The minimal important difference of exercise tests in severe COPD

Outcomes reported in randomised trials of surgical prehabilitation: a scoping review

BACKGROUND

Heterogeneity of reported outcomes can impact the certainty of evidence for prehabilitation. The objective of this scoping review was to systematically map outcomes and assessment tools used in trials of surgical prehabilitation.

METHODS

MEDLINE, EMBASE, PsychInfo, Web of Science, CINAHL, and Cochrane were searched in February 2023. Randomised controlled trials of unimodal or multimodal prehabilitation interventions (nutrition, exercise, psychological support) lasting at least 7 days in adults undergoing elective surgery were included. Reported outcomes were classified according to the International Society for Pharmacoeconomics and Outcomes Research framework.

RESULTS

We included 76 trials, mostly focused on abdominal or orthopaedic surgeries. A total of 50 different outcomes were identified, measured using 184 outcome assessment tools. Observer-reported outcomes were collected in 86% of trials (n=65), with hospital length of stay being most common. Performance outcomes were reported in 80% of trials (n=61), most commonly as exercise capacity assessed by cardiopulmonary exercise testing. Clinician-reported outcomes were included in 78% (n=59) of trials and most frequently included postoperative complications with Clavien-Dindo classification. Patient-reported outcomes were reported in 76% (n=58) of trials, with health-related quality of life using the 36- or 12-Item Short Form Survey being most prevalent. Biomarker outcomes were reported in 16% of trials (n=12) most commonly using inflammatory markers assessed with C-reactive protein.

CONCLUSIONS

There is substantial heterogeneity in the reporting of outcomes and assessment tools across surgical prehabilitation trials. Identification of meaningful outcomes, and agreement on appropriate assessment tools, could inform the development of a prehabilitation core outcomes set to harmonise outcome reporting and facilitate meta-analyses.

Increasing exercise capacity and physical activity in the COPD patient

Higher levels of exercise capacity and physical activity are desired outcomes in the comprehensive management of the COPD patient. In addition, improvements in exercise capacity and physical activity are instrumental to optimising other important therapeutic goals, such as improved health status, reduced healthcare utilisation and increased survival. Four general approaches towards increasing exercise capacity and physical activity in individuals with COPD will be discussed in this review: 1) pharmacological intervention, especially the administration of long-acting bronchodilators; 2) pulmonary rehabilitation, including exercise training and collaborative self-management; 3) behavioural interventions; and 4) web-based interventions. These are by no means the only approaches, nor are they mutually exclusive: indeed, combining them, as necessary, to meet the needs of the individual respiratory patient may promote optimal outcomes, although further research is necessary in this area.

Optimizing clinical outcomes for bronchoscopic lung volume reduction with Zephyr® valves

Bronchoscopic lung volume reduction treatment with Zephyr one-way valves is an effective guideline-based treatment option for patients with severe emphysema and hyperinflation. However, in some cases the treatment response is less than anticipated or there might be a loss of initial treatment effect. Reasons for the lack of response can include incorrect assessment of collateral ventilation, improper valve placement, or patient related factors. Loss of initial benefit can be due to granulation tissue formation and subsequent valve dysfunction, or there may be side effects such as excessive coughing or infectious problems. Careful follow-up after treatment with valves is important and evaluation with a CT scan and/or bronchoscopy is helpful if there is no improvement after treatment or loss of initial benefit. This paper aims to describe the most important causes and provide a strategy of how to approach and manage these patients.

Review of the Evidence for Pulmonary Rehabilitation in COPD: Clinical Benefits and Cost-Effectiveness

COPD is a common and lethal chronic condition, recognized as a leading cause of death worldwide. COPD is associated with significant morbidity and disability, particularly among older adults. The disease course is marked by periods of stability and disease exacerbations defined by worsening respiratory status resulting in a high burden of health care utilization and an increased risk of mortality. Treatment is focused on pharmacologic therapies, but these are not completely effective. Pulmonary rehabilitation (PR) represents a key medical intervention for patients with chronic respiratory diseases, including COPD. PR provides individualized and progressive exercise training, education, and self-management strategies through a comprehensive and multidisciplinary program. PR has been associated with improvement in exercise capacity, health-related quality of life, and dyspnea in patients living with COPD. Moreover, PR has been associated with improvements in hospital readmission and 1-y survival. In addition to the clinical benefits, PR is estimated to be a cost-effective medical intervention. Despite these benefits, participation in PR remains low. We will review the evidence for PR in each of these benefit domains among patients with stable COPD and in those recovering from a COPD exacerbation.

Responsiveness and minimal clinically important difference of the 6-minute walk distance in patients undergoing colorectal cancer surgery

PURPOSE

This study aimed to clarify the responsiveness and minimal clinically important difference (MCID) of the 6-minute walk distance (6MWD) from before and 1 week after surgery in patients with colorectal cancer (CRC).

METHODS

This retrospective cohort study enrolled 97 patients with primary CRC scheduled for surgery. An anchor-based approach estimated the MCID of the 6MWD, with postoperative physical recovery and EuroQol 5-dimension 5L questionnaire assessments serving as anchors. Effect size (ES) and standardized response mean (SRM) of the 6MWD were calculated to evaluate responsiveness, and the receiver operating characteristic (ROC) curve was used to estimate the MCID of the 6MWD.

RESULTS

Of the 97 patients, 72 were included in the analysis. The absolute value of ES and SRM of the 6MWD were 0.69 and 0.91, respectively. The ROC curve indicated that the optimal cut-off values for estimating the MCID of the 6MWD were -60 m (area under the curve [AUC] = 0.753 [95% CI: 0.640-0.866]) and -75 m (AUC = 0.870 [95% CI: 0.779-0.961]) at each anchor.

CONCLUSION

From before to 1 week after surgery, the responsiveness of the 6MWD was favorable, and the MCID of the 6MWD was -75 to -60 m in patients with CRC.

Validation of Constant Work Rate Cycling Endurance Time for Use in Chronic Obstructive Pulmonary Disease Clinical Trials

Rationale: A COPD Foundation working group sought to identify measures of exercise endurance, a meaningful aspect of physical functioning in everyday life among patients with chronic obstructive pulmonary disease (COPD) that is not fully accepted in regulatory decision making, hampering drug development. Objectives: To demonstrate, as we previously asserted (Casaburi COPD 2022;9:252), that constant work rate cycling endurance time is an appropriate exercise endurance measure in patients with COPD. Methods: To validate this assertion, we assembled an integrated database of endurance time responses, including 8 bronchodilator (2,166 subjects) and 15 exercise training (3,488 subjects) studies (Casaburi COPD 2022;9:520). Results: Construct validity was demonstrated: 1) peak physiologic and perceptual responses were similar for constant work rate and incremental cycling; 2) after bronchodilator therapy, there were greater increases in endurance time in patients with more severe airflow limitation; 3) after exercise training, endurance time increases were similar across airflow limitation severities; and 4) there were correlations between changes in endurance time and changes in mechanistically related physiologic and perceptual variables. Test-retest reliability was demonstrated, with consistency of changes in endurance time at two time points after the intervention. Responsiveness was confirmed, with significant increases in endurance time after active (but not placebo) bronchodilator therapy, with greater increases seen with more severe airflow limitation and after exercise training. On the basis of regression analysis using multiple anchor variables, the minimum important difference for endurance time increase is estimated to be approximately 1 minute. Conclusions: Constant work rate cycling endurance time is a valid exercise endurance measure in COPD, suitable for contributing to the evaluation of treatment benefit supporting regulatory decision making and evidence-based therapeutic recommendations.

Clinical Relevance of Physical Function Outcomes in Cancer Cachexia

Managing clinical manifestations of cancer/treatment burden on functional status and quality of life remains paramount across the cancer trajectory, particularly for patients with cachexia who display reduced functional capacity. However, clinically relevant criteria for classifying functional impairment at a single point in time or for classifying meaningful functional changes subsequent to disease and/or treatment progression are lacking. This unmet clinical need remains a major obstacle to the development of therapies for cancer cachexia. This review aims to describe current literature-based evidence for clinically meaningful criteria for (1) functional impairment at a single timepoint between cancer patients with or without cachexia and (2) changes in physical function over time across interventional studies conducted in patients with cancer cachexia. The most common functional assessment in cross-sectional and interventional studies was hand grip strength (HGS). We observed suggestive evidence that an HGS deficit between 3 and 6 kg in cancer cachexia may display clinical relevance. In interventional studies, we observed that long-duration multimodal therapies with a focus on skeletal muscle may benefit HGS in patients with considerable weight loss. Future studies should derive cohort-specific clinically relevant criteria to confirm these observations in addition to other functional outcomes and investigate appropriate patient-reported anchors.

Preoperative Workup of Patients With Excessive Central Airway Collapse: Does Stent Evaluation Serve a Role?

BACKGROUND

Tracheobronchoplasty (TBP) is a definitive anatomic intervention for patients with severe symptomatic expiratory central airway collapse. Although stent evaluations have been described for surgical workup, current literature does not address if improvement during stent evaluation is sustained after TBP. We compared health-related quality of life (HRQOL) and functional status responses after airway stenting to those post-TBP.

METHODS

A retrospective review was performed in patients with severe expiratory central airway collapse who underwent stent evaluation followed by TBP from January 2004 to December 2019. Baseline, poststent, 3- and 12-month postoperative HRQOL scores, and functional status were analyzed with statistical tests as appropriate.

RESULTS

One hundred twenty patients underwent a stent evaluation and TBP. Baseline and stent evaluation measurements were compared with statistically and clinically significant differences in the Cough Quality-of-life Questionnaire (CQLQ) (55 vs. 68, P <0.01), Modified Medical Research Council (mMRC) 0 to 2 (90% vs. 47%, P <0.01), 6-minute walk test (6MWT) (1301 ft vs. 1138 ft, P <0.01). Improvements in the HRQOL and functional status were maintained from stent evaluation to 3 months postoperatively [CQLQ 55 vs. 54, P =0.63; mMRC 0 to 2 (87% vs. 84%), P =0.39; 6MWT 1350 ft vs. 1314 ft, P =0.33], and 12 months postoperatively [CQLQ 54 vs. 54, P =0.91; mMRC 0 to 2 (95% vs. 86%), P =0.74; 6MWT 1409 ft vs. 1328 ft, P =0.13]. The magnitude of change between the data was not significantly different between the stent evaluation, 3-, and 12 months postoperative. Predicted forced expiratory volume in 1-second measurements at baseline, after stent placement, 3 months, and 12 months post-TBP were 74%, 79%, 73%, and 73%, respectively, and not clinically significant.

CONCLUSIONS

Improvement after stent evaluation and the magnitude of improvement may be predictive of postoperative outcomes up to 1 year after surgery.

Assessing a GPS-Based 6-Minute Walk Test for People With Persistent Pain: Validation Study

BACKGROUND

The 6-minute walk test (6MWT) is a commonly used method to assess the exercise capacity of people with many health conditions, including persistent pain. However, it is conventionally performed with in-person supervision in a hospital or clinic, therefore requiring staff resources. It may also be difficult when in-person supervision is unavailable, such as during the COVID-19 pandemic, or when the person is geographically remote. A potential solution to these issues could be to use GPS to measure walking distance.

OBJECTIVE

The primary aim of this study was to assess the validity of a GPS-based smartphone app to measure walking distance as an alternative to the conventional 6MWT in a population with persistent pain. The secondary aim of this study was to estimate the difference between the pain evoked by the 2 test methods.

METHODS

People with persistent pain (N=36) were recruited to complete a conventional 6MWT on a 30-m shuttle track and a 6MWT assessed by a smartphone app using GPS, performed on outdoor walking circuits. Tests were performed in random order, separated by a 15-minute rest. The 95% limits of agreement were calculated using the Bland-Altman method, with a specified maximum allowable difference of 100 m. Pain was assessed using an 11-point numerical rating scale before and after each walk test.

RESULTS

The mean 6-minute walk distance measured by the GPS-based smartphone app was 13.2 (SD 46; 95% CI -2.7 to 29.1) m higher than that assessed in the conventional manner. The 95% limits of agreement were 103.9 (95% CI 87.4-134.1) m and -77.6 (95% CI -107.7 to -61) m, which exceeded the maximum allowable difference. Pain increased in the conventional walk test by 1.1 (SD 1.0) points, whereas pain increased in the app test by 0.8 (SD 1.4) points.

CONCLUSIONS

In individuals with persistent pain, the 2 methods of assessing the 6MWT may not be interchangeable due to limited validity. Potential reasons for the differences between the 2 methods might be attributed to the variation in track layout (shuttle track vs continuous circuit); poor GPS accuracy; deviations from the 30-m shuttle track; human variability in walking speed; and the potential impact of a first test on the second test due to fatigue, pain provocation, or a learning effect. Future research is needed to improve the accuracy of the GPS-based approach. Despite its limitations, the GPS-based 6MWT may still have value as a tool for remote monitoring that could allow individuals with persistent pain to self-administer frequent assessments of their functional capacity in their home environment.

Effects of 5-Week Oral Acetazolamide on Incremental Cycling Exercise in Pulmonary Arterial and Chronic Thromboembolic Pulmonary Hypertension: A Randomized Placebo-Controlled, Double-Blinded, Crossover Trial

INTRODUCTION

Acetazolamide (AZA) improves nocturnal and daytime blood oxygenation in patients with pulmonary vascular disease (PVD), defined as pulmonary arterial and distal chronic thromboembolic pulmonary hypertension (CTEPH), and may improve exercise performance.

METHODS

We investigated the effect of 5 weeks of AZA (250 mg bid) versus placebo on maximal load during incremental cycling ramp exercise in patients with PVD studied in a randomized controlled, double-blind, crossover design, separated by > 2 weeks of washout.

RESULTS

Twenty-five patients (12 pulmonary arterial hypertension, 13 CTEPH, 40% women, age 62 ± 15 years) completed the trial according to the protocol. Maximum load was similar after 5 weeks of AZA versus placebo (113 ± 9 vs. 117 ± 9 watts [W]), mean difference -4 W (95% CI: -9 to 1, p = 0.138). With AZA, maximum (max)-exercise partial pressure of O2 (PaO2) was significantly higher by 1.1 kPa (95% CI: 0.5-1.8, p = 0.003), while arterial pH and partial pressure of CO2 were significantly lower. Gas exchange threshold was reached at a higher load with AZA (108 ± 8 W vs. 97 ± 8 W) and was therefore delayed by 11 W (95% CI: 3-19, p = 0.013), while the ventilatory equivalent for O2 and CO2 were significantly higher at both the max-exercise and gas exchange threshold with AZA versus placebo.

CONCLUSION

AZA for 5 weeks did not significantly change maximum exercise capacity in patients with PVD despite a significant increase in PaO2. The beneficial effects of increased blood oxygenation may have been diminished by increased ventilation due to AZA-induced metabolic acidosis and increased dyspnea.

Utility of rehabilitation prior to bronchoscopic lung volume reduction: post hoc analysis of the VENT trial

Background and objective

Rehabilitation programmes are a valuable treatment modality for patients with COPD to increase exercise capacity and quality of life. The utility of pulmonary rehabilitation prior to bronchoscopic lung volume reduction (BLVR) is unclear.

Methods

We performed a post hoc analysis of the Valve for Emphysema Palliation Trial (VENT) trial, the first multicentre randomised trial comparing the safety and efficacy of BLVR. Patients completed a pulmonary rehabilitation programme prior to BLVR over 6-10 weeks and maintained by daily practice, consisting of endurance training, strength training and upper/lower limb exercise. Lung function and exercise parameters (6-min walk distance (6MWD)) were assessed before and after rehabilitation and we tried to identify predictors for pulmonary rehabilitation benefit.

Results

Lung function and exercise capacity of 403 patients (mean±sd age 63.3±7.4 years, 37.5% female, mean±sd forced expiratory volume in 1 s 30.1±7.6 L) were analysed. Exercise capacity significantly improved from 331.6±98.8 m to 345.6±95.3 m (p<0.001) in 6-min walk testing (6MWT), with 40.3% showing clinically meaningful improvements. Patients also experienced less dyspnoea after 6MWT, while pulmonary function parameters did not change significantly overall. Patients with lower exercise capacity at screening (6MWD <250 m) benefited more from pulmonary rehabilitation. The indication and prerequisites for BLVR were still present in all patients after pulmonary rehabilitation.

Conclusion

The national mandatory requirements for rehabilitation prior to BLVR, which apply to all COPD patients, should be reconsidered and specified for COPD patients who really benefit.

Transcranial photobiomodulation therapy associated with cardiorespiratory rehabilitation in spastic subjects

The objective of this study was to evaluate the effects of cardiorespiratory rehabilitation (CR) and transcranial photobiomodulation (tPBM) on exercise tolerance (ET), heart rate variability (HRV), and peripheral muscle activity in individuals with spasticity. Fifteen participants with spasticity were randomly assigned to two groups: the tPBM group (tPBMG) consisted of eight volunteers who underwent tPBM (on mode) and CR, while the control group (CG) consisted of seven volunteers who underwent simulated tPBM (off mode) and CR. The CR program included 12 weeks of treatment, twice a week for one hour, involving aerobic exercises and lower limb strengthening. For tPBM, a cluster with three lasers (λ = 680 nm, 808 nm), with a power of 100 mW/laser and energy of 36 J, applied to the F7, F8, and Fpz points. The following parameters were evaluated after 8 and 12 weeks: ET, HRV, and surface electromyography (EMG) of the rectus femoris muscle during orthostasis (ORT), isometric squatting (ISOM), and isotonic squatting (ISOT). Both groups showed a 40% increase in ET for the CG and a 30% increase for the tPBMG. The CG had more pronounced parasympathetic modulation alterations during post-exercise effort and recovery compared to the tPBMG. The EMG results showed that the tPBMG exhibited progressive improvement in muscle activity during ISOM and ISOT, as well as a decrease in the interlimb difference. In conclusion, both CR and tPBMG demonstrated improvements in ET. However, tPBMG specifically showed promising effects on HRV modulation and peripheral muscle electrical activity, providing additional benefits compared to CR alone.

Developing a home-based pulmonary rehabilitation programme for patients with chronic respiratory diseases in Malaysia: A mixed-method feasibility study

Background

The COVID-19 pandemic has underscored the importance of remote healthcare and home-based interventions, including pulmonary rehabilitation, for patients with chronic respiratory diseases (CRDs). It has also heightened the vulnerability of individuals with underlying respiratory conditions to severe illness from COVID-19, necessitating exploration and assessment of the feasibility of delivering home - pulmonary rehabilitation (home-PR) programmes for CRD management in Malaysia and other countries. Home-based programmes offer a safer alternative to in-person rehabilitation during outbreaks like COVID-19 and can serve as a valuable resource for patients who may be hesitant to visit healthcare facilities during such times. We aimed to assess the feasibility of delivering a home-PR programme for patients with CRDs in Malaysia.

Methods

We recruited patients with CRDs from two hospitals in Klang Valley, Malaysia to a home-PR programme. Following centre-based assessment, patients performed the exercises at home (five sessions/week for eight weeks (total 40 sessions)). We monitored the patients via weekly telephone calls and asked about adherence to the programme. We measured functional exercise capacity (6-Minutes Walking Test (6MWT) and Health-Related Quality-of-Life (HRQoL) (COPD Assessment Test (CAT)) at baseline and post-PR at nine weeks. We conducted semi-structured interviews with 12 purposively sampled participants to explore views and feedback on the home-PR programme. The interviews were audio recorded, transcribed verbatim, and analysed thematically.

Results

We included 30 participants; two withdrew due to hospitalisation. Although 28 (93%) adhered to the full programme, only 11 (37%) attended the post-PR assessment because COVID-19 movement restrictions in Malaysia at that time prevented attendance at the centre. Four themes emerged from the qualitative analysis: involvement of family and caregivers, barriers to home-PR programme, interactions with peers and health care professionals, and programme enhancement.

Conclusion

Despite the COVID-19 pandemic, the home-PR programme proved feasible for remote delivery, although centre-based post-PR assessments were not possible. Family involvement played an important role in the home-PR programme. The delivery of this programme can be further improved to maximise the benefit for patients.

Pulmonary telerehabilitation vs. conventional pulmonary rehabilitation - a secondary responder analysis

Home-based pulmonary telerehabilitation (PTR) has been proposed to be equivalent to supervised outpatient pulmonary rehabilitation (PR) but available randomised trials have failed to reach the minimal important changes (MIC). The purpose of this study was to analyse the proportion of MIC responders and non-responders on short-term (10 weeks from baseline) and long-term (62 weeks from baseline) in total and between groups in 134 patients with COPD randomised (1:1) to either home-based PTR or traditional hospital-based outpatient PR. Difference between PTR and PR on 6MWD response proportion could not be shown at 10 (OR=0.72, CI=0.34 to 1.51, p=0.381) or 62 weeks (OR=1.12, CI=0.40 to 3.14, p=0.834). While the evidence and knowledge of PTR accumulate, outpatient supervised PR for now remains the standard of care, with home-based PTR as a strong secondary option for those unable to attend out-patient programmes.

Pulmonary Rehabilitation for Adults with Chronic Respiratory Disease: An Official American Thoracic Society Clinical Practice Guideline

Background: Despite the known benefits of pulmonary rehabilitation (PR) for patients with chronic respiratory disease, this treatment is underused. Evidence-based guidelines should lead to greater knowledge of the proven benefits of PR, highlight the role of PR in evidence-based health care, and in turn foster referrals to and more effective delivery of PR for people with chronic respiratory disease. Methods: The multidisciplinary panel formulated six research questions addressing PR for specific patient groups (chronic obstructive pulmonary disease [COPD], interstitial lung disease, and pulmonary hypertension) and models for PR delivery (telerehabilitation, maintenance PR). Treatment effects were quantified using systematic reviews. The Grading of Recommendations, Assessment, Development and Evaluation approach was used to formulate clinical recommendations. Recommendations: The panel made the following judgments: strong recommendations for PR for adults with stable COPD (moderate-quality evidence) and after hospitalization for COPD exacerbation (moderate-quality evidence), strong recommendation for PR for adults with interstitial lung disease (moderate-quality evidence), conditional recommendation for PR for adults with pulmonary hypertension (low-quality evidence), strong recommendation for offering the choice of center-based PR or telerehabilitation for patients with chronic respiratory disease (moderate-quality evidence), and conditional recommendation for offering either supervised maintenance PR or usual care after initial PR for adults with COPD (low-quality evidence). Conclusions: These guidelines provide the basis for evidence-based delivery of PR for people with chronic respiratory disease.

The minimal important difference of the constant work rate cycle test in severe COPD

BACKGROUND

The Constant Work Rate Cycle Test (CWRT) is a commonly used and sensitive test to detect treatment success in patients with Chronic Obstructive Pulmonary Disease (COPD). Earlier, the Minimal Important Difference (MID) of the CWRT was estimated at 101 s (or 34%) change from baseline based on one well executed study. However, this study was performed in a population of patients with mild-to-moderate COPD, and we have learned that MIDs might be quite different in patients with severe COPD. Therefore, we aimed to establish the MID of the CWRT in patients with severe COPD.

METHODS

We included 141 patients with severe COPD, who underwent either pulmonary rehabilitation, bronchoscopic lung volume reduction with endobronchial valves, or a sham bronchoscopy as a control group. CWRT workload was set at 75% of the peak work capacity, as determined by an incremental cycle test. We used the change in 6-min walking test (6-MWT), forced expiratory volume in 1s (FEV₁), residual volume (RV), and St. George's Respiratory Questionnaire (SGRQ) total score as anchors to calculate the MID.

RESULTS

All anchors had an association of ≥0.41 with change in CWRT. The MID estimates for the different anchors were: 6-MWT 278 s (95%), FEV₁ 273 s (90%), RV 240 s (84%), and SGRQ 208 s (71%). The average of these four MID estimates resulted in an MID of 250 s (or 85%).

CONCLUSION

We established the MID for CWRT at 250 s (or 85%) change from baseline in patients with severe COPD.

Endobronchial Valve Replacements in Patients with Advanced Emphysema After Endoscopic Lung Volume Reduction

Purpose

Up to 41% of patients with endobronchial valve implantation need revision bronchoscopies and valve replacements most likely due to valve dysfunction or lack of benefit. So far, no data is available whether valve replacements lead to the desired lobar volume reduction and therapy benefit.

Patients and Methods

We conducted a single-center retrospective analysis of patients with endobronchial valve implantation and at least one valve replacement. Indications and number of revision bronchoscopies and valve replacements were evaluated. Therapy benefit regarding lung function and exercise capacity as well as development of complete lobar atelectasis was investigated and possible predictors identified.

Results

We identified 73 patients with 1-12 revision bronchoscopies and 1-5 valve replacements. The main indication for revision bronchoscopy in this group was lack of therapy benefit (44.2%). Lung function and exercise capacity showed improvements in about one-third of patients even years after the initial implantation. A total of 26% of all patients showed a complete lobar atelectasis at the end of the observation period, 56.2% had developed lung volume reduction. The logistic regression revealed the development of a previous complete lobar atelectasis as predictor for a complete lobar atelectasis at final follow-up. Oral cortisone long-term therapy was also shown as predictive factor. The probability for a final complete lobar atelectasis was 69.2% if a lobar atelectasis had developed before.

Conclusion

Valve replacements are more likely to be beneficial in patients who develop a re-aeration of a previous lobar atelectasis following valve implantation. Every decision for revision bronchoscopy must be taken carefully.

Efficacy of acupuncture therapy for stable chronic obstructive pulmonary disease: A systematic review and meta-analysis

BACKGROUND

Acupuncture therapy (AT) is a widely used, alternative medicine in China. AT is an effective treatment for many diseases, but its efficacy in stable chronic obstructive pulmonary disease (COPD) remains controversial. Therefore, we performed the present meta-analysis to evaluate the efficacy of AT in stable COPD patients.

METHODS

Randomized controlled trials (RCTs) for AT efficacy in stable COPD patients were searched in literature databases from the inception to December 31, 2021. Pooled effect sizes of outcome measurements with respect to lung function (forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], FEV1 in predicted value [FEV1%], FEV1/FVC), quality of life (St. George respiratory questionnaire [SGRQ]), exercise capacity (6-minute walking distance [6MWD]) and effective rate were estimated by calculating weighted mean difference (WMD) or odds ratio (OR) with corresponding 95% confidence interval (95% CI), respectively, by a random-effect model.

RESULTS

A total of 28 RCTs with 2130 COPD patients were included. AT group had significant improvement in FVC (WMD = 0.29 L, 95% CI: 0.22-0.36, P < .001), FEV1 (WMD = 0.33 L, 95% CI: 0.23-0.43, P < .001), FEV1% (WMD = 3.30%, 95% CI: 3.30-4.64, P < .001), FEV1/FVC (WMD = 5.45%, 95% CI: 4.41-6.49, P < .001), 6MWD (WMD = 45.48 m, 95% CI: 28.21-62.16, P < .001), SGRQ (WMD = -7.79, 95% CI: -12.34 to -3.24, P < .001), and a higher effective rate (OR = 3.71, 95% CI: 2.50-5.52, P < .001) compared to the control group. Subgroup analysis stratified by comparison model (AT combined with other treatments vs other treatments, AT alone vs sham AT) and treatment duration (≥8 weeks, <8 weeks) also showed more improvement in AT arm than control arm without significant between-subgroup difference. Adverse events were reported in a few studies and only mild reactions were observed.

CONCLUSION

AT is effective in improving lung function, quality of life and exercise capacity, and can be used as an adjunctive treatment in patients with stable COPD.

Improved exercise capacity results in a survival benefit after endobronchial valve treatment

BACKGROUND

Bronchoscopic lung volume reduction using endobronchial valves (EBV) is a treatment option for selected patients with advanced emphysema. The treatment significantly improves pulmonary function, exercise capacity, quality of life, and potentially improves survival. Our main aim was to assess whether treatment response significantly influences survival time after EBV treatment.

METHODS

We evaluated treatment response at 6-week and 1-year follow-up of all patients treated with EBVs between 2008 and 2020. Survival status was retrieved on December 1, 2021. Patients were defined as responders or non-responders based on known minimal important differences for FEV₁, residual volume (RV), RV/Total Lung Capacity (TLC) ratio, 6-min walk distance (6MWD), St. George's Respiratory Questionnaire (SGRQ), target lobe volume reduction (TLVR), and complete lobar atelectasis. Uni- and multivariate cox regression models were used to evaluate the effect of response on survival time.

RESULTS

A total of 428 patients were included. EBV treatment resulted in significant improvements in pulmonary function, exercise capacity and quality of life. Median survival was 8.2 years after treatment. SGRQ and 6MWD response were independent predictors for improved survival time (Hazard Ratio (HR) 0.50 [0.28-0.89], p = .02 and HR 0.54 [0.30-0.94], p = .03, respectively). The presence of a complete lobar atelectasis did not significantly affect survival, neither did pulmonary function improvements.

CONCLUSIONS

Our results suggest that improvement in exercise capacity and quality of life after EBV treatment are associated with a survival benefit, independent of improvements in pulmonary function, reduction in target lobe volume or the presence of complete lobar atelectasis.

The minimal clinically important difference in the treadmill six-minute walk test in active women with breast cancer during and after oncological treatments

PURPOSE

To examine the minimal clinically important difference (MCID) in the treadmill 6-minute walk test (6MWT) in women with breast cancer.

MATERIALS AND METHODS

A secondary analysis of cross-sectional data from 112 women who were undergoing chemotherapy or had undergone anticancer treatment was conducted. Participants completed the 6MWT on a treadmill and the European Organization for Research and Treatment of Cancer Questionnaire (EORTC-QLQ-C30) twice, eight weeks apart. Change in the physical function domain of the EORTC-QLQ-C30 was used to classify the "positive change" subgroup (≥5 points difference) and the "unchanged" subgroup (<5 points difference). This was combined with the distance difference from the 6MWTs, determining the MCID as the cut-off from the area under the receiver operating characteristic (AUROC) curve (anchor-based determination). The MCID was also determined from (1) the effect size and (2) the difference in standard error (SEM) of the results of the first and second 6MWT (distribution-based determination).

RESULTS

The MCIDs in the during-chemotherapy group was 66.5 and 41.5 m and those in the after-treatment group to be 41.4 and 40.5 m (SEM and effect size based respectively).

CONCLUSIONS

The MCID in the treadmill 6MWT distance could be used to interpret changes in the physical health status of women with breast cancer.IMPLICATIONS FOR REHABILITATIONThe MCID for the 6MWT on treadmill in active women with breast cancer is of approximately 54 m during chemotherapy, and 41.6 m after treatment.The MCID on treadmill 6MWT distance could be used to interpret a decline in the physical health status of women with breast cancer.The 6MWT on treadmill could be an easy, feasible, performed under controlled conditions, alternative to the 6MWT to obtain valuable information in this population.

Post-Acute COVID-19 Syndrome: 129Xe MRI Ventilation Defects and Respiratory Outcomes One Year Later

Background In people with post-acute COVID-19 syndrome (PACS) and normal pulmonary function, ¹²⁹Xe MRI ventilation defects, abnormal quality-of-life scores, and exercise limitation were reported 3-months after infection; the longitudinal trajectory remains unclear. Purpose To measure and compare pulmonary function, exercise capacity, quality-of-life, and ¹²⁹Xe MRI ventilation defect percent (VDP) in people with PACS evaluated 3- and 15-months post-infection. Materials and Methods In this prospective study, participants with PACS aged 18-80 years were enrolled between July 2020 and August 2021 from two quaternary care centers. They were evaluated 3-months and 15-months post-infection for: ¹²⁹Xe MRI VDP, diffusing capacity of the lung for carbon monoxide (DL_CO), spirometry, oscillometry, six-minute walk distance (6MWD), and St. George's Respiratory Questionnaire (SGRQ). Differences between time-points were evaluated using paired t-tests. Multivariable models were generated to explain exercise capacity and quality-of-life improvements. Odds ratios (OR) were used to evaluate potential treatment influences. Results Fifty-three participants (mean age, 55 years ±18[SD]; 26 male; 27 female) attended both 3- and 15-month visits and were included in analysis. ¹²⁹Xe MRI VDP (5.4%, 4.2%; P=.003), forced expiratory volume in 1-second (85%_pred, 90%_pred; P=.001), DL_CO (89%_pred, 99%_pred; P=.002) and SGRQ (35, 25; P<.001) improved between the 3- and 15-month visit. VDP measured at 3- months post-COVID predicted the change in 6MWD (β=-.643, P=.001) while treatment with respiratory medication at 3-months predicted improved 15-month quality-of-life score (OR=4.0; 95%CI:1.2,13.8, P=.03). Conclusion Pulmonary function, gas-exchange, exercise capacity, quality-of-life, and ¹²⁹Xe MRI ventilation defect percent (VDP) improved in participants with post-acute COVID-19 syndrome evaluated at 15-months as compared to 3-months post-infection. VDP measured at 3-months post-infection correlated with improved exercise capacity, whilst treatment with respiratory medication was associated with improved quality-of-life score at 15-months post-infection. Clinical Trial Registration: www.clinicaltrials.gov NCT05014516 See also the editorial by Vogel-Claussen in this issue.

Bronchoscopic Lung Volume Reduction in Patients with Emphysema due to Alpha-1 Antitrypsin Deficiency

BACKGROUND

Bronchoscopic lung volume reduction using one-way endobronchial valves (EBVs) is a valid therapy for severe emphysema patients. However, alpha-1 antitrypsin (AAT)-deficient patients were excluded from the majority of clinical trials investigating this intervention.

OBJECTIVES

The aim of this study was to investigate the feasibility, efficacy, and safety of EBV treatment in patients with AAT deficiency (AATD) or a reduced AAT level.

METHOD

A retrospective analysis was performed of all patients treated with EBV with confirmed AATD or with a reduced AAT serum level at the University Medical Center Groningen between 2013 and 2021. Baseline and 6-month follow-up assessment included chest CT, pulmonary function measurement, 6-min walking distance (6MWD), and St. George's Respiratory Questionnaire (SGRQ).

RESULTS

In total, 53 patients were included, 30 patients in the AATD group (AAT <0.6 g/L or confirmed ZZ phenotype) and 23 patients in the reduced AAT group (AAT 0.6-1 g/L). In both groups, all response variables improved significantly after treatment. There was a median increase in forced expiratory volume in 1 s of 105 mL (12% relative) and 280 mL (31% relative) in the AATD and reduced AAT groups, respectively. 6MWD increased by 62 min and 52 min, and SGRQ decreased by 12.5 patients and 18.7 patients, respectively. A pneumothorax occurred in 10% and 13% of patients, and no patients died.

CONCLUSIONS

EBV treatment in patients with emphysema and AATD or a reduced AAT level is feasible and results in significant improvements in pulmonary function, exercise capacity, and quality of life and has an acceptable safety profile.

Pulmonary rehabilitation integrated coached exercise training for patients with COPD: a study protocol for a randomized controlled trial

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is the most common chronic lung disease creating an immense burden on social health care systems. Pulmonary rehabilitation (PR) has proven to be effective in patients with COPD. However, exercise training as the basis of PR becomes extremely tedious, occasionally causing a loss of perseverance in patients. Therefore, we considered an approach that makes this technique interesting and easier to persist. The aim of this project was to explore an exercise training approach based on PR-integrated coached exercise training to promote the new exercise training approach as a form of group rehabilitation activity in the future.

METHODS

Participants will be randomly divided into the trial and control groups. The trial group will be treated with PR-integrated coached exercise training (plus usual care). All exercise programs will be guided by sports coaches with a physical education background. Meanwhile, the control group will receive traditional PR and home exercises, including walking and swimming. The study will last for 12 weeks. The primary outcome measure is exercise tolerance using the 6-min walking test and secondary outcomes are the peak oxygen uptake of cardiopulmonary exercise tests, the COPD Assessment Test, and the St. Georges Respiratory Questionnaire. Other evaluated outcomes include changes in postbronchodilator forced expiratory volume at 1^st second, forced vital capacity, body fat and muscle composition, and mental status measured using the Hamilton Anxiety and Depression Scales.

DISCUSSION

This study provides a simple, feasible, repeatable, and fun exercise training approach. To the best of our knowledge, there are no randomized controlled trials in the existing literature on PR-integrated coached exercise. The protocol shared in our study can be used as a reference for exercise training in patients with COPD.

TRIAL REGISTRATION

Ethical approval (BF2020-236-02) was obtained from the Guangdong Provincial Hospital of Chinese Medicine Human Research Ethics Committee. All participants signed an informed consent form. ChiCTR-2100043543. The registration date is 2021/02/21 and it is the third version.

Inspiratory muscle training, with or without concomitant pulmonary rehabilitation, for chronic obstructive pulmonary disease (COPD)

BACKGROUND

Inspiratory muscle training (IMT) aims to improve respiratory muscle strength and endurance. Clinical trials used various training protocols, devices and respiratory measurements to check the effectiveness of this intervention. The current guidelines reported a possible advantage of IMT, particularly in people with respiratory muscle weakness. However, it remains unclear to what extent IMT is clinically beneficial, especially when associated with pulmonary rehabilitation (PR).   OBJECTIVES: To assess the effect of inspiratory muscle training (IMT) on chronic obstructive pulmonary disease (COPD), as a stand-alone intervention and when combined with pulmonary rehabilitation (PR).

SEARCH METHODS

We searched the Cochrane Airways trials register, CENTRAL, MEDLINE, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL) EBSCO, Physiotherapy Evidence Database (PEDro) ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform on 20 October 2021. We also checked reference lists of all primary studies and review articles.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared IMT in combination with PR versus PR alone and IMT versus control/sham. We included different types of IMT irrespective of the mode of delivery. We excluded trials that used resistive devices without controlling the breathing pattern or a training load of less than 30% of maximal inspiratory pressure (PImax), or both.

DATA COLLECTION AND ANALYSIS

We used standard methods recommended by Cochrane including assessment of risk of bias with RoB 2. Our primary outcomes were dyspnea, functional exercise capacity and health-related quality of life.  MAIN RESULTS: We included 55 RCTs in this review. Both IMT and PR protocols varied significantly across the trials, especially in training duration, loads, devices, number/ frequency of sessions and the PR programs. Only eight trials were at low risk of bias. PR+IMT versus PR We included 22 trials (1446 participants) in this comparison. Based on a minimal clinically important difference (MCID) of -1 unit, we did not find an improvement in dyspnea assessed with the Borg scale at submaximal exercise capacity (mean difference (MD) 0.19, 95% confidence interval (CI) -0.42 to 0.79; 2 RCTs, 202 participants; moderate-certainty evidence).   We also found no improvement in dyspnea assessed with themodified Medical Research Council dyspnea scale (mMRC) according to an MCID between -0.5 and -1 unit (MD -0.12, 95% CI -0.39 to 0.14; 2 RCTs, 204 participants; very low-certainty evidence).  Pooling evidence for the 6-minute walk distance (6MWD) showed an increase of 5.95 meters (95% CI -5.73 to 17.63; 12 RCTs, 1199 participants; very low-certainty evidence) and failed to reach the MCID of 26 meters. In subgroup analysis, we divided the RCTs according to the training duration and mean baseline PImax. The test for subgroup differences was not significant. Trials at low risk of bias (n = 3) demonstrated a larger effect estimate than the overall. The summary effect of the St George's Respiratory Questionnaire (SGRQ) revealed an overall total score below the MCID of 4 units (MD 0.13, 95% CI -0.93 to 1.20; 7 RCTs, 908 participants; low-certainty evidence).  The summary effect of COPD Assessment Test (CAT) did not show an improvement in the HRQoL (MD 0.13, 95% CI -0.80 to 1.06; 2 RCTs, 657 participants; very low-certainty evidence), according to an MCID of -1.6 units.  Pooling the RCTs that reported PImax showed an increase of 11.46 cmH₂O (95% CI 7.42 to 15.50; 17 RCTs, 1329 participants; moderate-certainty evidence) but failed to reach the MCID of 17.2 cmH₂O.  In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness.  One abstract reported some adverse effects that were considered "minor and self-limited". IMT versus control/sham Thirty-seven RCTs with 1021 participants contributed to our second comparison. There was a trend towards an improvement when Borg was calculated at submaximal exercise capacity (MD -0.94, 95% CI -1.36 to -0.51; 6 RCTs, 144 participants; very low-certainty evidence). Only one trial was at a low risk of bias. Eight studies (nine arms) used the Baseline Dyspnea Index - Transition Dyspnea Index (BDI-TDI). Based on an MCID of +1 unit, they showed an improvement only with the 'total score' of the TDI (MD 2.98, 95% CI 2.07 to 3.89; 8 RCTs, 238 participants; very low-certainty evidence). We did not find a difference between studies classified as with and without respiratory muscle weakness. Only one trial was at low risk of bias. Four studies reported the mMRC, revealing a possible improvement in dyspnea in the IMT group (MD -0.59, 95% CI -0.76 to -0.43; 4 RCTs, 150 participants; low-certainty evidence). Two trials were at low risk of bias. Compared to control/sham, the MD in the 6MWD following IMT was 35.71 (95% CI 25.68 to 45.74; 16 RCTs, 501 participants; moderate-certainty evidence). Two studies were at low risk of bias. In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness.  Six studies reported theSGRQ total score, showing a larger effect in the IMT group (MD -3.85, 95% CI -8.18 to 0.48; 6 RCTs, 182 participants; very low-certainty evidence). The lower limit of the 95% CI exceeded the MCID of -4 units. Only one study was at low risk of bias. There was an improvement in life quality with CAT (MD -2.97, 95% CI -3.85 to -2.10; 2 RCTs, 86 participants; moderate-certainty evidence). One trial was at low risk of bias. Thirty-two RCTs reported PImax, showing an improvement without reaching the MCID (MD 14.57 cmH₂O, 95% CI 9.85 to 19.29; 32 RCTs, 916 participants; low-certainty evidence). In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness.   None of the included RCTs reported adverse events.

AUTHORS' CONCLUSIONS

IMT may not improve dyspnea, functional exercise capacity and life quality when associated with PR. However, IMT is likely to improve these outcomes when provided alone. For both interventions, a larger effect in participants with respiratory muscle weakness and with longer training durations is still to be confirmed.

Pulmonary Function Trajectories in People with HIV: Analysis of the Pittsburgh HIV Lung Cohort

Rationale: Human immunodeficiency virus (HIV) infection is associated with chronic lung disease and impaired pulmonary function; however, longitudinal pulmonary function phenotypes in HIV are undefined. Objectives: To identify pulmonary function trajectories, their determinants, and outcomes. Methods: We used data from participants with HIV in the Pittsburgh HIV Lung Cohort with three or more pulmonary function tests between 2007 and 2020. We analyzed post-bronchodilator forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC, and diffusing capacity of the lung for carbon monoxide (DlCO) using group-based trajectory modeling to identify subgroups of individuals whose measurements followed a similar pattern over time. We examined the association between participant characteristics and trajectories using multivariable logistic regression. In exploratory adjusted analyses restricted to individuals with available plasma cytokine data, we investigated the association between 18 individual standardized cytokine concentrations and trajectories. We compared mortality, dyspnea prevalence, respiratory health status, and 6-minute-walk distance between phenotypes. Results: A total of 265 participants contributed 1,606 pulmonary function measurements over a median follow-up of 8.1 years. We identified two trajectories each for FEV1 and FVC: "low baseline, slow decline" and "high baseline, rapid decline." There were three trajectory groups for FEV1/FVC: "rapid decline," "moderate decline," and "slow decline." Finally, we identified two trajectories for DlCO: "baseline low" and "baseline high." The low baseline, slow decline FEV1 and FVC, rapid decline, and moderate decline FEV1/FVC, and baseline low DlCO phenotypes were associated with increased dyspnea prevalence, worse respiratory health status, and decreased 6-minute-walk distance. The baseline low DlCO phenotype was also associated with worse mortality. Current smoking and pack-years of smoking were associated with the adverse FEV1, FEV1/FVC, and DlCO phenotypes. Detectable viremia was the only HIV marker associated with the adverse DlCO phenotype. C-reactive protein and endothelin-1 were associated with the adverse FEV1 and FVC phenotypes, and endothelin-1 trended toward an association with the adverse DlCO phenotype. Conclusions: We identified novel, distinct longitudinal pulmonary function phenotypes with significant differences in characteristics and outcomes. These findings highlight the importance of lung dysfunction over time in people with HIV and should be validated in additional cohorts.

Comparing cardiac function and structure and their relationship with exercise capacity between patients with stable COPD and recent acute exacerbation: a cross-sectional study

OBJECTIVE

Patients with COPD are prone to cardiac remodeling; however, little is known about cardiac function in patients recovering from an acute exacerbation of COPD (AECOPD) and its association with exercise capacity. The aim of this study was to evaluate the cardiac function and structure and to compare their relationship with exercise capacity in patients with a recent AECOPD and patients with clinically stable COPD.

METHODS

This was a cross-sectional study including 40 COPD patients equally divided into two groups: recent AECOPD group (AEG) and clinically stable COPD group (STG). Echocardiography was performed to assess cardiac function and chamber structure. The six-minute walk distance (6MWD) and the Duke Activity Status Index (estimated Vo2) were used in order to assess exercise capacity.

RESULTS

No significant differences in cardiac function and structure were found between the groups. The 6MWD was associated with early/late diastolic mitral filling velocity ratio (r = 0.50; p < 0.01), left ventricular posterior wall thickness (r = -0.33; p = 0.03), and right atrium volume index (r = -0.34; p = 0.04), whereas Vo2 was associated with right atrium volume index (r = -0.40; p = 0.02).

CONCLUSIONS

Regardless of the clinical condition (recent AECOPD vs. stable COPD), the cardiac function and structure were similar between the groups, and exercise capacity (determined by the 6MWD and Vo2) was associated with cardiac features.

Performance Score (T2D)-A New Perspective in the Assessment of Six-Minute Walking Tests in Pulmonary Rehabilitation

Because absolute changes in outcomes are difficult to interpret and the minimal clinically important difference (MCID) is not suitable to address this challenge, a novel method of classifying outcomes by relating changes to baseline values is warranted. We used the "performance score" (T2D), which reflects individual performance, enabling us to consider the functional status at the beginning of rehabilitation without dealing with the problems of mathematical coupling or regression effects, as encountered in ANCOVA. To illustrate the T2D, we retrospectively analyzed changes in the six-minute walking test (6MWT) in COPD patients undergoing outpatient pulmonary rehabilitation and compared the results with absolute differences related to a predetermined MCID. We evaluated a total of 575 COPD patients with a mean age of 61.4 ± 9.2 years. 6MWT improved significantly, with a mean change of 32.3 ± 71.2. A total of 105/311 participants who had reached the MCID were still classified as "below average" by the T2D. Conversely, 76/264 patients who had not reached the MCID were classified as "above average". This new performance measure accounts for the patient's current status and for changes over time, potentially representing a simple and user-friendly tool that can be used to quantify a patient's performance and response to rehabilitation.

Can Iron Play a Crucial Role in Maintaining Cardiovascular Health in the 21st Century?

In the 21st century the heart is facing more and more challenges so it should be brave and iron to meet these challenges. We are living in the era of the COVID-19 pandemic, population aging, prevalent obesity, diabetes and autoimmune diseases, environmental pollution, mass migrations and new potential pandemic threats. In our article we showed sophisticated and complex regulations of iron metabolism. We discussed the impact of iron metabolism on heart diseases, treatment of heart failure, diabetes and obesity. We faced the problems of constant stress, climate change, environmental pollution, migrations and epidemics and showed that iron is really essential for heart metabolism in the 21st century.

Mapping the global research landscape and hotspot of exercise therapy and chronic obstructive pulmonary disease: A bibliometric study based on the web of science database from 2011 to 2020

Background: The application of exercise therapy (ET) in chronic obstructive pulmonary disease (COPD) is generating increasing clinical efficacy and social-economic value. In this study, research trends, evolutionary processes and hot topics in this field are detailed, as well as predictions of future development directions.

Methods: Search for literature in the field of COPD and ET and analyze data to generate knowledge graphs using VOSiewer and CiteSpace software. The time frame for the search was from 2011 to January 2021. Then we extracted full-text key information (such as title, journal category, publication date, author, country and institution, abstract, and keyword) and obtained the co-citation analysis. Use hierarchal clustering analysis software developed by VOSviewer to map common citations, and use Citespace software to plot trend networks.

Results: The United States topped the list with 27.91% of the number of articles posted, followed by the UK at 25.44%. Imperial College London was the highest number of article publications in institutions, followed by Maastricht University and the University of Toronto. The Royal Brompton Harefield NHS Foundation Trust was one of many research institutions and currently holds the highest average citations per item (ACI) value, followed by Imperial College London and the University of Leuven. Judging from the number of publications related to ET and COPD, it is mainly published in cell biology, respiratory pulmonary diseases, and rehabilitation experiments study medicine. The European Respiration Journal is the most widely published in this field, followed by the International Journal of Chronic Obstructive Pulmonary Disease and Respiratory Medicine.

Conclusion: COPD combined with ET is widely used in clinical practice and is on the rise. A distinctive feature of the field is multidisciplinary integration. Rehabilitation research for COPD involves multidisciplinary collaboration, tissue engineering, and molecular biology mechanism studies to help patients remodel healthy breathing. Multidisciplinary rehabilitation measures provide a solid foundation for advancing clinical efficacy in the field of COPD.

Minimal important difference of two methods for assessment of quadriceps femoris strength post exercise program in individuals with COPD

BACKGROUND

The assessment of quadriceps femoris (QF) strength is recommended by international guidelines as an outcome of exercise training (ET) programs in patients with chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To identify the minimal important difference (MID) of two methods for the assessment of improvement of QF strength after a high-intensity ET program in individuals with COPD: 1-repetition maximum (1RM) and maximal voluntary contraction (MVC).

METHODS

Individuals with moderate to very-severe stable COPD were submitted to high-intensity ET (3 days/week, 36 sessions). Lung function (spirometry), exercise capacity (6-minute walk test [6MWT]) and QF strength (1RM test and MVC by using a strain-gauge) were assessed before and after the ET program.

RESULTS

Twenty-one individuals were studied (65±8 years, BMI 27±6; FEV₁ 51±16%predicted). At the end of the ET program, QF strength improved significantly (10±4 Nm for MVC and 8 ± 6 kg for 1RM) (P<0.05 for both). The MID for improvement of the QF strength calculated by distribution-based methods ranged from 9.4 to 16 Nm (between 7.4% and 12.6% increase from baseline) for the MVC and from 2.5 to 3 kg (between 12% and 15% increase from baseline) for the 1RM test. Anchor-based MIDs could not be calculated since there was no correlation between the improvement of QF strength and the improvement of the proposed anchor (6MWT).

CONCLUSIONS

The MID for improvement of QF strength after a high-intensity ET program in individuals with moderate-to-severe stable COPD ranges between 9.4 and 16 Nm for the MVC assessed with a strain gauge and between 2.5 and 3 kg for the 1RM test.

Potential Explanatory Factors for the Concurrent Experience of Dyspnea and Pain in Patients with COPD

Previous research has identified unexpectedly strong associations between dyspnea and pain, but the reasons remain unclear. Ascertaining the underlying biological and psychological mechanisms might enhance the understanding of the experience of both conditions, and suggest novel treatments. We sought to elucidate whether demographic factors, disease severity, psychological symptoms and biomarkers might account for the association between pain and dyspnea in individuals with COPD. We analyzed data from 301 patients with COPD who were followed in a prospective longitudinal observational study over 2 years. Measures included self-reported dyspnea and pain, pulmonary function tests, serum levels of inflammatory cytokines, measures of physical deconditioning, and scales for depression and anxiety. Analyses involved cross-sectional and longitudinal linear regression models. Pain and dyspnea were strongly correlated cross-sectionally (r = 0.77, 95% CI 0.72-0.82) and simultaneously across time (r = 0.42, 95% CI 0.28-0.56). Accounting for any of the other health factors only slightly mitigated the associations. Symptoms of pain and dyspnea thus may be fundamentally linked in COPD, rather than being mediated by common biological, psychological, or functional factors. From the patient's perspective, pain and dyspnea may be part of the same essential experience. It is possible that treatments for one condition would improve the other.

Clinical outcomes and quantitative CT analysis after bronchoscopic lung volume reduction using valves for advanced emphysema

Background

Bronchoscopic lung volume reduction (BLVR) using Zephyr endobronchial valve (EBV) and intrabronchial valve (IBV) has been shown to improve lung function and exercise capacity in severe emphysema. However, changes in airway structures and whether these are related to the clinical improvements remain unclear.

Methods

A retrospective study was performed on patients treated with BLVR. We compared changes in 2nd-, 3rd-, and 4th-generation bronchial structures after therapy, including wall thickness (WT), percentage of wall thickness (WT%), intraluminal area (LA), wall area (WA), and WA%. Responder and non-responder subgroup analysis according to minimum clinically important difference (MCID) which was defined as an improvement of 15% in forced expiratory volume in 1 s (FEV₁) and 26 m in 6 min walk distance (6MWD) was conducted.

Results

Of the 19 patients, 11 were treated with EBV and 8 with IBV. In ipsilateral non-target lobes, WT% decreased significantly in 3rd-generation bronchi at 1 month, 3, and 6 months, as well as their WA% at 1 month and 6 months. Non-responders, who were unable to achieve MCID, showed no consistent bronchial wall changes. And their LA of 3rd-generation bronchi decreased especially at 1 month. After BLVR, the target lobe volume decreased significantly until 12 months of follow-up. The volume of ipsilateral lobes could increase correspondingly and achieve the best improvements at 6 months. The contralateral lung volume showed slight amelioration but there was no statistical significance.

Conclusions

Both airway structures and lung volumes showed changes after BLVR. The 3rd- and 4th-bronchial walls tend to be thinner, which were consistent with clinical improvements. Further studies are needed to prove this conclusion and find detect potential mechanics.

Chronic Alcohol Dysregulates Glutamatergic Function in the Basolateral Amygdala in a Projection-and Sex-Specific Manner

Chronic intermittent ethanol and withdrawal (CIE/WD) produces alcohol dependence, facilitates anxiety-like behavior, and increases post-CIE alcohol intake. The basolateral amygdala (BLA) is one of several brain regions that regulates anxiety-like behavior and alcohol intake through downstream projections to the nucleus accumbens (NAC) and bed nucleus of the stria terminalis (BNST), respectively. Previous studies revealed that CIE/WD induces input- and sex-specific adaptations to glutamatergic function in the BLA. The BLA receives information from two distinct input pathways. Glutamatergic afferents from medial structures like the thalamus and prefrontal cortex enter the BLA through the stria terminalis whereas lateral cortical structures like the anterior insula cortex enter the BLA through the external capsule. CIE/WD increases presynaptic glutamatergic function at stria terminalis synapses and postsynaptic function at external capsule synapses. Previous studies sampled neurons throughout the BLA, but did not distinguish between projection-specific populations. The current study investigated BLA neurons that project to the NAC (BLA-NAC neurons) or the BNST (BLA-BNST neurons) as representative “reward” and “aversion” BLA neurons, and showed that CIE/WD alters glutamatergic function and excitability in a projection- and sex-specific manner. CIE/WD increases glutamate release from stria terminalis inputs only onto BLA-BNST neurons. At external capsule synapses, CIE/WD increases postsynaptic glutamatergic function in male BLA-NAC neurons and female BLA-BNST neurons. Subsequent experiments demonstrated that CIE/WD enhanced the excitability of male BLA-NAC neurons and BLA-BNST neurons in both sexes when glutamatergic but not GABAergic function was intact. Thus, CIE/WD-mediated increased glutamatergic function facilitates hyperexcitability in male BLA-NAC neurons and BLA-BNST neurons of both sexes.

Comparative Impact of Depressive Symptoms and FEV1% on Chronic Obstructive Pulmonary Disease

Rationale: Individuals with chronic obstructive pulmonary disease (COPD) have a high prevalence of depression, which is associated with increased COPD hospitalizations and readmissions. Objectives: Examine the impact of depressive symptoms compared with FEV₁% on COPD morbidity. Methods: Using longitudinal data from individuals with COPD in the Subpopulations and Intermediate Outcome Measures in COPD Study, longitudinal growth analysis was performed to assess COPD morbidity by assessing differences in baseline 6-minute walk distance and patient reported outcomes (PROs) and their rate of change over time explained by depressive symptoms or lung function, as measured by Hospital Anxiety and Depression Scale or FEV₁% respectively. PROs consisted of in-person completion of St. George's Respiratory Questionnaire, COPD Assessment Test, Functional Assessment of Chronic Illness Therapy Fatigue, and Modified Medical Research Council Dyspnea Scale measures. Results: Of the individuals analyzed (n = 1,830), 43% were female, 81% Caucasian with mean ± SD age of 65.1 ± 8.1, and 52.7 ± 27.5 pack-years smoking. Mean ± SD FEV₁% was 60.9 ± 23.0% and 20% had clinically significant depressive symptoms. Adjusted models showed higher Hospital Anxiety and Depression Scale scores and lower FEV₁% each were associated with worse PROs at baseline (P ⩽ 0.001). Depression accounted for more baseline variance in St. George's Respiratory Questionnaire, COPD Assessment Test, and Functional Assessment of Chronic Illness Therapy Fatigue than FEV₁%, explaining 30-67% of heterogeneity. FEV₁% accounted for more baseline variance in Modified Medical Research Council Dyspnea Scale and 6-minute walk distance than depression, explaining 16-32% of heterogeneity. Depressive symptoms accounted for 3-17% variance in change over time in PROs. In contrast, FEV₁% accounted for 1-4% variance over time in PROs. Conclusions: Depression is more strongly associated with many PROs at baseline and their change over time compared with FEV₁%. Recognizing and incorporating the impact of depressive symptoms into individualized care may improve COPD outcomes.

The effect of Kappaphycus alvarezii active fraction on oxidative stress and inflammation in streptozotocin and nicotinamide-induced diabetic rats

BACKGROUND

High glucose concentration increases the glycation process which leads to oxidative stress and inflammation, that can cause complications in diabetes. Several medicinal plants have been used in the treatment of diabetes and its complications. One of them is Kappaphycus alvarezii, an algae that has known antidiabetic abilities. This study aimed to examine the effect of K. alvarezii active fraction on plasma hydrogen peroxide (H2O2) and Tumor Necrosis Factor α (TNFα) levels, renal NADPH oxidase 4 (NOX4) and Nuclear Factor κ B (NFκB) gene expressions.

METHODS

Active fraction was obtained from bioassay-guided fractionation with antiglycation ability. In vivo study was performed on twenty Wistar male rats. The level of H2O2 was measured using H2O2 Assay Kit, the Optical Density value measured using spectrophotometer at a wavelength of 405 nm. Plasma TNFα level was measured using ELISA. Renal NOX4 and NFκB gene expression was analyzed using qPCR.

RESULTS

Active fraction significantly reduced plasma H2O2 but not TNFα levels. Furthermore, renal NOX4 gene expression was lower in the diabetic rat group treated with active fraction compared to the untreated group but not NFκB gene expression.

CONCLUSIONS

K. alvarezii active fraction has an activity to reduce plasma H2O2 as well as renal NOX4 gene expression. Therefore, this fraction could be developed as a potential candidate for diabetes treatment through oxidative stress mechanisms.

Playing the harmonica with chronic obstructive pulmonary disease. A qualitative study

Objectives: To investigate the experience of playing the harmonica for individuals with COPD.

Methods: A qualitative, phenomenological study using semi-structured interviews and reflexive thematic analysis.

Results: Eight people living with COPD (six females, two males) were recruited, who had attended at least six weeks of harmonica group sessions, either face-to-face prior to the COVID-19 pandemic or remotely. Five themes were generated. Themes included ‘hard in the beginning’, ‘holding the condition’, ‘breathing control’, ‘gives you a high’ and ‘needing the Zoom class’.

Discussion: Playing the harmonica with COPD is difficult at first, particularly drawing a breath through the harmonica. With practice, experience in a fun activity and quality teaching, individuals were able to become more attuned and embodied with their breathing, and playing the harmonica offered a breathing control strategy. Songs, rather than breathing, became the focus, and participants were able to escape living with respiratory disease when playing. Participants reported the harmonica helped mucous expectoration. The group was a priority in the weekly lives of participants, even though the ‘buzz’ of being part of a group was lost when participating online. Further mechanistic studies and randomised controlled trials are needed to investigate the biopsychosocial benefits of playing the harmonica with COPD.

Effect of oxygen therapy on exercise performance in patients with cyanotic congenital heart disease: Randomized-controlled trial

BACKGROUND

Patients with unrepaired cyanotic congenital heart disease (CHD) suffer from aggravated hypoxemia during exercise. We tested the hypothesis that supplemental oxygen improves exercise performance in these patients.

METHODS

In this randomized, sham-controlled, single-blind, cross-over trial cyanotic CHD-patients underwent four cycle exercise tests to exhaustion, while breathing either oxygen-enriched (FiO₂ 0.50, oxygen) or ambient air (FiO₂ 0.21, air) using incremental (IET) or constant work-rate (CWRET) exercise test protocols (75% of maximal work rate achieved under FiO₂ 0.21). Pulmonary gas-exchange, electrocardiogram, arterial blood gases, oxygen saturation (SpO₂), cerebral and quadriceps muscle tissue oxygenation (CTO and QMTO) by near-infrared spectroscopy were measured.

RESULTS

We included seven patients with cyanotic CHD (4 Eisenmenger syndrome, 3 unrepaired cyanotic defects, 4 women) median (quartiles) age 36 (32;50) years, BMI 23 (20;26) kg/m² and SpO₂ at rest 87 (83;89) %. When comparing supplemental oxygen with air during exercise, maximal work-rate in IET increased from 76 (58;114) Watts to 83 (67;136) Watts, median difference 9 (0;22) W (p = 0.046) and CWRET-time increased from 412 s (325;490) to 468 s (415;553), median increase 56 (39;126) s (p = 0.018). In both IET and CWRET SpO₂ was significantly higher and ventilatory equivalent for carbon dioxide significantly lower at end-exercise with oxygen compared to air, whereas CTO and QMTO did not significantly differ.

CONCLUSIONS

Patients with cyanotic CHD significantly improved their exercise performance, in terms of maximal work-rate and endurance time along with an improved arterial oxygenation and ventilatory efficiency with supplemental oxygen compared to air.

The role of personality traits in inpatient pulmonary rehabilitation response in patients with chronic obstructive pulmonary disease

BACKGROUND

The effectiveness of pulmonary rehabilitation (PR) is a critical issue for chronic obstructive pulmonary disease (COPD) patients. However, PR response is marked by a strong heterogeneity, partially unexplained to date. We hypothesized that personality traits defined by the Five-Factor Model could modulate the effect of inpatient-PR.

OBJECTIVE

The aim was to assess the associations between these five personality traits and PR outcomes.

METHODS

74 persons with COPD admitted for a 5-week inpatient PR program had a personality assessment at the start of the program (T1). Exercise capacity, quality of life, sensory and affective dyspnea dimensions were assessed at T1 and at the end of the program (T2). Their evolution was evaluated using the delta score between T2 and T1. PR response was defined using the minimal clinically important change score for each of them. A composite response was established distinguishing the poor responders' group, made of patients who responded to 0, 1 or 2 parameters and the good responders' group, with patients who responded on 3 or 4 indicators.

RESULTS

Logistic regressions analyses highlighted that those with a high level of openness [OR = 0.36, 95% CI = 0.15-0.74, p < 0.01] were less likely to respond on quality of life, controlling for socio-demographic factors and the severity of the disease.

CONCLUSION

This study shows that the investigation of the personality constitutes an interesting perspective for better understanding the interindividual differences observed between patients in the PR response. Tailoring clinical intervention to the patient's personality could be a promising prospect for optimizing PR effectiveness.

Factors influencing participation in educational workshops as part of a pulmonary rehabilitation program in patients with chronic obstructive pulmonary disease: a retrospective study

BACKGROUND

Pulmonary rehabilitation (PR) (primarily composed of an exercise training program (ET) and educational workshops) is an effective intervention for patients with chronic obstructive pulmonary disease. Although factors which influence participation in the full PR program have been reported, specific data on the educational component of PR have not been published. We aimed to identify factors which predict refusal to participate in the educational component of PR.

RESEARCH DESIGN AND METHODS

201 patient charts were retrospectively included in the analysis. Patients were classified according to their acceptance or refusal to participate in the educational workshops.

RESULTS

The location of ET outside the center was independently related to refusal to participate in the educational workshops (OR = 0.01 [95%CI 0.00 to 0.17]). Patients who refused the workshops were less disabled according to the number of prescriptions of noninvasive ventilation, use of medical transport, oxygen consumption and workload achieved during cardiopulmonary exercise testing.

CONCLUSIONS

The location of exercise sessions during PR influences patients' decisions to refuse or accept center-based educational workshops. When center-based PR programs are limited, and the ET is relocated to the patient's home, the educational workshops should also be relocated.

TRIAL REGISTRATION

The trial is registered at ClinicalTrials.gov (NCT04301245).

Minimal clinically important difference in postoperative recovery among patients with gastrointestinal cancer

PURPOSE

The minimal clinically important difference (MCID) based on patient-reported outcomes is the smallest outcome change sufficiently significant to influence management and is crucial to the design and interpretation of comparative effectiveness trials. The purpose of this study was to estimate the MCID for postoperative recovery metrics in gastrointestinal cancer patients.

METHODS

This was a three-institutional cohort study. Participants were 219 patients scheduled for gastrointestinal cancer elective surgery. Body mass index (BMI), isometric knee extension torque (IKET), 6-min walk test (6 MWT), and Short-Form 36-Item Health Survey (SF-36) version 2 were evaluated 1-2 days prior to surgery (baseline) and 4 weeks after surgery. Patients received postoperative rehabilitative care from a physical therapist during hospitalization. The MCID used anchor-based methods. The anchor was a score on the SF-36 physical functioning subscale greater or lower than the average score of the general Japanese population.

RESULTS

The receiver operating curve indicated a cutoff value on the 6 MWT of -7.8 m for clinically relevant decline (area under curve [AUC] = 0.67, 95% confidence interval [CI] = 0.599-0.741) or a 1.5% change. The cutoff value on the SF-36 role-physical subscale was -34.4 for clinically relevant decline (AUC = 0.691, 95% CI = 0.621-0.761) or a 36.6% decrease. No significant correlation was found between changes in BMI, IKET, and anchor.

CONCLUSION

Plausible MCIDs are present in patients with gastrointestinal cancer. These values can assist the interpretation of clinical trials and observation of the postoperative clinical course of gastrointestinal cancer surgery.

Effect of Automated Oxygen Titration during Walking on Dyspnea and Endurance in Chronic Hypoxemic Patients with COPD: A Randomized Crossover Trial

The need for oxygen increases with activity in patients with COPD and on long-term oxygen treatment (LTOT), leading to periods of hypoxemia, which may influence the patient’s performance. This study aimed to evaluate the effect of automated oxygen titration compared to usual fixed-dose oxygen treatment during walking on dyspnea and endurance in patients with COPD and on LTOT. In a double-blinded randomised crossover trial, 33 patients were assigned to use either automated oxygen titration or the usual fixed-dose in a random order in two walking tests. A closed-loop device, O2matic delivered a variable oxygen dose set with a target saturation of 90–94%. The patients had a home oxygen flow of (mean ± SD) 1.6 ± 0.9 L/min. At the last corresponding isotime in the endurance shuttle walk test, the patients reported dyspnea equal to median (IQR) 4 (3–6) when using automated oxygen titration and 8 (5–9) when using fixed doses, p < 0.001. The patients walked 10.9 (6.5–14.9) min with automated oxygen compared to 5.5 (3.3–7.9) min with fixed-dose, p < 0.001. Walking with automated oxygen titration had a statistically significant and clinically important effect on dyspnea. Furthermore, the patients walked for a 98% longer time when hypoxemia was reduced with a more well-matched, personalised oxygen treatment.

Effectiveness of a Three-Week Inpatient Pulmonary Rehabilitation Program for Patients after COVID-19: A Prospective Observational Study

For COVID-19 patients who remain symptomatic after the acute phase, pulmonary rehabilitation (PR) is recommended. However, only a few studies have investigated the effectiveness of PR, especially considering the duration between the acute phase of COVID-19 and the onset of rehabilitation, as well as the initial severity. This prospective observational study evaluated the efficacy of PR in patients after COVID-19. A total of 120 still-symptomatic patients referred for PR after overcoming acute COVID-19 were asked to participate, of whom 108 (mean age 55.6 ± 10.1 years, 45.4% female) consented. The patients were assigned to three groups according to the time of referral and initial disease severity (severe acute; severe after interval; mild after interval). The primary outcome was dyspnea. Secondary outcomes included other respiratory disease symptoms, physical capacity, lung function, fatigue, quality of life (QoL), depression, and anxiety. Furthermore, patients rated the overall effectiveness of PR and their subjective change in health status. At the end of PR, we detected improvements with large effect sizes in exertional dyspnea, physical capacity, QoL, fatigue, and depression in the overall group. Other parameters changed with small to medium effect sizes. PR was effective after acute COVID-19 in all three groups analyzed.

Chronic non-invasive ventilation for chronic obstructive pulmonary disease

BACKGROUND

Chronic non-invasive ventilation (NIV) is increasingly being used to treat people with COPD who have respiratory failure, but the evidence supporting this treatment has been conflicting.

OBJECTIVES

To assess the effects of chronic non-invasive ventilation at home via a facial mask in people with COPD, using a pooled analysis of IPD and meta-analysis.

SEARCH METHODS

We searched the Cochrane Airways Register of Trials, MEDLINE, Embase, PsycINFO, CINAHL, AMED, proceedings of respiratory conferences, clinical trial registries and bibliographies of relevant studies. We conducted the latest search on 21 December 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing chronic NIV for at least five hours per night for three consecutive weeks or more (in addition to standard care) versus standard care alone, in people with COPD. Studies investigating people initiated on NIV in a stable phase and studies investigating NIV commenced after a severe COPD exacerbation were eligible, but we reported and analysed them separately. The primary outcomes were arterial blood gases, health-related quality of life (HRQL), exercise capacity (stable COPD) and admission-free survival (post-exacerbation COPD). Secondary outcomes for both populations were: lung function, COPD exacerbations and admissions, and all-cause mortality. For stable COPD, we also reported respiratory muscle strength, dyspnoea and sleep efficiency.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. After inclusion of a study, we requested the IPD. We analysed continuous and time-to-event data using linear- and cox-regression mixed-effect models with a random effect on study level. We analysed dichotomous IPD using generalised estimating equations. We adjusted all models for age and sex. We assessed changes in outcomes after three and 12 months.  We also conducted a meta-analysis on aggregated trial data.

MAIN RESULTS

We included 14 new RCTs in this review update, in addition to the seven previously included. Seventeen studies investigated chronic NIV in stable COPD and four studies investigated chronic NIV commenced after a severe COPD exacerbation. Three studies compared NIV to sham continuous positive airway pressure (2 to 4 cmH₂O). Seven studies used a nasal mask, one study used an oronasal mask and eight studies used both interfaces. Five studies did not report the interface. The majority of trials (20/21) were at high risk of performance bias due to an unblinded design. We considered 11 studies to have a low risk of selection bias and 13 to have a low risk of attrition bias. We collected and analysed the IPD from 13 stable COPD studies (n = 778, 68% of the participants included) and from three post-exacerbation studies (n = 364, 96% of the participants included). In the stable COPD group, NIV probably results in a minor benefit on the arterial partial pressure of oxygen (PaO₂) after three months (adjusted mean difference (AMD) 0.27 kPa, 95% CI 0.04 to 0.49; 9 studies, 271 participants; moderate-certainty evidence), but there was little to no benefit at 12 months (AMD 0.09 kPa, 95% CI -0.23 to 0.42; 3 studies, 171 participants; low-certainty evidence). The arterial partial pressure of carbon dioxide (PaCO₂) was reduced in participants allocated to NIV after three months (AMD -0.61 kPa, 95% CI -0.77 to -0.45; 11 studies, 475 participants; high-certainty evidence) and persisted up to 12 months (AMD -0.42 kPa, 95% CI -0.68 to -0.16; 4 studies, 232 participants; high-certainty evidence).  Exercise capacity was measured with the 6-minute walking distance (minimal clinical important difference: 26 m). There was no clinically relevant effect of NIV on exercise capacity (3 months: AMD 15.5 m, 95% CI -0.8 to 31.7; 8 studies, 330 participants; low-certainty evidence; 12 months: AMD 26.4 m, 95% CI -7.6 to 60.5; 3 studies, 134 participants; very low-certainty evidence). HRQL was measured with the Severe Respiratory Insufficiency and the St. Georges's Respiratory Questionnaire and may be improved by NIV, but only after three months (3 months: standardised mean difference (SMD) 0.39, 95% CI 0.15 to 0.62; 5 studies, 259 participants; very low-certainty evidence; 12 months: SMD 0.15, 95% CI -0.13 to 0.43; 4 studies, 200 participants; very low-certainty evidence). Lastly, the risk for all-cause mortality is likely reduced by NIV (adjusted hazard ratio (AHR) 0.75, 95% CI 0.58 to 0.97; 3 studies, 405 participants; moderate-certainty evidence). In the post-exacerbation COPD group, there was little to no benefit on the PaO₂ after three months, but there may be a slight decrease after 12 months (3 months: AMD -0.10 kPa, 95% CI -0.65 to 0.45; 3 studies, 234 participants; low-certainty evidence; 12 months: -0.27 kPa, 95% CI -0.86 to 0.32, 3 studies; 170 participants; low-certainty evidence). The PaCO₂ was reduced by NIV at both three months (AMD -0.40 kPa, 95% CI -0.70 to -0.09; 3 studies, 241 participants; moderate-certainty evidence) and 12 months (AMD -0.52 kPa, 95% CI -0.87 to -0.18; 3 studies, 175 participants; high-certainty evidence). NIV may have little to no benefit on HRQL (3 months: SMD 0.25, 95% CI -0.01 to 0.51; 2 studies, 219 participants; very low-certainty evidence; 12 months: SMD 0.25, 95% -0.06 to 0.55; 2 studies, 164 participants; very low-certainty evidence). Admission-free survival seems improved with NIV (AHR 0.71, 95% CI 0.54 to 0.94; 2 studies, 317 participants; low-certainty evidence), but the risk for all-cause mortality does not seem to improve (AHR 0.97, 95% CI 0.74 to 1.28; 2 studies, 317 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Regardless of the timing of initiation, chronic NIV improves daytime hypercapnia. In addition, in stable COPD, survival seems to be improved and there might be a short term HRQL benefit. In people with persistent hypercapnia after a COPD exacerbation, chronic NIV might prolong admission-free survival without a beneficial effect on HRQL. In stable COPD, future RCTs comparing NIV to a control group receiving standard care might no longer be warranted, but research should focus on identifying participant characteristics that would define treatment success. Furthermore, the optimal timing for initiation of NIV after a severe COPD exacerbation is still unknown.

Patient Satisfaction and Attainment of Patient-Specific Goals after Endobronchial Valve Treatment

Rationale: Bronchoscopic lung volume reduction with endobronchial valves (EBVs) significantly improves clinical outcomes in patients with severe emphysema. However, patient-reported outcomes like patient satisfaction and patient-specific treatment goals were never investigated.Objectives: To investigate the patient-satisfaction level 1 year after treatment and patient-specific goals before and 1 year after EBV treatment. Furthermore, the study aimed to investigate whether the level of patient satisfaction or change in goals was associated with change in the clinical outcome.Methods: We prospectively included patients who underwent EBV treatment as part of regular care in our hospital and asked patients to report and score their personal treatment goals on the patient-specific complaint (PSC) questionnaire at baseline and after 1 year of follow-up and to complete a patient-satisfaction questionnaire at 1 year of follow-up.Results: Of the 134 patients who were treated with EBV, 109 filled out the patient-satisfaction questionnaire and 88 filled out the PSC questionnaire at baseline and 1 year after treatment. When adjusting for the patients who were lost to follow-up, 91% of the patients in total would recommend the EBV treatment to other patients. Seventy-five percent of the patients were (very) satisfied with the treatment and 11% were (very) unsatisfied. The three most frequently reported patient-specific goals to improve were walking (reported by 77% of the patients), taking a shower/washing/getting dressed (35%), and completing household chores (32%). Both the total PSC questionnaire sum score (mean change, -6.01 ± 6.0) and all individual reported goals significantly improved 1 year after treatment (P < 0.001). Furthermore, a higher patient-satisfaction level and larger improvement in goals was significantly associated with an improvement in forced expiratory volume in 1 second, residual volume, dyspnea severity, and quality of life.Conclusions: We found that the patient-satisfaction level is high and patient-specific goals significantly improve 1 year after EBV treatment. We believe that the individual patient's goals are important in the process of shared decision-making before treatment, as they can be used to identify unrealistic expectations beforehand and prevent disappointment afterward.Clinical trial registered at clinicaltrials.gov (NCT02815683).

Effect of Breathing Oxygen-Enriched Air on Exercise Performance in Patients With Pulmonary Hypertension Due to Heart Failure With Preserved Ejection Fraction: A Randomized, Placebo-Controlled, Crossover Trial

Objective: To evaluate the effects of breathing oxygen-enriched air (oxygen) on exercise performance in patients with pulmonary hypertension due to heart failure with preserved ejection fraction (PH-HFpEF).

Methods: Ten patients with PH-HFpEF (five women, age 60 ± 9 y, mPAP 37 ± 14 mmHg, PAWP 18 ± 2 mmHg, PVR 3 ± 3 WU, resting SpO₂ 98 ± 2%) performed two-cycle incremental exercise tests (IET) and two constant-work-rate exercise test (CWRET) at 75% maximal work-rate (W_max), each with ambient air (FiO₂ 0.21) and oxygen (FiO₂ 0.5) in a randomized, single-blinded, cross-over design. The main outcomes were the change in W_max (IET) and cycling time (CWRET) with oxygen vs. air. Blood gases at rest and end-exercise, dyspnea by Borg CR10 score at end-exercise; continuous SpO₂, minute ventilation (V'E), carbon dioxide output (V'CO₂), and cerebral and quadricep muscle tissue oxygenation (CTO and QMTO) were measured.

Results: With oxygen vs. air, W_max (IET) increased from 94 ± 36 to 99 ± 36 W, mean difference (95% CI) 5.4 (0.9–9.8) W, p = 0.025, and cycling time (CWRET) from 532 ± 203 to 680 ± 76 s, +148 (31.8–264) s, p = 0.018. At end-exercise with oxygen, Borg dyspnea score and V'E/V'CO₂ were lower, whereas PaO₂ and end-tidal PaCO₂ were higher. Other parameters were unchanged.

Conclusion: Patients with PH-HFpEF not revealing resting hypoxemia significantly improved their exercise performance while breathing oxygen-enriched air along with less subjective dyspnea sensation, a better blood oxygenation, and an enhanced ventilatory efficiency. Future studies should investigate whether prolonged training with supplemental oxygen would increase the training effect and, potentially, daily activity for PH-HFpEF patients.

Clinical Trial Registration: [clinicaltrials.gov], identifier [NCT04157660].

The effect of pulmonary rehabilitation on physical performance and health related quality of life in patients with chronic lung disease

Pulmonary rehabilitation (PR) is a multidisciplinary approach that improves exercise capacity and health-related quality of life in patients with chronic lung disease. We retrospectively reviewed the medical records of the patients with chronic lung disease who participated in the PR program at University Medical Center in Lubbock, Texas, between 2014 and 2019. Clinical information, 6-min walk test (6 MW T) results, the number of emergency department (ED) visits and hospitalizations, and psychosocial questionnaires (CAT score, PHQ9 and mMRC dyspnea score) were recorded before and after the completion of the program. Multiple variable linear regression and logistic regression were used to analyze the relationships between patient characteristics and changes in the 6-min walk distance and the achievement of a minimal clinically important differences (MCID) in the 6-min walk distance, the CAT score, the PHQ-9, and the mMRC. 279 patients enrolled in pulmonary rehabilitation; 144 patients (52%) completed the program. After completion of the program, 84 patients increased their 6 MW T distance to exceed the MCID with a mean increase of 178 feet, and the number of ED visits and hospitalizations decreased from 0.80 ± 1.11 to 0.55 ± 0.87 (p < 0.05) in the six months before and after rehabilitation. There were statistically significant improvements in all three psychosocial scores. Factors associated with non-completion included younger age, female gender, and shorter baseline 6 MW T distances. The MCID helps evaluate patient outcomes following pulmonary rehabilitation and provide more definite assessment of benefits. The high dropout rate indicates that programs must continuously monitor patient participation and interest.

Bronchoscopic Valve Treatment of End-Stage Chronic Obstructive Pulmonary Disease

Endobronchial valve therapy has evolved over the past decade, with demonstration of significant improvements in pulmonary function, 6-minute walk distance, and quality of life in patients with end-stage chronic obstructive lung disease. Appropriate patient selection is crucial, with identification of the most diseased lobe and of a target lobe with minimal to no collateral ventilation. Endobronchial valve therapy typically is utilized in patients with heterogeneous disease but may be indicated in select patients with homogeneous disease. Morbidity and mortality have been lower than historically reported with lung volume reduction surgery, but complications related to pneumothoraces remain a challenge.

Haemoglobin as a biomarker for clinical outcomes in chronic obstructive pulmonary disease

In COPD, anaemia is associated with increased morbidity, but the relationship between haemoglobin over its entire observed range and morbidity is poorly understood. Such an understanding could guide future therapeutic targeting of haemoglobin in COPD management. Leveraging the COPDGene study, we conducted a cross-sectional analysis of haemoglobin from COPD participants, examining symptoms, quality of life, functional performance, and acute exacerbations of COPD (AECOPD). Haemoglobin was analysed both as a continuous variable and categorised into anaemia, normal haemoglobin, and polycythaemia groups. Fractional polynomial modelling was used for continuous analyses; categorical models were multivariable linear or negative binomial regressions. Covariates included demographics, comorbidities, emphysema, diffusing capacity, and airflow obstruction. From 2539 participants, 366 (14%) were identified as anaemic and 125 (5%) as polycythaemic. Compared with normal haemoglobin, anaemia was significantly associated with increased symptoms (COPD Assessment Test score: p=0.006, modified Medical Research Council (mMRC) Dyspnoea Score: p=0.001); worse quality of life (St. George's Respiratory Questionnaire (SGRQ) score: p<0.001; Medical Outcomes Study Short Form 36-item Questionnaire (SF-36) General Health: p=0.002; SF-36 Physical Health: p<0.001), decreased functional performance (6-min walk distance (6MWD): p<0.001), and severe AECOPD (p=0.01), while polycythaemia was not. Continuous models, however, demonstrated increased morbidity at both ends of the haemoglobin distribution (p<0.01 for mMRC, SGRQ, SF-36 Physical Health, 6MWD, and severe AECOPD). Evaluating interactions, both diffusing capacity and haemoglobin were independently associated with morbidity. We present novel findings that haemoglobin derangements towards either extreme of the observed range are associated with increased morbidity in COPD. Further investigation is necessary to determine whether haemoglobin derangement drives morbidity or merely reflects systemic inflammation, and whether correcting haemoglobin towards the normal range improves morbidity.

Evaluation of an Enhanced Pulmonary Rehabilitation Program: A Randomised Controlled Trial

RATIONALE

Pulmonary rehabilitation (PR) is the most effective strategy to improve health outcomes in people with COPD, although it has had limited success in promoting sustained physical activity. PR with a strong focus on disease self-management may better facilitate long-term behavior change.

OBJECTIVE

To compare a newly developed enhanced pulmonary rehabilitation program (EPR) to a traditional PR program on outcome achievement.

METHODS

In this randomized parallel-group controlled trial, PR classes were block randomized to EPR or traditional PR, which were delivered over 16 sessions each. The EPR incorporated new and updated "Living Well with COPD" education modules which had a stronger focus on chronic disease self-management. Fidelity of the intervention for content and delivery was assessed. Physical activity, self-efficacy, exercise tolerance, and health-related quality of life (HRQoL) were collected before, after, and 6-months following PR. Healthcare visits were collected 2 years before PR and 1 year after. Mortality was recorded 1 year after PR.

RESULTS

Of the 207 COPD patients enrolled, 108 received the EPR and 99 traditional PR. Physical activity (steps) and self-efficacy improved from pre- to post-PR in both programs, with no differences between groups. These effects were not sustained at 6 months. Exercise tolerance and HRQoL improved from pre- to post-PR with no between group differences, which were maintained at 6 months. Visits to primary care providers and respiratory specialists decreased in the EPR program relative to traditional PR. EPR was delivered as intended and there was no meaningful cross-contamination between the two programs.

CONCLUSIONS

Enhancing PR to have a greater emphasis on chronic disease self-management did not result in a superior improvement of physical activity and health outcomes compared to traditional PR except for reduced resource utilization from primary and specialist physician visits in the EPR program. Clinical trial registered with ClinicalTrials.gov (NCT02917915).