic models based on these non-pulmonary factors can provide non-inferior discriminative ability in comparison with prognostic models based on only pulmonary factors.

Cardiopulmonary Endurance of Hospitalized Older Adults With Chronic Obstructive Pulmonary Disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) could lead to poor cardiopulmonary endurance, which affects quality of life and increases the risk of rehospitalization or mortality. However, studies investigating associated factors of cardiopulmonary endurance for COPD inpatients are scant.

OBJECTIVE

The aim of the study was to investigate whether and how age, gender, COPD severity, body composition, dyspnea, respiratory muscle strength, and lower limb muscle strength and endurance were related to cardiopulmonary endurance in elderly inpatients with COPD.

METHODS

This was a cross-sectional study using a systematic sampling of older inpatients. Data of demographic characteristics such as age, gender, and disease severity were collected, and body mass index was calculated. Degrees of dyspnea were assessed by the modified Medical Research Council Dyspnea Scale. Respiratory muscle strength was reflected by the maximal inspiratory pressure and the maximal expiratory pressure. Lower limb muscle strength and endurance were assessed by a handheld dynamometer and a 30-second sit-to-stand test, respectively. Finally, cardiopulmonary endurance was assessed by a 6-minute walk test.

RESULTS

A total of 83 older COPD inpatients participated. The mean age was 74.01 ± 6.93 years. Cardiopulmonary endurance was associated with age, COPD severity, dyspnea, respiratory muscle strength, lower limb muscle strength, and endurance. Predictors of cardiopulmonary endurance were disease severity, dyspnea, and lower limb muscle endurance. These predictors explained 53% of the variance in cardiopulmonary endurance in older inpatients with COPD.

DISCUSSION

Cardiopulmonary endurance of hospitalized older adults with COPD should be strengthened by improving conditions of disease severity, dyspnea, and lower limb muscle endurance.

Maximal handgrip strength can predict maximal physical performance in patients with chronic fatigue

BACKGROUND

Maximal handgrip strength is used to predict exercise performance in healthy older subjects and in patients with chronic obstructive pulmonary disease, breast cancer or cirrhosis. Our objective was to evaluate the ability of maximal handgrip strength to predict maximal exercise performance in patients with chronic fatigue.

METHODS

Sixty-six patients with myalgic encephalomyelitis/chronic fatigue syndrome and 32 patients with chronic fatigue but no diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome were included. The maximal physical performance was measured on a cycle ergometer to measure the peak oxygen uptake and the maximal work rate. We searched for linear regressions between maximal handgrip strength and maximal performances.

FINDINGS

No significant differences in slopes and ordinates of regression lines were noted between patients with or without a diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome, allowing to pool the data. Maximal handgrip strength was significantly and positively correlated with peak oxygen uptake and maximal work rate in all patients with chronic fatigue.

INTERPRETATION

We conclude that handgrip strength can predict maximal exercise performance in patients with chronic fatigue.

Physiological response to the Glittre-ADL test in elderly COPD patients

Abstract Introduction: The Glittre-ADL (TGlittre) test was developed to assess functional capacity in a group of activities of daily living, but little is known about the physiological responses expected during its implementation. Objective: To evaluate the physiological responses induced by TGlittre in COPD patients and compare them with those induced by the 6-minute walk test (6MWT). Method: This is a cross-sectional study involving 15 elderly patients with COPD (70±6 years and predicted FEV1 of 47±16%). The TGlittre and 6MWT were performed on two different days, evaluating heart rate, peripheral oxygen saturation and perceived exertion in the 1st, 4th and 6th minutes of the 6MWT and at the start, after each lap and the end of TGlittre. After the normality test (Shapiro-Wilk), the Wilcoxon test was applied to compare the functional tests, and Spearman’s correlation coefficient to assess the association between variables. Results: At the end of TGlittre, heart rate was faster than in the 6MWT (106.7±21.9 vs 96.4±16.2bpm, p = 0.02). The other physiological variables were similar at the end of both tests. Heart rate at the end of TGlittre correlated with the final heart rate in the 6MWT (r = 0.69; p = 0.002). Conclusion: TGlittre induced a faster heart rate than in the 6MWT, with increased metabolic demand, but with similar ventilatory responses.

Measuring and monitoring skeletal muscle function in COPD: current perspectives

Skeletal muscle dysfunction is an important systemic consequence of chronic obstructive pulmonary disease (COPD) that worsens the natural cause of the disease. Up to a third of all people with COPD express some form of impairment which encompasses reductions in strength and endurance, as well as an increased fatigability. Considering this complexity, no single test could be used to measure and monitor all aspects of the impaired skeletal muscle function within the COPD population, resulting in a wide range of available tests and measurement techniques. The aim of the current review is to highlight current and new perspectives relevant to skeletal muscle function measurements within the COPD population in order to provide guidance for researchers as well as for clinicians. First of all, standardized and clinically feasible measurement protocols, as well as normative values and predictive equations across the spectrum of impaired function in COPD, are needed before assessment of skeletal muscle function can become a reality in clinical praxis. This should minimally target the quadriceps muscle; however, depending on the objective of measurements, eg, to determine upper limb muscle function or walking capacity, other muscles could also be tested. Furthermore, even though muscle strength measurements are important, current evidence suggests that other aspects, such as the endurance and power capacity of the muscle, should also be considered. Moreover, although static (isometric) measurements have been favored, dynamic measurements of skeletal muscle function should not be neglected as they, in a larger extent than static measurements, are related to tasks of daily living. Lastly, the often modest relationships between functional tests and skeletal muscle function measurements indicate that they evaluate different constructs and thus cannot replace one another. Therefore, for accurate measurements of skeletal muscle function in people with COPD, specific and formal measurements should still be prioritized.

The six-minute stepper test is related to muscle strength but cannot substitute for the one repetition maximum to prescribe strength training in patients with COPD

Purpose

There are many barriers to pulmonary rehabilitation, including a limited access to evaluation centers. To cope with these difficulties, field tests are often used to prescribe endurance training. As field tests are related to muscle strength, they could also be used to prescribe strength training and increase the access to pulmonary rehabilitation in rural area. However, their validity for this purpose has never been studied.

Patients and methods

The relationship between the 6-minute stepper test (6MST), 6-minute walk test, maximal workload achieved during cardiopulmonary exercise testing (Wpeak), and one repetition maximum (1RM) was assessed in 35 patients with COPD through a retrospective chart review to derive predictive equation of the 1RM from these tests. The effectiveness of these equations to prescribe strength training at 70% of the 1RM was assessed in an independent cross-validation group of 34 patients with COPD.

Results

There was a moderate relationship between the 6MST, Wpeak and the 1RM (r=0.44 and r=0.41, respectively, both P≤0.01). Whatever the test, the prescription of strength training using the estimated 1RM compared with the measured 1RM resulted in a mean absolute difference and a mean bias of about 30 kg.

Conclusion

The use of the 6MST and Wpeak for the prescription of strength training would result in a clinically not acceptable error. Therefore, they should not be used as a substitute for the 1RM to prescribe strength training.

1-Minute Sit-to-Stand Test: SYSTEMATIC REVIEW OF PROCEDURES, PERFORMANCE, AND CLINIMETRIC PROPERTIES

PURPOSE

Tests for quantifying exercise capacity that are applicable in diverse settings are needed. The 1-min sit-to-stand test (1-MSTST) is such a test. This systematic review summarizes the literature addressing 1-MSTST procedures, performance, and clinimetric properties.

METHODS

Three online databases, hand searches, and an expert consultant were used to identify literature relevant to the aims of this review. Inclusion required that studies addressed the 1-MSTST, focused on adults, and were written in English.

RESULTS

Seventeen articles were identified that met the inclusion criteria. The populations assessed included adults without identified pathologies and adults with lung disease, renal disease, stroke, osteoporosis, or receiving palliative care. The 1-MSTST typically involves an armless chair and the performance of as many sit-to-stand actions as possible in 1 min without using the upper limbs. The mean number of 1-MSTST repetitions reported in the literature achieved ranged from 8.1 (patients with stroke) to 50.0 (young men). Numerous studies supported the convergent and known-groups validity and the test-retest reliability of the test. The test has been shown to be responsive. Normative reference values are available.

CONCLUSIONS

The literature provides considerable support for using the 1-MSTST to quantify exercise capacity. Broader use of this test may be indicated, particularly where space and time are limited.

Does peripheral arterial occlusive disease influence muscle strength and exercise capacity in COPD patients?

Background

The pathophysiology of chronic obstructive pulmonary disease (COPD) is complex and understanding of it has been changing in recent years, with regard to its multisystemic manifestations, especially peripheral dysfunction and its influence on intolerance to exercise.

Objectives

To evaluate the relationship between peripheral arterial occlusive disease (PAOD) and peripheral muscle strength and exercise capacity in COPD patients.

Methods

We conducted a cross-sectional study of 35 patients with COPD who were evaluated with the Ankle-Brachial Index, handgrip strength test, 1 repetition maximum (1RM) of knee extensors and flexors, and distance covered in the incremental shuttle walking test (dISWT).

Results

COPD patients with coexisting PAOD had lower dominant handgrip strength test results (33.00 vs. 26.66 kgf, p = 0.02) and worse performance in the dISWT (297.32 vs. 219.41 m, p = 0.02) when compared to the COPD patients without PAOD. Strong correlations were found between the result of the handgrip strength test and both the dISWT (r = 0.78; p < 0.001) and the 1RM/knee extension (r = 0.71; p = 0.03); and also between the dISWT and both the 1RM/knee extension (r = 0.72; p = 0.02) and the 1RM/knee flexion (r = 0.92; p < 0.001). The linear regression model showed that the dISWT variable alone explains 15.3% of the Ankle-Brachial Index result (p = 0.01).

Conclusion

COPD patients with PAOD exhibit reduced muscle strength and lower exercise capacity than COPD patients without PAOD.

Handgrip and functional capacity in Chronic Obstructive Pulmonary Disease patients

Abstract Introduction: In the Chronic Obstructive Pulmonary Disease (COPD) both pulmonary and systemic condition increase dyspnea, intolerance to exercise and inactivity. Objective: To evaluate possible association between Hand Grip Strength (HGS) and the distance covered in the Six-Minute Walk Test (6MWT) in patients with Chronic Obstructive Pulmonary Disease (COPD). Methods: A cross-sectional study that evaluated 34 patients with COPD from moderate to very severe stages. The HGS test was performed with a manual hydraulic dynamometer (Jamar®, California, USA) with three bilateral measures, allowing 60-seconds rest time in-between measurements. Afterwards, the patients were submitted to the 6MWT along a 30-meters level corridor following the rules of the American Thoracic Society. Results: Average age 62.7±7.2 years old, body mass index 26.7±6.9 Kg/m². The value of the HGS in the dominant hand was 28.0±8.7 Kgf and in the non-dominant hand was 26.7±7.7 Kgf (99.2% of the predicted value and 106.3% of the predicted value, respectively). The subjects covered in average 421.0±110.4 meters in the 6MWT and there has been detected direct and significant correlation between the distance covered and the HGS of the dominant hand (r=0,430; p=0,011) and non-dominant (r=0,502; p=0,002). The patients with COPD that presented lower HGS also covered less distance in the 6MWT. Conclusion: The hand grip strength was directly associated with the functional capacity assessed through the distance covered in the Six-Minute Walk Test in the evaluated trial.

A multicentre validation of the 1-min sit-to-stand test in patients with COPD

Our aim was to comprehensively validate the 1-min sit-to-stand (STS) test in chronic obstructive pulmonary disease (COPD) patients and explore the physiological response to the test.We used data from two longitudinal studies of COPD patients who completed inpatient pulmonary rehabilitation programmes. We collected 1-min STS test, 6-min walk test (6MWT), health-related quality of life, dyspnoea and exercise cardiorespiratory data at admission and discharge. We assessed the learning effect, test-retest reliability, construct validity, responsiveness and minimal important difference of the 1-min STS test.In both studies (n=52 and n=203) the 1-min STS test was strongly correlated with the 6MWT at admission (r=0.59 and 0.64, respectively) and discharge (r=0.67 and 0.68, respectively). Intraclass correlation coefficients (95% CI) between 1-min STS tests were 0.93 (0.83-0.97) for learning effect and 0.99 (0.97-1.00) for reliability. Standardised response means (95% CI) were 0.87 (0.58-1.16) and 0.91 (0.78-1.07). The estimated minimal important difference was three repetitions. End-exercise oxygen consumption, carbon dioxide output, ventilation, breathing frequency and heart rate were similar in the 1-min STS test and 6MWT.The 1-min STS test is a reliable, valid and responsive test for measuring functional exercise capacity in COPD patients and elicited a physiological response comparable to that of the 6MWT.

Validity and reliability of strain gauge measurement of volitional quadriceps force in patients with COPD

This study investigated the validity and reliability of fixed strain gauge measurements of isometric quadriceps force in patients with chronic obstructive pulmonary disease (COPD). A total cohort of 138 patients with COPD were assessed. To determine validity, maximal volitional quadriceps force was evaluated during isometric maximal voluntary contraction (MVC) manoeuvre via a fixed strain gauge dynamometer and compared to (a) potentiated non-volitional quadriceps force obtained via magnetic stimulation of the femoral nerve (twitch (Tw); n = 92) and (b) volitional computerized dynamometry (Biodex; n = 46) and analysed via correlation coefficients. Test-retest and absolute reliability were determined via calculations of intra-class correlation coefficients (ICCs), smallest real differences (SRDs) and standard errors of measurement (SEMs). For this, MVC recordings in each device were performed across two test sessions separated by a period of 7 days ( n = 46). Strain gauge measures of MVC demonstrated very large correlation with Tw and Biodex results ( r = 0.86 and 0.88, respectively, both p < 0.0001). ICC, SEM and SRD were numerically comparable between strain gauge and Biodex devices (ICC = 0.96 vs. 0.93; SEM = 8.50 vs. 10.54 N·m and SRD = 23.59 vs. 29.22 N·m, respectively). The results support that strain gauge measures of quadriceps force are valid and reliable in patients with COPD.

Sonographic Measurement of the Quadriceps Muscle in Patients With Chronic Obstructive Pulmonary Disease: Functional and Clinical Implications

OBJECTIVES

The purpose of this study was to determine the association between functionality as assessed by the 6-minute walking test (6MWT), maximal voluntary contraction of the quadriceps (MVCQ), and quadriceps thickness and echo intensity as measured by sonography, in patients with chronic obstructive pulmonary disease (COPD).

METHODS

Maximal voluntary contraction of the quadriceps and the thickness and echo intensity of the rectus femoris and vastus intermedius were evaluated in 20 patients with COPD. Functionality was assessed by the 6MWT. Differences between the evaluated muscles were determined by the Student t test. Pearson and Spearman rank correlation coefficients were used to analyze relationships between variables of interest, according to data characteristics. Finally, multivariate regression models were applied.

RESULTS

There was a positive correlation between MVCQ and rectus femoris and vastus intermedius thickness (r = 0.427; P = .030; r = 0.469; P= .018, respectively) and a negative correlation between MVCQ and rectus femoris and vastus intermedius echo intensity (r= -0.500; P= .012; r= -0.482; P= .016). No correlation was found between MVCQ and the 6MWT (r = 0.319; P = .085). Multivariate regression analysis showed that the rectus femoris echo intensity, vastus intermedius echo intensity, and vastus intermedius thickness explained 70% of the variance in the distance walked during the 6MWT.

CONCLUSIONS

These results indicate that, in patients with COPD, both quadriceps force and exercise capacity are associated with quantitative (thickness) and qualitative (echo intensity) characteristics of the quadriceps. Consequently, comprehensive assessments of peripheral muscles should simultaneously include both measurements.

Is the 1-minute sit-to-stand test a good tool for the evaluation of the impact of pulmonary rehabilitation? Determination of the minimal important difference in COPD

Background

The 1-minute sit-to-stand (STS) test could be valuable to assess the level of exercise tolerance in chronic obstructive pulmonary disease (COPD). There is a need to provide the minimal important difference (MID) of this test in pulmonary rehabilitation (PR).

Methods

COPD patients undergoing the 1-minute STS test before PR were included. The test was performed at baseline and the end of PR, as well as the 6-minute walk test, and the quadriceps maximum voluntary contraction (QMVC). Home and community-based programs were conducted as recommended. Responsiveness to PR was determined by the difference in the 1-minute STS test between baseline and the end of PR. The MID was evaluated using distribution and anchor-based methods.

Results

Forty-eight COPD patients were included. At baseline, the significant predictors of the number of 1-minute STS repetitions were the 6-minute walk distance (6MWD) (r=0.574; P<10⁻³), age (r=−0.453; P=0.001), being on long-term oxygen treatment (r=−0.454; P=0.017), and the QMVC (r=0.424; P=0.031). The multivariate analysis explained 75.8% of the variance of 1-minute STS repetitions. The improvement of the 1-minute STS repetitions at the end of PR was 3.8±4.2 (P<10⁻³). It was mainly correlated with the change in QMVC (r=0.572; P=0.004) and 6MWD (r=0.428; P=0.006). Using the distribution-based analysis, an MID of 1.9 (standard error of measurement method) or 3.1 (standard deviation method) was found. With the 6MWD as anchor, the receiver operating characteristic curve identified the MID for the change in 1-minute STS repetitions at 2.5 (sensibility: 80%, specificity: 60%) with area under curve of 0.716.

Conclusion

The 1-minute STS test is simple and sensitive to measure the efficiency of PR. An improvement of at least three repetitions is consistent with physical benefits after PR.

Why and How Limb Muscle Mass and Function Should Be Measured in Patients with Chronic Obstructive Pulmonary Disease

Impaired limb muscle function is a common occurrence in patients with chronic obstructive pulmonary disease (COPD), and it negatively influences exercise tolerance, quality of life, and even survival. Assessment of limb muscle mass and function in COPD is highly encouraged; it should include the quadriceps muscle, but other lower and upper limb muscles may also be evaluated to provide valuable information. Quantification of muscle mass as well as assessment of muscle strength and endurance are suggested. Bioelectrical impedance and dual-energy X-ray absorption can be realistically used in the clinical environment to monitor body composition. Although sophisticated computerized dynamometers provide the most accurate assessment, simple exercise and testing equipment are valid alternatives and they should help in implementing limb muscle function assessment in clinical settings. Isometric measurements, using strain-gauges or hand-held dynamometers, should be favored for their simplicity, availability, and quality of information provided. This perspective provides a rationale for the evaluation of limb muscle mass and function in COPD in routine clinical practice. In addition, measurement techniques used to assess limb muscle mass, strength, endurance, and fatigue in various clinical settings are discussed.

Sit-to-stand test and 6-min walking test correlation in patients with chronic obstructive pulmonary disease

BACKGROUND:

The 6-min walking test (6MWT) is one of the most commonly used tests to assess exercise capacity during chronic obstructive pulmonary disease (COPD). However, it is a relatively time-consuming test. Many authors assessed the usefulness of simpler methods, as the sit-to-stand test (STST), to estimate exercise capacity.

PURPOSE:

To demonstrate the feasibility of STST, in comparison to 6MWT, for the evaluation of functional status in Tunisian COPD patients and evaluate its correlation to the severity of the disease.

METHODS:

We studied patients with COPD (Global Initiative for Chronic Obstructive Lung Disease A-D). All patients had plethysmography and manual quadriceps femoris muscle strength evaluation. Each patient completed a 6MWT and a STST. During the tests, dyspnea severity (Borg scale), heart rate, pulsed oxygen saturation, and blood pressure were measured.

RESULTS:

In 49 patients with stable COPD (mean age 67.06 ± 8.4 years, mean forced expiratory volume in the first second 46.25% ± 19.64%), 6MWT and STST were correlated with each other (r = 0.47, P = 0.001). During 6MWT and STST, the rise in heart rate, systolic blood pressure, and severity of dyspnea were statistically significant compared to baseline (P < 0.05). However, cardiorespiratory stress was lower after STST than after 6MWT (P < 0.05). A statistically significant positive correlation was noted between the 6MWT distance and forced vital capacity (r = 0.357, P < 0.05). The 6MWT was negatively correlated with dyspnea severity at baseline (r = −0.289, P < 0.05) and with BODE index (r = −0.672, P < 0.01). STST was correlated only with age (r = 0.377, P < 0.01). No correlation was found between both tests and quadriceps femoris strength.

CONCLUSION:

As like as 6MWT, STST can determine functional status during COPD. In addition, it is less time consuming and produces less hemodynamical stress compared to 6MWT. STST can be used as an alternative for 6MWT in patients with COPD.

Impact of sleep quality on functional capacity, peripheral muscle strength and quality of life in patients with chronic obstructive pulmonary disease

PURPOSE

The purpose of this study was to assess the impact of quality of sleep on functional capacity, peripheral muscle strength and quality of life in patients with chronic obstructive pulmonary disease (COPD).

MATERIALS AND METHODS

Forty patients with COPD (61.6 ± 8.28 years) were included in this study. Subjective sleep quality (Pittsburgh sleep quality index), quality of life (Nottingham health profile), quadriceps muscle strength (QMS) and functional capacity (6-min walk test) were assessed.

RESULTS

Poor sleep quality (Pittsburgh sleep quality index total >5) was present in 57% of the patients. Patients with a poor sleep quality had significantly lower QMS and higher exercise heart rate (p < 0.05). The Pittsburgh sleep quality index total score was associated with QMS, Nottingham health profile physical mobility and sleep scores, exercise fatigue and dyspnea (p < 0.05).

CONCLUSION

Sleep quality is affected in a majority of patients with COPD. It is related with symptoms, functional capacity, peripheral muscle strength and general quality of life.

Early telemedicine training and counselling after hospitalization in patients with severe chronic obstructive pulmonary disease: a feasibility study

Background

An essential element in the treatment of patients with chronic obstructive pulmonary disease (COPD) is rehabilitation, of which supervised training is an important part. However, not all individuals with severe COPD can participate in the rehabilitation provided by hospitals and municipal training centres due to distance to the training venues and transportation difficulties. The aim of the study was to assess the feasibility of an individualized home-based training and counselling programme via video conference to patients with severe COPD after hospitalization including assessment of safety, clinical outcomes, patients’ perceptions, organisational aspects and economic aspects.

Methods

The design was a pre- and post-test intervention study. Fifty patients with severe COPD were included. The telemedicine training and counselling included three weekly supervised exercise sessions by a physiotherapist and up to two supervised counselling and training sessions in energy conservation techniques by an occupational therapist. The telemedicine videoconferencing equipment was a computer containing a screen, a microphone, an on/off switch and a volume control.

Results

Thirty seven (74%) participants completed the programme, with improvements in health status assessed by the Clinical COPD Questionnaire and physical performance assessed by a sit-to-stand test and a timed-up-and-go test. There were no cases of patient fall or emergency contact with a general practitioner during the telemedicine training sessions. The study participants believed the telemedicine training and counselling was essential for getting started with being physically active in a secure manner. The business case showed that under the current financing system, the reimbursement to the hospital was slightly higher than the hospital expenditures. Thus, the business case for the hospital was positive. The organizational analysis indicated that the perceptions of the staff were that the telemedicine service had improved the continuity of the rehabilitation programme for the patients and enabled the patients’ everyday lives to be included in the treatment.

Conclusions

This study showed that home-based supervised training and counselling via video conference is safe and feasible and that telemedicine can help to ensure more equitable access to supervised training in patients with severe COPD.

Trial registration

Clinical Trials NCT02085187 (Date of registration 10.03.2014).