Influence of Lightweight Ambulatory Oxygen on Oxygen Use and Activity Patterns of COPD Patients Receiving Long-Term Oxygen Therapy

A Hybrid Effectiveness/Implementation Clinical Trial of Adherence to Long-Term Oxygen Therapy for Chronic Obstructive Pulmonary Disease

Rationale: Interventions to promote adherence to long-term oxygen therapy (LTOT) in chronic obstructive pulmonary disease (COPD) are needed. Objectives: To examine the real-world effectiveness of phone-based peer coaching on LTOT adherence and other outcomes in a pragmatic trial of patients with COPD. Methods: In a hybrid effectiveness/implementation pragmatic trial, patients were randomized to receive phone-based proactive coaching (educational materials, five phone-based peer coaching sessions over 60 d), reactive coaching (educational materials, peer coaching when requested), or usual care. Study staff members collected baseline and outcome data via phone at 30, 60, and 90 days after randomization. Adherence to LTOT over 60 days, the primary effectiveness outcome, was defined as mean LTOT use ⩾17.7 h/d. LTOT use was calculated using information about home oxygen equipment use in worksheets completed by study participants. Comparisons of adherence to LTOT between each coaching group and the usual care group using multivariable logistic regression models were prespecified as the primary analyses. Secondary effectiveness outcomes included Patient Reported Outcome Management Information System measures for physical, emotional, and social health. We assessed early implementation domains in the reach, adoption, and implementation framework. Results: In 444 participants, the proportions who were adherent to LTOT at 60 days were 74% in usual care, 84% in reactive coaching, and 70% in proactive coaching groups. Although reach, adoption by stakeholder partners, and intervention fidelity were acceptable, complete LTOT adherence data were available in only 73% of participants. Reactive coaching (adjusted odds ratio, 1.77; 97.5% confidence interval, 0.80-3.90) and proactive coaching (adjusted odds ratio, 0.70; 97.5% confidence interval, 0.34-1.46) did not improve adherence to LTOT compared with usual care. However, proactive coaching significantly reduced depressive symptoms and sleep disturbance compared with usual care and reduced depressive symptoms compared with reactive coaching. Unexpectedly, LTOT adherence was significantly lower in the proactive compared with the reactive coaching group. Conclusions: The results were inconclusive about whether a phone-based peer coaching strategy changed LTOT adherence compared with usual care. Further studies are needed to confirm the potential benefits of proactive peer coaching on secondary effectiveness outcomes and differences in LTOT adherence between proactive and reactive peer coaching. Clinical trial registered with ClinicalTrials.gov (NCT02098369).

Supplemental oxygen and noninvasive ventilation

The respiratory system attempts to maintain normal levels of oxygen and carbon dioxide. However, airflow limitation, parenchymal abnormalities and dysfunction of the respiratory pump may be compromised in individuals with advanced COPD, eventually leading to respiratory failure, with reduced arterial oxygen tension (hypoxaemia) and/or increased arterial carbon dioxide tension (P aCO2 ; hypercapnia). Hypoxaemia may persist in individuals with severe COPD despite smoking cessation and optimisation of pharmacotherapy. Long-term oxygen therapy (LTOT) can improve survival in those with severe daytime hypoxaemia, whereas those with less severe hypoxaemia may only have improved exercise capacity and dyspnoea. Changes in respiratory physiology that occur during sleep further predispose to hypoxaemia, particularly in individuals with COPD. However, the major cause of hypoxaemia is hypoventilation. Noninvasive ventilation (NIV) may reduce mortality and need for intubation in individuals with COPD and acute hypercapnic respiratory failure. However, NIV may also improve survival and quality of life in individuals with stable, chronic hypercapnia and is now suggested for those with prolonged hypercapnia (e.g. P aCO2 >55 mmHg 2-6 weeks after hospital discharge) when clinically stable and after optimisation of medical therapy including LTOT if indicated. Many questions remain about the optimal mode, settings and goal of NIV therapy.

Association between long-term oxygen therapy provided outside the guidelines and mortality in patients with COPD

INTRODUCTION

Hypoxaemia is a frequent complication of chronic obstructive pulmonary disease (COPD). To prevent its consequences, supplemental oxygen therapy is recommended by international respiratory societies. However, despite clear recommendations, some patients receive long-term oxygen therapy (LTOT), while they do not meet prescription criteria. While evidence suggests that acute oxygen supply at high oxygenation targets increases COPD mortality, its chronic effects on COPD mortality remain unclear. Thus, the study will aim to evaluate through a systematic review and individual patient data meta-analysis (IPD-MA), the association of LTOT prescription outside the guidelines on survival over time in COPD.

METHODS

Systematic review and IPD-MA will be conducted according to Preferred Reporting Items for a Systematic Review and Meta-Analyses IPD guidelines. Electronic databases (PubMed, Web of Science, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, OpenGrey and BioRxiv/MedRxix) will be scanned to identify relevant studies (cohort of stable COPD with arterial oxygen tension data available, with indication of LTOT filled out at the moment of the study and with a survival follow-up). The anticipated search dates are January-February 2022. The main outcome will be the association between LTOT and time to all-cause mortality according to hypoxaemia severity, after controlling for potential covariates and all available clinical characteristics. Quantitative data at the level of the individual patient will be used in a one-step approach to develop and validate a prognostic model with a Cox regression analysis. The one-step IPD-MA will be conducted to study the association and the moderators of association between supplemental oxygen therapy and mortality. Multilevel survival analyses using Cox-mixed effects models will be performed.

ETHICS AND DISSEMINATION

As a protocol for a systematic review, a formal ethics committee review is not required. Only studies with institutional approval from an ethics committee and anonymised IPD will be included. Results will be disseminated through peer-reviewed publications and presentations in conferences.

PROSPERO REGISTRATION NUMBER

CRD42020209823.

[Guideline for Long-Term Oxygen Therapy - S2k-Guideline Published by the German Respiratory Society]

Long-term oxygen therapy is of great importance both for reducing mortality and for improving performance in patients with chronic lung diseases. The prerequisites for Long-term oxygen therapy are adequate diagnostics and clearly defined indication. A causal distinction into chronic hypoxaemic and hypercapnic respiratory failure is reasonable, from which the differential indication for non-invasive ventilation results.The revised guideline covers the diagnostics and indication of chronic lung and heart diseases, the role of oxygen in terminal illness and gives a detailed description of available oxygen devices. The guideline is intended to help avoid undersupply, oversupply and false prescriptions. Furthermore, the chapter "Postacute Oxygen Therapy" discusses the procedure, relevant in everyday life, but not yet clearly defined, for prescribing oxygen therapy for the home at the end of an inpatient stay. Another important point, the correct prescription of mobile oxygen systems, is also presented in the guideline. This document is a revised version of the guideline for longterm oxygen therapy and replaces the version of 2008.

Interventions for promoting physical activity in people with chronic obstructive pulmonary disease (COPD)

BACKGROUND

Escalating awareness of the magnitude of the challenge posed by low levels of physical activity in people with chronic obstructive pulmonary disease (COPD) highlights the need for interventions to increase physical activity participation. The widely-accepted benefits of physical activity, coupled with the increasing availability of wearable monitoring devices to objectively measure participation, has led to a dramatic rise in the number and variety of studies that aimed to improve the physical activity of people with COPD. However, little was known about the relative efficacy of interventions tested so far.

OBJECTIVES

In people with COPD, which interventions are effective at improving objectively-assessed physical activity?

SEARCH METHODS

We identified trials from the Cochrane Airways Trials Register Register, which contains records identified from bibliographic databases including the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, AMED, and PsycINFO. We also searched PEDro, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform portal and the Australian New Zealand Clinical Trials Registry (from inception to June 2019). We checked reference lists of all primary studies and review articles for additional references, as well as respiratory journals and respiratory meeting abstracts, to identify relevant studies.

SELECTION CRITERIA

We included randomised controlled trials of interventions that used objective measures for the assessment of physical activity in people with COPD. Trials compared an intervention with no intervention or a sham/placebo intervention, an intervention in addition to another standard intervention common to both groups, or two different interventions.

DATA COLLECTION AND ANALYSIS

We used standard methods recommended by Cochrane. Subgroup analyses were possible for supervised compared to unsupervised pulmonary rehabilitation programmes in clinically-stable COPD for a range of physical activity outcomes. Secondary outcomes were health-related quality of life, exercise capacity, adverse events and adherence. Insufficient data were available to perform prespecified subgroup analyses by duration of intervention or disease severity. We undertook sensitivity analyses by removing studies that were at high or unclear risk of bias for the domains of blinding and incomplete outcome data.

MAIN RESULTS

We included 76 studies with 8018 participants. Most studies were funded by government bodies, although some were sponsored by equipment or drug manufacturers. Only 38 studies had physical activity as a primary outcome. A diverse range of interventions have been assessed, primarily in single studies, but improvements have not been systematically demonstrated following any particular interventions. Where improvements were demonstrated, results were confined to single studies, or data for maintained improvement were not provided. Step count was the most frequently reported outcome, but it was commonly assessed using devices with documented inaccuracy for this variable. Compared to no intervention, the mean difference (MD) in time in moderate- to vigorous-intensity physical activity (MVPA) following pulmonary rehabilitation was four minutes per day (95% confidence interval (CI) -2 to 9; 3 studies, 190 participants; low-certainty evidence). An improvement was demonstrated following high-intensity interval exercise training (6 minutes per day, 95% CI 4 to 8; 2 studies, 275 participants; moderate-certainty evidence). One study demonstrated an improvement following six months of physical activity counselling (MD 11 minutes per day, 95% CI 7 to 15; 1 study, 280 participants; moderate-certainty evidence), but we found mixed results for the addition of physical activity counselling to pulmonary rehabilitation. There was an improvement following three to four weeks of pharmacological treatment with long-acting muscarinic antagonist and long-acting beta2-agonist (LAMA/LABA) compared to placebo (MD 10 minutes per day, 95% CI 4 to 15; 2 studies, 423 participants; high-certainty evidence). These interventions also demonstrated improvements in other measures of physical activity. Other interventions included self-management strategies, nutritional supplementation, supplemental oxygen, endobronchial valve surgery, non-invasive ventilation, neuromuscular electrical stimulation and inspiratory muscle training.

AUTHORS' CONCLUSIONS

A diverse range of interventions have been assessed, primarily in single studies. Improvements in physical activity have not been systematically demonstrated following any particular intervention. There was limited evidence for improvement in physical activity with strategies including exercise training, physical activity counselling and pharmacological management. The optimal timing, components, duration and models for interventions are still unclear. Assessment of quality was limited by a lack of methodological detail. There was scant evidence for a continued effect over time following completion of interventions, a likely requirement for meaningful health benefits for people with COPD.

Physical Activity in Patients with Chronic Obstructive Pulmonary Disease on Long-Term Oxygen Therapy: A Cross-Sectional Study

Background and aim

There are few studies evaluating physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) on long-term oxygen therapy (LTOT).

Aim

To assess PA in hypoxemic COPD patients on LTOT.

Methods

In this cross-sectional study, we compared lung function, arterial blood gases, respiratory and peripheral muscle strength, 6-min walking distance (6MWD), daily energy expenditure and steps, and health-related quality of life (HRQL) in COPD patients on LTOT (LTOT group) versus two groups of control patients not needing LTOT: with (HYPOX) and without (COPD) exercise-induced desaturations.

Results

Groups did not differ as regards demographics, anthropometrics, peripheral or respiratory muscle strength. Compared to the other groups, LTOT patients had more severe airway obstruction and lung hyperinflation, greater number and severity of comorbidities, shorter 6MWD, as well as lower mean SpO₂ during 6MWD and worse quality of life. LTOT patients had a lower daily energy expenditure, shorter time spent > 3.0 METs and longer sedentary time compared to the COPD group, and less daily steps compared to the other groups. No significant difference in any parameter of PA was found between COPD and HYPOX. In LTOT patients, daily steps showed a strong correlation with 6MWD, and a moderate correlation with airway obstruction, level of oxygenation, comorbidities and quality of life but not with peripheral and respiratory muscle strength. In COPD and HYPOX patients, daily steps were strongly correlated with 6MWD and level of oxygenation as assessed by PaO₂/FiO₂. There was no significant correlation between mean SpO₂ and 6MWD in any group.

Conclusion

COPD patients on LTOT perform less physical activity than patients not needing LTOT, both with and without exercise-induced desaturations. Patients with exercise-induced desaturations do not perform less physical activity than those without.

Optimizing Home Oxygen Therapy. An Official American Thoracic Society Workshop Report

More than 1.5 million adults in the United States use supplemental oxygen for a variety of respiratory disorders to improve their quality of life and prolong survival. This document describes recommendations from a multidisciplinary workshop convened at the ATS International Conference in 2017 with the goal of optimizing home oxygen therapy for adults. Ideal supplemental oxygen therapy is patient-specific, provided by a qualified clinician, includes an individualized prescription and therapeutic education program, and offers oxygen systems that are safe, promote mobility, and treat hypoxemia. Recently, patients and clinicians report a growing number of problems with home oxygen in the United States. Oxygen users experience significant functional, mechanical, and financial problems and a lack of education related to their oxygen equipment-problems that impact their quality of life. Health care providers report a lack of readily accessible resources needed to prescribe oxygen systems correctly and efficiently. Patients with certain lung diseases are affected more than others because of physically unmanageable or inadequate portable systems. Analysis is needed to quantify the unintended impact that the Centers for Medicare and Medicaid Services Competitive Bidding Program has had on patients receiving supplemental oxygen from durable medical equipment providers. Studies using effectiveness and implementation research designs are needed to develop and evaluate new models for patient education, identify effective ways for stakeholders to interface, determine the economic benefit of having respiratory therapists perform in-home education and follow-up testing, and collaborate with technology companies to improve portable oxygen devices. Generation of additional evidence of the benefit of supplemental oxygen across the spectrum of advanced lung diseases and the development of clinical practice guidelines should both be prioritized.

Oxygen devices and delivery systems

Oxygen use has extended from inpatient to outpatient settings for patients with chronic pulmonary diseases and complications of hypoxaemia. This article presents an overview of oxygen devices (oxygen concentrators, compressed gas cylinders and liquid oxygen) and delivery systems (high- and low-flow). The indications, advantages and disadvantages of each device and delivery system are presented, aiming to offer updated knowledge to the multidisciplinary team members managing patients with respiratory failure, and therefore allowing appropriate selection of devices and delivery systems that are tailored to the needs of each patient.

Oxygen therapy in COPD and interstitial lung disease: navigating the knowns and unknowns

Domiciliary oxygen therapy is often prescribed for patients with hypoxaemia due to advanced lung disease, most commonly chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD). Long-term oxygen therapy (LTOT) trials conducted in patients with COPD in the 1980s remain the basis for clinical decisions and guideline recommendations regarding LTOT for patients with non-COPD conditions as there is a lack of high-quality evidence concerning its use in the non-COPD population. There is also a lack of evidence for the use of ambulatory and nocturnal oxygen therapy in patients with isolated exertional and nocturnal hypoxaemia. These deficiencies pose significant challenges in patient care, with consequent discrepancies in guideline recommendations and clinical approaches. In recent years, new studies have been and are currently being conducted to fill the gaps in our understanding and use of domiciliary oxygen therapy for other indications, including ILD. This article provides a comparison of the epidemiology and significance of hypoxaemia in patients with COPD and ILD, with an up-to-date review of current evidence regarding the role of different types of domiciliary oxygen therapy in these conditions.

Despite the significance of hypoxaemia in patients with chronic lung diseases, an up-to-date review shows current evidence for clinical use of domiciliary oxygen therapy remains limitedhttp://bit.ly/33aW31n

Home Oxygen in Chronic Obstructive Pulmonary Disease

Two landmark trials conducted more than 35 years ago provided scientific evidence that, under very specific circumstances, long-term oxygen therapy (LTOT) may prolong life. These two trials enrolled 290 patients with chronic obstructive pulmonary disease and severe daytime hypoxemia documented by direct arterial blood gas measurement. From that time, LTOT became a standard of care, and the indications for oxygen therapy expanded to include nocturnal oxygen therapy for isolated nocturnal oxygen desaturation, ambulatory oxygen to correct exercise-induced desaturation, and short-burst oxygen to relieve dyspnea. In most cases, the rationale for broadening the indications for oxygen therapy is that, if hypoxemia exists, correcting it by increasing the Fi_O2 should help. However, with the exception of LTOT in severely hypoxemic patients with chronic obstructive pulmonary disease, randomized controlled trials of oxygen therapy have failed to demonstrate clinically significant benefits. Also, adherence to LTOT is usually suboptimal. Important areas for future research include improving understanding of the mechanisms of action of supplemental oxygen, the clinical and biochemical predictors of responsiveness to LTOT, the methods for measuring and enhancing adherence to LTOT, and the cost-effectiveness of oxygen therapy. A standardization of terminology to describe the use of supplemental oxygen at home is provided.

Clinician Strategies to Improve the Care of Patients Using Supplemental Oxygen

This article reviews four key clinician strategies to improve the care of adult patients receiving supplemental oxygen in the outpatient setting in the United States. The current barriers to adequate oxygen services are substantial and complex and include decreased reimbursement to durable medical equipment (DME) companies; a substantially lower number of available DME suppliers; difficult communication with DME suppliers; rigid patient testing, prescription, and documentation requirements; and unclear patient benefit and adherence. Recent data documenting frequent and varied problems reflect the significant impact of supplemental oxygen therapy on patients and caregivers. Areas where clinicians can improve patient oxygen experiences are highlighted in this review and include understanding Centers for Medicare and Medicaid Services oxygen prescription requirements, matching oxygen equipment to patient needs, providing essential patient education, and understanding mechanisms for patients and clinicians to report unresolved oxygen problems.

A telephone-based survey of current trends, habits and beliefs in patients receiving portable oxygen therapy in Madrid, Spain

Portable oxygen therapy is a major challenge for patients and clinicians. Additionally, the available evidence on this subject is poor considering that only a few studies have been published and the results have not been encouraging. We explored the current trends, habits and beliefs among patients receiving portable oxygen therapy in a geographical area of Madrid, Spain (4 051 862 inhabitants).

A telephone-based survey was conducted among patients selected from a database who were undergoing portable oxygen therapy.

The number of patients on home respiratory therapies on December 31, 2017 was 81 559 (prevalence 2013.30 per 100 000 inhabitants). A total of 19 492 patients were on home oxygen therapy (HOT) (prevalence 481.16 per 100 000 inhabitants). Of these, 4015 patients (20% of the total of patients on HOT) received ambulatory oxygen therapy. In the analysed period, 1942 patients were selected (57.31% male and 42.69% female). The mean±sd age was 73.89±11.67 years. Most of patients had portable oxygen concentrators (99.59%). The survey was completed by 1777 patients. Most of patients thought they had been prescribed HOT for respiratory failure. 55% of the participants surveyed reported having carried out a walking test with oxygen to know the amount of oxygen they needed. 71% of the participants reported leaving the home for between 1 and 3 h a day. Most of them were carrying portable devices in a wheeled cart (51.94%).

Our study data obtained from a large sample of oxygen-dependent individuals provide valuable information regarding domiciliary and portable oxygen usage in Madrid.

A telephone survey was conducted in patients undergoing portable oxygen therapy. Data from a large sample of patients show us that they have a good training in ambulatory oxygen use.http://bit.ly/2Z6mP94

Characteristics at the time of oxygen initiation associated with its adherence: Findings from the COPD Long-term Oxygen Treatment Trial

RATIONALE

Characteristics associated with adherence to long-term oxygen therapy (LTOT) in COPD remain unclear.

OBJECTIVES

To identify patient characteristics at the time of oxygen initiation associated with its adherence.

METHODS

We conducted a secondary analysis of data from 359 COPD participants assigned to oxygen in the Long-term Oxygen Treatment Trial. Participants were prescribed continuous (n = 214) or intermittent (n = 145) oxygen based on desaturation patterns at study entry. At the time of initial prescription, participants rated their perceived readiness, confidence, and importance to use oxygen on a 0-10 scale (0 = not at all, 10 = very much). During follow-up, they self-reported average hours per day of use (adherence). Adherence was averaged over short-term (0-30 days), medium-term (months 9-12), and long-term (month 13 to last follow-up) intervals. Multivariable logistic regression models explored characteristics associated with high adherence (≥16 h/day [continuous] or ≥8 h/day [intermittent]) during each time interval.

RESULTS

Participant readiness, confidence, and importance at the time of oxygen initiation were associated with high short- and medium-term adherence. For each unit increase in baseline readiness, the odds of high short-term adherence increased by 21% (odds ratio [OR] 1.21, 95% confidence interval [CI] 1.05-1.40) and 94% (OR 1.94, 95% CI 1.45-2.59) in the continuous and intermittent groups, respectively. In both groups, high adherence in the medium-term was associated with high adherence in the long-term (continuous, OR 12.49, 95% CI 4.90-31.79; intermittent, OR 38.08, 95% CI 6.96-208.20).

CONCLUSIONS

Readiness, confidence, and importance to use LTOT at initiation, and early high adherence, are significantly associated with long-term oxygen adherence.

Incorporating telemedicine into the integrated care of the COPD patient a summary of an interdisciplinary workshop held in Stresa, Italy, 7-8 September 2017

This report is a summary of a workshop focusing on using telemedicine to facilitate the integrated care of chronic obstructive pulmonary disease (COPD). Twenty-five invited participants from 8 countries met for one and one-half days in Stresa, Italy on 7-8 September 2017, to discuss this topic. Participants included physiotherapists, nurses, a nurse practitioner, and physicians. While evidence-based data are always at the center of sound inference and recommendations, at this point in time the science behind telemedicine in COPD remains under-developed; therefore, this document reflects expert opinion and consensus. While telemedicine has great potential to expand and improve the care of our COPD patients, its application is still in its infancy. While studies have demonstrated its effectiveness in some patient-centered outcomes, the results are by no means consistently positive. Whereas this tool may potentially reduce health care costs by moving some medical interventions from centralized locations in to patient's home, its cost-effectiveness has had mixed results and telemonitoring has yet to prove its worth in the COPD population. These discordant results should not be unexpected in view of patient complexity and the heterogeneity of telemedicine. This is reflected in the very limited support offered by the National Health Services to a wider application of telemedicine in the integrated care of COPD patients. However, this situation should challenge us to develop the necessary science to clarify the role of telemedicine in the medical management of our patients, providing a better and definitive scientific basis to this approach.

Home oxygen therapy: re-thinking the role of devices

INTRODUCTION

A range of devices are available for delivering and monitoring home oxygen therapy (HOT). Guidelines do not give indications for the choice of the delivery device but recommend the use of an ambulatory system in subjects on HOT whilst walking. Areas covered: We provide a clinical overview of HOT and review traditional and newer delivery and monitoring devices for HOT. Despite relevant technology advancements, clinicians, faced with many challenges when they prescribe oxygen therapy, often remain familiar to traditional devices and continuous flow delivery of oxygen. Some self-filling delivery-less devices could increase the users' level of independence with ecological advantage and, perhaps, reduced cost. Some newer portable oxygen concentrators are being available, but more work is needed to understand their performances in different diseases and clinical settings. Pulse oximetry has gained large diffusion worldwide and some models permit long-term monitoring. Some closed-loop portable monitoring devices are also able to adjust oxygen flow automatically in accordance with the different needs of everyday life. This might help to improve adherence and the practice of proper oxygen titration that has often been omitted because difficult to perform and time-consuming. Expert commentary: The prescribing physicians should know the characteristics of newer devices and use technological advancements to improve the practice of HOT.

Perceived Satisfaction With Long-Term Oxygen Delivery Devices Affects Perceived Mobility and Quality of Life of Oxygen-Dependent Individuals With COPD

BACKGROUND

Although routine physical activity for individuals with COPD is recommended, there are inherent limitations of available oxygen delivery devices that may result in hypoxemia during activity. Changes in Medicare laws have resulted in an increased use of oxygen cylinders and a reduction in the use of liquid oxygen devices. The aim of this survey was to assess the impact of perceived satisfaction with various oxygen delivery devices on perceived mobility and quality of life (QOL) of oxygen-dependent subjects with COPD.

METHODS

A survey was developed to measure perceived satisfaction with current portable oxygen delivery devices, perceived mobility, and perceived QOL. The survey was deployed via a link posted on the COPD Foundation's COPD360SOCIAL social media site for 5 weeks, which resulted in the recruitment of 529 participants, of which 417 were included in the data analysis.

RESULTS

Quantile regression analysis revealed that the median perceived device satisfaction score was significantly higher in the liquid oxygen device group (P < .001) compared with the portable oxygen cylinder and portable oxygen concentrator (POC) groups. The median perceived mobility score was significantly higher in the liquid oxygen device group (P < .001) compared with the portable oxygen cylinder group, but not the POC group. The median QOL score was significantly higher in the liquid oxygen device group (P < .001) compared with the POC and portable oxygen cylinder groups. Moreover, partial least-squares structural equation modeling regression analysis showed that perceived mobility is significantly affected by perceived satisfaction with the long-term oxygen therapy (LTOT) device (adjusted R² = 0.15, P < .001), and perceived QOL is significantly affected by both perceived satisfaction with the LTOT device and perceived mobility (adjusted R² = 0.45, P < .001).

CONCLUSIONS

For individuals with COPD requiring LTOT, perceived satisfaction with a portable LTOT device significantly and positively affects perceived mobility and QOL.

Home oxygen therapy: evidence versus reality

INTRODUCTION

LTOT is a well-established treatment option for hypoxemic patients. Scientific evidence for its benefits of LTOT dates back to the 1980s, when two randomized controlled trials showed prolonged survival in COPD-patients undergoing LTOT for at least 15 hours/day. In contrast, the potential benefits of LTOT in non-COPD-patients has not been well researched and the recommendations for its application are primarily extrapolated from trials on COPD-patients. Recently, a large trial confirmed that COPD-patients who don't meet classic indication criteria, and have moderate desaturation at rest or during exercise, do not benefit from oxygen therapy. Also the significant technical evolution of LTOT devices has improved its application. Areas covered: A literature research was performed in pubmed regarding home oxygen therapy (terms: LTOT, ambulatory oxygen therapy, short burst oxygen therapy, nocturnal oxygen therapy). Expert commentary: LTOT proved a survival benefit for COPD patients about 30 years ago. Whether the results of these trials are still valid for patients under modern treatment guidelines remains unknown. Nevertheless, the classic indication criteria for LTOT still persist in guidelines, since there is a lack of updated evidence for the effects of LTOT in more severe hypoxemic patients.

Patient Involvement in the Design of a Patient-Centered Clinical Trial to Promote Adherence to Supplemental Oxygen Therapy in COPD

BACKGROUND

Patients are increasingly viewed as key stakeholders who can contribute in meaningful ways to clinical research and are emphasized in research funded by the Patient-Centered Outcomes Research Institute (PCORI). We are not aware of other peer-reviewed publications that report methods and outcomes of patient engagement to refine study design for a PCORI-sponsored clinical effectiveness trial.

OBJECTIVE

The aim of this report was to describe the process and outcomes of involving patients in the design of a clinical trial to promote adherence to supplemental oxygen therapy among patients with chronic obstructive pulmonary disease.

METHODS

In-person focus groups and individual discussions via telephone and email were used to elicit feedback to refine the intervention and clarify outcomes of highest importance to patients.

RESULTS

A total of 25 patients and five caregivers provided feedback. Their feedback has informed decisions regarding the length of intervention sessions (20 min and in some cases longer was acceptable), the importance of including caregivers, and discussion topics (e.g., social discomfort about using oxygen in public, identifying personally relevant reasons to use oxygen, pulmonary rehabilitation). Multiple outcomes were rated as highly important to patients (physical function, fatigue, sleep, anxiety, depression, and ability to participate in social roles and activities), and the outcome that was ranked as most important varied by individual. Therefore, multiple patient-reported outcomes will be used as endpoints for the clinical trial.

CONCLUSIONS

Patient involvement led to refinements of the intervention and clinical trial endpoints to better address the expressed needs and concerns of patients and caregivers.

Oxygen therapy devices and portable ventilators for improved physical activity in daily life in patients with chronic respiratory disease

INTRODUCTION

Patients with hypoxemia and chronic respiratory failure may need to use oxygen therapy to correct hypoxemia and to use ventilatory support to augment alveolar ventilation, reverse abnormalities in blood gases (in particular hypercapnia) and reduce the work of breathing. Areas covered: This narrative review provides an overview on the use of oxygen therapy devices or portable ventilators for improved physical activity in daily life (PADL) as well as discusses the issue of lower mobility in daily life among stable patients with chronic respiratory disease who present indication for long-term oxygen therapy (LTOT) or home-based noninvasive ventilation (NIV). A literature review of these concepts was performed by using all related search terms. Expert commentary: Technological advances led to the development of light and small oxygen therapy devices and portable ventilators which aim to facilitate patients' mobility and ambulation. However, the day-by-day dependence of a device may reduce mobility and partially impair patients' PADL. Nocturnal NIV implementation in hypercapnic patients seems promising to improve PADL. The magnitude of their equipment-related physical inactivity is underexplored up to this moment and more long-term randomized clinical trials and meta-analysis examining the effects of ambulatory oxygen and NIV on PADL are required.

Why Don't Our Patients with Chronic Obstructive Pulmonary Disease Listen to Us? The Enigma of Nonadherence

Nonadherence--not taking pharmacologic or nonpharmacologic treatments according to agreed recommendations from a health care provider--is common in patients with chronic obstructive pulmonary disease. Nonadherence in taking maintenance medications, smoking cessation, maintaining regular physical activity and exercise, starting and staying in pulmonary rehabilitation and continuing on with the postrehabilitation exercise/activity prescription, and successfully following self-management directions results in adverse outcomes across multiple areas. These include a faster decline in airway function, higher symptom burden, impaired health status, and increased health care use and mortality risk. Although nonadherence can also occur in health care providers (not following established treatment guidelines), this perspective focuses on patient nonadherence. Factors such as social/economic, health system, therapy-related, patient-related, and condition-related factors all impact this problem. To improve patient adherence, we need to consider these factors in the context of people with chronic obstructive pulmonary disease and implement strategies directly targeting underlying issues. Strategies may include customizing and simplifying learning and intervention regimes, identifying barriers to adherence and addressing them, ensuring patient support structures are in place, and improving self-efficacy. Future directions should focus on research and development in educational design; use of technology to assist education; psychological intervention strategies to support learning, motivation, self-efficacy and behavior change; and ways to improve healthcare providers' engagement with patients.

Exercise training alone or with the addition of activity counseling improves physical activity levels in COPD: a systematic review and meta-analysis of randomized controlled trials

Background

Physical inactivity is associated with poor outcomes in COPD, and as a result, interventions to improve physical activity (PA) are a current research focus. However, many trials have been small and inconclusive.

Objective

The aim of this systematic review and meta-analysis was to study the effects of randomized controlled trials (RCTs) targeting PA in COPD.

Methods

Databases (Physiotherapy Evidence Database [PEDro], Embase, MEDLINE, CINAHL and the Cochrane Central Register for Controlled Trials) were searched using the following keywords: “COPD”, “intervention” and “physical activity” from inception to May 20, 2016; published RCTs that aimed to increase PA in individuals with COPD were included. The PEDro scale was used to rate study quality. Standardized mean differences (effect sizes, ESs) with 95% confidence intervals (CIs) were determined. Effects of included interventions were also measured according to the minimal important difference (MID) in daily steps for COPD (599 daily steps).

Results

A total of 37 RCTs with 4,314 participants (mean forced expiratory volume in one second (FEV₁) % predicted 50.5 [SD=10.4]) were identified. Interventions including exercise training (ET; n=3 studies, 103 participants) significantly increased PA levels in COPD compared to standard care (ES [95% CI]; 0.84 [0.44–1.25]). The addition of activity counseling to pulmonary rehabilitation (PR; n=4 studies, 140 participants) showed important effects on PA levels compared to PR alone (0.47 [0.02–0.92]), achieving significant increases that exceeded the MID for daily steps in COPD (mean difference [95% CI], 1,452 daily steps [549–2,356]). Reporting of methodological quality was poor in most included RCTs.

Conclusion

Interventions that included ET and PA counseling during PR were effective strategies to improve PA in COPD.

An in silico analysis of oxygen uptake of a mild COPD patient during rest and exercise using a portable oxygen concentrator

Oxygen treatment based on intermittent-flow devices with pulse delivery modes available from portable oxygen concentrators (POCs) depends on the characteristics of the delivered pulse such as volume, pulse width (the time of the pulse to be delivered), and pulse delay (the time for the pulse to be initiated from the start of inhalation) as well as a patient's breathing characteristics, disease state, and respiratory morphology. This article presents a physiological-based analysis of the performance, in terms of blood oxygenation, of a commercial POC at different settings using an in silico model of a COPD patient at rest and during exercise. The analysis encompasses experimental measurements of pulse volume, width, and time delay of the POC at three different settings and two breathing rates related to rest and exercise. These experimental data of device performance are inputs to a physiological-based model of oxygen uptake that takes into account the real dynamic nature of gas exchange to illustrate how device- and patient-specific factors can affect patient oxygenation. This type of physiological analysis that considers the true effectiveness of oxygen transfer to the blood, as opposed to delivery to the nose (or mouth), can be instructive in applying therapies and designing new devices.

Interventions to modify physical activity in patients with COPD: a systematic review

The broad range of interventions to increase physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) has not been systematically assessed. We aimed to perform a systematic review of the interventional studies that have assessed PA as an outcome in patients with COPD.

A systematic search in five different databases (Medline, Embase, PsycINFO, CINAHL and Web of Science) was performed in March 2015. Two independent reviewers analysed the studies against the inclusion criteria (COPD defined by spirometry; prospective, randomised/nonrandomised studies, cohort and experimental studies with interventions using PA as an outcome), extracted the data and assessed the quality of evidence.

60 studies were included. Seven intervention groups were identified. PA counselling increased PA levels in COPD, especially when combined with coaching. 13 studies showed positive effects of pulmonary rehabilitation (PR) on PA, while seven studies showed no changes. All three PR programmes >12 weeks in duration increased PA. Overall, the quality of evidence was graded as very low.

Interventions focusing specifically on increasing PA, and longer PR programmes, may have greater impacts on PA in COPD. Well-designed clinical trials with objective assessment of PA in COPD patients are needed.

Ambulatory Oxygen for Exercise-Induced Desaturation and Dyspnea in Chronic Obstructive Pulmonary Disease (COPD): Systematic Review and Meta-Analysis

Introduction: Ambulatory oxygen therapy is indicated in patients that use long term oxygen therapy (LTOT) and current guidelines suggest its use in patients who exhibit exertional desaturation if there is a demonstrable improvement in exercise capacity. Evidence for this is largely derived from single assessment studies which have shown clear benefit in this setting when oxygen versus air is used. The long term effects, however, of ambulatory oxygen therapy in this particular group of patients is controversial. Methods: We conducted a systematic review of published literature from 1980 to June 2014 for trials in which ambulatory oxygen was compared to placebo in chronic obstructive pulmonary disease (COPD) patients not on LTOT. We also reviewed the effectiveness of devices delivering ambulatory oxygen. Outcome measures were focused towards exercise capacity, Borg scores and the ability of the delivery devices to maintain oxygen saturations on exercise. Results: Twenty three studies (620 patients) were included in the review. Nine studies evaluated the clinical effectiveness of ambulatory oxygen and 14 studies evaluated the impact of the delivery devices. Ambulatory oxygen had no statistical effect on improving exercise capacity when assessed by the 6-minute walk test (6MWT) or the endurance shuttle walk test (ESWT);p=0.44 and p=0.29 respectively. End of test Borg scores showed no statistical improvement with ambulatory oxygen therapy during 6MWT (p=0.68). Oxygen conserving devices significantly improved oxygen saturations on exercise compared with continuous flow nasal cannulae (p=0.04). Conclusion: Ambulatory oxygen therapy has limited long term benefit in improving functional exercise capacity or Borg dyspnea scores.

An official European Respiratory Society statement on physical activity in COPD

This European Respiratory Society (ERS) statement provides a comprehensive overview on physical activity in patients with chronic obstructive pulmonary disease (COPD). A multidisciplinary Task Force of experts representing the ERS Scientific Group 01.02 "Rehabilitation and Chronic Care" determined the overall scope of this statement through consensus. Focused literature reviews were conducted in key topic areas and the final content of this Statement was agreed upon by all members. The current knowledge regarding physical activity in COPD is presented, including the definition of physical activity, the consequences of physical inactivity on lung function decline and COPD incidence, physical activity assessment, prevalence of physical inactivity in COPD, clinical correlates of physical activity, effects of physical inactivity on hospitalisations and mortality, and treatment strategies to improve physical activity in patients with COPD. This Task Force identified multiple major areas of research that need to be addressed further in the coming years. These include, but are not limited to, the disease-modifying potential of increased physical activity, and to further understand how improvements in exercise capacity, dyspnoea and self-efficacy following interventions may translate into increased physical activity. The Task Force recommends that this ERS statement should be reviewed periodically (e.g. every 5-8 years).

Ambulatory oxygen for people with chronic obstructive pulmonary disease who are not hypoxaemic at rest

BACKGROUND

People with chronic obstructive pulmonary disease (COPD) often become transiently hypoxaemic (low oxygen levels in blood) on exercise, necessitating oxygen therapy to improve breathlessness and exercise capacity and to reduce disability. Ambulatory oxygen therapy refers to provision of oxygen therapy during exercise and activities of daily living. Ambulatory oxygen therapy is often used by patients on long-term oxygen therapy (LTOT) during exercise or by non-LTOT users with or without resting hypoxaemia when they show evidence of exercise de-saturation and demonstrate improvement in exercise capacity with supplemental oxygen.

OBJECTIVES

To determine the longer-term efficacy of ambulatory oxygen therapy only in patients with COPD who do not meet the criteria for LTOT, with respect to improvement in exercise capacity, mortality, quality of life and other relevant measures of improvement.

SEARCH METHODS

The Cochrane Airways Group Specialised Register, including MEDLINE, EMBASE and CINAHL, was searched. Online clinical trial registers, including Controlled Clinical Trials (www.controlled-trials.com), government registries (clinicaltrials.gov) and World Health Organization (WHO) registries (www.who.int/trialsearch), were screened for ongoing and recently completed studies. Bibliographies of included studies were searched for additional trials that may meet the inclusion criteria and were not retrieved by the above search strategy. Authors of identified trials were contacted to provide other published and unpublished studies. Searches were current as of November 2012.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compare ambulatory oxygen therapy provided through portable oxygen cylinders/battery-powered devices or liquid oxygen canisters versus placebo air cylinders, usual medical care or co-intervention in study participants with COPD who did not meet criteria for LTOT.

DATA COLLECTION AND ANALYSIS

We used standard methods as expected by The Cochrane Collaboration.

MAIN RESULTS

Four studies met the inclusion criteria (331 participants), with two studies producing a statistically and clinically significant benefit in favour of the intervention for dyspnoea post exercise.The quality of life domain for all four included studies produced a statistically significant benefit for the subcategories of dyspnoea and fatigue, in favour of the oxygen group (dyspnoea mean difference (MD) 0.28, 95% confidence interval (CI) 0.10 to 0.45; P value 0.002; fatigue MD 0.17, 95% CI 0.04 to 0.31; P value 0.009). No evidence of any effect was reported for survival, and limited benefits were observed for exercise capacity (as measured by step test and distance walk test), with one study showing a statistically significant improvement in the number of steps taken in the oxygen group for group N-of-1 studies only. No other statistically significant benefits were observed for exercise capacity among the other trials or individual N-of-1 studies.

AUTHORS' CONCLUSIONS

In patients with COPD with moderate hypoxia, current evidence on ambulatory oxygen therapy reveals improvements in dyspnoea post exercise and in the dyspnoea and fatigue domain of quality of life. However, evidence for the clinical utility and effectiveness of ambulatory oxygen in improving mortality and exercise capacity was not evident in this review. Methodologically rigorous RCTs with sufficient power to detect a difference are required to investigate the role of ambulatory oxygen in the management of COPD.

Patients with COPD with higher levels of anxiety are more physically active

BACKGROUND

Physical activity (PA) has been found to be an excellent predictor of mortality beyond traditional measures in COPD. We aimed to determine the association between depression and anxiety with accelerometry-based PA in patients with COPD.

METHODS

We performed a cross-sectional analysis of baseline data from 148 stable patients with COPD enrolled in an ongoing, longitudinal, observational study. We measured PA (total daily step count) with a Stepwatch Activity Monitor over 7 days, depression and anxiety with the Hospital Anxiety and Depression Scales (HADSs), dyspnea with the Shortness of Breath Questionnaire, and functional capacity with the 6-min walk test.

RESULTS

Increased anxiety was associated with higher levels of PA such that for every one-point increase in the HADS-Anxiety score there was a corresponding increase of 288 step counts per day (β=288 steps, P<.001), after adjusting for all other variables. Higher levels of depressive symptoms were associated with lower PA (β=-176 steps, P=.02) only when anxiety was in the model. The interaction term for anxiety and depression approached significance (β=26, P=.10), suggesting that higher levels of anxiety mitigate the negative effects of depression on PA.

CONCLUSIONS

The increased PA associated with anxiety in COPD is, to our knowledge, a novel finding. However, it is unclear whether anxious patients with COPD are more restless, and use increased psychomotor activity as a coping mechanism, or whether those with COPD who push themselves to be more physically active experience more anxiety symptoms. Future studies should evaluate for anxiety and PA to better inform how to improve clinical outcomes.

TRIAL REGISTRY

Clinicaltrials.gov; No.: NCT01074515; URL: www.clinicaltrials.gov.