Use of exercise testing in the evaluation of interventional efficacy: an official ERS statement

Cardiopulmonary exercise testing in patients with asthma: What is its clinical value?

Asthma is one of the most common respiratory disorders, characterized by fully or largely reversible airflow limitation. Asthma symptoms can be triggered or magnified during exertion, while physical activity limitation is often present among asthmatic patients. Cardiopulmonary exercise testing (CPET) is a dynamic, non-invasive technique which provides a thorough assessment of exercise physiology, involving the integrative assessment of cardiopulmonary, neuromuscular and metabolic responses during exercise. This review summarizes current evidence regarding the utility of CPET in the diagnostic work-up, functional evaluation and therapeutic intervention among patients with asthma, highlighting its potential role for thorough patient assessment and physician clinical desicion-making.

Cardiopulmonary exercise testing in chronic obstructive pulmonary disease: An update on its clinical value and applications

Chronic obstructive pulmonary disease is a debilitating disorder, characterized by airflow limitation, exercise impairment, reduced functional capacity and significant systemic comorbidity, which complicates the course of the disease. The critical inspiratory constraint to tidal volume expansion during exercise (that may be further complicated by the presence of dynamic hyperinflation), abnormalities in oxygen transportation and gas exchange abnormalities are the major pathophysiological mechanisms of exercise intolerance in COPD patients, and thus, exercise testing has been traditionally used for the functional evaluation of these patients. Compared to various laboratory and field exercise tests, cardiopulmonary exercise testing (CPET) provides a thorough assessment of exercise physiology, involving the integrative respiratory, cardiovascular, muscle and metabolic responses to exercise. This review highlights the clinical utility of CPET in COPD patients, as it provides important information for the determination of the major factors that limit exercise among patients with several comorbidities, allows the assessment of the severity of dynamic hyperinflation, provides valuable prognostic information and can be used to evaluate the response to several therapeutic interventions.

The impact of high-flow nasal cannula oxygen therapy on exercise capacity in fibrotic interstitial lung disease: a proof-of-concept randomized controlled crossover trial

Background

Patients with fibrotic interstitial lung disease (FILD) often experience gas exchange abnormalities and ventilatory limitations, resulting in reduced exercise capacity. High-flow nasal cannula (HFNC) oxygen therapy is a novel treatment, whose physiological beneficial effects have been demonstrated in various clinical settings. We hypothesized that HFNC oxygen therapy might be superior to conventional oxygen therapy for improving exercise capacity in FILD patients.

Methods

We performed a prospective randomized controlled crossover trial with a high-intensity constant work-rate endurance test (CWRET) using HFNC (50 L/min, FiO₂ 0.5) and a venturi mask (VM) (15 L/min, FiO₂ 0.5) for oxygen delivery in FILD patients. The primary outcome variable was endurance time. The secondary outcome variables were SpO₂, heart rate, Borg scale (dyspnea and leg fatigue), and patient’s comfort.

Results

Seven hundred and eleven patients were screened and 20 eligible patients were randomized. All patients completed the trial. The majority of patients were good responders to VM and HFNC compared with the baseline test (VM 75%; HFNC 65%). There was no significant difference in endurance time between HFNC and VM (HFNC 6.8 [95% CI 4.3–9.3] min vs VM 7.6 [95% CI 5.0–10.1] min, p = 0.669). No significant differences were found in other secondary endpoints. Subgroup analysis with HFNC good responders revealed that HFNC significantly extended the endurance time compared with VM (VM 6.4 [95%CI 4.5–8.3] min vs HFNC 7.8 [95%CI 5.8–9.7] min, p = 0.046), while no similar effect was observed in the VM good responders.

Conclusions

HFNC did not exceed the efficacy of VM on exercise capacity in FILD, but it may be beneficial if the settings match. Further large studies are needed to confirm these findings.

Trial registration

UMIN-CTR: UMIN000021901.

Effect of Breathing Oxygen-Enriched Air on Exercise Performance in Patients with Chronic Obstructive Pulmonary Disease: Randomized, Placebo-Controlled, Cross-Over Trial

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) experience dyspnea and hypoxemia during exercise.

OBJECTIVE

The aim of this study was to evaluate the effects of breathing oxygen-enriched air on exercise performance and associated physiological changes in patients with COPD.

METHODS

In a randomized, placebo-controlled, single-blind, cross-over trial, 20 patients with COPD (11 women, age 65 ± 6 years, FEV1 64 ± 19% pred., resting SpO2 ≥90%) performed 4 cycle ergospirometries to exhaustion using an incremental exercise test (IET) and a constant work rate (at 75% maximal workload with air) exercise test (CWRET), each with ambient (FiO2 0.21) and oxygen-enriched (FiO2 0.5) air. The main outcomes were the change in maximal workload in the IET and the change in exercise duration in the CWRET with oxygen versus air. Electrocardiogram, pulmonary gas exchange, thoracic volumes by inductance plethysmography, arterial blood gases, and cerebral and quadriceps muscle tissue oxygenation (CTO and MTO) were additionally measured.

RESULTS

In the IET, maximal workload increased from 96 ± 21 to 104 ± 28 W with oxygen. In the CWRET, exercise duration increased from 605 ± 274 to 963 ± 444 s with oxygen. At end-exercise with oxygen, CTO, MTO, PaO2, and PaCO2 were increased, while V'E/V'CO2 was reduced and thoracic volumes were similar. At the corresponding time to end of exercise with ambient air, oxygen decreased heart rate, respiratory rate, minute ventilation, and V'E/V'CO2, while oxygenation was increased.

CONCLUSION

In COPD patients without resting hypoxemia, breathing oxygen-enriched air improves exercise performance. This relates to a higher arterial oxygen saturation promoting oxygen availability to muscle and cerebral tissue and an enhanced ventilatory efficiency. COPD patients may benefit from oxygen therapy during exercise training.

Cardiopulmonary Exercise Testing for Preoperative Evaluation: What Does the Future Hold?

Purpose of Review

Cardiopulmonary exercise testing (CPET) informs the preoperative evaluation process by providing individualised risk profiles; guiding shared decision-making, comorbidity optimisation and preoperative exercise training; and informing perioperative patient management. This review summarises evidence on the role of CPET in preoperative evaluation and explores the role of novel and emerging CPET variables and alternative testing protocols that may improve the precision of preoperative evaluation in the future.

Recent Findings

CPET provides a wealth of physiological data, and to date, much of this is underutilised clinically. For example, impaired chronotropic responses during and after CPET are simple to measure and in recent studies are predictive of both cardiac and noncardiac morbidity following surgery but are rarely reported. Exercise interventions are increasingly being used preoperatively, and endurance time derived from a high intensity constant work rate test should be considered as the most sensitive method of evaluating the response to training. Further research is required to identify the clinically meaningful difference in endurance time. Measuring efficiency may have utility, but this requires exploration in prospective studies.

Summary

Further work is needed to define contemporaneous risk thresholds, to explore the role of other CPET variables in risk prediction, to better characterise CPET’s role in combination with other tools in multifactorial risk stratification and increasingly to evaluate CPET’s utility for preoperative exercise prescription in prehabilitation.

The role of phenotype on ventilation and exercise capacity in patients affected by COPD: a retrospective study

Background

The idea of phenotype in chronic obstructive pulmonary disease (COPD) has evolved in the last decades, and the importance of peculiar treatment strategies has now been acknowledged. Although dyspnea and exercise limitation are hallmarks of COPD, this aspect has never been fully explored in literature in terms of disease phenotype. The aim of the present study was to explore the relevance of clinical COPD phenotypes on exercise ventilation and maximal capacity.

Methods

In this observational cohort retrospective study we analyzed the data of 50 COPD patients who underwent cardiopulmonary exercise test, categorized as emphysematous (n=29), and non-emphysematous (n=21) according to a previously validated model.

Results

We found a significant difference in terms of VE/VCO₂ slope (median values 32.4 vs 28.0, p=0.015) and VE/VCO₂ ratio at nadir (median values 37 vs. 33, p=0.004), which resulted higher in emphysematous patients, who also presented lower P_ETCO₂ values (median values 32.6 vs 35.6, p=0.008). In a subgroup of 31 tests which met the maximality criteria, emphysematous patients presented a significantly lower work rate at peak (median value 51 vs 72% predicted, p=0.016), and showed a lower peak oxygen consumption, although at the limit of significance (median values of 63 vs 85 % predicted, p=0.051).

Conclusions

This study extends our knowledge about the characterization of the COPD phenotypical expression of disease, showing that patients affected by emphysema are more prone to ventilatory inefficiency during exercise, and that this is likely to be an important cause of their overall reduced exercise capacity.

Exercise capacity and ventilation inhomogeneity in cystic fibrosis: A cross-sectional study

BACKGROUND

Lung clearance index (LCI_2.5 ) is a marker of overall lung ventilation inhomogeneity and has proven to be able to detect early peripheral damage in subjects with cystic fibrosis (CF), with greater sensitivity than conventional spirometry. Combining its sensitivity with the output of an incremental exercise testing, we hypothesized that any sign of ventilation inhomogeneity in subjects without severe airflow obstruction and with a normal exercise tolerance could be relevant for the CF team, tracking early lung disease and potential exercise limiting factors.

METHODS

Patients with CF in clinical stable conditions were recruited between 2015 and 2017. Available spirometry, nitrogen multiple-breath washout test and symptoms-limited exercise testing performed as parts of patients' annual routine evaluation were considered for this cross-sectional study. To describe the relationship between exercise intensity and ventilation inhomogeneity, a linear regression analysis was performed using backward elimination based on Akaike information criteria.

RESULTS

Seventy-seven patients (38 females) were included. S_acin and LCI_2.5 were significantly higher in patients with an overall reduced exercise tolerance. Peak work developed during exercise was associated with body mass index (b = 5.25; 95% confidence interval [CI] = 1.53-8.98), forced expiratory volume in 1 second (FEV₁ ; b = 3.71; 95% CI = 1.96-5.46), Pseudomonas aeruginosa chronic infection (b = -8.84; 95% CI = -15.84 to -1.84) but not with LCI_2.5 .

CONCLUSION

Exercise capacity and airflow obstruction are associated in this Italian CF cohort. Considering the greater discriminatory power of LCI_2.5 over FEV₁ and peak work, the Godfrey protocol without gas analysis cannot provide detailed information about lung function or efficiency. However, this incremental protocol without gas exchange measures can still provide the CF team with information about exercise tolerance and disability.

Dyspnea in COPD: New Mechanistic Insights and Management Implications

Dyspnea is the most common symptom experienced by patients with chronic obstructive pulmonary disease (COPD). To avoid exertional dyspnea, many patients adopt a sedentary lifestyle which predictably leads to extensive skeletal muscle deconditioning, social isolation, and its negative psychological sequalae. This "dyspnea spiral" is well documented and it is no surprise that alleviation of this distressing symptom has become a key objective highlighted across COPD guidelines. In reality, this important goal is often difficult to achieve, and successful symptom management awaits a clearer understanding of the underlying mechanisms of dyspnea and how these can be therapeutically manipulated for the patients' benefit. Current theoretical constructs of the origins of activity-related dyspnea generally endorse the classical demand-capacity imbalance theory. Thus, it is believed that disruption of the normally harmonious relationship between inspiratory neural drive (IND) to breathe and the simultaneous dynamic response of the respiratory system fundamentally shapes the expression of respiratory discomfort in COPD. Sadly, the symptom of dyspnea cannot be eliminated in patients with advanced COPD with relatively fixed pathophysiological impairment. However, there is evidence that effective symptom palliation is possible for many. Interventions that reduce IND, without compromising alveolar ventilation (VA), or that improve respiratory mechanics and muscle function, or that address the affective dimension, achieve measurable benefits. A common final pathway of dyspnea relief and improved exercise tolerance across the range of therapeutic interventions (bronchodilators, exercise training, ambulatory oxygen, inspiratory muscle training, and opiate medications) is reduced neuromechanical dissociation of the respiratory system. These interventions, singly and in combination, partially restore more harmonious matching of excessive IND to ventilatory output achieved. In this review we propose, on the basis of a thorough review of the recent literature, that effective dyspnea amelioration requires combined interventions and a structured multidisciplinary approach, carefully tailored to meet the specific needs of the individual.

The therapeutic effects of bronchial thermoplasty evaluated by cardiopulmonary exercise testing : a case series

Bronchial thermoplasty (BT) had been reported to improve the symptoms of severe asthma. However, the exertional responses of BT based on the mechanisms have not been elucidated. A 57-year-old man and a 60-year-old woman underwent BT due to intractable severe asthma. We evaluated the therapeutic effects of BT using cardiopulmonary exercise testing (CPET). After BT, the exercise time during CPET substantially prolonged reducing exertional dyspnea in the former (good), but not in the latter (poor). In the good responder, the high air remaining in the lung after expiration (i.e., inspiratory tidal volume minus expiratory tidal volume) during CPET decreased after BT. In contrast, in the poor responder, the high air remaining after expiration during exercise was not obtained before BT. Further investigations are necessary to confirm that the presence or absence of the exertional wasted ventilation on CPET may be informative to evaluate the therapeutic effects of BT. J. Med. Invest. 67 : 386-390, August, 2020.

Comparative measurement properties of constant work rate cycling and the endurance shuttle walking test in COPD: the TORRACTO® clinical trial

BACKGROUND

Exercise tolerance is an important endpoint in chronic obstructive pulmonary disease (COPD) clinical trials. Little is known about the comparative measurement properties of constant work rate cycle ergometry (CWRCE) and the endurance shuttle walking test (ESWT). The objective of this sub-analysis of the TORRACTO® study was to directly compare the endurance measurement properties of CWRCE and ESWT in patients with COPD in a multicentre, multinational setting. We predicted that both tests would be similarly reliable, but that the ESWT would be more responsive to bronchodilation than CWRCE.

METHODS

This analysis included 151 patients who performed CWRCE and ESWT at baseline and week 6 after receiving once-daily placebo, tiotropium/olodaterol (T/O) 2.5/5 μg or T/O 5/5 μg. Reproducibility was assessed by comparing their respective performance at baseline and week 6 in the placebo group. Responsiveness to bronchodilation was assessed by comparing endurance time at week 6 with T/O with baseline values and placebo. The locus of symptom limitation and end-exercise Borg scales for breathing and leg discomfort for both tests were also analysed.

RESULTS

The intraclass correlation coefficients for CWRCE and ESWT were 0.56 [95% confidence interval (CI) 0.37-0.71] and 0.75 (95% CI 0.63-0.84). More patients were limited by breathing discomfort during the ESWT than during CWRCE, whereas more patients were limited by leg discomfort or breathing/leg discomfort during CWRCE than the ESWT (p <0.0001). Both tests were responsive to bronchodilator treatment: there was a 19% increase in endurance time from baseline at week 6 (p = 0.0006) assessed with CWRCE, and a 20% increase in endurance time assessed with ESWT (p = 0.0013).

CONCLUSIONS

Both exercise tests performed well in a multicentre clinical trial. Although the locus of symptom limitation differed between the two tests, both were reliable and responsive to bronchodilation. For future clinical trials, the choice of test should depend on the study requirements.

CLINICALTRIALS.GOV IDENTIFIER

NCT01525615. The reviews of this paper are available via the supplemental material section.

ERS statement on standardisation of cardiopulmonary exercise testing in chronic lung diseases

The objective of this document was to standardise published cardiopulmonary exercise testing (CPET) protocols for improved interpretation in clinical settings and multicentre research projects. This document: 1) summarises the protocols and procedures used in published studies focusing on incremental CPET in chronic lung conditions; 2) presents standard incremental protocols for CPET on a stationary cycle ergometer and a treadmill; and 3) provides patients' perspectives on CPET obtained through an online survey supported by the European Lung Foundation. We systematically reviewed published studies obtained from EMBASE, Medline, Scopus, Web of Science and the Cochrane Library from inception to January 2017. Of 7914 identified studies, 595 studies with 26 523 subjects were included. The literature supports a test protocol with a resting phase lasting at least 3 min, a 3-min unloaded phase, and an 8- to 12-min incremental phase with work rate increased linearly at least every minute, followed by a recovery phase of at least 2–3 min. Patients responding to the survey (n=295) perceived CPET as highly beneficial for their diagnostic assessment and informed the Task Force consensus. Future research should focus on the individualised estimation of optimal work rate increments across different lung diseases, and the collection of robust normative data.

The document facilitates standardisation of conducting, reporting and interpreting cardiopulmonary exercise tests in chronic lung diseases for comparison of reference data, multi-centre studies and assessment of interventional efficacy.http://bit.ly/31SXeB5

A new maximal bicycle test using a prediction algorithm developed from four large COPD studies

Background: Maximum exercise workload (W_MAX) is today assessed as the first part of Cardiopulmonary Exercise testing. The W_MAX test exposes patients with COPD, often having cardiovascular comorbidity, to risks. Our research project was initiated with the final aim to eliminate the W_MAX test and replace this test with a predicted value of W_MAX, based on a prediction algorithm of W_MAX derived from multicentre studies.

Methods: Baseline data (W_MAX, demography, lung function parameters) from 850 COPD patients from four multicentre studies were collected and standardized. A prediction algorithm was prepared using Random Forest modelling. Predicted values of W_MAX were used in a new W_MAX test, which used a linear increase in order to reach the predicted W_MAX within 8 min. The new W_MAX test was compared with the standard stepwise W_MAX test in a pilot study including 15 patients with mild/moderate COPD.

Results: The best prediction algorithm of W_MAX included age, sex, height, weight, and six lung function parameters. FEV₁ and DLCO were the most important predictors. The new W_MAX test had a better correlation (R² = 0.84) between predicted and measured W_MAX than the standard W_MAX test (R² = 0.66), with slopes of 0.50 and 0.46, respectively. The results from the new W_MAX test and the standard W_MAX test correlated well.

Conclusion: A prediction algorithm based on data from four large multicentre studies was used in a new W_MAX test. The prediction algorithm provided reliable values of predicted W_MAX. In comparison with the standard W_MAX test, the new W_MAX test provided similar overall results.

Clinical Effects Of Acupuncture On The Pathophysiological Mechanism Of Chronic Obstructive Pulmonary Disease During Exercise

Purpose

Pharmacological therapy and pulmonary rehabilitation are useful for exertional dyspnoea in patients with chronic obstructive pulmonary disease (COPD); however, several patients have no meaningful improvements. Although acupuncture significantly improves exercise intolerance and dyspnoea, the pathophysiological mechanism of these effects is unknown; therefore, we evaluated this mechanism using cardiopulmonary exercise testing in a single-arm, open experimental study.

Patients and methods

Sixteen patients with COPD underwent acupuncture once a week for 12 weeks. Primary outcomes were exercise performance parameters, including peak oxygen uptake in the incremental exercise tests (IETs) and the time to the limit of tolerance measured in constant work rate exercise tests (CWRETs) at 70% peak work-rate of the IET. IETs and CWRETs were performed at baseline and at weeks 12, 16, and 24.

Results

During the time course, there were significant increases in peak oxygen uptake (p = 0.018) and minute ventilation (V̇_E, p = 0.04) in the IETs. At 12 weeks, the endurance time significantly increased (810 ± 470 vs 1125 ± 657 s, p < 0.001) and oxygen uptakes at terminated exercise were significantly lower (771 ± 149 mL/min, p < 0.05) than those at baseline (822 ± 176 mL/min) in CWRETs. The significant decreases in oxygen uptake and minute ventilation and improvements in Borg scale scores were also observed during CWRETs after acupuncture. The decreases at isotime in the Borg scale (r = −0.789, p = 0.0007) and V̇_E (r = −0.6736, p = 0.0042) were significantly correlated with the improvement of endurance time.

Conclusion

The positive effects of acupuncture on exertional dyspnoea were associated with increased endurance time influenced by improved oxygen utilisation and reduced ventilation during exercise. Acupuncture may be a new intervention for COPD in addition to conventional maintenance therapies.

Intensity and quality of exertional dyspnoea in patients with stable pulmonary hypertension

Dynamic hyperinflation is observed during exercise in 60% of patients with clinically stable pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), intensifying exertional dyspnoea. The impact of dynamic changes in respiratory mechanics during exercise on qualitative dimensions of dyspnoea in these patients has not been evaluated.

26 patients (PAH n=17; CTEPH n=9) performed an incremental symptom-limited cycle exercise test. Minute ventilation (V′E), breathing pattern, operating lung volumes and dyspnoea intensity were assessed throughout exercise. Dyspnoea quality was serially assessed during exercise using a three-item questionnaire (dyspnoea descriptors). The inflection point of tidal volume (VT) relative to V′E was determined for each incremental test. Changes in inspiratory capacity during exercise defined two groups of patients: hyperinflators (65%) and non-hyperinflators (35%). Multidimensional characterisation of dyspnoea was performed after exercise using the Multidimensional Dyspnea Profile.

In hyperinflators, inspiratory capacity decreased progressively throughout exercise by 0.36 L, while remaining stable in non-hyperinflators. The “work/effort” descriptor was most frequently selected throughout exercise in both types of patients (65% of all responses). At the VT/V′E inflection, work/effort plateaued while “unsatisfied inspiration” descriptors became selected predominantly only in hyperinflators (77% of all responses). In the affective domain, the emotion most frequently associated with dyspnoea was anxiety.

In pulmonary hypertension patients who develop hyperinflation during exercise, dyspnoea descriptors referring to unsatisfied inspiration become predominant following the VT/V′E inflection. As these descriptors are generally associated with more negative emotional experiences, delaying or preventing the VT/V′E inflection may have important implications for symptom management in patients with pulmonary hypertension.

Effect of Vaporized Cannabis on Exertional Breathlessness and Exercise Endurance in Advanced Chronic Obstructive Pulmonary Disease. A Randomized Controlled Trial

RATIONALE

A series of studies conducted approximately 40 years ago demonstrated an acute bronchodilator effect of smoked cannabis in healthy adults and adults with asthma. However, the acute effects of vaporized cannabis on airway function in adults with advanced chronic obstructive pulmonary disease (COPD) remain unknown.

OBJECTIVES

To test the hypothesis that inhaled vaporized cannabis would alleviate exertional breathlessness and improve exercise endurance by enhancing static and dynamic airway function in COPD.

METHODS

In a randomized controlled trial of 16 adults with advanced COPD (forced expiratory volume in 1 second [FEV₁], mean ± SD: 36 ± 11% predicted), we compared the acute effect of 35 mg of inhaled vaporized cannabis (18.2% Δ⁹-tetrahydrocannabinol, <0.1% cannabidiol) versus 35 mg of a placebo control cannabis (CTRL; 0.33% Δ⁹-tetrahydrocannabinol, <0.99% cannabidiol) on physiological and perceptual responses during cardiopulmonary cycle endurance exercise testing; spirometry and impulse oscillometry at rest; and cognitive function, psychoactivity, and mood.

RESULTS

Compared with CTRL, cannabis had no effect on breathlessness intensity ratings during exercise at isotime (cannabis, 2.7 ± 1.2 Borg units vs. CTRL, 2.6 ± 1.3 Borg units); exercise endurance time (cannabis, 3.8 ± 1.9 min vs. CTRL, 4.2 ± 1.9 min); cardiac, metabolic, gas exchange, ventilatory, breathing pattern, and/or operating lung volume parameters at rest and during exercise; spirometry and impulse oscillometry-derived pulmonary function test parameters at rest; and cognitive function, psychoactivity, and mood.

CONCLUSIONS

Single-dose inhalation of vaporized cannabis had no clinically meaningful positive or negative effect on airway function, exertional breathlessness, and exercise endurance in adults with advanced COPD. Clinical trial registered with www.clinicaltrials.gov (NCT03060993).

Effects of lung deflation induced by tiotropium/olodaterol on the cardiocirculatory responses to exertion in COPD

BACKGROUND

Hyperinflation has been associated with negative cardiocirculatory consequences in patients with chronic obstructive pulmonary disease (COPD). These abnormalities are likely to worsen when the demands for O₂ increase, e.g., under the stress of exercise. Thus, pharmacologically-induced lung deflation may improve cardiopulmonary interactions and exertional cardiac output leading to higher limb muscle blood flow and oxygenation in hyperinflated patients with COPD.

METHODS

20 patients (residual volume = 201.6 ± 63.6% predicted) performed endurance cardiopulmonary exercise tests (75% peak) 1 h after placebo or tiotropium/olodaterol 5/5 μg via the Respimat® inhaler (Boehringer Ingelheim, Ingelheim am Rhein, Germany). Cardiac output was assessed by signal-morphology impedance cardiography. Near-infrared spectroscopy determined quadriceps blood flow (indocyanine green dye) and intra-muscular oxygenation.

RESULTS

Tiotropium/olodaterol was associated with marked lung deflation (p < 0.01): residual volume decreased by at least 0.4 L in 14/20 patients (70%). The downward shift in the resting static lung volumes was associated with less exertional inspiratory constraints and dyspnoea thereby increasing exercise endurance by ~50%. Contrary to our premises, however, neither central and peripheral hemodynamics nor muscle oxygenation improved after active intervention compared to placebo. These results were consistent with those found in a subgroup of patients showing the largest decrements in residual volume (p < 0.05).

CONCLUSIONS

The beneficial effects of tiotropium/olodaterol on resting and operating lung volumes are not translated into enhanced cardiocirculatory responses to exertion in hyperinflated patients with COPD. Improvement in exercise tolerance after dual bronchodilation is unlikely to be mechanistically linked to higher muscle blood flow and/or O₂ delivery.

The minimal important difference for the endurance shuttle walk test in individuals with chronic obstructive pulmonary disease following a course of pulmonary rehabilitation

The endurance shuttle walk test (ESWT) is frequently used as an outcome measure for pulmonary rehabilitation (PR). The minimal important difference (MID) for the ESWT after a course of rehabilitation has not been conclusively confirmed in the literature. The aim was to establish the MID for the ESWT following the 6-week PR programme in patients with chronic obstructive pulmonary disease (COPD). Following the completion of the 6-week PR programme, data from 531 participants were included in the analysis to estimate the MID for the ESWT using both anchor-based and distribution-based methods. Mean age (standard deviation (SD)) was 69.4 (9.1) years, 303 male, FEV₁/FVC 0.51 (0.16). The baseline incremental shuttle walk test (ISWT) was 217.7 (SD 139.8) metres and ESWT 195.8 (SD 118.8) seconds, which increased to 279.6 (SD 149.5) metres and 537.4 (SD 378.3) seconds, respectively, following PR. The mean change was 61.8 (95% confidence interval (CI) 56.0–67.5) metres for the ISWT and 342.0 (95% CI 312.4–371.6) seconds for the ESWT. The distribution method (0.5 × SD) yielded an MID of 173.7 seconds, the global rating of change scale method yielded a value of 279.2 (95% CI 244.9–313.5) seconds for those rating themselves as ‘slightly improved’ and the ROC method 207 seconds. There was no agreement between the approaches employed. However, we propose that the MID for the ESWT in COPD following a 6-week PR programme is between 174 and 279 seconds.

Bronchodilators for hyperinflation in COPD associated with biomass smoke: clinical trial

Introduction

The efficacy of long-acting bronchodilators for COPD associated with biomass (BE-COPD) has not been properly evaluated.

Objective

To determine the acute effect of indacaterol (IND) 150 μg q.d and tiotropium (TIO) 18 μg q.d. on lung hyperinflation, walking distance (WD) and dyspnea during the six-minute walking test (6MWT) in moderate BE-COPD at 30, 60 and 240 mins post-drug administration.

Design

Randomized, controlled, open-level, crossover noninferiority clinical trial. Forty-two women with BE-COPD were randomly assigned to a bronchodilator sequence: IND–TIO or vice versa.

Results

There were statistically significant changes over time in inspiratory capacity (IC) (p<0.0001), FEV₁ (p<0.0001) and FVC (p<0.0001) when IND was used. When TIO was administered, an increase over all time periods was observed only for FEV₁ (p<0.0001) and FVC (p<0.0001), whereas for IC an increase was observed only at 30 mins and 24 hrs after TIO administration. We did not find clinically significant increases in WD and dyspnea after the administration of both bronchodilators.

Conclusion

Both IND and TIO showed significant and fast onset improvement in hyperinflation. Therefore, either of them may be recommended as a first line of treatment for COPD associated with BE-COPD.

Is Two Better Than One? The Impact of Doubling Training Volume in Severe COPD: A Randomized Controlled Study

Patients with severe chronic obstructive pulmonary disease (COPD) are unable to exercise at high intensities for sufficiently long periods of time to obtain true physiological training effects. It therefore appears sensible to increase training duration at sub-maximal exercise intensities to optimize the benefit of exercise training. We compared the effects on exercise tolerance of two endurance cycloergometer submaximal exercise protocols with different cumulative training loads (one (G1) versus two (G2) daily 40 min training sessions) both implemented over 20 consecutive days in 149 patients with COPD (forced expiratory volume at first second (FEV₁): 39% predicted) admitted to an inpatient pulmonary rehabilitation program. Patients in G2 exhibited greater improvement (p = 0.011) in submaximal endurance time (from 258 (197) to 741 (662) sec) compared to G1 (from 303 (237) to 530 (555) sec). Clinically meaningful improvements in health-related quality of life, 6MWT, and chronic dyspnea were not different between groups. Doubling the volume of endurance training is feasible and can lead to an additional benefit on exercise tolerance. Future studies may investigate the applicability and benefits of this training strategy in the outpatient or community-based pulmonary rehabilitation settings to amplify the benefits of exercise interventions.

Hemodynamic effects of portable non-invasive ventilation in healthy men

VitaBreath is a portable, non-invasive ventilation device (pNIV) that relieves shortness of breath in COPD by delivering fixed inspiratory and expiratory positive airway pressures (IPAP/EPAP: 18/8 cmH₂O). Fixed pressures may cause circulatory compromise. We investigated the circulatory effects of pNIV during normal breathing (NB) and after Eucapnic Voluntary Hyperpnoea trials (EVH) sustained at 80% MVV. In a balanced order sequence, 10 healthy men performed four trials on one visit: 1-min of pNIV (intervention) or 1-min quiet breathing (QB) during NB; and 1-min pNIV (intervention) or 1-min QB during recovery from 3-min EVH. Compared to QB, pNIV application was associated with greater cardiac output (CO: 1.6 ± 1.9 L.min^-1; P = 0.03). One minute into recovery from EVH, pNIV caused greater CO (2.2 ± 1.6 L.min^-1; P = 0.01) compared to QB. Mean blood pressure was not different with pNIV compared to control. pNIV increased thoracoabdominal volumes and breathing frequency during NB and recovery from EVH. pNIV application does not induce adverse hemodynamic effects in healthy men.

Patient assessment and selection for pulmonary rehabilitation

Pulmonary rehabilitation (PR) is beneficial for people with several forms of chronic respiratory disease. Given the existing limitations on availability of PR services, it is important to identify participants who are most likely to benefit from it. Identification of criteria for patient referral to PR is challenging, as chronic respiratory diseases and their medical and psychosocial co-morbidities place a complex and multifaceted burden on patients. Although research studies have attempted to identify key parameters predictive of 'responsiveness to PR', to date no firm physiological, psychosocial or other criteria exist by which optimal patient candidacy can be determined. Moreover, individual factors do not reliably predict successful multidimensional PR outcomes. In general, individuals who remain symptomatic with dyspnoea, fatigue and exercise intolerance; who have difficulty performing activities of daily living (ADL); and who are having difficulty coping with or managing their disease despite optimized pharmacological therapy are potential candidates for PR. Patient assessment and outcome measurement are core essential features of PR. To be considered as a PR programme, rehabilitation programmes must demonstrate, at a minimum, assessment and outcome measurement in regard to exercise capacity, dyspnoea and health-related quality of life. Additional parameters, including physical activity, nutritional status, tobacco use status, patient knowledge and self-efficacy, performance of ADL, fatigue, disease exacerbations, hospitalizations and other urgent healthcare utilization, and behavioural outcomes, including coping styles, patient satisfaction and programme metrics, are other relevant and important aspects of patient assessment and outcome measurement that should be considered and undertaken in PR, where feasible.

Reduced exercise ventilatory efficiency in adults with cystic fibrosis and normal to moderately impaired lung function

Despite being a hallmark and an independent prognostic factor in several cardiopulmonary diseases, ventilatory efficiency-i.e., minute ventilation/carbon dioxide output relationship (V̇e/V̇co₂)-has never been systematically explored in cystic fibrosis (CF). To provide a comprehensive frame of reference regarding measures of ventilatory efficiency in CF adults with normal to moderately impaired lung function and to confirm the hypothesis that V̇e/V̇co₂ is a sensitive marker of early lung disease. CF patients were divided into three groups, according to their spirometry: normal (G₁), mild impairment (G₂), and moderate impairment (G₃) in lung function. All participants underwent incremental cardiopulmonary exercise testing on a cycle ergometer. Lowest V̇e/V̇co₂ ratio (nadir) and the slope and the intercept of the linear region of the V̇e/V̇co₂ relationship were contrasted in a two-center retrospective analysis, involving 72 CF patients and 36 healthy controls (HC). Compared with HC, CF patients had significantly higher V̇e/V̇co₂ nadir, slope, and intercept (P < 0.001, P < 0.001, and P = 0.049, respectively). Subgroup analysis revealed significant differences in nadir (P = 0.001) and slope (P = 0.012) values even between HC and G₁. Dynamic hyperinflation related negatively with slope (P = 0.045) and positively with intercept (P = 0.001), while no impact on nadir was observed. Ventilatory inefficiency is a clear feature of adults with CF, even among patients with normal spirometry. V̇e/V̇co₂ nadir seems to be the most reliable metric to describe ventilatory efficiency in CF adults. Further prospective studies are needed to clarify whether V̇e/V̇co₂ could represent a useful marker in the evaluation of early lung disease in CF.NEW & NOTEWORTHY This is the first study to investigate ventilatory efficiency in a cohort of adult cystic fibrosis (CF) patients with nonsevere lung disease. The finding of impaired ventilatory efficiency in patients with normal lung function confirms the higher sensitivity of exercise testing in detecting early lung disease compared with spirometry. Dynamic hyperinflation plays a significant role in determining the behavior of V̇e/V̇co₂ slope and intercept values with increasing lung function impairment. Apparently free from interference from mechanical constraints, V̇e/V̇co₂ nadir seems the most reliable parameter to evaluate ventilatory efficiency in CF adults.

Effect of high-flow nasal therapy during exercise training in COPD patients with chronic respiratory failure: study protocol for a randomised controlled trial

Background

The benefit of pulmonary rehabilitation (PR) in symptomatic chronic obstructive pulmonary disease (COPD) is well known. However, advanced patients with chronic respiratory failure (CRF), a category excluded from most studies, are frequently unable to sustain a work-load sufficiently high to obtain the full benefit of PR on exercise tolerance. Recent studies involving heated and humidified high flow oxygen therapy (HFOT) showed positive effects on breathing pattern and ventilatory efficiency during effort. We thus plan to compare, in COPD patients with CRF undergoing a high-intensity exercise programme, the effect of using HFOT versus standard oxygen delivery via Venturi Mask (V-mask), at the same inspiratory oxygen fraction, on improving exercise endurance.

Methods/Design

This is a multicentre randomised controlled trial that will involve 156 COPD inpatients with CRF recruited from seven PR hospitals. Patients will be randomised to one of two groups – V-mask versus HFOT. All patients will undergo the same high-intensity exercise programme using either of the oxygen delivery devices as per their group allocation. Training will consist of 20 sessions, over 1 month (5 sessions per week) within the hospitalisation period. Anthropometric and clinical data, including body mass index, diagnosis, spirometry and comorbidities (Cumulative Rating Scale) will be collected at baseline. At baseline and at the end of the exercise programme (primary assessment time) evaluation will include exercise tolerance (Constant Work Rate Exercise Test) (primary outcome), functional capacity (6-min walk test), maximal inspiratory pressure/maximal expiratory pressure, peripheral muscle strength (biceps and quadriceps) by manual dynamometer, respiratory exchanges (blood gases analysis), disability (Barthel Index and Barthel Dyspnoea Index), impact of disease (COPD Assessment test), and quality of life (Maugeri Respiratory Failure Scale-26). At the end of the training period, patient satisfaction will be evaluated.

Discussion

This study will add knowledge about the exercise response in advanced COPD with CRF and verify if an alternative tool, namely HFOT, can increase the benefit obtained from PR.

Trial registration

ClinicalTrials.gov ID NET03322787

Registered: 6 November 2017

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3440-2) contains supplementary material, which is available to authorized users.

FKBP5 rs4713916: A Potential Genetic Predictor of Interindividual Different Response to Inhaled Corticosteroids in Patients with Chronic Obstructive Pulmonary Disease in a Real-Life Setting

Background: Chronic obstructive pulmonary disease (COPD) is a common, preventable, and manageable lung disease characterized by large heterogeneity in disease presentation and grades impairment. Inhaled corticosteroids (ICS) are commonly used to manage COPD/COPD-exacerbation. The patient's response is characterized by interindividual variability without disease progression/survival modification. Objectives: We hypothesize that a therapeutic intervention may be more effective if single nucleotide polymorphisms (SNPs) are investigated. Methods: In 71 COPD patients under pulmonary rehabilitation, a small number of powerful SNPs, selected according to current literature, were analyzed; namely the glucocorticoid receptor gene NR3C1 (rs6190/rs6189/rs41423247), the glucocorticoid-induced transcript 1 gene (GLCCI1 rs37972), and the related co-chaperone FKBP5 gene (rs4713916). MDR1 rs2032582 was also evaluated. Lung function outcomes were assessed. Results: A significant association with functional outcomes, namely FEV₁ (forced expiration volume/one second) and 6MWD (six-minutes walking distance), was found for rs4713916 and weakly for rs37972. The genotype rs4713916(GA) and, in a lesser extent, the genotype rs37972(TT), were more favorable than the wild-type. Conclusions: Our study supports a possible picture of pharmacogenomic control for COPD intervention. rs4713916 and, possibly, rs37972 may be useful predictors of clinical outcome. These results may help to tailor an optimal dose for individual COPD patients based on their genetic makeup.

The value of high-resolution computed tomography (HRCT) to determine exercise ventilatory inefficiency and dynamic hyperinflation in adult patients with cystic fibrosis

Introduction

In Cystic Fibrosis (CF), exercise ventilatory inefficiency and dynamic hyperinflation (DH) cause exercise limitation and induce poor exercise tolerance. High-resolution computed tomography (HRCT) of the lung can detect pulmonary abnormalities in CF patients. We aimed to identify the determinants of exercise ventilatory inefficiency and DH using HRCT-derived metrics.

Methods

Fifty-two adult CF patients were prospectively enrolled; all participants underwent cardio-pulmonary exercise test (CPET) and HRCT. Radiological impairment was evaluated by the Brody II scoring system. Slope and intercept of the minute ventilation/CO₂ production (V’_E/V’_CO2) regression line and the ratio of inspiratory capacity/total lung capacity (IC/TLC) at rest and at peak of exercise were measured.

Results

Four groups of patients were identified based on the combination of ventilatory efficiency (Vef) or inefficiency (Vin) and the presence/absence of DH. Compared to other groups, CF adults with Vin and DH had worse functional status and higher total (T), bronchiectasis (B) and air trapping (AT) scores at HRCT. Significant correlations were found between V’_E/V’_{CO2 intercept} and V’_E/V’_{CO2 slope} (ρ − 0.455, p = 0.001) and between V’_E/V’_{CO2 intercept} and Δ inspiratory capacity (IC) (ρ − 0.334, p = 0.015). Regression analysis identified AT score (cut-off 7.9, odds ratio-OR 3.50) as the only independent predictor of Vin and T (cut-off 53.6, OR 4.98), B (cut-off 16.1, OR 4.88), airways wall thickening (AWT) (cut-off 13, OR 3.41), and mucous plugging (MP) scores (cut-off 11.7, OR 4.18) as significant predictors of DH.

Conclusion

In adult CF cohort, values of HRCT metrics are determinants of Vin (AT) and DH (T, B, AWT, MP).

Additional Effects of Nutritional Antioxidant Supplementation on Peripheral Muscle during Pulmonary Rehabilitation in COPD Patients: A Randomized Controlled Trial

Background

Skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease (COPD) is not fully reversed by exercise training. Antioxidants are critical for muscle homeostasis and adaptation to training. However, COPD patients experience antioxidant deficits that worsen after training and might impact their muscle response to training. Nutritional antioxidant supplementation in combination with pulmonary rehabilitation (PR) would further improve muscle function, oxidative stress, and PR outcomes in COPD patients.

Methods

Sixty-four COPD patients admitted to inpatient PR were randomized to receive 28 days of oral antioxidant supplementation targeting the previously observed deficits (PR antioxidant group; α-tocopherol: 30 mg/day, ascorbate: 180 mg/day, zinc gluconate: 15 mg/day, selenomethionine: 50 μg/day) or placebo (PR placebo group). PR consisted of 24 sessions of moderate-intensity exercise training. Changes in muscle endurance (primary outcome), oxidative stress, and PR outcomes were assessed.

Results

Eighty-one percent of the patients (FEV₁ = 58.9 ± 20.0%pred) showed at least one nutritional antioxidant deficit. Training improved muscle endurance in the PR placebo group (+37.4 ± 45.1%, p < 0.001), without additional increase in the PR antioxidant group (-6.6 ± 11.3%; p = 0.56). Nevertheless, supplementation increased the α-tocopherol/γ-tocopherol ratio and selenium (+58 ± 20%, p < 0.001, and +16 ± 5%, p < 0.01, respectively), muscle strength (+11 ± 3%, p < 0.001), and serum total proteins (+7 ± 2%, p < 0.001), and it tended to increase the type I fiber proportion (+32 ± 17%, p = 0.07). The prevalence of muscle weakness decreased in the PR antioxidant group only, from 30.0 to 10.7% (p < 0.05).

Conclusions

While the primary outcome was not significantly improved, COPD patients demonstrate significant improvements of secondary outcomes (muscle strength and other training-refractory outcomes), suggesting a potential “add-on” effect of the nutritional antioxidant supplementation (vitamins C and E, zinc, and selenium) during PR. This trial is registered with NCT01942889.

Efficacy of yoga, tai chi and qi gong on the main symptoms of chronic obstructive pulmonary disease: A systematic review

INTRODUCTION

The aim of this systematic review was to summarize the effects of yoga, qi gong or tai chi in COPD patients.

METHODS

Studies evaluating effects of the selected complementary therapies on lung function, dyspnea, quality of life or functional exercise capacity in COPD patients were identified and reviewed from three databases.

RESULTS

Eighteen studies were included. Six studies evaluated the effects of yoga and the others focused on tai chi or qi gong separately or combined. The duration of the programs ranged from 6 weeks to 6 months and the frequency from 2 to 7 times a week. Each session reached 30 to 90 minutes. Benefits were observed on lung function and functional exercise capacity but benefit was clearly stated neither on quality of life nor on dyspnea.

CONCLUSION

This systematic review highlights the potential of these therapies as complementary therapeutic approach in COPD patients.

A Prospective Cohort Study on the Effects of Geriatric Rehabilitation Following Acute Exacerbations of COPD

OBJECTIVES

Older patients with chronic obstructive pulmonary disease (COPD), hospitalized for an acute exacerbation, often do not receive recommended post-acute pulmonary rehabilitation. This underuse might be related to the impaired clinical and functional status of these patients, who are more likely to present with frailty, comorbidities, and disability. Having developed and implemented a geriatric rehabilitation program for these patients (GR_COPD), the primary aim of this study was to investigate the effectiveness of this program.

DESIGN AND INTERVENTION

A prospective cohort study with a 3-month follow-up period. Patients who declined the GR_COPD program were considered as controls.

SETTING AND PARTICIPANTS

The study was conducted at the pulmonary department of 2 hospitals. Patients were eligible when hospitalized as a result of an acute exacerbation of COPD and indicated for the GR_COPD program based on standardized criteria.

METHODS

Primary outcome was defined as change in disease-specific health status measured with the clinical COPD questionnaire (CCQ), secondary outcome as the exacerbation rate ratio during follow-up. To balance potential confounders between the intervention and control group, propensity score-based weighted linear regression analyses were performed.

RESULTS

Of the 158 included patients [78 (49.4%) male, mean age 70.8 (±8.1) years, mean forced expiratory volume in 1 second: 35.5 (±12.8) as % of predicted], 78 received the GR_COPD program. The results of the CCQ showed a significant and clinically relevant treatment effect of -0.56 points [95% confidence interval (CI) -0.89, -0.23; P = .001). Patients in the control group had 2.77 times more exacerbations compared with the intervention group (95% CI 2.13, 3.58; P < .001).

CONCLUSIONS/IMPLICATIONS

This study shows a clinically relevant effect of the GR_COPD program on disease-specific health status and exacerbation rate. Implementation of the program for older patients with severe COPD hospitalized for an acute exacerbation is recommended.

Peak oxygen uptake reference values for cycle ergometry for the healthy Dutch population: data from the LowLands Fitness Registry

Peak oxygen uptake (V′_O2peak) is recognised as the best expression of aerobic fitness. Therefore, it is essential that V′_O2peak reference values are accurate for interpreting a cardiopulmonary exercise test (CPET). These values are country specific and influenced by underlying biological ageing processes. They are normally stratified per paediatric and adult population, resulting in a discontinuity at the transition point between prediction equations. There are currently no age-related reference values available for the lifespan of individuals in the Dutch population. The aim of this study is to determine the best-fitting regression model for V′_O2peak in the healthy Dutch paediatric and adult populations in relation to age.

In this retrospective study, CPET cycle ergometry results of 4477 subjects without reported somatic diseases were included (907 females, age 7.9–65.0 years). Generalised additive models were employed to determine the best-fitting regression model. Cross-validation was performed against an independent dataset consisting of 3518 subjects (170 females, age 6.8–59.0 years).

An additive model was the best fitting with the largest predictive accuracy in both the primary (adjusted R²=0.57, standard error of the estimate (see)=556.50 mL·min⁻¹) and cross-validation (adjusted R²=0.57, see=473.15 mL·min⁻¹) dataset.

This study provides a robust additive regression model for V′_O2peak in the Dutch population.

Peak oxygen uptake has a nonlinear dependence on years of age in the paediatric and adult Dutch populationshttp://ow.ly/H3fH30nIjRy

"Can do" versus "do do": A Novel Concept to Better Understand Physical Functioning in Patients with Chronic Obstructive Pulmonary Disease

BACKGROUND

Physical capacity (PC) and physical activity (PA) represent associated but separate domains of physical function. It remains unknown whether this framework may support a better understanding of the impaired physical function in patients with chronic obstructive pulmonary disease (COPD). The current study had two aims: (1) to determine the distribution of patients with COPD over the PC-PA quadrants, and (2) to explore whether differences exist in clinical characteristics between these quadrants.

METHODS

In this retrospective study, PC was measured using the six-minute walk distance (6MWD), and PA was assessed with an accelerometer. Moreover, patients' clinical characteristics were obtained. Patients were divided into the following quadrants: (I) low PC (6MWD <70% predicted), low PA, using a step-defined inactivity index (<5000 steps/day, "can't do, don't do" quadrant); (II) preserved PC, low PA ("can do, don't do" quadrant); (III) low PC, preserved PA ("can't do, do do" quadrant); and (IV) preserved PC, preserved PA ("can do, do do" quadrant).

RESULTS

The distribution of the 662 COPD patients over the quadrants was as follows: "can't do, don't do": 34%; "can do, don't do": 14%; "can't do, do do": 21%; and "can do, do do": 31%. Statistically significant differences between quadrants were found for all clinical characteristics, except for educational levels.

CONCLUSIONS

This study proves the applicability of the PC-PA quadrant concept in COPD. This concept serves as a pragmatic clinical tool, that may be useful in the understanding of the impaired physical functioning in COPD patients and therefore, may improve the selection of appropriate interventions to improve physical function.

[Dyspnoea in asthma: diagnostic approach]

Dyspnoea is a cardinal symptom of asthma and an essential part of assessing control of the disease. Its intensity is variable for the same level of bronchial obstruction, which suggests the involvement of other mechanisms. Therefore, it is extremely important to characterize and measure dyspnoea in asthmatic patients because its profile can be quantitatively and qualitatively modified by disease control, comorbidities and anxiety. Hence the value of using additional tools to ACT and ACQ because the latter do not characterize nor measure specifically dyspnoea in asthma. Different tools can be used in this regard, at rest as the subjective assessment of dyspnoea by scales such as the modified Medical Research Council (mMRC), the New York Heart Association (NYHA) and the Visual Analogue Scale (VAS) or more recently using the Dyspnea-12 and the Multidimensional Dyspnea Profile (MDP) questionnaire, which assesses the sensory and affective dimensions of dyspnoea; and during exercise testing such as the "modified" Borg scale, graduated from 0 to 10, or the VAS. Among the factors contributing to dyspnoea in asthmatic patients, probably bronchial obstruction, increased airway resistance and dynamic hyperinflation play an important role. Despite this, the asthmatic patient's description of dyspnoea may be masked by hyperventilation syndrome or other comorbidities that can easily be detected and treated through educational programs and targeted therapies.

Outpatient pulmonary rehabilitation for severe asthma with fixed airway obstruction: Comparison with COPD

Background: The benefit of exercise has been demonstrated in asthma, but the role of pulmonary rehabilitation (PR) in people with severe asthma, especially with airway obstruction, has been less investigated. The activity limitation mechanisms differ in asthma and COPD, so the effect of a PR program not specific to asthma is unclear. Methods: We retrospectively compared the effect of an ambulatory PR program in nonsmoking patients with severe asthma and airway obstruction (FEV1/FVC ratio <70% and FEV1 < 80% measured twice, not under an exacerbation) and sex-, age-, FEV1-, and BMI-matched COPD controls. Results: We included 29 patients, each with asthma and COPD. Airway obstruction was moderate (median FEV1 57% [44-64]). VO₂ at peak was higher for asthma than COPD patients (19.0 [15.7-22.2] vs 16.1 [15.3-19.6] ml.min^-1.kg^-1, p = 0.05). After PR, asthma and COPD groups showed a significant and similar increase in constant work cycling test of 378 [114-831] s and 377 [246-702] s. Changes in Hospital Anxiety and Depression Scale (HAD) total score were similar (-2.5 [-7.0 to 0.0] vs -2.0 [-5.0 to 2.0], p > 0.05). Quality of life on the St. George's Respiratory Questionnaire (SGRQ) was significantly improved in both groups (-14.0 [-17.7 to -2.0], p < 0.005 and -8.3 [-13.0 to -3.6], p < 0.0001). Conclusion: Outpatient PR is feasible and well tolerated in patients with severe asthma with fixed airway obstruction. A nondedicated program strongly improves HAD and SGRQ scores and constant work-rate sub-maximal cycling, with similar amplitude as with COPD.

Minimal clinically important difference of 3-minute chair rise test and the DIRECT questionnaire after pulmonary rehabilitation in COPD patients

BACKGROUND

The 3-minute chair rise test (3-minute CRT) and the Disability Related to COPD Tool (DIRECT) are two reproducible and valid short tests that can assess the benefit of pulmonary rehabilitation (PR) in terms of functional capacity and dyspnea in everyday activities.

METHODS

We determined the minimal clinically important difference (MCID) of the DIRECT questionnaire and 3-minute CRT using distribution methods and anchor encroaches with a panel of eight standard tests in a cohort of 116 COPD patients who completed a PR program in real-life settings.

RESULTS

The estimated MCID for the 3-minute CRT and DIRECT scores was five repetitions and two units, respectively, using separate and combined independent anchors. The all-patient (body mass index-obstruction-dyspnea-exercise [BODE] scores 0-7), BODE 0-2 (n=42), and BODE 3-4 (n=50) groups showed improvements greater than the MCID in most tests and questionnaires used. In contrast, the BODE 5-7 group (n=24) showed improvements greater than MCID in only the 3-minute CRT, 6-minute walk test, endurance exercise test, and DIRECT questionnaire.

DISCUSSION AND CONCLUSION

This study demonstrates that the short and simple DIRECT questionnaire and 3-minute CRT are responsive to capture the beneficial effects of a PR program in COPD patients, including those with severe disease.

TRIAL REGISTRATION NUMBER

NCT03286660.

Intermittent Use of Portable NIV Increases Exercise Tolerance in COPD: A Randomised, Cross-Over Trial

During exercise, non-invasive ventilation (NIV) prolongs endurance in chronic obstructive pulmonary disease (COPD), but routine use is impractical. The VitaBreath device provides portable NIV (pNIV); however, it can only be used during recovery. We assessed the effect of pNIV compared to pursed lip breathing (PLB) on exercise tolerance. Twenty-four COPD patients were randomised to a high-intensity (HI: 2-min at 80% peak work rate (WRpeak) alternated with 2-min recovery; n = 13), or a moderate-intensity (MOD: 6-min at 60% WRpeak alternated with 2-min recovery; n = 11) protocol, and within these groups two tests were performed using pNIV and PLB during recovery in balanced order. Upon completion, patients were provided with pNIV; use over 12 weeks was assessed. Compared to PLB, pNIV increased exercise tolerance (HI: by 5.2 ± 6.0 min; MOD: by 5.8 ± 6.7 min) (p < 0.05). With pNIV, mean inspiratory capacity increased and breathlessness decreased by clinically meaningful margins during recovery compared to the end of exercise (HI: by 140 ± 110 mL and 1.2 ± 1.7; MOD: by 170 ± 80 mL and 1.0 ± 0.7). At 12 weeks, patients reported that pNIV reduced anxiety (median: 7.5/10 versus 4/10, p = 0.001) and recovery time from breathlessness (17/24 patients; p = 0.002); 23/24 used the device at least weekly. pNIV increased exercise tolerance by reducing dynamic hyperinflation and breathlessness in COPD patients.

Effect of 12 weeks of once-daily tiotropium/olodaterol on exercise endurance during constant work-rate cycling and endurance shuttle walking in chronic obstructive pulmonary disease

Background:

The TORRACTO^® study evaluated the effects of tiotropium/olodaterol versus placebo on endurance time during constant work-rate cycling and constant speed shuttle walking in patients with chronic obstructive pulmonary disease (COPD) after 12 weeks of treatment.

Methods:

The effects of once-daily tiotropium/olodaterol (2.5/5 and 5/5 μg) on endurance time during constant work-rate cycle ergometry (CWRCE) after 6 and 12 weeks of treatment were compared with placebo in patients with COPD in a randomized, double-blind, placebo-controlled, parallel-group clinical trial. Endurance time during the endurance shuttle walk test (ESWT) after 6 and 12 weeks of treatment was also evaluated in a subset of patients.

Results:

A total of 404 patients received treatment, with 165 participating in the ESWT substudy. A statistically significant improvement in endurance time during CWRCE was observed after 12 weeks (primary endpoint) with tiotropium/olodaterol 5/5 µg [14% (p = 0.02)] but not with tiotropium/olodaterol 2.5/5 µg [9% (p = 0.14)] versus placebo. In the ESWT substudy, a trend to improvement in endurance time during ESWT after 12 weeks (key secondary endpoint) was observed with tiotropium/olodaterol 5/5 µg [21% (p = 0.055)] and tiotropium/olodaterol 2.5/5 µg [21% (p = 0.056)] versus placebo.

Conclusion:

Tiotropium/olodaterol 5/5 µg improved endurance time during cycle ergometry versus placebo, with a strong tendency to also improve walking endurance time.

[ClinicalTrials.gov identifier: NCT01525615.]

The once-daily fixed-dose combination of olodaterol and tiotropium in the management of COPD: current evidence and future prospects

Long-acting bronchodilators are the cornerstone of pharmacologic treatment of chronic obstructive pulmonary disease (COPD). Spiolto® or Stiolto® is a fixed-dose combination (FDC) containing two long-acting bronchodilators, the long-acting muscarinic receptor antagonist tiotropium (TIO) and the long-acting β2-adrenoceptor agonist olodaterol (OLO), formulated in the Respimat® Soft Mist™ inhaler. A total of 13 large, multicentre studies of up to 52 weeks' duration have documented its efficacy in more than 15,000 patients with COPD. TIO/OLO 5/5 µg FDC significantly increases pulmonary function compared with placebo and its respective constituent mono-components TIO 5 µg and OLO 5 µg. TIO/OLO 5/5 µg also results in statistically and clinically significant improvements in patient-reported outcomes, such as dyspnoea, use of rescue medication, and health status. Addition of OLO 5 µg to TIO 5 µg reduces the rate of moderate-to-severe exacerbations by approximately 10%. Compared with placebo and TIO 5 µg, TIO/OLO 5/5 µg significantly improves exercise capacity (e.g. endurance time) and physical activity, the latter increase being reached by a unique combination behavioural modification intervention, dual bronchodilatation and exercise training. Overall, the likelihood for patients to experience a clinically significant benefit is higher with TIO/OLO 5/5 µg than with its constituent mono-components, which usually yield smaller improvements which do not always reach statistical significance, compared with baseline or placebo. This supports the early introduction of TIO/OLO 5/5 µg in the management of patients with symptomatic COPD.

The Role of Cardiopulmonary Exercise Testing (CPET) in Pulmonary Rehabilitation (PR) of Chronic Obstructive Pulmonary Disease (COPD) Patients

Chronic obstructive pulmonary disease (COPD) is a common multisystem inflammatory disease with ramifications involving essentially all organ systems. Pulmonary rehabilitation is a comprehensive program designed to prevent and mitigate these disparate systemic effects and improve patient quality of life, functional status, and social functioning. Although initial patient assessment is a prominent component of any pulmonary rehabilitation (PR) program, cardiopulmonary exercise testing (CPET) is not regularly performed as a screening physiologic test prior to PR in COPD patients. Further, CPET is not often used to assess or document the improvement in exercise capacity related to completion of PR. In this review we will describe the classic physiologic abnormalities related to COPD on CPET parameters, the role of CPET in Risk Stratification/Safety prior to PR, the physiologic changes that occur in CPET parameters with PR, and the literature regarding the use of CPET to assess PR results. Finally, we will compare CPET to 6MW in COPD PR, the common minimal clinically important difference (MCID) is associated with CPET, and the potential future roles of CPET in PR and Research.

Repeatability and Meaningful Change of CPET Parameters in Healthy Subjects

INTRODUCTION/PURPOSE

Cardiopulmonary exercise testing (CPET) plays an important role in clinical medicine and research. Repeatability of CPET parameters has not been well characterized, but is important to assess variability and determine if there have been meaningful changes in a given CPET parameter.

METHODS

We recruited 45 healthy subjects and performed two symptom-limited CPET within 30 d using a cycle ergometer. Differences in relevant CPET parameters between CPET-1 and CPET-2 were assessed using a paired t-test. Coefficient of variation (CoV) and Bland-Altman plots are reported. Factors that may be associated with variability were analyzed (sex, age, time of day, fitness level). The coefficient of repeatability was calculated for peak oxygen consumption (V˙O2) and V˙O2 at lactate threshold (LT) to establish a 95% threshold for meaningful change.

RESULTS

There were no significant differences between tests in the parameters reported. Specifically, we found overall low CoV in peak V˙O2 (4.9%), V˙O2@LT (10.4%), peak O2 pulse (4.6%), peak minute ventilation (V˙E; 7.4%), V˙E/V˙CO2@LT (4.0%), and V˙E/V˙O2@LT (4.8%). The CoV for peak respiratory exchange ratio@LT was significantly affected by diurnal factors; age, sex, and fitness level did not affect variability. The 95% threshold for meaningful change was 0.540 L·min in peak V˙O2 and 0.520 L·min in V˙O2@LT.

CONCLUSIONS

Repeatability of CPET parameters is generally higher than previously reported. There were no significant differences in variability related to sex, age, and fitness level; diurnal factors had a limited effect. The threshold for meaningful change in peak V˙O2 and for V˙O2@LT should be considered when gauging a response to therapies or training.

Residual high intrapulmonary shunt fraction limits exercise capacity in patients treated with balloon pulmonary angioplasty

Balloon pulmonary angioplasty (BPA) has emerged as a new treatment strategy for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Improvements in hemodynamic parameters after BPA have been reported, but some patients continue to suffer from reduced exercise tolerance even after the normalization of hemodynamic parameters following BPA. As the amelioration of hemodynamic parameters is reportedly achieved via BPA, we hypothesized that the limiting factors for exercise tolerance in these patients are related to respiratory function. Therefore, we investigated the associations between respiratory function and exercise tolerance, and the mechanisms underlying respiratory dysfunction in patients after BPA. We analyzed 62 patients with CTEPH who underwent 1-year follow-up after BPA. Predictors for reduced exercise tolerance after BPA determined with six-minute walk test were sought from pulmonary hemodynamic and respiratory parameters using logistic regression analysis. After multivariate adjustments, high mean right atrium pressure (mRAP) and high alveolar-arterial oxygen gradient (A-aDO₂) were significant predictors for reduced exercise tolerance. Next, we analyzed factors associated with high A-aDO2. Among the pathophysiological causes of high A-aDO2, including ventilation, diffusing capacity, and low ventilation-perfusion ratio, only low ventilation-perfusion ratio caused by high intrapulmonary shunt fraction was associated with high A-aDO₂. Impaired oxygenation due to residual high intrapulmonary shunt fraction was associated with reduced exercise tolerance in patients with CTEPH, after receiving BPA.

Effects of high intensity interval training on exercise capacity in people with cystic fibrosis: study protocol for a randomised controlled trial

BACKGROUND

In people with cystic fibrosis (CF), higher exercise capacity is associated with better health-related quality of life (HRQoL), reduced risk of hospitalisation for a respiratory infection and survival. Therefore, optimisation of exercise capacity is an important treatment goal. The Australian and New Zealand clinical practice guidelines recommend that people with CF complete 30 to 60 min of moderate intensity aerobic exercise on most days of the week. This recommendation can be difficult to achieve by people with CF because of time constraints, and intolerable breathlessness and muscle fatigue during continuous exercise. In contrast, a low-volume, high intensity interval training (HIIT) program may be a more achievable and efficient training method to improve exercise capacity in people with CF.

METHODS

A randomised controlled trial will be undertaken. Forty people with CF (aged ≥15 years) will be randomly allocated, on a 1:1 ratio, to either the experimental or control group. Regardless of their group allocation, all participants will be asked to continue with their usual daily treatment for the study duration. Those in the experimental group will complete 8 weeks of thrice weekly HIIT on a cycle ergometer. Those in the control group will receive weekly contact with the investigators. The primary outcome of this study is exercise capacity. Secondary outcomes are HRQoL, exercise self-efficacy, feelings of anxiety, depression and enjoyment. These outcomes will be recorded at baseline (i.e. prior to randomisation) and following the 8-week intervention period. The study will also report other outcomes of the HIIT program (cardiovascular responses, symptom response, post-exercise muscle soreness and tolerance) and behaviour change techniques such as reinforcement, feedback and goal setting, used during the HIIT program.

DISCUSSION

This study will determine the effects of 8-weeks of supervised, low-volume HIIT, completed on a cycle ergometer on measures of exercise capacity, HRQoL, exercise self-efficacy, feelings of anxiety, depression and enjoyment. If effective, this type of training could be an attractive alternative to traditional continuous training because it may be more achievable and time efficient.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry (ANZCTR):12617001271392 (04/09/2017).

Efficiency of the home cardiac rehabilitation program for adults with complex congenital heart disease

OBJECTIVE

We aimed to study the efficiency and safety of once-a-week outpatient rehabilitation followed by home program with tele-monitoring in patients with complex cyanotic congenital heart disease.

DESIGN

Prospective nonrandomized study.

METHOD

Patients who have been diagnosed either Eisenmenger's syndrome or inoperable complex cyanotic heart disease and able to attend 12-week cardiac rehabilitation program were included. Training with treadmill walking and bicycling under supervision at cardiac rehabilitation unit once-a-week in the first 6 weeks followed by home-based exercise program (bicycle and walking) with a target at 40%-70% of maximum heart rate (HRmax) at pretraining peak exercise for another 6 weeks was performed in the intervention group. Video and telephone calls were scheduled for evaluation of compliance and complication. Data from cardiopulmonary exercise testing (CPET) on cycle ergometry including peak oxygen consumption (peakVO₂ ), oxygen pulse (O₂ pulse), ventilatory equivalent for carbon dioxide (VE/CO₂ at anaerobic threshold), constant work-rate endurance time (CWRET) at 75% of peak VO₂ , and 6-minute walk distance (6MWD) were compared between baseline and after training by paired t test.

RESULT

Of the 400 patients in our adult congenital heart disease clinic, 60 patients met the inclusion criteria. Eleven patients who could follow program regularly were assigned home program. There was a statistically significant improvement of CWRET, O₂ pulse, and 6MWD after finishing the program (P = .003, .039, and .001, respectively). The mean difference of 6MWD change in the home-program group was significantly higher than in the control group (69.3 ± 47.9 meters vs. 4.1 ± 43.4 meters, P = .003). No serious adverse outcomes were reported during home training.

CONCLUSION

Once-a-week outpatient hospital-based exercise program followed by supervised home-based exercise program showed a significant benefit in improvement of exercise capacity in adults with complex cyanotic congenital heart disease without serious adverse outcomes.

Pulmonary Rehabilitation: Where We've Succeeded and Where We've Failed

Pulmonary rehabilitation has been established as the standard of care for patients with symptomatic chronic obstructive pulmonary disease (COPD). Benefits include improvements in exercise tolerance, dyspnoea and quality of life; magnitude of benefit is generally greater than for any other COPD therapy. A wide range of professional organizations and standards documents have recommended pulmonary rehabilitation; benefits accrue across the spectrum of disease severity. However, pulmonary rehabilitation is provided to only a tiny fraction of those chronic obstructive pulmonary disease (COPD) patients who would benefit. International estimates posit that only 1-2% of COPD patients receive pulmonary rehabilitation. In contrast, other COPD therapies, bronchodilators and oxygen therapy in particular, are much more widely available. The costs of pulmonary rehabilitation should not be a major barrier, as costs are comparable to other therapies. In seeking strategies to increase pulmonary rehabilitation availability, it can be argued that a demonstration of a life prolongation benefit would be of great help. Therapies that improve survival have a high priority for patients, for their health care providers and for payers. A well-designed survival study has never been performed. Although efforts are underway to organize such a trial, even in a best-case scenario it will be a number of years before the results are available.

Cardiopulmonary exercise testing with supramaximal verification produces a safe and valid assessment of V̇o2max in people with cystic fibrosis: a retrospective analysis

The validity and safety of using supramaximal verification (S_max) to confirm a maximal effort during cardiopulmonary exercise testing (CPET) in people with cystic fibrosis (CF) and/or those with severe disease has been questioned. Therefore, this study aimed to investigate these concerns in children, adolescents, and adults with mild-to-severe CF lung disease. Retrospective analysis of 17 pediatric and 28 adult participants with CF [age range: 9.2-62.9 y; forced expiratory volume in 1 s: 66.7% (range: 29.9%-102.3%); 30 men] who completed a routine ramp-incremental cycling test to determine peak oxygen uptake (V̇o_2peak) was studied. Maximal oxygen uptake (V̇o_2max) was subsequently confirmed by S_max at 110% of peak power output. All participants satisfied the criteria to verify a maximal effort during CPET. However, S_max-V̇o_2peak exceeded ramp-V̇o_2peak in 3/14 (21.4%) of pediatric and 6/28 (21.4%) adult exercise tests. A valid measurement of V̇o_2max was attained in 85.7% of pediatric and 96.4% of adult exercise tests, as S_max-V̇o_2peak did not exceed ramp-V̇o_2peak by >9%. Adults ( n = 9) experienced a ≥5% reduction in arterial O₂ saturation during CPET, 4 during both the ramp and S_max, 3 during only the ramp, and 2 during only S_max. S_max did not significantly worsen perceived breathing effort, chest tightness, throat narrowing, or exertion compared with ramp-incremental testing. Given the clinical importance of aerobic fitness in people with CF, incorporating S_max is recommended to provide a safe and valid measure of V̇o_2max in children, adolescents, and adults who span the spectrum of CF disease severity. NEW & NOTEWORTHY Incorporating supramaximal verification into cardiopulmonary exercise testing protocols did not increase the frequency of adverse events or perceived discomfort versus a single-phase incremental exercise test in people with mild-to-severe cystic fibrosis. Furthermore, a valid measure of maximal oxygen uptake (V̇o_2max) was obtained from 85.7% of pediatric and 96.4% of adult exercise tests, whereas peak oxygen uptake underestimated aerobic fitness in comparison with V̇o_2max in 21.4% of cases (by up to 24.4%).