Physical activity in patients with COPD

Reliability of 24-h measurement of physical activity, sleep, and sedentary time in adult patients with asthma using a triaxial accelerometer

OBJECTIVE

Physical activity (PA), sleep, and sedentary time (SST) are important outcomes to monitor and to improve as part of patients' asthma management. This study aimed to assess the number of measurement days needed to reliably measure PA and SST. Secondly, the influence of external factors on the reliability of measuring PA and SST was studied.

METHODS

Adult patients with stable asthma were asked to wear a triaxial accelerometer for at least four days, with at least 22.5 h of wear time per day. The Intraclass Correlation Coefficients (ICCs) between different number of measurement days were used to determine reliability. Values ≥0.75 indicated good reliability.

RESULTS

Data from 452 patients were analyzed (63% women; age: 49 ± 16 years; FEV1: 87 ± 17% predicted). PA could reliably be measured with four valid measurement days (ICC 0.761). For SST, three days were needed (ICC 0.778). In summer and autumn, three days were needed to reliably measure PA, in winter four, in spring six. For SST, five days were needed in spring for good reliability, and two in all other seasons.

CONCLUSION

Based on data from four valid days, PA and SST can reliably be measured with an accelerometer in patients with asthma. Seasonal influences are present, especially during spring. When measuring for four days, using only weekdays or three weekdays and one weekend day is recommended. The degree of asthma control, dyspnea or spirometric values did not influence the reliability.

Comparison of the muscle oxygenation during submaximal and maximal exercise tests in patients post-coronavirus disease 2019 syndrome with pulmonary involvement

INTRODUCTION

Pulmonary involvement is prevalent in patients with coronavirus disease 2019 (COVID-19). Arterial hypoxemia may reduce oxygen transferred to the skeletal muscles, possibly leading to impaired exercise capacity. Oxygen uptake may vary depending on the increased oxygen demand of the muscles during submaximal and maximal exercise.

OBJECTIVE

This study aimed to compare muscle oxygenation during submaximal and maximal exercise tests in patients with post-COVID-19 syndrome with pulmonary involvement.

METHODS

Thirty-nine patients were included. Pulmonary function (spirometry), peripheral muscle strength (dynamometer), quadriceps femoris (QF) muscle oxygenation (Moxy® device), and submaximal exercise capacity (six-minute walk test (6-MWT)) were tested on the first day, maximal exercise capacity (cardiopulmonary exercise test (CPET)) was tested on the second day. Physical activity level was evaluated using an activity monitor worn for five consecutive days. Cardiopulmonary responses and muscle oxygenation were compared during 6-MWT and CPET.

RESULTS

Patients' minimum and recovery muscle oxygen saturation were significantly decreased; maximum total hemoglobin increased, heart rate, blood pressure, breathing frequency, dyspnea, fatigue, and leg fatigue at the end-of-test and recovery increased in CPET compared to 6-MWT (p < .050). Peak oxygen consumption (VO2peak) was 18.15 ± 4.75 ml/min/kg, VO2peak; percent predicted < 80% was measured in 51.28% patients. Six-MWT distance and QF muscle strength were less than 80% predicted in 58.9% and 76.9% patients, respectively.

CONCLUSIONS

In patients with post-COVID-19 syndrome with pulmonary involvement, muscle deoxygenation of QF is greater during maximal exercise than during submaximal exercise. Specifically, patients with lung impairment should be evaluated for deoxygenation and should be taken into consideration during pulmonary rehabilitation.

Effect of physical activity in lymphocytes senescence burden in patients with COPD

Chronic obstructive pulmonary disease (COPD) is regarded as an accelerated-age disease in which chronic inflammation, maladaptive immune responses, and senescence cell burden coexist. Accordingly, cellular senescence has emerged as a potential mechanism involved in COPD pathophysiology. In this study, 25 stable patients with COPD underwent a daily physical activity promotion program for 6 mo. We reported that increase of physical activity was related to a reduction of the senescent cell burden in circulating lymphocytes of patients with COPD. Senescent T-lymphocyte population, characterized by absence of surface expression of CD28, was reduced after physical activity intervention, and the reduction was associated to the increase of physical activity level. In addition, the mRNA expression of cyclin-dependent kinase inhibitors, a hallmark of cell senescence, was reduced and, in accordance, the proliferative capacity of lymphocytes was improved postintervention. Moreover, we observed an increase in functionality in T cells from patients after intervention, including improved markers of activation, enhanced cytotoxicity, and altered cytokine secretions in response to viral challenge. Lastly, physical activity intervention reduced the potential of lymphocytes' secretome to induce senescence in human primary fibroblasts. In conclusion, our study provides, for the first time, evidence of the potential of physical activity intervention in patients with COPD to reduce the senescent burden in circulating immune cells.NEW & NOTEWORTHY For the first time, we identified in patients with COPD a relation between physical activity intervention with respiratory function improvement and cellular senescence burden in lymphocytes that improved the T cell functionality and proliferative capacity of patients. In addition, our experiments highlight the possible impact of T-cell senescence in other cell types which could be related to some of the clinical lung complications observed in COPD.

Processing of Sedentary Time and Its Reference Equation in Patients with COPD

Purpose

Sedentary time (ST) is associated with mortality independent of moderate-to-vigorous physical activity in patients with COPD. The proper processing methods for the measurement data and factors related to ST are still unknown. We investigated several conditions for determining the proper processing of ST accelerometric data and created a reference equation for ST using ST-related factors.

Patients and Methods

In Study 1, we evaluated the minimum required number of days to obtain repeatability at different measurement times and assessed the effects of rainy days or weekend days on ST in patients with COPD. In Study 2, we detected the ST-related factors among 28 parameters and created a reference equation for ST using the detected factors.

Results

In Study 1, 38 patients with stable COPD were analyzed. The minimum number of days required for repeatability was 3 for 8-h wearing and 2 for 10-h wearing. The ST was significantly prolonged on rainy days, but not on weekends. In Study 2, 216 patients with stable COPD were analyzed. BMI, FEV1%pred, 6MWD, and mMRC were detected as ST-related factors, and a reference equation could be created using these four factors. The equation was validated for patients whose ST was ≥ 6 h.

Conclusion

By using properly processed measurement data of ST, we created a reference equation for assessing ST that is expected to be useful for providing individual guidance on the shortening of ST to patients with COPD.

Exploring the impact of the environment on physical activity in patients with chronic obstructive pulmonary disease (EPCOT)-A comparative analysis between suggested and free walking: Protocol study

BACKGROUND

Individuals with chronic obstructive pulmonary disease (COPD) exhibit reduced levels of physical activity, which are associated with poorer outcomes. The number of clinical trials aiming to promote behavioral changes to increase physical activity in this population has grown; therefore, these trials have yet to produce satisfactory results. An ecological model encompassing individual, social, environmental, and political factors represent a potentially more effective approach to promoting physical activity. While favorable urban environments can positively impact physical activity, specifically tailored environmental interventions for individuals with COPD could enhance their engagement in physical activity. Therefore, the aim of this randomized controlled trial (RCT) study was to analyze the effects of walking in a suggested environment and free walking on physical activity levels in individuals with COPD.

METHODS

The environment on physical activity for chronic obstructive disease (EPCOT) is a randomized controlled clinical trial protocol approved by our institution's Ethics Committee and registered with The Brazilian Registry of Clinical Trials (ReBEC) (https://ensaiosclinicos.gov.br, number RBR-4tfwdhp). This protocol will involve 38 volunteers diagnosed with COPD recruited from the pulmonary physiotherapy and rehabilitation service. The volunteers were randomly divided into two walking groups: an experimental group (ERG) with guidance for walking in a suggested environment and an active control group (ACG) instructed to choose their own routes. The intervention consisted of eight consecutive weeks, with progressive walks carried out 3 to 5 times weekly. The primary outcome will be assessing participants' physical activity levels. Secondary outcomes will include exercise capacity, quality of life, dyspnea levels, motivation, anxiety, depression, and perceptions of the environment. All assessments will occur before and after the intervention period, aiming to fill a literature gap by investigating the impact of urban environments on COPD-related physical activity. The results may shed light on the importance of environmental factors in promoting physical activity among individuals with COPD, helping to develop more effective interventions.

Functional capacity using sit-to-stand tests in people with chronic obstructive pulmonary disease and its relationship with disease severity-a cross-sectional study with matched controls

BACKGROUND

Functional capacity impairment is a crucial consequence of chronic obstructive pulmonary disease (COPD). Although it can be identified with simple tests, such as the sit-to-stand tests, its prevalence, relation with disease severity, and the characteristics of people presenting this impairment remain unknown.

OBJECTIVE

To explore the functional capacity of people with COPD.

METHODS

A cross-sectional study with people with COPD and age-/sex-matched healthy controls was conducted. Functional capacity was assessed with the 5-repetitions (5-STS) and the 1-minute (1-minSTS) sit-to-stand tests. People with COPD were grouped according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classifications. Comparisons between people with COPD and healthy controls, and among GOLD groups were established. Associations between symptoms, muscle strength, quality of life, and measures of functional capacity were explored.

RESULTS

302 people with COPD [79% male; mean (SD) 68 (10) years old] and 304 healthy controls [75% male; 66 (9) years old] were included. 23% of people with COPD presented impairment in the 5-STS and 33% in the 1-minSTS. People with COPD from all GOLD classifications presented significantly lower functional capacity than healthy controls (5-STS: COPD median [1st quartile; 3rd quartile] 8.4 [6.7; 10.6] versus healthy 7.4 [6.2; 9.3] s; 1-minSTS: COPD 27 [21; 35] vs healthy 35 [29; 43] reps). Correlations with symptoms, muscle strength, and quality of life were mostly weak (5-STS: rs [-0.34; 0.33]; 1-minSTS: rs [-0.47; 0.40]).

CONCLUSION

People with COPD have decreased functional capacity independently of their GOLD classifications. The prevalence of functional impairment is 23-33%. Because impaired functional capacity is a treatable trait not accurately reflected by other outcomes, comprehensive assessment and management is needed.

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.

Qualitative interviews of patients with COPD and muscle weakness enrolled in a clinical trial evaluating a new anabolic treatment: patient perspectives of disease experience, trial participation and outcome assessments

BACKGROUND

Chronic obstructive pulmonary disease (COPD) and muscle weakness can cause impaired physical function, significantly impacting patients' health-related quality of life (HRQoL). Loss of muscle strength is usually assessed through clinical and performance outcome (PerfO) assessments, which consists of tasks performed in a standardized manner, providing evidence of a patient's functional ability. However, evidence documenting the patient experience of COPD and muscle weakness is limited.

METHODS

This two-stage qualitative study used semi-structured interviews in patients aged 45-80 years with COPD (post-bronchodilator forced expiratory volume in 1s [FEV1]/forced vital capacity ratio < 0.70, and FEV1% predicted of 30-80%) and muscle weakness. In Stage 1, 30-minute concept elicitation interviews were conducted with participants recruited across three US sites to explore impacts on physical functioning and activities of daily living. In Stage 2, interviews were performed with participants exiting a Phase IIa trial investigating the efficacy of a selective androgen receptor modulator (GSK2881078) on leg strength, whereby PerfOs were used to evaluate strength and physical functioning endpoints. These participants completed either 60-minute in-depth (n = 32) or 15-minute confirmatory (n = 35) interviews exploring trial experience, completion of outcome measures, disease experience and treatment satisfaction.

RESULTS

In Stage 1 (n = 20), most participants described their muscles as weak (83.3%). Difficulties with walking (100%) and lifting heavy objects (90%) were reported. In Stage 2, 60-minute interviews, all participants (n = 32) reported a positive trial experience. Most participants reported that the home exercise program was easy to fit into daily life (77.8%), the PROactive daily diary was easy to complete (100%) and wearable sensors were easy to use (65.6%). However, technical issues were reported (71%), and few participants (19.4%) found physical assessments easy to complete. Improvements in muscle strength and functional limitations were reported by most participants. The shorter 15-minute confirmatory interviews (n = 35) supported the in-depth interview results.

CONCLUSION

The qualitative interviews generated in-depth evidence of key concepts relevant to patients with COPD and muscle weakness and support the assessments of patient strength and physical function as outcome measures in this population in future studies.

TRIAL NUMBER

GSK Stage 1: 206869; Stage 2: 200182, NCT03359473; Registered December 2, 2017, https://clinicaltrials.gov/ct2/show/NCT03359473 .

Efficacy of Digital Therapeutics for Pulmonary Rehabilitation: A Multi-Center, Randomized Controlled Trial

BACKGROUND

This study aimed to investigate the efficacy and safety of digital therapeutics (DTx), EASYBREATH, for pulmonary rehabilitation (PR) in patients with chronic respiratory diseases (CRDs).

MATERIALS AND METHODS

This prospective randomized controlled trial was conducted at multiple centers. Participants were randomly allocated 1:1 to the DTx group (DTxG), provided with DTx using EASYBREATH. The DTxG underwent an 8-week PR program with evaluations conducted at baseline, four weeks, and eight weeks. The control group (CG) underwent one PR session and was advised to exercise and undergo the same evaluation. The primary outcome was the change in six-minute walking distance (6MWD) over eight weeks, and secondary outcomes included changes in scores of Modified Medical Research Council (mMRC), chronic obstructive pulmonary disease assessment test (CAT), and St. George's respiratory questionnaire (SGRQ).

RESULTS

The change in 6MWD after eight weeks demonstrated a significant difference between the DTxG and CG (57.68 m vs. 21.71 m, p = 0.0008). The change in mMRC scores (p = 0.0008), CAT scores (p < 0.0001), and total SGRQ scores (p = 0.0003) also showed a significant difference between the groups after eight weeks.

CONCLUSIONS

EASYBREATH significantly improved exercise capacity, alleviated dyspnea, and enhanced the overall quality of life at eight weeks. EASYBREATH is a highly accessible, time-efficient, and effective treatment option for CRD with high compliance.

Rural disparities impact response to a web-based physical activity self-management intervention in COPD: A secondary analysis

PURPOSE

This secondary exploratory analysis examined rural-urban differences in response to a web-based physical activity self-management intervention for chronic obstructive pulmonary disease (COPD).

METHODS

Participants with COPD (N = 239 US Veterans) were randomized to either a multicomponent web-based intervention (goal setting, iterative feedback of daily step counts, motivational and educational information, and an online community forum) or waitlist-control for 4 months with a 12-month follow-up. General linear modeling estimated the impact of rural/urban status (using Rural-Urban Commuting Area [RUCA] codes) on (1) 4- and 12-month daily step-count change compared to waitlist-control, and (2) intervention engagement (weekly logons and participant feedback).

FINDINGS

Rural (n = 108) and urban (n = 131) participants' mean age was 66.7±8.8 years. Rural/urban status significantly moderated 4-month change in daily step counts between randomization groups (p = 0.041). Specifically, among urban participants, intervention participants improved by 1500 daily steps more than waitlist-control participants (p = 0.001). There was no difference among rural participants. In the intervention group, rural participants engaged less with the step-count graphs on the website than urban participants at 4 months (p = 0.019); this difference dissipated at 12 months. More frequent logons were associated with greater change in daily step counts (p = 0.004); this association was not moderated by rural/urban status.

CONCLUSIONS

The web-based intervention was effective for urban, but not rural, participants at 4 months. Rural participants were also less engaged at 4 months, which may explain differences in effectiveness. Technology-based interventions can help address urban-rural disparities in patients with COPD, but may also contribute to them unless resources are available to support engagement with the technology.

Prognostic value of the serum creatinine/cystatin C ratio in patients with chronic obstructive pulmonary disease

BACKGROUND

Sarcopenia, characterized by skeletal muscle atrophy and physical inactivity, is a manifestation of chronic obstructive pulmonary disease (COPD) and is associated with a poor prognosis. The serum creatinine (Cr)/cystatin C (CysC) ratio has been proposed as a marker of sarcopenia, given its correlation with total skeletal muscle mass, and as a prognostic indicator in COPD. This study aimed to evaluate the usefulness of the serum Cr/CysC ratio as a prognostic determinant in these patients.

METHODS

A total of 124 outpatients with COPD were enrolled in this study. Their serum Cr and CysC levels were measured. Survival time analyses were conducted to compare mortality rates between the low and high serum Cr/CysC ratio groups. Multivariate analysis was performed to investigate the association between various factors.

RESULTS

Using a serum Cr/CysC cut-off value of 0.885, the mortality rate (per 1000 person-years) for overall mortality was significantly higher in the low serum Cr/CysC ratio group (69.2 versus 28.6; hazard ratio, 2.47; 95% confidence interval, 1.06-5.79; p < 0.05). Similarly, the mortality rate due to respiratory disease was also higher (37.8 versus 8.2; hazard ratio, 4.68; 95% confidence interval, 1.05-20.9; p < 0.05). Multivariate Cox proportional hazards analysis revealed that serum Cr/CysC was an independent risk factor for respiratory disease mortality, regardless of age and airflow limitations.

CONCLUSIONS

The serum Cr/CysC ratio could be a valuable clinical parameter for identifying sarcopenia and severe airflow obstruction. The study findings highlight the utility of this ratio as a prognostic predictor in patients with COPD.

Influence of physical activity on the prognosis of COPD patients: the HADO.2 score - health, activity, dyspnoea and obstruction

Objective

The aim of this study was to create a prognostic instrument for COPD with a multidimensional perspective that includes physical activity (PA). The score also included health status, dyspnoea and forced expiratory volume in 1 s (HADO.2 score).

Methods

A prospective, observational, non-intervention study was carried out. Patients were recruited from the six outpatient clinics of the respiratory service of a single university hospital. The component variables of the HADO.2 score and BODE index were studied, and PA was measured using an accelerometer. The outcomes for the HADO.2 score were mortality and hospitalisations during follow-up and an exploration of the correlation with health-related quality of life at the moment of inclusion in the study.

Results

401 patients were included in the study and followed up for three years. The HADO.2 score showed good predictive capacity for mortality: C-index 0.79 (0.72-0.85). The C-index for hospitalisations was 0.72 (0.66-0.77) and the predictive ability for quality of life, as measured by R2, was 0.63 and 0.53 respectively for the Saint George's Respiratory Questionnaire and COPD Assessment Test.

Conclusions

There was no statistically significant difference between the mortality predictive capacity of the HADO.2 score and the BODE index. Adding PA to the original BODE index significantly improved the predictive capacity of the index. The HADO.2 score, which includes PA as a key variable, showed good predictive capacity for mortality and hospitalisations. There were no differences in the predictive capacity of the HADO.2 score and the BODE index.

Physical activity and outcomes in Japanese patients with chronic obstructive pulmonary disease: From the Ishinomaki COPD Network registry

BACKGROUND

Low physical activity levels are associated with an increased risk of exacerbations and all-cause mortality in patients with chronic obstructive pulmonary disease (COPD); however, evidence is limited in a population with a low frequency of exacerbations, such as the Japanese population. This study investigated the effects of physical activity on outcomes in Japanese patients with COPD.

METHODS

We conducted a prospective observational study in a cohort of Japanese patients with COPD between April 2018 and July 2020. Characteristics, frequency of exacerbations, and mortality were assessed during the 1-year follow-up period. Logistic regression analysis evaluated the relationship between physical activity and outcomes.

RESULTS

A total of 309 patients (294 males; median age, 75 years) with stable COPD were included, and 307 completed follow-up. Patients with lower levels of physical activity were older, and showed increased airflow obstruction, limited exercise capacity, increased dyspnea, depressive state, poor health status, muscle weakness, and more information needs for the disease. Patients with high levels of physical activity had a lower risk of exacerbation, including hospital admission, compared to those with low levels of activity (odds ratio [OR], 0.46; 95 % confidence interval [CI], 0.22-0.97; and OR, 0.21; 95 % CI, 0.09-0.50, respectively). High physical activity was associated with a reduced risk of all-cause mortality (OR, 0.07; 95 % CI, 0.01-0.55) and respiratory mortality (OR, 0.16; 95 % CI, 0.02-1.47).

CONCLUSIONS

These findings showed that higher physical activity is associated with better clinical outcomes, even in a COPD population with a low frequency of exacerbations.

The Relationship between Physical Activity, Depression and Anxiety in People with COPD: A Systematic Review and Meta-analyses

Depression and anxiety are related to physical activity among people with chronic obstructive pulmonary disease (COPD), although the strength and direction of the reported relationships are inconsistent. This study systematically synthesized the relationships between physical activity and i) depression and ii) anxiety in people with COPD. Physical activity measurement type (objective, self-report) was examined as a moderator of these relationships. A systematic search of physical activity and COPD was conducted from inception to February 2022 across 8 databases. Studies were included if they provided correlation coefficients for the relationship between measures of physical activity and depression or anxiety in people with COPD and were published in English. Two reviewers independently screened, reviewed and extracted data, with discrepancies resolved by a third reviewer. Across 13 studies, a small relationship was found between physical activity and depression, weighted r = -0.15, 95%CI [-0.21, -0.10], which was not moderated by physical activity measurement type. Across 8 studies, a negligible relationship was found between physical activity and anxiety, weighted r = -0.03, 95%CI [-0.11, 0.04], although this was moderated by physical activity measurement type, such that self-reported physical activity had a small negative relationship with anxiety (weighted r = -0.09, 95% CI [-0.15, -0.03]) and objectively measured physical activity had a small positive relationship (weighted r = 0.07, 95% CI [-0.13, 0.26]). In COPD, the bivariate association between physical activity and anxiety and depression are small.

Living with COPD: understanding patient experiences through the lens of photovoice

BACKGROUND

Conventional quantitative or qualitative methodologies may not encompass the wide array of experiences of individuals living with Chronic Obstructive Pulmonary Disease (COPD). We used a novel approach - photovoice-to understand the impact of COPD on activities of daily living (ADLs) in a multicultural Asian country.

METHODS

We recruited a purposive sample of eight patients from the outpatient clinics of the National University Health System, Singapore, between December 2020 and August 2021. We adopted a photovoice approach for data collection; participants were invited to take photos of how ADLs were impacted by COPD and attend a follow-up interview. An Interpretative Phenomenological Analysis method was used to analyze the data. Data saturation was reached by the seventh patient.

RESULTS

COPD and the resulting breathlessness had a profound and diverse impact on our participants' lives. Living with COPD required substantial changes to how everyday tasks are performed, and participants learnt new strategies to deal with such tasks. A mixture of active and passive coping styles was evident. Feelings of frustration, anxiety and a sense of isolation were also reported. Contextual factors impacting ADLs included challenging climatic conditions and the local popularity of traditional or alternative medicine.

CONCLUSION

The photovoice technique improved our understanding of the lived experiences of COPD patients and can benefit those who struggle to articulate their views by offering a different way to communicate beyond conventional interviewing.

Physical activity and sedentary behaviour in patients admitted with COPD: Associated factors

AIM

To establish amongst a cohort of patients admitted with Chronic Obstructive Pulmonary Disease which factors were associated with their level of Physical Activity and Sedentary Behavior prior to the admission event.

METHODS

Prospective observational cohort study. Nine Spanish hospitals participated. Patients were recruited consecutively. Variables relating to the patients' clinical baseline status were recorded, including the COPD Assessment test, the HADS anxiety-depression test, comorbidities and the Yale Physical Activity Survey. Data relating to admission and up to two months after discharge were also recorded.

RESULTS

1638 COPD patients were studied, with a mean age of 72.39 (SD 10.33), 76.56 % male, FEV1 49.41 % (SD19.19), Charlson index 2. The level of PA at baseline was 30.79 points (SD 22.43). Multivariable linear regression analysis identified the following as being associated with low PA: older age, obesity, higher level of hemoglobin, lower score of Barthel index, which means disability, health related quality of life (EuroQoL-5d and CAT) and dyspnea. Variables associated with sedentary behavior were: older age, presence of obstructive apnea syndrome, higher disability, presence of depressive symptoms and dyspnea.

CONCLUSIONS

In a cohort of hospitalized COPD patients, we have found several variables, some of them modifiable, associated with physical activity/inactivity and sedentary behavior.

Targeting biophysical microenvironment for improved treatment of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is responsible for high disability rates, high death rates, and significant cost to health systems. Growing evidence in recent decades shows significant biophysical microenvironment changes in COPD, impacting lung tissues, cells, and treatment response. Furthermore, such biophysical changes have shown great potential as novel targets for improved therapeutic strategy of COPD, where both pharmacological and non-pharmacological therapies focusing on repairing the biophysical microenvironment of the lung have emerged. We present the first comprehensive review of four distinct biophysical hallmarks [i.e., extracellular matrix (ECM) microarchitecture, stiffness, fluid shear stress, and mechanical stretch] in COPD, the possible involvement of pathological changes, possible effects, and correlated in vitro models and sum up the emerging COPD treatments targeting these biophysical hallmarks.

Comparison of Physical Activity Patterns among Three Major Chronic Respiratory Diseases

Although the level of physical activity in daily life (PADL) plays a vital role concerning the health of subjects with chronic lung diseases, it remains uncertain how PADL patterns compare among different conditions. This study's objective was to compare the PADL levels of subjects with COPD, asthma and idiopathic pulmonary fibrosis (IPF); and to investigate PADL behaviour in different diseases' severity. Stable subjects who had not undergone pulmonary rehabilitation in the previous year were included. Subjects were divided into two subgroups according to disease severity: mild/moderate and severe/very severe. The primary outcome was time spent in moderate-to-vigorous physical activities (MVPA) (Actigraph GT3x) measured during one week over 12 h/day; other assessments included pulmonary function, peripheral muscle strength and exercise capacity. Comparisons among subgroups were corrected for age, BMI and sex. The analysis involved 119 subjects (47 asthma, 48 COPD and 24 IPF). Subjects with asthma had higher PADL levels than those with COPD and IPF (MVPA 18(14-22) vs. 8(4-12) vs. 7(1-12) min/day, respectively; p ancova = 0.002). Subjects with severe/very severe IPF had the lowest PADL level among all subgroups. Adult subjects with asthma have higher PADL levels than those with COPD and IPF, whereas patients with severe and very severe IPF are the most physically inactive subjects.

Effects of Pedometer-Based Step-Feedback on Physical Activity of Severe COPD Patients

Purpose

This study investigated whether adding step-feedback (step-FB) from a pedometer to pulmonary rehabilitation (PR) programs could increase the physical activity (PA) of low-activity patients with severe chronic obstructive pulmonary disease (COPD).

Patients and Methods

We included low-activity patients with severe COPD (step-FB group: 14 patients; control group: 17 patients) who underwent PR for the first time. The usual PR program for patients with severe COPD consisted of two 8-week sessions (PR session 1: PR1, PR session 2: PR2). The step-FB group was provided a program with step-FB added to PR2 (PR2+step-FB). Furthermore, all patients were evaluated at pre-intervention (baseline), PR1, and PR2. The primary outcome of this study was the number of daily steps (steps) and energy expenditure from activity (energy expenditure), as measured by a pedometer. The secondary outcomes were dyspnea and exercise tolerance.

Results

In PR1, dyspnea, exercise tolerance, steps, and energy expenditure were significantly improved as compared to baseline, in both groups. During PR2, dyspnea and exercise tolerance were significantly improved as compared to PR1, in both groups. Steps and energy expenditure were significantly improved in the step-FB group, but not in the control group.

Conclusion

PR improved PA by improving physical function in severe COPD patients. Adding step-FB improved PA in severe COPD patients by presenting an activity goal for improving PA. Therefore, pedometer-based step-FB is a viable addition to PR and has the potential to improve PA continuously in these patients.

Sustaining training effects through physical activity coaching (STEP): a randomized controlled trial

BACKGROUND

Pulmonary rehabilitation (PR) programs improve physical fitness, symptoms and quality of life (QoL) of patients with COPD. However, improved physical activity (PA) is not guaranteed after PR and the clinical benefits fade off after PR discharge. We aimed to investigate whether a 9 months PA-telecoaching program is able to improve PA of patients with COPD, after 3 months of PR and if this leads to maintenance of PR-acquired benefits.

METHODS

Patients with COPD enrolled in a 6-month PR program were randomized to a (semi-automated) PA-telecoaching program or usual care, 3 months after PR initiation. The intervention consisted of a smartphone application with individual targets and feedback (for 6 months) and self-monitoring with a step counter (for 9 months). Patients were followed up for 9 months after randomization. Primary outcome was PA (daily step count by accelerometery), secondary outcomes were exercise tolerance, quadriceps force, dyspnea and QoL.

RESULTS

Seventy-three patients were included (mean ± SD: 65 ± 7 years, FEV1 49 ± 19%, 6MWD 506 ± 75 m, PA 5225 ± 2646 steps/day). The intervention group presented a significant improvement in steps/day at every visit compared to usual care (between-group differences mean ± SE: 1431 ± 555 steps/day at 9 months after randomization, p = 0.01). Secondary outcomes did not differ between the groups.

CONCLUSION

The semi-automated PA-telecoaching program implemented after 3 months of PR was effective to improve the amount of PA (steps/day) during PR and after follow-up. However, this was not accompanied by the maintenance of other PR-acquired benefits.

TRIAL REGISTRATION

ClinicalTrials.gov. Identifier: NCT02702791. Retrospectively registered on March 9, 2016. Start study October 2015. https://clinicaltrials.gov/ct2/show/NCT02702791?term=NCT02702791&draw=2&rank=1 .

Depression Symptoms and Physical Activity in Veterans With COPD: Insights From a Web-Based, Pedometer-Mediated Physical Activity Intervention

BACKGROUND

Depression is known to limit physical activity (PA) among individuals with chronic obstructive pulmonary disease (COPD). However, whether and how depression influences the effectiveness of PA interventions is unknown.

PURPOSE

The study examined the association between baseline depression symptoms and change in daily step count and whether group assignment to a web-based, pedometer-mediated PA intervention moderated the association between baseline depression symptoms and change in daily step count.

METHODS

Secondary analysis included two cohorts of U.S. Veterans with COPD (n = 212; 97% male; mean age 69 ± 8 years) assessed at baseline and 3 months. Cohorts 1 and 2 were randomly assigned to the same PA intervention (n = 111) or a control group (n = 101). Multivariate regressions tested the main effects of baseline depression symptoms (BDI-II total and cognitive-affective and somatic subscales) on change in daily steps, as well as the interaction between baseline BDI-II and subscales and group assignment on change in daily steps.

RESULTS

Greater BDI-II total score (B = -31.8, SE = 14.48, p = .030) and somatic subscale scores (B = -99.82, SE = 35.76, p = .006) were associated with less improvement in daily step count. There was a significant interaction between baseline cognitive-affective subscale and the intervention predicting change in daily step count (B = -88.56, SE = 42.31, p = .038). When cognitive-affective subscale scores were ≥1 SD above the mean, the intervention was no longer associated with an increase in daily step count (p = .585).

CONCLUSIONS

Depression should be routinely assessed and targeted as part of PA promotion efforts.

Predictors of longitudinal changes in body weight, muscle and fat in patients with and ever-smokers at risk of COPD

BACKGROUND AND OBJECTIVE

Weight and muscle loss are predictors of poor outcomes in chronic obstructive pulmonary disease. However, to our knowledge, no study has investigated the predictors of longitudinal weight loss or its composition from functional and morphological perspectives.

METHODS

This longitudinal observational study with a median follow-up period of 5 years (range: 3.0-5.8 years) included patients with COPD and ever-smokers at risk of COPD. Using chest computed tomography (CT) images, airway and emphysematous lesions were assessed as the square root of the wall area of a hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10) and the percentage of low attenuation volume (LAV%). Muscle mass was estimated using cross-sectional areas (CSAs) of the pectoralis and erector spinae muscles, and fat mass was estimated using the subcutaneous fat thickness at the level of the 8th rib measured using chest CT images. Statistical analyses were performed using the linear mixed-effects models.

RESULTS

In total, 114 patients were enrolled. Their body mass index remained stable during the study period while body weight and muscle CSA decreased over time and the subcutaneous fat thickness increased. Reduced forced expiratory volume in 1 s and peak expiratory flow (PEF) at baseline predicted the future decline in muscle CSA.

CONCLUSION

Severe airflow limitation predicted future muscle wasting in patients with COPD and ever-smokers at risk of COPD. Airflow limitation with a PEF slightly below 90% of the predicted value may require intervention to prevent future muscle loss.

Determinants of Activity Phenotype in Patients with Chronic Obstructive Pulmonary Disease

Introduction

Physical activity (PA) and sedentary behavior (SB) have attracted attention in chronic obstructive pulmonary disease (COPD), and there have been efforts to evaluate PA and SB separately. The factors associated with the characteristics of the four activity phenotypes defined by the durations of PA and SB are largely unknown. The aim of this study was to clarify the factors that could differentiate each activity phenotype.

Materials and Methods

Study subjects were outpatients with stable COPD who were ≥40 years of age. We investigated the influence of 26 different factors on the activity phenotypes of COPD and extracted the factors that showed significant differences among the four activity phenotypes.

Results

Two hundred sixteen patients were included in the analysis. Exercise capacity and dyspnea were determinants that distinguished the low PA groups from the high PA groups. The pulmonary function and desaturation during exercise were factors that distinguished the high PA with low SB group from the low PA with high SB group. BMI, grip strength, upper arm circumference and HbA1c were higher in the low PA and low SB group than in the low PA and high SB group.

Conclusion

These factors could be the determinants discriminating activity phenotypes of patients with COPD.

[Pulmonary Rehabilitation]

Reduced exercise capacity, skeletal muscle dysfunction, and a physically inactive lifestyle are linked with symptoms of fatigue and dyspnea in people suffering from chronic lung disease. Numerous such extrapulmonary manifestations have been identified as treatable aspects of pulmonary rehabilitation (PR). PR is an extensive personalized non-pharmaceutical intervention, encompassing, but not limited to, exercise training, respiratory therapy, and education. The content and goals of a PR-program are based on a comprehensive patient assessment at the time of rehabilitation admission, with personalized therapies provided by a multidisciplinary team of healthcare professionals. This article provides an overview of PR including possible indications, therapy contents (e. g. exercise training, respiratory therapy), and evidence (COPD, interstitial lung disease, COVID-19). Finally, options for pulmonary rehabilitation maintenance services in Germany are presented.

The effects of an innovative GP-physiotherapist partnership in improving COPD management in primary care

BACKGROUND

Evidence suggests that management of people with Chronic Obstructive Pulmonary Disease (COPD) in primary care has been suboptimal, in particular, with low referral rates to pulmonary rehabilitation (PR). The aim of this study was to evaluate the effectiveness of a GP-physiotherapist partnership in optimising management of COPD in primary care.

METHODS

A pragmatic, pilot, before and after study was conducted in four general practices in Australia. A senior cardiorespiratory physiotherapist was partnered with each general practice. Adults with a history of smoking and/or COPD, aged ≥ 40 years with ≥ 2 practice visits in the previous year were recruited following spirometric confirmation of COPD. Intervention was provided by the physiotherapist at the general practice and included PR referral, physical activity and smoking cessation advice, provision of a pedometer and review of inhaler technique. Intervention occurred at baseline, one month and three months. Main outcomes included PR referral and attendance. Secondary clinical outcomes included changes in COPD Assessment Test (CAT) score, dyspnoea, health activation and pedometer step count. Process outcomes included count of initiation of smoking cessation interventions and review of inhaler technique.

RESULTS

A total of 148 participants attended a baseline appointment where pre/post bronchodilator spirometry was performed. 31 participants with airflow obstruction on post-bronchodilator spirometry (mean age 75yrs (SD 9.3), mean FEV₁% pred = 75% (SD 18.6), 61% female) received the intervention. At three months, 78% (21/27) were referred to PR and 38% (8/21) had attended PR. No significant improvements were seen in CAT scores, dyspnoea or health activation. There was no significant change in average daily step count at three months compared to baseline (mean difference (95% CI) -266 steps (-956 to 423), p = 0.43). Where indicated, all participants had smoking cessation interventions initiated and inhaler technique reviewed.

CONCLUSION

The results of this study suggest that this model was able to increase referrals to PR from primary care and was successful in implementing some aspects of COPD management, however, was insufficient to improve symptom scores and physical activity levels in people with COPD.

TRIAL REGISTRATION

ANZCTR, ACTRN12619001127190. Registered 12 August 2019 - Retrospectively registered, http://www.ANZCTR.org.au/ACTRN12619001127190.aspx .

Assessment of sedentary behaviour in individuals with COPD: how many days are necessary?

Objective

The objective of the present study was to define the minimum number of monitoring days required for the adequate cross-sectional assessment of sedentary behaviour in individuals with chronic obstructive pulmonary disease (COPD).

Methods

In this cross-sectional study, the sedentary behaviour of individuals with COPD was assessed using two physical activity monitors during awake time for seven consecutive days. Time spent per day in activities requiring ≤1.5 metabolic equivalents (METs) and in sitting, lying and sitting+lying positions was calculated taking into account the average of 7 days (as a reference in all analyses) and of all 119 possible combinations of 2---6 days. Intraclass correlation coefficients (ICCs) and linear regression analyses were performed for all combinations.

Results

91 individuals were analysed (47 female, 66±9 years, forced expiratory volume in 1 s 50±15% predicted). For the variables time spent per day in activities ≤1.5METs and sitting, the average of any combination of at least four assessment days was sufficient to adequately reflect the average of 7 days (adjusted R2≥0.929, ICC≥0.962, p<0.0001 for all). For time spent per day lying and sitting+lying, only two assessment days were enough (adjusted R2≥0.937, ICC≥0.968, p<0.0001 for all). Results were maintained independently of patient sex, disease severity, day of the week, daylight time or daytime naps.

Conclusions

The average of 4 days of objective monitoring was sufficient to adequately reflect the results of a 1-week assessment of the main outcomes related to sedentary behaviour in individuals with moderate to very severe COPD, regardless of sex, disease severity, day of the week, daylight time and occurrence of daytime naps.

Utility of the Shortness of Breath in Daily Activities Questionnaire (SOBDA-Q) to Detect Sedentary Behavior in Patients with Chronic Obstructive Pulmonary Disease (COPD)

Sedentary behavior has been shown to be an independent predictor of mortality in patients with chronic obstructive pulmonary disease (COPD). However, physicians have difficulty ascertaining patients' activity levels because they tend to avoid shortness of breath. The reformed shortness of breath (SOB) in the daily activities questionnaire (SOBDA-Q) specifies the degree of SOB by measuring low-intensity activity behavior in everyday living. Therefore, we aimed to explore the utility of the SOBDA-Q in detecting sedentary COPD. We compared the modified Medical Research Council dyspnea scale (mMRC), COPD assessment test (CAT), and SOBDA-Q with physical activity levels (PAL) in 17 healthy patients, 32 non-sedentary COPD patients (PAL ≥ 1.5 METs·h), and 15 sedentary COPD patients (PAL < 1.5 METs·h) in this cross-sectional study. CAT and all domains of the SOBDA-Q in all patients are significantly correlated with PAL, even after adjusting for age. The dietary domain has the highest specificity, and the outdoor activity domain has the highest sensitivity for detecting sedentary COPD. Combining these domains helped determine patients with sedentary COPD (AUC = 0.829, sensitivity = 1.00, specificity = 0.55). The SOBDA-Q is associated with PAL and could be a useful tool for determining patients with sedentary COPD. Moreover, eating and outing inactivity claims reflect sedentary behavior in patients with COPD.

Bibliometric Analysis of Exercise and Chronic Obstructive Pulmonary Disease

Background

Chronic Obstructive Pulmonary Disease (COPD) is the leading cause of death in the world. Pulmonary rehabilitation includes, but is not limited to, exercise training and education, which aim to improve the physical and psychological conditions of patients with chronic respiratory diseases through self-management interventions.

Objective

The aim of this study was to perform a bibliometric analysis of studies on exercise and COPD published from 2000 to 2021 using VOSviewer and CiteSpace.

Methods

All included literature was obtained from the Web of Science core collection. VOSviewer was used to analyze country or region, institution, major co-cited journals, and keywords. CiteSpace was used to analyze centrality, author and co-cited authors, journals, the strongest citation bursts of references, and keywords.

Results

A total of 1889 articles meeting the criteria were obtained. The United States has the largest number of publications. The American Journal of Respiratory and Critical Care Medicine is the most influential in this field, and the most published research institution is Queen's University. Denis E. O'Donnell has made significant contributions to exercise and COPD research. Association, impact, and statement are hot spots of research in this field.

Conclusion

A bibliometric analysis of exercise interventions for COPD over the past 22 years provides direction for future research.

Objective Measurement of Physical Activity and Sedentary Behavior in Patients with Chronic Obstructive Pulmonary Disease: Points to Keep in Mind during Evaluations

Objective measurement methods using accelerometers have become the mainstream approach for evaluating physical activity (PA) and sedentary behavior (SB). However, several problems face the objective evaluation of PA and SB in patients with chronic obstructive pulmonary disease (COPD). For example, indicators of PA differ depending on whether the accelerometer detects the kind of activity on the one hand, or its intensity on the other. Measured data are also strongly influenced by environmental factors (weather, season, employment status, etc.) and methodological factors (days with uncommon activities, non-wearing time, minimum required wearing time per day, minimum number of valid days required, etc.). Therefore, adjusting for these factors is required when evaluating PA or SB, especially when evaluating the effects of intervention. The exclusion of sleeping time, unification of total measurement time, and minimization of the required wearing time per day might be more important for the evaluation of ST than for evaluating PA. The lying-down-time-to-sitting-time ratio was shown to be larger in COPD patients than in healthy subjects. In this review, we clarified the problems encountered during objective evaluations of PA and SB in patients with COPD and encouraged investigators to recognize the presence of these problems and the importance of adjusting for them.

Computed Tomography Lung Density Analysis: An Imaging Biomarker Predicting Physical Inactivity in Chronic Obstructive Pulmonary Disease: A Pilot Study

Physical inactivity correlates with poor prognosis in chronic obstructive pulmonary disease (COPD) and is suggested to be related to lung hyperinflation. We examined the association between physical activity and the expiratory to inspiratory (E/I) ratio of mean lung density (MLD), the imaging biomarker of resting lung hyperinflation. COPD patients (n = 41) and healthy controls (n = 12) underwent assessment of pulmonary function and physical activity with an accelerometer, as well as computed tomography at full inspiration and expiration. E/I_MLD was calculated by measuring inspiratory and expiratory MLD. Exercise (EX) was defined as metabolic equivalents × duration (hours). COPD patients had higher E/I_MLD (0.975 vs. 0.964) than healthy subjects. When dividing COPD patients into sedentary (EX < 1.5) and non-sedentary (EX ≥ 1.5) groups, E/I_MLD in the sedentary group was statistically higher than that in the non-sedentary group (0.983 vs. 0.972). E/I_MLD > 0.980 was a good predictor of sedentary behavior in COPD (sensitivity, 0.815; specificity, 0.714). Multivariate analysis showed that E/I_MLD was associated with sedentary behavior (odds ratio, 0.39; p = 0.04), independent of age, symptomology, airflow obstruction, and pulmonary diffusion. In conclusion, higher E/I_MLD scores are associated with sedentary behavior and can be a useful imaging biomarker for the early detection of physical inactivity in COPD.

Change in physical activity related to admission for exacerbation in COPD patients

INTRODUCTION

The aim of this study was to determine the impact of hospitalizations on levels of physical activity (PA) and whether other factors were associated with subsequent changes in PA.

METHODS

Prospective observational cohort study with a nested case-control study, with follow-up 60 days from the index hospital admission. Nine hospitals participated in the study. Patients were recruited consecutively. Several variables and questionnaires of the clinical baseline status of the patients were recorded including: the COPD Assessment Test (CAT), the Hospital Anxiety-Depression scale (HADS), comorbidities and the Yale Physical Activity Survey. Patients' data related to admission and up to two months after discharge were also recorded.

RESULTS

883 patients were studied: 79.7% male; FEV1 48%; Charlson index 2; 28.7% active smokers. The baseline PA level for the total sample was 23 points. A statistically significant difference in PA was found between patients readmitted up to 2 months after the index admission and those not readmitted (17vs. 27, p < 0.0001). Multivariable linear regression analysis identified the following as predictors of the decrease of PA from baseline (index admission) up to 2 months follow-up: admission for COPD exacerbation in the two months prior to the index admission; readmission up to 2 months after the index admission; baseline HAD depressive symptoms, worse CAT score, and patient-reported "need for help".

CONCLUSIONS

In a cohort of admitted COPD patients, we identified a strong relationship between hospitalization for exacerbation and PA. In addition, some other potentially modifiable factors were found associated with the change in PA level after an admission.

Dissociation between physical capacity and daily physical activity in COPD patients. A population-based approach

BADKGROUND

Physical capacity (PC) and daily physical activity (PA) are two crucial factors in the clinical course of COPD, although they do not always maintain a close relationship. The objectives were to evaluate the frequency of PC-PA dissociation in patients with COPD and subjects without airflow limitation (AL) and to identify its risk factors.

METHODS

A sample of 319 COPD patients and 399 subjects without AL was consecutively obtained from a population-based sample of 9092 subjects evaluated in the EPISCAN II study. Baseline evaluation included clinical questionnaires, lung function testing, blood analysis and low-dose computed tomography (CT) scan with evaluation of lung density and airway wall thickness. A distance walked in 6 min > 70% predicted was considered an indicator of normal PC, while a Yale Physical Activity Survey summary index score <51 was used to identify with sedentary lifestyle.

RESULTS

166 COPD patients (52.0%) reported a sedentary lifestyle with evidence of preserved PC, while this phenomenon was present in 188 (47.1%) subjects without AL. In the COPD group, symptoms of chronic bronchitis, depression and elevated hematocrit and blood eosinophil count were identified as independent risk factors for PC-PA dissociation. In turn, in the subjects without AL, the risk factors for PC-PA dissociation were low fat-free mass, obesity and anxiety, as well as reduced levels of HDL-cholesterol and the absence of osteoporosis.

CONCLUSIONS

Almost half of COPD patients and subjects without airflow limitation with preserved PC maintain a sedentary lifestyle, with different risk factors for sedentarism between both groups.

The efficacy and safety of additional treatment with short-acting muscarinic antagonist combined with long-acting beta-2 agonist in stable patients with chronic obstructive pulmonary disease: A systematic review and meta-analysis

BACKGROUND

The rationale for additional treatment with short-acting bronchodilators combined with long-acting bronchodilators for patients with chronic obstructive pulmonary disease (COPD) is not adequately studied.

METHODS

We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of a short-acting muscarinic antagonist (SAMA) therapy combined with a long-acting beta-2 agonist (LABA) in patients with stable COPD. Pulmonary function, dyspnea, health-related quality of life, exercise tolerance, physical activity, exacerbations of COPD, and adverse events during regular use were set as outcomes of interest.

RESULTS

We included five controlled trials including two sets of publicly available online data without article publications for the meta-analysis. Additional use of SAMA plus LABA showed a significant improvement in the peak response in FEV₁ (mean difference (MD) 98.70 mL, p < .00001), transitional dyspnea index score (MD .85, p = .02), and St George's Respiratory Questionnaire score (MD -2.00, p = .008) compared to LABA treatment. There was no significant difference in the risk of exacerbation of COPD (p = .20) and only a slight trend of increased severe adverse events (OR: 2.16, p = .08) and cardiovascular events (OR: 2.38, p = .06).

CONCLUSION

Additional treatment with SAMA combined with LABA could be a feasible choice due to its efficacy and safety.

The Impact of Depression and Exercise Self-Efficacy on Benefits of Pulmonary Rehabilitation in Veterans with COPD

Pulmonary rehabilitation (PR) improves health-related quality of life (HRQoL) and exercise capacity. Little is known about the impact of depression symptoms and exercise self-efficacy on improvements in these key PR outcomes. This study examined the impact of baseline depression status and change in depression symptoms (Beck Depression Inventory-II [BDI-II] score) over the course of PR on change in HRQoL assessed by the Chronic Respiratory Disease Questionnaire-Self Reported (CRQ-SR) and exercise capacity as measured by the 6-Minute Walk Test (6MWT). We also examined whether baseline exercise self-efficacy moderated the association between baseline depression symptoms and change in these key PR outcomes. We studied 112 US veterans (aged 70.38 ± 8.49 years) with chronic obstructive pulmonary disease (COPD) who completed PR consisting of twice-weekly 2-hour classes for 18 sessions. Depressed (BDI-II >13) and nondepressed (BDI-II ≤13) patients at baseline demonstrated comparable and significant improvement in CRQ-SR total score, subscales, and 6MWT. Greater reduction in depression over the course of treatment was significantly associated with greater improvement in CRQ-SR total score and the following subscales: fatigue, mastery, and emotional function. Change in depression did not predict change in 6MWT distance. Baseline exercise self-efficacy moderated the association between baseline depression symptoms and change in CRQ-SR fatigue. Specifically, when baseline exercise self-efficacy was <30.4, greater baseline depression was associated with less improvement in CRQ-SR fatigue. When baseline self-efficacy was >152.0, greater baseline depression was associated with greater improvement in CRQ-SR fatigue. PR programs should address mood and confidence to exercise given their impact on key PR outcomes.

Physical activity, physical capacity and sedentary behavior among asthma patients

BACKGROUND: Although exercise and daily physical activity (PA) have long been known to benefit patients with chronic disorders, knowledge is limited regarding asthma.

OBJECTIVE: In a Danish setting, our aim was to measure physical activity, sedentary behavior, and physical capacity among patients with asthma. We hypothesized that people with severe asthma would be less active and more sedentary than their mild-moderate counterparts.

METHODS: Adults with asthma were recruited through respiratory outpatient clinics and subsequently examined twice, 4 weeks apart. At each visit, participants underwent a series of lung function tests, questionnaires, and maximum oxygen uptake testing (VO₂max). Between the visits, participants wore an accelerometer continuously for 4 weeks, measuring sedentary time and daily steps. Sixty patients, 27 with mild-moderate asthma (GINA 1–3) and 33 with severe asthma (GINA 4–5), completed both visits and had valid accelerometer measurements.

RESULTS: No significant differences between the two groups were found in sedentary time, number of steps or VO₂max.   VO₂max was significantly correlated with FeNO (r = −0.30, p < 0.05), Short Form-12 Mental Health (r = 0.37, p < 0.05), Asthma Control Questionnaire (r = −0.35, p < 0.05), and Mini Asthma Quality of Life Questionnaire (r = 0.36, p < 0.05).

CONCLUSION: No differences were observed between patients with mild-moderate and severe asthma regarding sedentary behavior, daily steps or level of cardiopulmonary fitness. Furthermore, patients with the highest VO₂max had the higher quality of life scores.

Abbreviations: VO₂max: Maximal Oxygen Uptake; CPET: Cardiopulmonary Exercise Testing; BMI: Body Mass Index; FEV1: Forced Expired Volume in the First Second; FVC: Forced Vital Capacity; PEF: Peak Expiratory Flow; EIB: Exercise-Induced Bronchoconstriction; COPD: Chronic Obstructive Pulmonary Disease; ACQ: Asthma Control Questionnaire; Mini-AQLQ: Mini Asthma Quality of Life Questionnaire; SF-12: Short Form 12 Health Survey; SNOT-22: Sino-Nasal Outcome Test 22; GINA: The Global Initiative for Asthma; CRP: C-reactive Protein; Hgb:Hemoglobin count; EOS: Eosinophil count; EVH: Eucapnic Voluntary Hyperventilation; FeNO: Fractional Exhaled Nitric Oxide; PA: Physical Activity ERS: European Respiratory Society; ATS: American Thoracic Society; CRS: Chronic Rhinosinusitis; AHR: Airway Hyperresponsiveness

A Call for Action on Chronic Respiratory Diseases within Physical Activity Policies, Guidelines and Action Plans: Let's Move!

Global policy documents for the promotion of physical activity (PA) play an important role in the measurement, evaluation, and monitoring of population PA levels. The World Health Organisation (WHO) guidelines include, for the first time, recommendations for specific populations, including individuals living with a range of non-communicable diseases. Of note, is the absence of any chronic respiratory diseases (CRDs) within the recommendations. Globally, CRDs are highly prevalent, are attributable to significant individual and societal burdens, and are characterised by low PA. As a community, there is a need to come together to understand how to increase CRD representation within global PA policy documents, including where the evidence gaps are and how we can align with PA research in other contexts. In this commentary, the potential for synergy between evidence into the relationships between PA in CRDs globally and the relevance to current policies, guidelines and action plans on population levels of PA are discussed. Furthermore, actions and considerations for future research, including the need to harmonize and promote PA assessment (particularly in low- and middle-income countries) and encompass the synergistic influences of PA, sedentary behaviour and sleep on health outcomes in CRD populations are presented.

Discriminant Validity of a Single Clinical Question for the Screening of Inactivity in Individuals Living with COPD

Introduction

Quantifying physical activity in chronic obstructive pulmonary disease (COPD) with questionnaires and activity monitors in clinical practice is challenging. The aim of the present study was to analyse the discriminant validity of a single clinical question for the screening of inactive individuals living with COPD.

Methods

A multicentre study was carried out in stable COPD individuals both in primary and tertiary care. Patients wore the Dynaport accelerometer for 8 days and then answered 5 physical activity questions developed for the study, referring to the week in which their physical activity was monitored. Receiver operating characteristic (ROC) curve analysis with physical activity level (PAL) as the gold standard reference was used to determine the best cut-off point for each of the 5 clinical physical activity questions tested.

Results

A total of 86 COPD participants were analysed (males 68.6%; mean (SD) age 66.6 (8.5) years; FEV₁ 50.9 (17.3)% predicted; mean of 7305 (3906) steps/day). Forty-two (48.8%) participants were considered physically inactive (PAL ≤1.69). Answers to 4 out of 5 questions significantly differed in active vs inactive patients. The Kappa index and ROC curves showed that the answer to the question "On average, how many minutes per day do you walk briskly?" had the best discriminative capacity for inactivity, with an area under the curve (AUC) (95% Confidence interval (CI)) of 0.73 (0.63-0.84) and 30 min/day was identified as the best cut-off value (sensitivity (95% CI): 0.75 (0.60-0.87); specificity: 0.76 (0.61-0.88)).

Conclusion

The present results indicate that self-reported brisk walk time lower than 30 min/day may be a valid tool for the screening of inactivity in individuals living with COPD in routine care, if more detailed physical activity measures are not feasible.

Cross-sectional study of pain-related variables before and during the COVID-19 pandemic in patients with COPD

BACKGROUND

The impact of the COVID-19 pandemic influences of COPD patients. The worsening of their health status may contribute to a higher pain prevalence.

AIM

The aim of this study was to analyze the pain-related variables before and during the COVID-19 pandemic in patients with chronic obstructive pulmonary disease.

METHODS

In this cross-sectional case-control study, stable patients with chronic obstructive pulmonary disease without a COVID-19 diagnosis were evaluated before and during the pandemic. The main outcomes were the pronociceptive pain profile (general pain sensitivity, pain intensity, pain interference, and pressure pain sensitivity) and the psychological vulnerability (perceived health status, anxiety, and depression).

RESULTS

Our results showed that patients with chronic obstructive pulmonary disease during COVID-19 pandemic experienced higher general pain sensitivity and intensity with statistical differences in pain interference (p < .001), being the overall perceived health status lower than before the pandemic (p < .05).

CONCLUSIONS

We concluded that patients with chronic obstructive pulmonary disease during the COVID-19 pandemic showed a rise the pronociceptive pain profile accompanied by increased psychological vulnerability.

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 VO_2peak 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.

Validation of Simple Prediction Equations for Step Count in Japanese Patients with Chronic Obstructive Pulmonary Disease

Physical activity is decreased in patients with chronic obstructive pulmonary disease, and decreased physical activity leads to a poor prognosis. To determine an individual’s target step count from the measured step counts and predicted step counts, simple and detailed prediction equations for step count were developed. To verify the validity of the simple prediction equation, the validity of the simple equation was evaluated in a different cohort and the correlation between the step counts calculated by the simple equation and those by the detailed prediction equation were evaluated. When the step counts calculated by the simple prediction equation for all participants were compared with the measured step counts, a significant correlation was obtained among them, and the calculated values were found to be reproducible with the measured values in patients with a measured step count of <6500 by Bland−Altman plots. Furthermore, the values calculated by the simple prediction equation and those calculated by the detailed prediction equation showed a significant correlation. In conclusion, the simple prediction equation was considered reasonable.

Predictors and changes of physical activity in idiopathic pulmonary fibrosis

Background

Different clinical predictors of physical activity (PA) have been described in idiopathic pulmonary fibrosis (IPF), but studies are lacking evaluating the potential role of muscle strength and anxiety and depression symptoms in PA limitation. Moreover, little is known about the impact of changes in PA in the course of the disease. The aim of the present study was to investigate the relationship between baseline PA and a wide range of variables in IPF, to assess its longitudinal changes at 12 months and its impact on progression free-survival.

Methods

PA was assessed by accelerometer and physiological, clinical, psychological factors and health-related quality of life were evaluated in subjects with IPF at baseline and at 12 month follow-up. Predictors of PA were determined at baseline, evolution of PA parameters was described and the prognostic role of PA evolution was also established.

Results

Forty participants with IPF were included and 22 completed the follow-up. At baseline, subjects performed 5765 (3442) daily steps and spent 64 (44) minutes/day in moderate to vigorous PA. Multivariate regression models showed that at baseline, a lower six-minute walked distance, lower quadriceps strength (QMVC), and a higher depression score in the Hospital Anxiety and Depression scale were associated to lower daily step number. In addition, being in (Gender-Age-Physiology) GAP III stage, having a BMI ≥ 25 kg/m² and lower QMVC or maximum inspiratory pressure were factors associated with sedentary behaviour. Adjusted for age, gender and forced vital capacity (FVC) (%pred.) a lower progression-free survival was evidenced in those subjects that decreased PA compared to those that maintained, or even increased it, at 12 months [HR 12.1 (95% CI, 1.9–78.8); p = 0.009].

Conclusion

Among a wide range of variables, muscle strength and depression symptoms have a predominant role in PA in IPF patients. Daily PA behaviour and its evolution should be considered in IPF clinical assessment and as a potential complementary indicator of disease prognosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02134-4.

Machine Learning-Based 30-Day Hospital Readmission Predictions for COPD Patients Using Physical Activity Data of Daily Living with Accelerometer-Based Device

Chronic obstructive pulmonary disease (COPD) is a significantly concerning disease, and is ranked highest in terms of 30-day hospital readmission. Generally, physical activity (PA) of daily living reflects the health status and is proposed as a strong indicator of 30-day hospital readmission for patients with COPD. This study attempted to predict 30-day hospital readmission by analyzing continuous PA data using machine learning (ML) methods. Data were collected from 16 patients with COPD over 3877 days, and clinical information extracted from the patients’ hospital records. Activity-based parameters were conceptualized and evaluated, and ML models were trained and validated to retrospectively analyze the PA data, identify the nonlinear classification characteristics of different risk factors, and predict hospital readmissions. Overall, this study predicted 30-day hospital readmission and prediction performance is summarized as two distinct approaches: prediction-based performance and event-based performance. In a prediction-based performance analysis, readmissions predicted with 70.35% accuracy; and in an event-based performance analysis, the total 30-day readmissions were predicted with a precision of 72.73%. PA data reflect the health status; thus, PA data can be used to predict hospital readmissions. Predicting readmissions will improve patient care, reduce the burden of medical costs burden, and can assist in staging suitable interventions, such as promoting PA, alternate treatment plans, or changes in lifestyle to prevent readmissions.

Objective physical activity level is associated with rectus femoris muscle echo‐intensity in patients with chronic obstructive pulmonary disease

Introduction

Skeletal muscle dysfunction is one of the major extrapulmonary complications of chronic obstructive pulmonary disease (COPD). Some studies have reported a relationship between physical activity (PA) level and skeletal muscle quality assessed by echo‐intensity (EI) in healthy individuals but not in patients with COPD.

Objectives

The aim of this study is to investigate the relationships between PA level and both skeletal muscle EI and skeletal muscle mass in patients with COPD.

Methods

We employed a cross‐sectional design. Forty male outpatients with stable COPD were enrolled. Using B‐mode ultrasonography, we measured the rectus femoris muscle cross‐sectional area (RF‐CSA) and EI (RF‐EI). The RF‐CSA and RF‐EI were measured on frozen images using an electronic caliper and 8‐bit gray‐scale analysis, respectively. The objective PA level was determined by monitoring daily step counts and moderate‐to‐vigorous physical activity time (MVPA) with an activity monitor. A general regression model was used to assess the relationships between PA level and both RF‐CSA and RF‐EI. Age and body mass index (BMI) were adopted as confounding variables.

Results

Twenty‐five outpatients with stable COPD (age, 70 ± 7 years old; forced expiratory volume in 1 s, 55.0 ± 24.9% of predicted values) were finally enrolled in the present study. Even after adjusting for age and BMI, the daily step counts and MVPA were significantly associated with RF‐EI, and knee extensor force was associated with RF‐CSA.

Conclusion

The present study showed that PA level was associated with RF‐EI in patients with COPD. In addition, RF‐CSA was associated with knee extensor force. When assessing skeletal muscle using ultrasonography in patients with COPD, we should also assess EI.

Impact of extrapulmonary comorbidities on physical activity in chronic obstructive pulmonary disease in Japan: A cross-sectional study

Physical activity, which can be affected by airflow limitation and extrapulmonary comorbidities, has been reported to be reduced in patients with chronic obstructive pulmonary disease, and reduced physical activity is associated with higher risks of exacerbation and mortality. The aim of the present study is to elucidate the comprehensive effect of extrapulmonary comorbidities on physical activity in Japanese patients with chronic obstructive pulmonary disease, of which evidence is lacking. We conducted a cross-sectional study with a series of tests, including lung function, physical activity, symptom scores, and parameters for comorbidities. Sixty outpatients with stable disease were enrolled, and the relationship between the parameters and physical activity was evaluated. Physical activity was assessed over 7 consecutive days using a triaxial accelerometer, which records total daily energy expenditure, step count, and walking time. Cardiovascular status was assessed via echocardiography, and pulmonary artery pressure was estimated using Doppler sonography. As to mental status, depression and anxiety were assessed using the Self-Rating Depression Scale and State-Trait Anxiety Inventory, respectively. Physical activity level was significantly correlated with step count, walking time, body mass index, lean body mass index, lung function, pulmonary artery pressure, depression, anxiety, and serum total cholesterol level. In a median regression model analysis, low lung function, low lean body mass index, depression, and low serum total cholesterol level were independently associated with decreased physical activity level. These findings suggest that physical inactivity is affected by multiple extrapulmonary factors, including skeletal muscle dysfunction, depressive symptoms, and nutritional state, in Japanese patients with chronic obstructive pulmonary disease.

The Timed Up and Go test predicts frailty in patients with COPD

The Timed Up and Go (TUG) is a global measure of mobility and has the ability to detect frail individuals. Frail patients with chronic obstructive pulmonary disease (COPD) are usually undiagnosed. We hypothesised that the TUG would identify frail patients with COPD. Frailty was assessed in 520 patients diagnosed with COPD and 150 controls using a Comprehensive Geriatric Assessment questionnaire and frailty index (FI) was derived. The TUG was used to assess physical mobility. All participants were assessed for lung function and body composition. A ROC curve was used to identify how well TUG discriminates between frail and non-frail patients with COPD. The patients with COPD and controls were similar in age, sex and BMI but the patients with COPD were more frail, mean ± SD FI 0.16 ± 0.08 than controls 0.05 ± 0.03, P < 0.001. Frail patients with COPD had a greater TUG time (11.55 ± 4.03 s) compared to non-frail patients (9.2 ± 1.6 sec), after controlling for age and lung function (F = 15.94, P < 0.001), and both were greater than the controls (8.3 ± 1.2 sec), P < 0.001. The TUG discriminated between frail and non-frail patients with COPD with an area under the curve of 72 (95% CI: 67–76), and a diagnostic odds ratio of 2.67 (95% CI:1.5–4.6), P < 0.001. The TUG showed the ability to discriminate between frail and non-frail patients with COPD, independent of age and severity of the airflow obstruction. The TUG is a simple, easy and quick measure that could be easily applied in restricted settings to screen for frailty in COPD.

Using a smartphone application maintains physical activity following pulmonary rehabilitation in patients with COPD: a randomised controlled trial

BACKGROUND

Evidence suggests that patients with COPD struggle to maintain improved physical activity (PA) after completing pulmonary rehabilitation (PR). Smartphone applications (apps) providing a comprehensive training programme have conferred healthy benefits. This study was conducted to determine whether regular usage of an app maintains PA following PR.

METHODS

Patients with stage II-IV COPD were enrolled in a 6-month trial following PR. After the screening period, participants were randomised into the Kaia COPD app group (intervention group (IG)) or the control group (CG). The primary outcome was PA (daily steps), measured using an activity tracker. Secondary outcomes included the COPD Assessment Test (CAT), the Chronic Respiratory Disease Questionnaire (CRQ) and the 1 min Sit-to-Stand Test (STST).

RESULTS

Sixty participants completed the study. The median steps from baseline to 6 months were significantly different between the groups, in favour of the IG (-105.3, IQR -1970.1 to 2105.8, vs CG -1173.0, IQR -3813.1 to -93.8; p=0.007). CAT was significantly decreased in the IG (15.1±8.6 vs 19.7±6.4, p=0.02), whereas the CRQ subdomains for dyspnoea (4.5±1.7 vs 3.7±1.3, p=0.033) and fatigue (4.5±1.4 vs 3.5±1.3, p=0.028) improved significantly in the IG. The STST at 6 months was not significant. Sleep duration and sleep efficiency showed no significant differences between the two groups at any time.

CONCLUSIONS

A comprehensive program by using the Kaia app following PR maintained PA and improved symptoms in patients with COPD at 6 months. The app might be an important accessory tool for enhanced COPD care.

TRIAL REGISTRATION NUMBER

DRKS00017275.

Comparison of the Impact of Conventional and Web-Based Pulmonary Rehabilitation on Physical Activity in Patients With Chronic Obstructive Pulmonary Disease: Exploratory Feasibility Study

Background

Pulmonary Rehabilitation (PR) increases exercise capacity, with less clear evidence regarding physical activity (PA). The World Health Organization recommends at least 150-300 minutes of moderate-intensity or 75-150 minutes of vigorous-intensity aerobic PA per week to reduce the risks of chronic disease.

Objective

The objective of this study was to assess the effectiveness of conventional PR versus web-based PR with respect to changes in PA.

Methods

Patients with COPD were randomized to either conventional PR classes (n=51) or a web-based PR program (n=52) for 7 weeks in a feasibility study. Accelerometers (Sensewear) were worn before and after the intervention, and PA was measured as steps per day and mean bouts of moderate activity for ≥2, ≥5, ≥10, and ≥20 minutes. Measures were derived for patients with ≥8 hours of data per day for ≥4 days, using the R package for statistical analysis. Variables were explored to examine their relationships with bouts of activity.

Results

Baseline characteristics did not differ significantly between groups. Complete PA data were available for the groups receiving web-based (n=20) and conventional (n=34) PR interventions. The web-based PR group demonstrated a nonsignificant increase in the number of steps per day, which mainly comprised short bouts of moderate to vigorous intensity PA when compared to the conventional PR group (P=.20). The conventional PR group demonstrated increased 20-minute bouts of PA by 49.1%, although this was not significant (P=.07). At baseline, age (r=–0.21, P=.04), BMI (r=–0.311, P=.004), and FEV₁ (forced expiratory volume in 1 second; % predicted; r=–0.248, P=.048) were significantly correlated with 10-minute bouts of PA; however, this was not observed post intervention.

Conclusions

The analysis revealed a nonsignificant difference in the pattern of PA between groups receiving conventional vs web-based PR—the former being associated with an increase in 20-minute bouts, while the latter having demonstrated an increase in the number of steps per day. There appears to be a differing response emerging between the two interventions.

Trial Registration

International Clinical Trials Registry ISRCTN03142263; https://tinyurl.com/y4dmfyrb