Change in V˙O2peak in Response to Aerobic Exercise Training and the Relationship With Exercise Prescription in People With COPD: A Systematic Review and Meta-analysis

Prevalence and prognostic importance of exercise limitation and physical inactivity in COPD

Exercise limitation and physical inactivity are separate, but related constructs. Both are commonly present in individuals with COPD, contribute to disease burden over and above the respiratory impairments, and are independently predictive of adverse outcomes. Because of this, clinicians should consider assessing these variables in their patients with COPD. Field tests of exercise performance such as the 6-min walk test and the incremental and endurance shuttle walk tests require limited additional resources, and results correlate with negative outcomes. Laboratory measures of exercise performance using a treadmill or cycle ergometer assess exercise capacity, provide prognostic information and have the advantage of explaining physiological mechanisms (and their interactions) underpinning exercise limitation. Limitations in exercise capacity (i.e. "cannot do") and physical inactivity (i.e. "do not do") are both associated with mortality; exercise limitation appears to be the more important driver of this outcome.

Quality of aerobic training description and its relation to intervention efficacy in chronic obstructive pulmonary disease trials: study protocol for a systematic review, meta-analysis and meta-regression

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a major global health concern, characterised by ventilatory constraints, decreased cardiovascular fitness and reduced limb muscle function, profoundly affecting patients' quality of life. Aerobic training plays a crucial role in the treatment of COPD, but the variability in methodologies and incomplete reporting of key components in aerobic training trials limits the assessment of their effectiveness. This systematic review aims to critically evaluate the application of training principles and reporting of key components in aerobic training trials in randomised controlled trials (RCTs) in the COPD literature.

METHODS AND ANALYSIS

The protocol adheres to the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocol guidelines. The review will include RCTs utilising aerobic training in individuals with COPD. A comprehensive search, following a predefined search strategy will identify studies published from 2007 to 2024 in English from MEDLINE, Embase, CINAHL, CENTRAL and PEDro. Studies including people with COPD and any aerobic training intervention will be included. Two reviewers will independently screen abstracts and titles for inclusion. Two reviewers will independently conduct the screening of full-text documents and data extraction. Study quality will be assessed using the Tool for the assESsment of sTudy quality and bias in Exercise, specifically developed for exercise training studies. The certainty of the evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. A systematic synthesis will be provided, with meta-analyses and meta-regression when appropriate.

ETHICS AND DISSEMINATION

As this review will involve the analysis of published data, ethical approval is not required. The findings of this review will be disseminated through peer-reviewed publications and conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42021247343.

Association Between Regular Moderate to Vigorous Physical Activity Initiation Following COPD Diagnosis and Mortality: An Emulated Target Trial Using Nationwide Cohort Data

BACKGROUND

Moderate to vigorous physical activity (MVPA) in patients with COPD affects their overall health outcomes, including symptom relief and improved quality of life. However, the magnitude of the effect of MVPA initiation on real-world clinical outcomes has not been well investigated.

RESEARCH QUESTION

How does MVPA initiation affect mortality and severe exacerbation in patients who have not engaged in MVPA prior to COPD diagnosis?

STUDY DESIGN AND METHODS

This study included patients with COPD aged ≥ 40 years who were not performing MVPA prior to COPD diagnosis and who had at least one health screening visit prior to and following their COPD diagnosis between January 1, 2010, and December 31, 2018. The main exposure was MVPA, defined as vigorous aerobic exercise > 20 min per day on ≥ 3 days per week or moderate aerobic exercise > 30 min per day on ≥ 5 days per week. The primary end point was all-cause mortality, and the secondary end point was initial severe exacerbation as the time to event following COPD diagnosis.

RESULTS

In total, 110,097 person-trials were included (27,564 MVPA increases and 82,533 control groups). No differences were observed between the covariates following matching. The adjusted hazards ratio of all-cause mortality for the MVPA group compared with the control group was 0.84 (95% CI, 0.79-0.89). In the subgroup analysis, patients aged > 65 years, female patients, those who had never smoked, and patients with a higher Charlson Comorbidity Index score displayed a stronger effect of MVPA on reducing mortality than younger male patients, those who had ever smoked, and patients with a lower Charlson Comorbidity Index score (Pinteraction < .05). The fully adjusted hazards ratio for the risk of severe exacerbation (MVPA group vs control) was 0.90 (95% CI, 0.87-0.94).

INTERPRETATION

Initiation of MVPA can potentially reduce mortality and severe exacerbations in patients with COPD, although personalized interventions and further clinical trials are necessary.

Laryngeal widening and adequate ventilation by expiratory pressure load training improve aerobic capacity in COPD: a randomised controlled trial

RATIONALE

Despite strategies acting on peripheral airway obstruction in chronic obstructive pulmonary disease (COPD), exercise intolerance remains inadequately improved. We hypothesised that laryngeal narrowing is a potential treatment target of expiratory pressure load training (EPT) to improve exercise intolerance in COPD.

METHODS

The effect of 3-month EPT was assessed in 47 patients with COPD divided into Global Initiative for Chronic Obstructive Lung Disease (GOLD) mild-to-moderate (I-II) and severe-to-very severe (III-IV), randomly allocating 1:1 to EPT or control groups. The primary outcome was endurance time in the constant work rate exercise test in GOLD III-IV patients.

RESULTS

Compared with controls, EPT increased: (1) endurance time, with estimated treatment effect: +703 (95% CI: 379 to 1031) s, p=0.0008 (GOLD I-II); +390 (95% CI: 205 to 574) s, p=0.0006 (GOLD III-IV); (2) peak oxygen uptake (p=0.0086 in GOLD I-II; p=0.0004 in GOLD III-IV); (3) glottic dilatation ratio at maximum collapse on laryngoscopy in the submaximal exercise (p=0.0062 in GOLD I-II; p=0.0001 in GOLD III-IV); and (4) the inflection point of expiratory tidal volume relative to minute ventilation during the incremental exercise (p=0.0015 in GOLD I-II; p=0.0075 in GOLD III-IV). Across GOLD grades, the responses of glottic dilatation ratio at maximum collapse and the expiratory tidal volume at the inflection point were selected as more influential variables correlating with the improvement in peak oxygen uptake and endurance time, respectively.

CONCLUSION

These results show that EPT improved aerobic capacity and endurance time with larger laryngeal widening and adequate ventilation despite advanced COPD.

TRIAL REGISTRATION NUMBER

UMIN000041250.

Effect of aerobic exercise training on pulse wave velocity in adults with and without long-term conditions: a systematic review and meta-analysis

RATIONALE

There is conflicting evidence whether aerobic exercise training (AET) reduces pulse wave velocity (PWV) in adults with and without long-term conditions (LTCs).

OBJECTIVE

To explore whether PWV improves with AET in adults with and without LTC, to quantify the magnitude of any effect and understand the influence of the exercise prescription.

DATA SOURCES

CENTRAL, MEDLINE and EMBASE were among the databases searched.

ELIGIBILITY CRITERIA

We included studies with a PWV measurement before and after supervised AET of at least 3 weeks duration. Exclusion criteria included resistance exercise and alternative measures of arterial stiffness.

DESIGN

Controlled trials were included in a random effects meta-analysis to explore the effect of AET on PWV. Uncontrolled studies were included in a secondary meta-analysis and meta-regression exploring the effect of patient and programme factors on change in PWV. The relevant risk of bias tool was used for each study design.

RESULTS

79 studies (n=3729) were included: 35 controlled studies (21 randomised control trials (RCT) (n=1240) and 12 non-RCT (n=463)) and 44 uncontrolled (n=2026). In the controlled meta- analysis, PWV was significantly reduced following AET (mean (SD) 11 (7) weeks) in adults with and without LTC (mean difference -0.63; 95% CI -0.82 to -0.44; p<0.0001). PWV was similarly reduced between adults with and without LTC (p<0.001). Age, but not specific programme factors, was inversely associated with a reduction in PWV -0.010 (-0.020 to -0.010) m/s, p<0.001.

DISCUSSION

Short-term AET similarly reduces PWV in adults with and without LTC. Whether this effect is sustained and the clinical implications require further investigation.

Clinical effect of aerobic exercise training in chronic obstructive pulmonary disease: A retrospective study

Aerobic exercise training is a kind of pulmonary rehabilitation for lung diseases. This was a retrospective study to assess the efficacy of aerobic exercise training in chronic obstructive pulmonary disease (COPD) at a stable stage. A total of one hundred and fifty-six stable COPD patients who had accepted self-education only or self-education combined with an aerobic exercise training between January 2017 to January 2019 were reviewed retrospectively. A total of 79 patients who had received self-education combined with an aerobic exercise training schedule comprised the aerobic exercise training group (AET group) and 77 patients who had received self-education only were regarded as the education group (EDU group). The acute incidence rate in AET group was 7.6% better than that in EDU group 20.7% (P < .05). The AET group patients expressed higher levels of 6 minutes walking distance (6MWD) (P < .05) and better evaluations of both lung function (P < .05) and T lymphocyte immune response (P < .05), as well as significantly decreased chronic obstructive pulmonary disease assessment test (CAT) scores and modified British medical research council (mMRC) grades (P < .05). Patients in EDU group did not report any changes in any of these characteristics. The aerobic exercise training intervention contributed to an increasing in 6MWD and decrease in CAT scores and mMRC grades, as well as improving the T lymphocyte immune response in stable COPD patients.

Understanding the effectiveness of different exercise training programme designs on V̇O2peak in COPD: a component network meta-analysis

Pulmonary rehabilitation programmes including aerobic training improve cardiorespiratory fitness in patients with COPD, but the optimal programme design is unclear. We used random effects additive component network meta-analysis to investigate the relative effectiveness of different programme components on fitness measured by V̇O2peak in COPD. The included 59 studies involving 2191 participants demonstrated that V̇O2peak increased after aerobic training of at least moderate intensity with the greatest improvement seen following high intensity training. Lower limb aerobic training (SMD 0.56 95% CI 0.32;0.81, intervention arms=86) and the addition of non-invasive ventilation (SMD 0.55 95% CI 0.04;1.06, intervention arms=4) appeared to offer additional benefit but there was limited evidence for effectiveness of other exercise and non-exercise components.

Pulmonary rehabilitation and physical interventions

Pulmonary rehabilitation has established a status of evidence-based therapy for patients with symptomatic COPD in the stable phase and after acute exacerbations. Rehabilitation should have the possibility of including different disciplines and be offered in several formats and lines of healthcare. This review focusses on the cornerstone intervention, exercise training, and how training interventions can be adapted to the limitations of patients. These adaptations may lead to altered cardiovascular or muscular training effects and/or may improve movement efficiency. Optimising pharmacotherapy (not the focus of this review) and oxygen supplements, whole-body low- and high-intensity training or interval training, and resistance (or neuromuscular electrical stimulation) training are important training modalities for these patients in order to accommodate cardiovascular and ventilatory impairments. Inspiratory muscle training and whole-body vibration may also be worthwhile interventions in selected patients. Patients with stable but symptomatic COPD, those who have suffered exacerbations and patients waiting for or who have received lung volume reduction or lung transplantation are good candidates. The future surely holds promise to further personalise exercise training interventions and to tailor the format of rehabilitation to the individual patient's needs and preferences.

Regulation of whole-transcriptome sequencing expression in COPD after personalized precise exercise training: a pilot study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is one of the world's leading causes of death and a major chronic respiratory disease. Aerobic exercise, the cornerstone of pulmonary rehabilitation, improves prognosis of COPD patients; however, few studies have comprehensively examined the changes in RNA transcript levels and the crosstalk between various transcripts in this context. This study identified the expression of RNA transcripts in COPD patients who engaged in aerobic exercise training for 12 weeks, and further constructions of the possible RNAs networks were made.

METHODS

Peripheral blood samples for all four COPD patients who benefited from 12 weeks of PR were collected pre- and post-aerobic exercises and evaluated for the expression of mRNA, miRNA, lncRNA, and circRNA with high-throughput RNA sequencing followed by GEO date validation. In addition, enrichment analyses were conducted on different expressed mRNAs. LncRNA-mRNA and circRNA-mRNA coexpression networks, as well as lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA competing expression networks (ceRNAs) in COPD were constructed.

RESULTS

We identified and analyzed the differentially expressed mRNAs and noncoding RNAs in the peripheral blood of COPD patients' post-exercise. Eighty-six mRNAs, 570 lncRNAs, 8 miRNAs, and 2087 circRNAs were differentially expressed. Direct function enrichment analysis and Gene Set Variation Analysis showed that differentially expressed RNAs(DE-RNAs) correlated with several critical biological processes such as chemotaxis, DNA replication, anti-infection humoral response, oxidative phosphorylation, and immunometabolism, which might affect the progression of COPD. Some DE-RNAs were validated by Geo databases and RT-PCR, and the results were highly correlated with RNA sequencing. We constructed ceRNA networks of DE-RNAs in COPD.

CONCLUSIONS

The systematic understanding of the impact of aerobic exercise on COPD was achieved using transcriptomic profiling. This research offers a number of potential candidates for clarifying the regulatory mechanisms that exercise has on COPD, which could ultimately help in understanding the pathophysiology of COPD.

A systematic review of exercise studies for individuals hospitalized with an acute exacerbation of chronic obstructive pulmonary disease: Focus on the principles of exercise training

BACKGROUND

For exercise interventions to be effectively reproduced or applied in a "real world" clinical setting, clinical trials must thoroughly document all components of the exercise prescription and ensure that participants adhere to each component. However, previous reviews have not critically examined the quality of exercise prescription of inpatient Pulmonary Rehabilitation (PR) programs.

OBJECTIVE

The objectives of this review were to evaluate the (a) application of the principles of exercise training, (b) reporting of the frequency, intensity, time and type (FITT) components of exercise prescription, and (c) reporting of patient's adherence to the FITT components in intervention studies for patients admitted to hospital for an acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

Relevant scientific databases were searched for randomized controlled trials (RCTs) that compared in-hospital PR with usual care for people hospitalized with AECOPD. Title and abstract followed by full-text screening were conducted independently by two reviewers. Data were extracted and synthesized to evaluate the application of the principles of exercise training and the reporting/adherence of the FITT components.

RESULTS

Twenty-seven RCTs were included. Only two applied all principles of exercise training. Specificity was applied by 70%, progression by 48%, overload by 37%, initial values by 89% and diminishing returns and reversibility by 37% of trials. Ten trials adequately reported all FITT components. Frequency and type were the components most reported (85% and 81%, respectively), while intensity was less frequently reported (52%). Only three trials reported on the patient's adherence to all four components.

CONCLUSIONS

Studies have not adequately reported the exercise prescription in accordance with the principles of exercise training nor reported all the FITT components of the exercise prescription and patient's adherence to them. Therefore, interpretation of the current literature is limited and information for developing exercise prescriptions to individuals hospitalized with an AECOPD is lacking.

Greater exercise tolerance in COPD during acute intermittent compared to continuous shuttle walking protocols: A proof-of-concept study

Objectives: Ground-based walking is a simple training modality which would suit pulmonary rehabilitation (PR) settings with limited access to specialist equipment. Patients with COPD are, however, unable to walk uninterruptedly at a relatively fast walking pace to optimise training benefits. We compared an intermittent (IntSW) to a continuous (CSW) shuttle walking protocol.Methods: In 14 COPD patients (mean ± SD. FEV₁: 45 ± 21% predicted) we measured walking distance, cardiac output (CO), arterial oxygen saturation (SpO₂), and symptoms during (a) an IntSW protocol, consisting of 1-min walking alternating with 1-min rest, and (b) a CSW protocol, both sustained at 85% of predicted VO₂ peak to the limit of tolerance (Tlim).Results: Median (IQR) distance was greater (p = 0.001) during the IntSW protocol (735 (375-1107) m) than the CSW protocol (190 (117-360) m). At iso-distance (distance at Tlim during CSW) the IntSW compared to the CSW protocol was associated with lower CO (8.6 ± 2.6 vs 10.3 ± 3.7 L/min; p = 0.013), greater SpO₂ (92 ± 6% versus 90 ± 7%; p = 0.002), and lower symptoms of dyspnoea (2.8 ± 1.3 vs 4.9 ± 1.4; p = 0.001) and leg discomfort (2.3 ± 1.7 vs 4.2 ± 2.2; p = 0.001). At Tlim symptoms of dyspnoea and leg discomfort did not differ between the IntSW (4.4 ± 1.9 and 3.6 ± 2.1, respectively) and the CSW protocol.Conclusions: The IntSW protocol may provide important clinical benefits during exercise training in the PR settings because it allows greater work outputs compared to the CSW.

Financial Burden and Shortage of Respiratory Rehabilitation for SARS-CoV-2 Survivors: The Next Step of the Pandemic?

We read with great enthusiasm the recent article by Daynes et al [...]

Comparison of heart rates at fixed percentages and the ventilatory thresholds in patients with interstitial lung disease

Heart rate (HR) responses to maximal exercise are commonly used for the prescription of training intensities in pulmonary rehabilitation. Those intensities are usually based on fixed percentages of peak HR (HRpeak), heart rate reserve (HRR), or peak work load (Wpeak), and rarely on HRs at the individual ventilatory thresholds (VT1 and VT2) derived from cardiopulmonary exercise testing (CPET). For patients suffering from interstitial lung disease (ILD), data on cardiorespiratory responses to CPET are scarce. Thus, the aim of this study was to record cardiorespiratory responses to CPET and to compare fixed HR percentages with HRs at VT1 and VT2 in ILD patients. A total of 120 subjects, 80 ILD patients and 40 healthy controls, underwent a symptom‐limited CPET. From the ILD patient, 32 suffered from idiopathic pulmonary fibrosis (IPF), 37 from connective tissue disease (CTD), and 11 from sarcoidosis. HRs at fixed percentages, that is, at 70%HRpeak, at 70%Wpeak, and at 60%HRR were significantly lower in the ILD patients compared with the control group (p‐values: 0.001, 0.044, and 0.011). Large percentages of HR values at 70%Wpeak and 60%HRR ranged between the HRs at VT1 and VT2 in ILD subgroups and controls as well. HRs at 70%HRpeak were lower than HRs at VT1 in 66% of the IPF patients, 54% of the CTD patients, and 55% of patients with sarcoidosis compared with 18% in the control group. Our findings demonstrate a considerable scattering of fixed HR percentages compared with HRs at the individual VTs derived from CPET in ILD patients. These findings may provide valuable information for the prescription of exercise intensity in pulmonary rehabilitation of ILD patients.

High-intensity interval training and pulmonary hemodynamics in COPD with hypoxemia

Background

Exercise is recommended for all patients with COPD. Evidence for its benefit is considerably weaker in the more severe stages of the disease. The aim of this study was to investigate whether high-intensity interval training could improve exercise capacity, pulmonary hemodynamics and cardiac function in patients with severe COPD and hypoxemia.

Methods

Stable patients with COPD GOLD stage III or IV and hypoxemia were included. They underwent extensive cardiopulmonary testing including right heart catheterization, lung function tests, echocardiography and 6-minute walk test before and after completion of 10 weeks of high-intensity interval training performed with supplemental oxygen. Primary endpoint was change in pulmonary artery pressure measured by right heart catheterization.

Results

Ten patients with very severe airflow obstruction, mean FEV1 28.7% predicted and mean FEV1/VC 0.39 completed the exercise programme. Pulmonary artery pressure remained unchanged following the intervention (26,3 mmHg vs. 25,8 mmHg at baseline, p 0.673). Six-minute walk distance improved by a mean of44.8 m (p 0.010), which is also clinically significant. We found marginally improved left ventricular ejection fraction on echocardiography (54.6% vs 59.5%, p 0.046).

Conclusion

High-intensity interval training significantly improved exercise capacity while pulmonary hemodynamics remained unchanged. The improvement may therefore be due to mechanisms other than altered pulmonary artery pressure. The increase in ejection fraction is of uncertain clinical significance. The low number of patients precludes firm conclusions.

Measuring intensity during free-living physical activities in people with chronic obstructive pulmonary disease: a systematic literature review

BACKGROUND

Measuring intensity of physical activity (PA) is important to ensure safety and the effectiveness of PA interventions in chronic obstructive pulmonary disease (COPD).

OBJECTIVE

This systematic review identified which outcomes, outcome measures and instruments have been used to assess single free-living PA-related intensity in people with COPD and compared the intensity level (light, moderate, vigorous) obtained by different outcome measures.

METHODS

PubMed, Scopus, Web of Science, Cochrane Library and EBSCO were searched for original studies of COPD and assessing single free-living PA-related intensity were included. Agreement was calculated as the number of agreements between 2 measures [same intensity level]/ number of comparisons using both measures*100.

RESULTS

We included 43 studies (1282 people with COPD, mean age 66 years, 65% men, 49% FEV_1%pred) and identified 13 outcomes, 46 outcome measures and 22 instruments. The most-reported outcomes, outcome measures and instruments were dyspnoea with the Borg scale 0-10; cardiac function, via heart rate (HR) using HR monitors; and pulmonary gas exchange, namely oxygen consumption (VO₂), using portable gas analysers, respectively. The most frequently assessed PAs were walking and lifting, changing or moving weights/objects. Agreement between the outcome measures ranged from 0 (%VO_2peak vs metabolic equivalent of task [MET]; %HR_peak vs Fatigue Borg; MET vs walking speed) to 100% (%HR_reserve vs dyspnoea Borg; fatigue and exertion Borg vs walking speed). %VO_{2peak/reserve} elicited the highest intensity. Hence, Borg scores, %HR_reserve and MET may underestimate PA-related intensity.

CONCLUSIONS

Various methodologies are used to assess single free-living PA-related intensity and yield different intensity levels for the same PA. Future studies, further exploring the agreement between the different outcome measures of PA-related intensity and discussing their advantages, disadvantages and applicability in real-world settings, are urgent. These would guide future worldwide recommendations on how to assess single free-living PA-related intensity in COPD, which is essential to optimise PA interventions and ensure patient safety.

Effect of counselling during pulmonary rehabilitation on self-determined motivation to be physically active for people with chronic obstructive pulmonary disease: a pragmatic RCT

Background

Counselling is considered to be a promising approach to increasing physical activity (PA) in people with chronic obstructive pulmonary disease (COPD). The aim of the current study was to investigate whether a PA counselling program for people with COPD, when embedded in a comprehensive outpatient pulmonary rehabilitation (PR) program, increased their daily PA.

Methods

A two-armed, single blind randomized controlled trial was conducted as a component of a 12-week outpatient pulmonary rehabilitation program. The participants randomized into the intervention group received five counselling sessions, based on the principles of motivational interviewing (MI), with a physiotherapist. The participants’ steps per day and other proxies of PA were measured using an accelerometer (SenseWear Pro®) at baseline, at the end of the PR program, and three months later. The group-by-time interaction effect was analyzed.

Results

Of the 43 participants,17 were allocated to the intervention group and 26 to the usual-care control group (mean age 67.9 ± 7.9; 21 (49%) males; mean FEV1 predicted 47.1 ± 18.6). No difference between groups was found for any measure of PA at any point in time.

Conclusions

In this study, counselling, based on MI, when embedded in a comprehensive PR program for people with COPD, showed no short-term or long-term effects on PA behavior. To investigate this potentially effective counselling intervention and to analyze the best method, timing and tailoring of an intervention embedded in a comprehensive outpatient PR program, further adequately powered research is needed.

Trial registration: Clinical Trials.gov NCT02455206 (05/21/2015), Swiss National Trails Portal SNCTP000001426 (05/21/2015).

Effects of exercise training in people with non-small cell lung cancer before lung resection: a systematic review and meta-analysis

INTRODUCTION

Exercise training before lung resection for non-small cell lung cancer is believed to decrease postoperative complications (POC) by improving cardiorespiratory fitness. However, this intervention lacks a strong evidence base.

AIM

To assess the effectiveness of preoperative exercise training compared with usual care on POC and other secondary outcomes in patients with scheduled lung resection.

METHODS

A systematic search of randomised trials was conducted by two authors. Meta-analysis was performed, and the effect of exercise training was estimated by risk ratios (RR) and mean differences, with their CIs. Clinical usefulness was estimated according to minimal important difference values (MID).

RESULTS

Fourteen studies involving 791 participants were included. Compared with usual care, exercise training reduced overall POC (10 studies, 617 participants, RR 0.58, 95% CI 0.45 to 0.75) and clinically relevant POC (4 studies, 302 participants, Clavien-Dindo score ≥2 RR 0.42, 95% CI 0.25 to 0.69). The estimate of the effect of exercise training on mortality was very imprecise (6 studies, 456 participants, RR 0.66, 95% CI 0.20 to 2.22). The main risks of bias were a lack of participant blinding and selective reporting. Exercise training appeared to improve exercise capacity, pulmonary function and also quality of life and depression, although the clinical usefulness of the changes was unclear. The quality of the evidence was graded for each outcome.

CONCLUSION

Preoperative exercise training leads to a worthwhile reduction in postoperative complications. These estimates were both accurate and large enough to make recommendations for clinical practice.

Lung volume reduction eligibility in patients with COPD completing pulmonary rehabilitation: results from the UK National Asthma and COPD Audit Programme

OBJECTIVES

To establish what proportion of patients completing a UK pulmonary rehabilitation (PR) programme meet the 2018 National Institute for Health and Care Excellence (NICE) chronic obstructive pulmonary disease (COPD) guideline (NG115) criteria to have a respiratory review to establish whether referral to a lung volume reduction multidisciplinary team would be appropriate. This respiratory review would include evaluation of the presence of hyperinflation and the presence of emphysema on CT scan. The NICE criteria include measures of breathlessness and exercise capacity but these parameters are not completely defined.

DESIGN

Observational study.

SETTING

PR programmes across the UK in 2015 (210 centres) and 2017 (184 centres) entering data into the Royal College of Physicians' National Asthma and COPD Audit Programme.

PARTICIPANTS

8295 (55.7%) of 14 889 patients in programmes using incremental shuttle walk test (ISWT) or 6-minute walk test (6MWT) as an outcome measure completed PR, and 4856 (32.6%) had complete data recorded (6MWT/ISWT, baseline spirometry, Medical Research Council (MRC) dyspnoea score).

RESULTS

Depending on the walking test safety threshold adopted for the ISWT (≥140 m or ≥ 80 m) and the MRC dyspnoea score threshold used (MRC score ≥3 or ≥4 at the end of PR), between 4.9% and 18.1% of PR completers met the NICE criteria for a lung volume reduction-focused respiratory review.

CONCLUSIONS

Lung volume reduction therapies are beneficial in appropriately selected patients with COPD, but few procedures are performed, and treatment pathways are unclear. These data help to inform the feasibility of the approach recommended by NICE and highlight the need for future systematic pathways to reduce inequalities in patients being considered for effective treatments.

Supervised pulmonary rehabilitation using minimal or specialist exercise equipment in COPD: a propensity-matched analysis

BACKGROUND

Many trials supporting the benefits of pulmonary rehabilitation (PR) have used specialist exercise equipment, such as treadmills and cycle ergometers. However, access to specialist equipment may not be feasible in some settings. There is growing interest in delivering PR programmes with minimal, low-cost equipment, but uncertainty remains regarding their efficacy compared with programmes using specialist equipment.

METHODS

Using propensity score matching, 318 consecutive patients with COPD undergoing supervised PR using minimal equipment (PR-min) were compared 1:1 with a control group of 318 patients with COPD who underwent supervised PR using specialist equipment (PR-gym). A non-inferiority analysis was performed for the primary outcome (incremental shuttle walk (ISW)) and secondary outcomes (Chronic Respiratory Disease Questionnaire (CRQ)-domain and total scores).

RESULTS

Similar improvements in ISW and CRQ-domains were observed in PR-min and PR-gym groups (mean difference ISW: 3 m (95% CI -16 to 9); CRQ-total: 0.9 (95% CI -2.7 to 4.5)). The 95% CI between group differences for ISW and CRQ-total did not cross the predefined non-inferiority margins. However, completion rates were lower in PR-min compared with PR-gym (64% vs 73%; p=0.014).

CONCLUSIONS

In patients with COPD, PR delivered using minimal equipment produces clinically significant benefits in exercise capacity and health-related quality of life that are non-inferior to rehabilitation delivered using specialist equipment. This study provides support for the provision of PR using minimal exercise equipment, particularly in areas where access to specialist exercise equipment is limited.