Prognostication of co-morbidity clusters on hospitalisation and mortality in advanced COPD.

RATIONALE: As the prevalence of multimorbidity increases, understanding the impact of isolated comorbidities in people COPD becomes increasingly challenging. A simplified model of common comorbidity patterns may improve outcome prediction and allow targeted therapy. OBJECTIVES: To assess whether comorbidity phenotypes derived from routinely collected clinical data in people with COPD show differences in risk of hospitalisation and mortality. METHODS: Twelve clinical measures related to common comorbidities were collected during annual reviews for people with advanced COPD and k-means cluster analysis performed. Cox proportional hazards with adjustment for covariates was used to determine hospitalisation and mortality risk between clusters. MEASUREMENTS AND MAIN RESULTS: In 203 participants (age 66 ± 9 years, 60 % male, FEV1%predicted 31 ± 10 %) no comorbidity in isolation was predictive of worse admission or mortality risk. Four clusters were described: cluster A (cardiometabolic and anaemia), cluster B (malnourished and low mood), cluster C (obese, metabolic and mood disturbance) and cluster D (less comorbid). FEV1%predicted did not significantly differ between clusters. Mortality risk was higher in cluster A (HR 3.73 [95%CI 1.09-12.82] p = 0.036) and B (HR 3.91 [95%CI 1.17-13.14] p = 0.027) compared to cluster D. Time to admission was highest in cluster A (HR 2.01 [95%CI 1.11-3.63] p = 0.020). Cluster C was not associated with increased risk of mortality or hospitalisation. CONCLUSIONS: Despite presence of advanced COPD, we report striking differences in prognosis for both mortality and hospital admissions for different co-morbidity phenotypes. Objectively assessing the multi-system nature of COPD could lead to improved prognostication and targeted therapy for patients.

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

RATIONALE: There is conflicting evidence whether aerobic exercise training (AET) reduces pulse wave velocity (PWV) in adults with and without long-term conditions (LTCs). OBJECTIVE: To explore whether PWV improves with AET in adults with and without LTC, to quantify the magnitude of any effect and understand the influence of the exercise prescription. DATA SOURCES: CENTRAL, MEDLINE and EMBASE were among the databases searched. ELIGIBILITY CRITERIA: We included studies with a PWV measurement before and after supervised AET of at least 3 weeks duration. Exclusion criteria included resistance exercise and alternative measures of arterial stiffness. DESIGN: Controlled trials were included in a random effects meta-analysis to explore the effect of AET on PWV. Uncontrolled studies were included in a secondary meta-analysis and meta-regression exploring the effect of patient and programme factors on change in PWV. The relevant risk of bias tool was used for each study design. RESULTS: 79 studies (n=3729) were included: 35 controlled studies (21 randomised control trials (RCT) (n=1240) and 12 non-RCT (n=463)) and 44 uncontrolled (n=2026). In the controlled meta- analysis, PWV was significantly reduced following AET (mean (SD) 11 (7) weeks) in adults with and without LTC (mean difference -0.63; 95% CI -0.82 to -0.44; p<0.0001). PWV was similarly reduced between adults with and without LTC (p<0.001). Age, but not specific programme factors, was inversely associated with a reduction in PWV -0.010 (-0.020 to -0.010) m/s, p<0.001. DISCUSSION: Short-term AET similarly reduces PWV in adults with and without LTC. Whether this effect is sustained and the clinical implications require further investigation.

The role of diet and nutrition in the management of COPD.

In 2014, the European Respiratory Society published a statement on nutritional assessment and therapy in COPD. Since then, increasing research has been performed on the role of diet and nutrition in the prevention and management of COPD. Here, we provide an overview of recent scientific advances and clinical implications. Evidence for a potential role of diet and nutrition as a risk factor in the development of COPD has been accumulating and is reflected in the dietary patterns of patients with COPD. Consuming a healthy diet should, therefore, be promoted in patients with COPD. Distinct COPD phenotypes have been identified incorporating nutritional status, ranging from cachexia and frailty to obesity. The importance of body composition assessment and the need for tailored nutritional screening instruments is further highlighted. Dietary interventions and targeted single or multi-nutrient supplementation can be beneficial when optimal timing is considered. The therapeutic window of opportunity for nutritional interventions during and recovering from an acute exacerbation and hospitalisation is underexplored.

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

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

Diagnostic delays for breathlessness in primary care: a qualitative study to investigate current care and inform future pathways.

BACKGROUND: Evidence about the delays to diagnosis for patients presenting with breathlessness is lacking. AIM: To explore current care of patients with breathlessness through the experiences of adults presenting with chronic breathlessness who are awaiting a diagnosis and the experiences of primary care clinicians. DESIGN AND SETTING: Qualitative study with adults presenting with chronic breathlessness and clinicians across 10 general practices. METHOD: Semi-structured interviews were conducted with patients and clinicians. Participants were recruited from a feasibility cluster randomised controlled trial investigating a structured diagnostic pathway for breathlessness. An interview guide explored experiences of help seeking for breathlessness, the diagnostic process, and associated health care. Transcripts were analysed using thematic analysis supported by NVivo software. RESULTS: Interviews were conducted with 34 patients (mean age 68 years, standard deviation [SD] 10.8, of whom 20 were female [59%]) and 10 clinicians (mean 17 years of experience, SD 6.3, of whom five were female [50%]). Five themes were identified: recognising and validating symptoms of breathlessness is an important first step; clinical decision making for breathlessness is complex; difficult conversations arise when a disease-related diagnosis is not confirmed; disease management rather than symptom management is prioritised by clinicians; and patient experience is influenced by clinician communication style. CONCLUSION: The findings indicate potential explanations for delays to diagnosis for patients with chronic breathlessness. Interventions are needed to enhance symptom recognition, include alternative approaches to incremental investigation, and expand the concept of diagnosis beyond a disease label to improve communication, with the ultimate aim of earlier diagnosis and management to improve patient outcomes.

Collaboration between explainable artificial intelligence and pulmonologists improves the accuracy of pulmonary function test interpretation.

BACKGROUND: Few studies have investigated the collaborative potential between artificial intelligence (AI) and pulmonologists for diagnosing pulmonary disease. We hypothesised that the collaboration between a pulmonologist and AI with explanations (explainable AI (XAI)) is superior in diagnostic interpretation of pulmonary function tests (PFTs) than the pulmonologist without support. METHODS: The study was conducted in two phases, a monocentre study (phase 1) and a multicentre intervention study (phase 2). Each phase utilised two different sets of 24 PFT reports of patients with a clinically validated gold standard diagnosis. Each PFT was interpreted without (control) and with XAI's suggestions (intervention). Pulmonologists provided a differential diagnosis consisting of a preferential diagnosis and optionally up to three additional diagnoses. The primary end-point compared accuracy of preferential and additional diagnoses between control and intervention. Secondary end-points were the number of diagnoses in differential diagnosis, diagnostic confidence and inter-rater agreement. We also analysed how XAI influenced pulmonologists' decisions. RESULTS: In phase 1 (n=16 pulmonologists), mean preferential and differential diagnostic accuracy significantly increased by 10.4% and 9.4%, respectively, between control and intervention (p<0.001). Improvements were somewhat lower but highly significant (p<0.0001) in phase 2 (5.4% and 8.7%, respectively; n=62 pulmonologists). In both phases, the number of diagnoses in the differential diagnosis did not reduce, but diagnostic confidence and inter-rater agreement significantly increased during intervention. Pulmonologists updated their decisions with XAI's feedback and consistently improved their baseline performance if AI provided correct predictions. CONCLUSION: A collaboration between a pulmonologist and XAI is better at interpreting PFTs than individual pulmonologists reading without XAI support or XAI alone.

Lung volume reduction surgery versus endobronchial valves: a randomised controlled trial.

BACKGROUND: Lung volume reduction surgery (LVRS) and bronchoscopic lung volume reduction (BLVR) with endobronchial valves can improve outcomes in appropriately selected patients with emphysema. However, no direct comparison data exist to inform clinical decision making in people who appear suitable for both procedures. Our aim was to investigate whether LVRS produces superior health outcomes when compared with BLVR at 12 months. METHODS: This multicentre, single-blind, parallel-group trial randomised patients from five UK hospitals, who were suitable for a targeted lung volume reduction procedure, to either LVRS or BLVR and compared outcomes at 1 year using the i-BODE score. This composite disease severity measure includes body mass index, airflow obstruction, dyspnoea and exercise capacity (incremental shuttle walk test). The researchers responsible for collecting outcomes were masked to treatment allocation. All outcomes were assessed in the intention-to-treat population. RESULTS: 88 participants (48% female, mean±sd age 64.6±7.7 years, forced expiratory volume in 1 s percent predicted 31.0±7.9%) were recruited at five specialist centres across the UK and randomised to either LVRS (n=41) or BLVR (n=47). At 12 months follow-up, the complete i-BODE was available in 49 participants (21 LVRS/28 BLVR). Neither improvement in the i-BODE score (LVRS -1.10±1.44 versus BLVR -0.82±1.61; p=0.54) nor in its individual components differed between groups. Both treatments produced similar improvements in gas trapping (residual volume percent predicted: LVRS -36.1% (95% CI -54.6- -10%) versus BLVR -30.1% (95% CI -53.7- -9%); p=0.81). There was one death in each treatment arm. CONCLUSION: Our findings do not support the hypothesis that LVRS is a substantially superior treatment to BLVR in individuals who are suitable for both treatments.

COPD: Providing the right treatment for the right patient at the right time.

Chronic Obstructive Pulmonary Disease (COPD) is a common disease associated with significant morbidity and mortality that is both preventable and treatable. However, a major challenge in recognizing, preventing, and treating COPD is understanding its complexity. While COPD has historically been characterized as a disease defined by airflow limitation, we now understand it as a multi-component disease with many clinical phenotypes, systemic manifestations, and associated co-morbidities. Evidence is rapidly emerging in our understanding of the many factors that contribute to the pathogenesis of COPD and the identification of "early" or "pre-COPD" which should provide exciting opportunities for early treatment and disease modification. In addition to breakthroughs in our understanding of the origins of COPD, we are optimizing treatment strategies and delivery of care that are showing impressive benefits in patient-centered outcomes and healthcare utilization. This special issue of Respiratory Medicine, "COPD: Providing the Right Treatment for the Right Patient at the Right Time" is a summary of the proceedings of a conference held in Stresa, Italy in April 2022 that brought together international experts to discuss emerging evidence in COPD and Pulmonary Rehabilitation in honor of a distinguished friend and colleague, Claudio Ferdinando Donor (1948-2021). Claudio was a true pioneer in the field of pulmonary rehabilitation and the comprehensive care of individuals with COPD. He held numerous leadership roles in in the field, provide editorial stewardship of several respiratory journals, authored numerous papers, statement and guidelines in COPD and Pulmonary Rehabilitation, and provided mentorship to many in our field. Claudio's most impressive talent was his ability to organize spectacular conferences and symposia that highlighted cutting edge science and clinical medicine. It is in this spirit that this conference was conceived and planned. These proceedings are divided into 4 sections which highlight crucial areas in the field of COPD: (1) New concepts in COPD pathogenesis; (2) Enhancing outcomes in COPD; (3) Non-pharmacologic management of COPD; and (4) Optimizing delivery of care for COPD. These presentations summarize the newest evidence in the field and capture lively discussion on the exciting future of treating this prevalent and impactful disease. We thank each of the authors for their participation and applaud their efforts toward pushing the envelope in our understanding of COPD and optimizing care for these patients. We believe that this edition is a most fitting tribute to a dear colleague and friend and will prove useful to students, clinicians, and researchers as they continually strive to provide the right treatment for the right patient at the right time. It has been our pleasure and a distinct honor to serve as editors and oversee such wonderful scholarly work.

Exercise rehabilitation in COPD and heart failure: comparison of two national audits.

Background: Pulmonary (PR) and cardiac rehabilitation (CR) are recommended in the management of chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF); the impact of coexisting COPD and CHF on completion and outcomes of rehabilitation programmes is unknown. We examined enrolment, completion and clinical outcomes of CR and PR in adults with COPD, CHF and coexisting COPD and CHF. Methods: The National Audit of CR and National COPD Audit Programme: clinical audits of PR were analysed (211 PR and 237 CR programmes); adults with a diagnosis of CHF, COPD or coexisting COPD and CHF were identified (COPD+CHF or CHF+COPD according to database). Propensity matching was conducted (age, sex, body mass index and functional status) between COPD+CHF and COPD, and CHF+COPD and CHF. Group by time interaction was examined using mixed 2×2 analysis of variance. Results: Those with CHF+COPD had lower enrolment and completion of CR compared to those with CHF; there were no differences in PR enrolment or completion between the two groups. Adults with COPD made a significantly larger gain in the incremental shuttle walk test compared to adults with COPD+CHF following PR (59.3 m versus 37.4 m); the improvements following CR were similar (CHF 77.3 m versus CHF+COPD 58.3 m). Similar improvements were made in the 6-min walk test following CR (CHF 45.1 m versus CHF+COPD 38.8 m) and PR (COPD 48.2 m versus COPD+CHF 44.0 m). Comparable improvements in quality of life and mood state were made following CR and PR, regardless of diagnosis. Conclusion: We have demonstrated that multi-morbid adults benefit from exercise-based rehabilitation, yet efforts are needed to promote completion. These findings support group-based, tailored, multi-morbid exercise rehabilitation.

Body mass index across adulthood and the development of airflow obstruction and emphysema.

BACKGROUND: Low body mass index (BMI) is associated with COPD, but temporal relationships between airflow obstruction (AO) development and emphysematous change are unclear. We investigated longitudinal changes in BMI, AO, and lung density throughout adulthood using data from the Framingham Offspring Cohort (FOC). METHODS: BMI trajectories were modelled throughout adulthood in 4587 FOC participants from Exam 2 (mean age = 44), through Exam 9 (mean age = 71), in AO participants and non-AO participants (AO n = 1036), determined by spirometry, using fractional polynomial growth curves. This process was repeated for low lung density (LLD) and non LLD participants (LLD n = 225) determined by Computed Tomography. Spirometry decline was compared separately between tertiles of BMI in those aged <40 years and associations between fat and lean mass (measured using Dual Energy X-ray Absorptiometry, DEXA) and development of AO and LLD were also assessed. Additional analyses were performed with adjustment for smoking volume. RESULTS: The BMI trajectory from 30 years of age was visually lower in the AO group than both non-AO smokers (non-

Comparing research recruitment strategies to prospectively identify patients presenting with breathlessness in primary care.

Two recruitment strategies for research were compared to prospectively identify patients with breathlessness who are awaiting a diagnosis in primary care. The first method utilised searches of the electronic patient record (EPR), the second method involved an electronic template triggered during a consultation. Using an electronic template triggered at the point of consultation increased recruitment to prospective research approximately nine-fold compared with searching for symptom codes and study mailouts.

A More Intense Examination of the Intensity of Physical Activity in People Living with Chronic Obstructive Pulmonary Disease: Insights from Threshold-Free Markers of Activity Intensity.

Physical activity (PA) intensity of people living with chronic obstructive pulmonary disease (COPD) is typically evaluated using intensity thresholds developed in younger, healthier populations with greater exercise capacity and free from respiratory symptoms. This study therefore compared (i) PA differences between COPD and non-COPD controls using both traditional intensity thresholds and threshold-free metrics that represent the volume and intensity of the whole PA profile, and (ii) explored the influence of exercise capacity on observed differences. Moderate-to-vigorous physical activity (MVPA), average acceleration (proxy for volume, mg) and intensity distribution of activity were calculated for 76 individuals with COPD and 154 non-COPD controls from wrist-worn ActiGraph accelerometry. PA profiles representing the minimum intensity (acceleration, mg) during the most active accumulated 5-960 min were plotted. Estimated VO2peak and relative intensity were derived from the incremental shuttle walk test distance. Compared to the non-COPD control group, individuals with COPD recorded fewer MVPA minutes (59 vs. 83 min/day), lower overall waking activity (29.1 vs. 36.4 mg) and a poorer waking intensity distribution (-2.73 vs. -2.57). Individuals with COPD also recorded a lower absolute intensity (acceleration, mg) for their most active 5-960 min, but higher intensity relative to their estimated exercise capacity derived from the ISWT. People with COPD have a lower volume and absolute intensity of PA than controls but perform PA at a higher relative intensity. There is a need to move away from absolute intensity thresholds, and towards personalised or relative-intensity thresholds, to reflect reduced exercise capacity in COPD populations.

Mortality associated with metabolic syndrome in people with COPD managed in primary care.

Objective: The prevalence of metabolic syndrome (MetS) has been reported to be higher in selected populations of people with COPD. The impact of MetS on mortality in COPD is unknown. We used routinely collected healthcare data to estimate the prevalence of MetS in people with COPD managed in primary care and determine its impact on 5-year mortality. Methods: Records from 103 955 patients with COPD from the Clinical Practice Research Datalink (CPRD-GOLD) between 2009 to 2017 were scrutinised. MetS was defined as the presence of three or more of: obesity, hypertension, lowered high-density lipoprotein cholesterol, elevated triglycerides or type 2 diabetes mellitus (T2DM). Univariate and multivariable Cox regression models were constructed to determine the prognostic impact of MetS on 5-year mortality. Similar univariate models were constructed for individual components of the definition of MetS. Results: The prevalence of MetS in the COPD cohort was 10.1%. Univariate analyses showed the presence of MetS increased mortality (hazard ratio (HR) 1.19, 95% CI: 1.12-1.27, p<0.001), but this risk was substantially attenuated in the multivariable analysis (HR 1.06, 95% CI: 0.99-1.13, p=0.085). The presence of hypertension (HR 1.70, 95% CI: 1.63-1.77, p<0.001) and T2DM (HR 1.41, 95% CI: 1.34-1.48, p<0.001) increased and obesity (HR 0.74, 95% CI: 0.71-0.78, p<0.001) reduced mortality risk. Conclusion: MetS in patients with COPD is associated with higher 5-year mortality, but this impact was minimal when adjusted for indices of COPD disease severity and other comorbidities. Individual components of the MetS definition exerted differential impacts on mortality suggesting limitation to the use of MetS as a multicomponent condition in predicting outcome in COPD.

Developing Appropriate Pulmonary Rehabilitation Services in Sri Lanka: Assessment of People Living with COPD and Healthcare Providers in Urban and Semi Urban Areas in Sri Lanka.

Introduction: Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, corresponding to 5% of all deaths globally, with more than 90% occurring in low- and middle-income countries (LMIC). Pulmonary Rehabilitation (PR) is a routine clinical service for COPD management, often used in western countries. At present, there is no formal PR in Sri Lanka; a culturally appropriate programme is required that considers the views of adults living with COPD and healthcare providers (HCPs) who would be involved in the referral or delivery of PR. Purpose: The study assessed the attitudes and preferences of Sri Lankan adults living with COPD and attitudes and barriers of HCPs making PR referrals to inform an appropriate PR programme. Methodology: A descriptive cross-sectional study was conducted with the ethical clearance of Colombo south teaching hospital ERC committee (ERC Application No. 674), among adults living with COPD and HCPs in Colombo district, Sri Lanka. Adults living with COPD were enrolled August 2018-December 2018 using systematic random sampling from Colombo South Teaching Hospital and were assessed using a pre-tested interviewer administered questionnaire. HCPs were recruited from Colombo South Teaching Hospital and Jaffna Teaching Hospital between August 2018 and November 2018 and assessed using self-administered questionnaire. Results: Responses from 138 adults living with COPD (53% male, 52% aged ≥60 years) and 277 HCPs were collected. The majority of adults living with COPD were interested in participating in PR (80%) and would prefer PR to be delivered in a supervised, group-based, setting with hospital-based (49%). Adults living with COPD were mostly (73%) willing to spend between 30 minutes and 2 hours per day for PR-related activities. Among HCPs, 234 (83%) were nurses, 29 (11%) were hospital doctors and 14 (4%) were family physicians. The majority of HCPs stated that they were unsure about referring adults with COPD for PR (86%) and 61% stated considerable uncertainty regarding the availability of resources for PR. Nearly half of the HCPs (45%) felt they were not adequately prepared to refer adults living with COPD to PR programmes. Most HCPs (92%) reported that PR is worthwhile for COPD management. Conclusion: Adults living with COPD in Sri Lanka are willing to attend PR and would prefer group-based programmes delivered in hospitals, under the supervision of qualified personnel. Awareness about PR is poor and there is a lack of readiness to refer to PR amongst HCPs. There is an urgent need to train HCPs on PR and develop effective referral strategies to support PR uptake and delivery for adults living with COPD in Sri Lanka.

A proof of concept for continuous, non-invasive, free-living vital signs monitoring to predict readmission following an acute exacerbation of COPD: a prospective cohort study.

BACKGROUND: The use of vital signs monitoring in the early recognition of an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) post-hospital discharge is limited. This study investigated whether continuous vital signs monitoring could predict an AECOPD and readmission. METHODS: 35 people were recruited at discharge following hospitalisation for an AECOPD. Participants were asked to wear an Equivital LifeMonitor during waking hours for 6 weeks and to complete the Exacerbations of Chronic Pulmonary Disease Tool (EXACT), a 14-item symptom diary, daily. The Equivital LifeMonitor recorded respiratory rate (RR), heart rate (HR), skin temperature (ST) and physical activity (PA) every 15-s. An AECOPD was classified as mild (by EXACT score), moderate (prescribed oral steroids/antibiotics) or severe (hospitalisation). RESULTS: Over the 6-week period, 31 participants provided vital signs and symptom data and 14 participants experienced an exacerbation, of which, 11 had sufficient data to predict an AECOPD. HR and PA were associated with EXACT score (p < 0.001). Three days prior to an exacerbation, RR increased by mean ± SD 2.0 ± 0.2 breaths/min for seven out of 11 exacerbations and HR increased by 8.1 ± 0.7 bpm for nine of these 11 exacerbations. CONCLUSIONS: Increased heart rate and reduced physical activity were associated with worsening symptoms. Even with high-resolution data, the variation in vital signs data remains a challenge for predicting AECOPDs. Respiratory rate and heart rate should be further explored as potential predictors of an impending AECOPD. TRIAL REGISTRATION: ISRCTN registry; ISRCTN12855961. Registered 07 November 2018-Retrospectively registered, https://www.isrctn.com/ISRCTN12855961.

Culturally adapted pulmonary rehabilitation for adults living with post-tuberculosis lung disease in Kyrgyzstan: protocol for a randomised controlled trial with blinded outcome measures.

INTRODUCTION: Pulmonary rehabilitation (PR) is a programme of individually prescribed physical exercise, education and self-management activities. PR is recommended in international guidelines for managing chronic obstructive pulmonary disease (COPD) and other chronic respiratory diseases. PR is still under-recognised in tuberculosis (TB) guidelines and PR is not available in many low and middle-income countries and for people with post-TB lung disease (PTBLD). The main aims of the study are to adapt and define a culturally appropriate PR programme in Kyrgyzstan for people living with PTBLD and to test, in a fully powered randomised controlled trial (RCT), the effectiveness of PR in improving exercise capacity for people living with PTBLD. METHODS AND ANALYSIS: The study will be divided into three stages: stage 1: focus group discussions with patients living with PTBLD and interviews with PR referrers will be conducted to explore initial perceptions and inform the cultural adaptation, structure and content of PR. Stage 2a: a single-blind RCT evaluating the effectiveness of a culturally adapted 6-week PR programme on maximal exercise capacity, assessed by the incremental shuttle walking test, before and after PR. Participants will be additionally followed-up 12 weeks postbaseline. Additional outcomes will include health-related quality of life, respiratory symptoms, psychological well-being and physical function. Stage 2b: participants' experience of PR will be collected through interviews and using a log book and a patient evaluation form. Staff delivering PR will be interviewed to explore their experience of delivering the intervention and refining the delivery for future implementation. ETHICS AND DISSEMINATION: The study was approved 22/07/2019 by Ethics Committee National Center for Cardiology and Internal Medicine (reference number 17) and by University of Leicester ethics committee (reference number 22293). Study results will be disseminated through appropriate peer-reviewed journals, national and international respiratory/physiotherapy conferences, social media, and through patient and public involvement events in Kyrgyzstan and in the UK. TRIAL REGISTRATION NUMBER: ISRCTN11122503.

Usability of Wearable Multiparameter Technology to Continuously Monitor Free-Living Vital Signs in People Living With Chronic Obstructive Pulmonary Disease: Prospective Observational Study.

BACKGROUND: Vital signs monitoring (VSM) is routine for inpatients, but monitoring during free-living conditions is largely untested in chronic obstructive pulmonary disease (COPD). OBJECTIVE: This study investigated the usability and acceptability of continuous VSM for people with COPD using wearable multiparameter technology. METHODS: In total, 50 people following hospitalization for an acute exacerbation of COPD (AECOPD) and 50 people with stable COPD symptoms were asked to wear an Equivital LifeMonitor during waking hours for 6 weeks (42 days). The device recorded heart rate (HR), respiratory rate (RR), skin temperature, and physical activity. Adherence was defined by the number of days the vest was worn and daily wear time. Signal quality was examined, with thresholds of ≥85% for HR and ≥80% for RR, based on the device's proprietary confidence algorithm. Data quality was calculated as the percentage of wear time with acceptable signal quality. Participant feedback was assessed during follow-up phone calls. RESULTS: In total, 84% of participants provided data, with average daily wear time of 11.8 (SD 2.2) hours for 32 (SD 11) days (average of study duration 76%, SD 26%). There was greater adherence in the stable group than in the post-AECOPD group (≥5 weeks wear: 71.4% vs 45.7%; P=.02). For all 84 participants, the median HR signal quality was 90% (IQR 80%-94%) and the median RR signal quality was 93% (IQR 92%-95%). The median HR data quality was 81% (IQR 58%-91%), and the median RR data quality was 85% (IQR 77%-91%). Stable group BMI was associated with HR signal quality (rs=0.45, P=.008) and HR data quality (rs=0.44, P=.008). For the AECOPD group, RR data quality was associated with waist circumference and BMI (rs=-0.49, P=.009; rs=-0.44, P=.02). In total, 36 (74%) participants in the Stable group and 21 (60%) participants in the AECOPD group accepted the technology, but 10 participants (12%) expressed concerns with wearing a device around their chest. CONCLUSIONS: This wearable multiparametric technology showed good user acceptance and was able to measure vital signs in a COPD population. Data quality was generally high but was influenced by body composition. Overall, it was feasible to continuously measure vital signs during free-living conditions in people with COPD symptoms but with additional challenges in the post-AECOPD context.

Whole-body and muscle responses to aerobic exercise training and withdrawal in ageing and COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) patients exhibit lower peak oxygen uptake (V'O2 peak), altered muscle metabolism and impaired exercise tolerance compared with age-matched controls. Whether these traits reflect muscle-level deconditioning (impacted by ventilatory constraints) and/or dysfunction in mitochondrial ATP production capacity is debated. By studying aerobic exercise training (AET) at a matched relative intensity and subsequent exercise withdrawal period we aimed to elucidate the whole-body and muscle mitochondrial responsiveness of healthy young (HY), healthy older (HO) and COPD volunteers to whole-body exercise. METHODS: HY (n=10), HO (n=10) and COPD (n=20) volunteers were studied before and after 8 weeks of AET (65% V'O2 peak) and after 4 weeks of exercise withdrawal. V'O2 peak, muscle maximal mitochondrial ATP production rate (MAPR), mitochondrial content, mitochondrial DNA (mtDNA) copy number and abundance of 59 targeted fuel metabolism mRNAs were determined at all time-points. RESULTS: Muscle MAPR (normalised for mitochondrial content) was not different for any substrate combination in HO, HY and COPD at baseline, but mtDNA copy number relative to a nuclear-encoded housekeeping gene (mean±sd) was greater in HY (804±67) than in HO (631±69; p=0.041). AET increased V'O2 peak in HO (17%; p=0.002) and HY (21%; p<0.001), but not COPD (p=0.603). Muscle MAPR for palmitate increased with training in HO (57%; p=0.041) and HY (56%; p=0.003), and decreased with exercise withdrawal in HO (-45%; p=0.036) and HY (-30%; p=0.016), but was unchanged in COPD (p=0.594). mtDNA copy number increased with AET in HY (66%; p=0.001), but not HO (p=0.081) or COPD (p=0.132). The observed changes in muscle mRNA abundance were similar in all groups after AET and exercise withdrawal. CONCLUSIONS: Intrinsic mitochondrial function was not impaired by ageing or COPD in the untrained state. Whole-body and muscle mitochondrial responses to AET were robust in HY, evident in HO, but deficient in COPD. All groups showed robust muscle mRNA responses. Higher relative exercise intensities during whole-body training may be needed to maximise whole-body and muscle mitochondrial adaptation in COPD.