Sedentary Behaviour and Physical Inactivity in Patients with Chronic Obstructive Pulmonary Disease: Two Sides of the Same Coin?

Association of physical activity level and all-cause mortality among stroke survivors: evidence from NHANES 2007-2018

BACKGROUND

Post-stroke disability diminishes the physical activity (PA) level of survivors, potentially affecting their long-term prognosis. This study endeavors to explore the correlation between daily PA level and the all-cause mortality in patients with a history of stoke in the United States.

METHODS

Data of stroke survivors were sourced from the National Health and Nutritional Examination Survey (NHANES) 2007-2018. The population was stratified into three groups based on their PA level. Kaplan-Meier method with log-rank tests for significance was used for survival analysis. Weighted Cox proportional hazards regression models were employed to estimate the hazard ratios (HRs) for all-cause mortality. Subgroup analysis was conducted to strengthen the results.

RESULTS

A total of 1395 participants were recruited, comprising 679 males and 716 females, with a median age of 68 years. Based on their PA levels, 779 individuals were classified as inactive, 156 as insufficiently active, and 460 as sufficiently active. Following a median observation period of 59 months, there were 476 recorded deaths, with 349, 47, and 80 cases in the three respective groups. Compared to the inactive group, the HRs and 95% confidence intervals (CIs) for all-cause mortality in participants who were insufficiently active and sufficiently active were 0.58 (0.40, 0.84) and 0.47 (0.33, 0.67), respectively. The Kaplan-Meier curve revealed a significant difference in overall survival between the three groups, as confirmed by the log-rank test (P < 0.0001). Subgroup analysis further validated our results and demonstrated that the protective impact of PA on stroke prognosis varies according to distinct characteristics.

CONCLUSIONS

The results indicate that increased levels of PA are associated with a protective effect on long-term mortality among stroke survivors. Further prospective longitudinal studies are necessary to elucidate the optional PA level and special exercise guideline targeting this population.

A behaviour change intervention to reduce sedentary behaviour in chronic obstructive pulmonary disease: a qualitative study

OBJECTIVES

To document the experiences of people with chronic obstructive pulmonary disease (COPD) who underwent a behaviour change intervention to reduce sedentary behaviour (SB) in a clinical trial.

DESIGN AND PARTICIPANTS

Qualitative study using semi-structured interviews to explore perspectives of the behaviour change intervention and specific intervention components in people with stable COPD on the waitlist for pulmonary rehabilitation.

SETTING

Three outpatient pulmonary rehabilitation programmes in Sydney, Australia.

INTERVENTIONS

The six-week behaviour change intervention with once weekly contact with a physiotherapist aimed to reduce SB by replacing it with light-intensity physical activity (PA) and by breaking up prolonged SB.

MAIN OUTCOME MEASURES

Of 30 participants who completed the behaviour change intervention, interviews were conducted with 13 participants and analysed using the 'capability, opportunity, motivation, behaviour (COM-B)' framework of behaviour change.

RESULTS

Intervention components regarded as most helpful by participants were verbal education on health consequences on SB, goal setting, and self-monitoring of, and feedback on, step count using activity trackers. There was a clear preference during goal setting to increase PA rather than to reduce SB. Physical limitations and enjoyment of SB were the most reported barriers to reducing SB.

CONCLUSIONS

Goal setting, verbal education, and self-monitoring of, and feedback on step count, were viewed positively by people with COPD and may show promise for reducing SB and increasing PA based on individual preference. CONTRIBUTION OF THE PAPER.

Physical Activity and Sedentary Behavior as Treatable Traits for Clinical Control in Moderate-to-Severe Asthma

BACKGROUND

Physical activity and sedentary behavior are treatable traits that may impact asthma control in distinct manners, but this impact remains poorly understood.

OBJECTIVE

To evaluate the influence of physical activity and sedentary behavior on clinical control in adults with moderate-to-severe asthma.

METHODS

This cross-sectional, multicentric study included 426 individuals with moderate-to-severe asthma. Assessments included physical activity and sedentary time (actigraphy), clinical asthma control (Asthma Control Questionnaire [ACQ]), quality of life (Asthma Quality of Life Questionnaire), anxiety and depression symptoms (Hospital Anxiety and Depression Scale), anthropometric data, and lung function. Participants were grouped according to physical activity levels and sedentary behavior.

RESULTS

Participants who walked ≥7500 steps/day presented better ACQ scores than those who walked <7500 steps/day (P < .05), independent of sedentary status. The percentage of patients with controlled asthma was higher in the active/sedentary (43.9%) and active/nonsedentary (43.8%) groups than in the inactive/sedentary (25.4%) and inactive/nonsedentary (23.9%) groups (P < .02). The likelihood of having uncontrolled asthma according to the treatable traits of physical inactivity (odds ratio [95% confidence interval]: 2.36 [1.55-3.59]), higher anxiety (2.26 [1.49-3.42]), and depression symptoms (1.95 [1.28-2.95]) was significant (P ≤ .002). Obesity and sedentary time were not associated with asthma control.

CONCLUSIONS

Our results show that ≥7500 steps/day is associated with better asthma control independent of sedentary time in adults with moderate-to-severe asthma. Physical inactivity, anxiety, and depression symptoms are associated with higher odds of uncontrolled asthma. These results suggest that interventions should mainly focus on increasing physical activity rather than reducing sedentary time.

Unravelling the complex interplay of factors behind exercise limitations and physical inactivity in COPD

Exercise limitation and physical inactivity are known treatable traits for people with COPD. Maximising exercise capacity and keeping people physically active improves health status and survival rates among people with COPD. However, managing these two treatable traits can be extremely challenging for clinicians due to the complex intersectionality of factors influencing an individual's capacity, opportunity and motivation to engage in physical activity. This review presents the complex factors influencing exercise capacity ("can do"), levels of physical activity ("do do") and sedentary behaviours amongst people with COPD and provides practical recommendations on how clinicians can address some of these factors in practice. Most importantly, it highlights the importance of referring to pulmonary rehabilitation as a way to improve exercise capacity among people with COPD.

Device-assessed physical activity and sleep quality of post-COVID patients undergoing a rehabilitation program

BACKGROUND

An infection with SARS-CoV-2 can lead to persistent symptoms more than three months after the acute infection and has also an impact on patients' physical activity behaviour and sleep quality. There is evidence, that inpatient post-COVID rehabilitation can improve physical capacity and mental health impairments, but less is known about the change in physical behaviour and sleep quality.

METHODS

This longitudinal observational study used accelerometery to assess the level of physical activity and sleep quality before and after an inpatient rehabilitation program. The study sample consists of 100 post-COVID patients who acquired COVID-19 in the workplace. Group differences related to sex, age, COVID-19 severity, and pre-existing diseases were also analysed.

RESULTS

Level of physical activity and sleep quality didn't increase after rehabilitation. Overall, there is a high extent of inactivity time and poor sleep quality at both measurement points. Regarding group differences, male patients showed a significantly higher inactivity time before rehabilitation, and younger patients (< 55 years) spend significant more time in vigorous physical activity than older patients. Post-COVID patients with pre-existing cardiovascular, respiratory, and metabolic disease show slightly less physical activity than post-COVID patients without these comorbidities. Female patients and younger patients showed better sleep quality in some sleep parameters at both measurement points. However, no differences could be detected related to COVID-19 severity.

CONCLUSIONS

Ongoing strategies should be implemented to address the high amount of inactivity time and the poor sleep quality in post-COVID patients.

Influencing factors of sedentary behaviour in people with chronic obstructive pulmonary disease: a systematic review

BACKGROUND

People with chronic obstructive pulmonary disease (COPD) are more likely to adopt a sedentary lifestyle. Increased sedentary behaviour is associated with adverse health consequences and reduced life expectancy.

AIM

This mixed-methods systematic review aimed to report the factors contributing to sedentary behaviour in people with COPD.

METHODS

A systematic search of electronic databases (Medline, CINAHL, PsycINFO and Cochrane Library) was conducted and supported by a clinician librarian in March 2023. Papers were identified and screened by two independent researchers against the inclusion and exclusion criteria, followed by data extraction and analysis of quality. Quantitative and qualitative data synthesis was performed.

RESULTS

1037 records were identified, 29 studies were included (26 quantitative and 3 qualitative studies) and most studies were conducted in high-income countries. The most common influencers of sedentary behaviour were associated with disease severity, dyspnoea, comorbidities, exercise capacity, use of supplemental oxygen and walking aids, and environmental factors. In-depth findings from qualitative studies included a lack of knowledge, self-perception and motivation. However, sedentarism in some was also a conscious approach, enabling enjoyment when participating in hobbies or activities.

CONCLUSIONS

Influencers of sedentary behaviour in people living with COPD are multifactorial. Identifying and understanding these factors should inform the design of future interventions and guidelines. A tailored, multimodal approach could have the potential to address sedentary behaviour.

PROSPERO REGISTRATION NUMBER

CRD42023387335.

Changes in physical activity, sedentary behaviour and sleep following pulmonary rehabilitation: a systematic review and network meta-analysis

BACKGROUND

The variety of innovations to traditional centre-based pulmonary rehabilitation (CBPR), including different modes of delivery and adjuncts, are likely to lead to differential responses in physical activity, sedentary behaviour and sleep.

OBJECTIVES

To examine the relative effectiveness of different pulmonary rehabilitation-based interventions on physical activity, sedentary behaviour and sleep.

METHODS

Randomised trials in chronic respiratory disease involving pulmonary rehabilitation-based interventions were systematically searched for. Network meta-analyses compared interventions for changes in physical activity, sedentary behaviour and sleep in COPD.

RESULTS

46 studies were included, and analyses were performed on most common outcomes: steps per day (k=24), time spent in moderate-to-vigorous physical activity (MVPA; k=12) and sedentary time (k=8). There were insufficient data on sleep outcomes (k=3). CBPR resulted in greater steps per day and MVPA and reduced sedentary time compared to usual care. CBPR+physical activity promotion resulted in greater increases in steps per day compared to both usual care and CBPR, with greater increases in MVPA and reductions in sedentary time compared to usual care, but not CBPR. Home-based pulmonary rehabilitation resulted in greater increases in steps per day and decreases in sedentary time compared to usual care. Compared to usual care, CBPR+physical activity promotion was the only intervention where the lower 95% confidence interval for steps per day surpassed the minimal important difference. No pulmonary rehabilitation-related intervention resulted in greater increases in MVPA or reductions in sedentary time compared to CBPR.

CONCLUSION

The addition of physical activity promotion to pulmonary rehabilitation improves volume of physical activity, but not intensity, compared to CBPR. High risk of bias and low certainty of evidence suggests that these results should be viewed with caution.

Physical activity level and sedentary behavior in patients with bronchiectasis: A systematic review of outcome measures and determinants

BACKGROUND

Changes in respiratory functions negatively affect the physical activity (PA) levels of patients with bronchiectasis. Therefore, detecting the most frequently used assessments of PA is essential as determining related factors and improving PA. This review study aimed to investigate the PA levels, compare levels with the recommended PA guidelines, determine the outcome measurements of PA and examine the determinants related to PA in patients with bronchiectasis.

METHOD

This review was conducted using databases of MEDLINE, Web of Science, and PEDro. The searched terms were the variations of the words "bronchiectasis" and "physical activity". Full texts of cross-sectional studies and clinical trials were included. Two authors independently screened the studies for inclusion.

RESULT

The initial search identified 494 studies. A hundred articles were selected for full-text review. Following the application of the eligibility process, 15 articles were included. Twelve studies used activity monitors and five studies used questionnaires. The studies that used activity monitors presented daily step counts. The mean number of steps ranged between 4657 and 9164 for adult patients. It was approximately 5350 steps/day in older patients. One study investigated children's PA level reported 8229 steps/day. The functional exercise capacity, dyspnea, FEV1 and, quality of life as related determinants with PA have been reported in the studies.

CONCLUSION

PA levels of patients with non-cystic fibrosis bronchiectasis were lower than the recommended levels. The objective measurements were frequently used in PA assessment. In further studies, it is needed to investigate the related determinants of PA in patients.

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.

Prolonged bouts of sedentary behavior in people with chronic obstructive pulmonary disease and associated factors

BACKGROUND

Increased sedentary behavior (SB), especially in prolonged bouts, is associated with adverse health outcomes, but little is known about patterns of SB in people with chronic obstructive pulmonary disease (COPD).

OBJECTIVES

The purpose of this study was to describe SB and patterns of SB and to examine factors associated with prolonged bouts of SB in inactive community-dwelling adults with COPD.

METHODS

This cross-sectional analysis used data from inactive adults with COPD who were enrolled in an exercise program but had not started exercising. Participants were ≥ 50 years old with a diagnosis of COPD, had a forced expiratory volume in one second < 80% predicted, and were inactive. Participants wore an activPAL device for seven days to measure their SB and completed surveys and physical measures. Data were analyzed with multiple regression.

RESULTS

The sample included 160 participants with a mean age (± SD) of 69 ± 8, and a mean total sedentary time of 742 ± 150 min/day, with 254 ± 146 min/day in SB bouts ≥ 60 min.

DURATION

Time spent in bouts of SB ≥ 60-min. was negatively associated with self-efficacy for overcoming barriers to light physical activity (P<0.05), balance (P<0.05), chair stand test (P<0.05), FEV1% predicted (P<0.05) and positively associated with BMI (P<0.001).

CONCLUSIONS

Inactive people with COPD engage in extensive SB, much of it in prolonged bouts. Self-efficacy, balance, and lower body strength are modifiable variables associated with SB and potential targets for future interventions to reduce time in prolonged sedentary behavior.

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.

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.

Breathing Control Exercises Delivered in a Group Setting for Patients with Chronic Obstructive Pulmonary Disease: A Randomized Controlled Trial

Breathing control exercises are an important component of occupational therapy in patients with chronic obstructive pulmonary disease (COPD). Delivering these exercises in group settings may enhance their benefits. Therefore, this study assessed the effectiveness of breathing control exercises delivered in a group format to patients with severe COPD remitting from an acute pulmonary exacerbation. This randomized controlled trial of 6 weeks’ duration compared the addition of breathing exercise sessions delivered in a group setting to a standard exercise inpatient rehabilitation program (usual care) versus usual care alone. The standard exercise program consisted of endurance and strength training and therapeutic patient education. The intervention group received, in addition to usual care, 20 sessions of 30 min duration of breathing control exercises in a group setting. The primary outcome was quality of life (Saint George’s Respiratory Questionnaire). Secondary outcomes were the COPD assessment test, modified Borg scale, handgrip strength test, and five-time sit-to-stand test. Thirty-seven patients aged 69 ± 7 years were recruited. After the 6-week period, all outcomes significantly improved and exceeded the minimal clinically important difference in the intervention group only. Between-group changes were significant for each outcome. Conclusions: breathing control exercises in a group setting provide clinically relevant benefits in patients with severe COPD who are remitting from an acute pulmonary exacerbation.

Validity and Accuracy of Step Count as an Indicator of a Sedentary Lifestyle in People With Chronic Obstructive Pulmonary Disease

OBJECTIVE

To determine the validity and accuracy of <5000 steps/day as a sedentary lifestyle indicator, and the optimal step count cut point value for indicating a sedentary lifestyle in people with chronic obstructive pulmonary disease (COPD).

DESIGN

Analysis of baseline data from a randomized clinical trial.

SETTING

Sydney, Australia.

PARTICIPANTS

Stable COPD on the waitlist for pulmonary rehabilitation.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Step count and time in sedentary behavior (SB) were assessed using thigh-worn accelerometry. A sedentary lifestyle was defined as <5000 steps/day. Pearson correlation coefficients were analyzed between step count and time spent in SB. Sensitivity, specificity, and accuracy were calculated for the <5000 steps/day threshold. Receiver operating characteristic curves with the area under the curve were computed for step count in identifying a sedentary lifestyle.

RESULTS

69 people with COPD (mean age=74 years, SD=9; forced expiratory volume in 1 second, mean=55%, SD=19 predicted) had sufficient wear data for analysis. There was a moderate inverse correlation between step count and time spent in SB (r=-0.58, P<.001). Step count had a fair discriminative ability for identifying a sedentary lifestyle (area under the curve=0.80, 95% confidence interval [CI], 0.68-0.91). The <5000 steps/day threshold had a sensitivity, specificity, and accuracy of 82% (95% CI, 70-94), 70% (95% CI, 54-86), and 78%, respectively. A lower threshold of <4300 steps/day was more accurate for ruling in a sedentary lifestyle.

CONCLUSIONS

Compared with thigh-worn accelerometry, <5000 steps/day is a valid and reasonably accurate indicator of a sedentary lifestyle in this population.

Physical activity promotion interventions in chronic airways disease: a systematic review and meta-analysis

Physical inactivity is common in people with chronic airways disease (pwCAD) and associated with worse clinical outcomes and impaired quality of life. We conducted a systematic review and meta-analysis to characterise and evaluate the effectiveness of interventions promoting step-based physical activity (PA) in pwCAD. We searched for studies that included a form of PA promotion and step-count outcome measure. A random-effects model was used to determine the overall effect size using post-intervention values. 38 studies (n=32 COPD; n=5 asthma; n=1 bronchiectasis; study population: n=3777) were included. Overall, implementing a form of PA promotion resulted in a significant increase in step-count: median (IQR) 705 (183-1210) when compared with usual standard care: -64 (-597-229), standardised mean difference (SMD) 0.24 (95% CI: 0.12-0.36), p<0.01. To explore the impact of specific interventions, studies were stratified into subgroups: PA promotion+wearable activity monitor-based interventions (n=17) (SMD 0.37, p<0.01); PA promotion+step-count as an outcome measure (n=9) (SMD 0.18, p=0.09); technology-based interventions (n=12) (SMD 0.16, p=0.01). Interventions promoting PA, particularly those that incorporate wearable activity monitors, result in a significant and clinically meaningful improvement in daily step-count in pwCAD.

LABA/LAMA as First-Line Therapy for COPD: A Summary of the Evidence and Guideline Recommendations

Inhaled bronchodilators (alone or in combination) are the cornerstone of treatment for symptomatic patients with COPD, either as initial/first-line treatment or for second-line/treatment escalation in patients who experience persistent symptoms or exacerbations on monotherapy. The Global Initiative for Chronic Obstructive Lung Disease 2022 report recommends initial pharmacological treatment with a long-acting muscarinic antagonist (LAMA) or a long-acting β₂-agonist (LABA) as monotherapy for most patients, or dual bronchodilator therapy (LABA/LAMA) in patients with more severe symptoms, regardless of exacerbation history. The recommendations for LABA/LAMA are broader in the American Thoracic Society treatment guidelines, which strongly recommend LABA/LAMA combination therapy over LAMA or LABA monotherapy in patients with COPD and dyspnea or exercise intolerance. However, despite consistent guideline recommendations, real-world prescribing data indicate that LAMA and/or LABA without an inhaled corticosteroid are not the most widely prescribed therapies in COPD. This article reviews global and regional/national guideline recommendations for the use of LABA/LAMA in COPD, examines the evidence for the effectiveness and safety of LABA/LAMA versus other therapies and offers a practical guide for clinicians to help ensure appropriate use of LABA/LAMA therapy.

Quantifying the Effect of Monitor Wear Time and Monitor Type on the Estimate of Sedentary Time in People with COPD: Systematic Review and Meta-Analysis

In studies that have reported device-based measures of sedentary time (ST) in people with chronic obstructive pulmonary disease (COPD), we explored if the monitor type and monitor wear time moderated the estimate of this measure. Five electronic databases were searched in January 2021. Studies were included if >70% of participants had stable COPD, and measures of ST (min/day) were collected using wearable technology. Meta-regression was used to examine the influence of moderators on ST, monitor type, and wear time. The studies identified were a total of 1153, and 36 had usable data for meta-analyses. The overall pooled estimate of ST (mean [95% CI]) was 524 min/day [482 to 566] with moderate heterogeneity among effect sizes (I2 = 42%). Monitor wear time, as well as the interaction of monitor wear time and monitor type, were moderators of ST (p < 0.001). The largest difference (−318 min; 95% CI [−212 to −424]) was seen between studies where participants wore a device without a thigh inclinometer for 24 h (and removed sleep during analysis) (675 min, 95% CI [589 to 752]) and studies where participants wore a device with a thigh inclinometer for 12 h only (356 min; 95% CI [284 to 430]). In people with COPD, the monitor wear time and the interaction of the monitor wear time and the monitor type moderated the estimate of ST.

A machine learning approach to predict extreme inactivity in COPD patients using non-activity-related clinical data

Facilitating the identification of extreme inactivity (EI) has the potential to improve morbidity and mortality in COPD patients. Apart from patients with obvious EI, the identification of a such behavior during a real-life consultation is unreliable. We therefore describe a machine learning algorithm to screen for EI, as actimetry measurements are difficult to implement. Complete datasets for 1409 COPD patients were obtained from COLIBRI-COPD, a database of clinicopathological data submitted by French pulmonologists. Patient- and pulmonologist-reported estimates of PA quantity (daily walking time) and intensity (domestic, recreational, or fitness-directed) were first used to assign patients to one of four PA groups (extremely inactive [EI], overtly active [OA], intermediate [INT], inconclusive [INC]). The algorithm was developed by (i) using data from 80% of patients in the EI and OA groups to identify ‘phenotype signatures’ of non-PA-related clinical variables most closely associated with EI or OA; (ii) testing its predictive validity using data from the remaining 20% of EI and OA patients; and (iii) applying the algorithm to identify EI patients in the INT and INC groups. The algorithm’s overall error for predicting EI status among EI and OA patients was 13.7%, with an area under the receiver operating characteristic curve of 0.84 (95% confidence intervals: 0.75–0.92). Of the 577 patients in the INT/INC groups, 306 (53%) were reclassified as EI by the algorithm. Patient- and physician- reported estimation may underestimate EI in a large proportion of COPD patients. This algorithm may assist physicians in identifying patients in urgent need of interventions to promote PA.

Individualized, low-cost and accessible pulmonary rehabilitation program based on functional clinical tests for individuals with COPD-a study protocol of a randomized controlled trial

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) present pulmonary and extrapulmonary impairments. The strategies used to mitigate these impairments are pulmonary rehabilitation programs (PRP). However, there is limited access to PRP in specialized centers and the study of low-cost home rehabilitation programs had non-individualized prescription, which might have led to insignificant positive effects. So, it is important to develop new low-cost protocols that involve individualized prescription, as well as physiotherapist supervision. This study describes an accessible, low-cost, and individualized pulmonary rehabilitation protocol and compare its results when performed with or without a weekly physiotherapist-supervised session on patients with COPD.

METHODS

This is a descriptive protocol of a clinical trial, randomized, single-blinded, and type of framework is superiority conducted at the Spirometry and Respiratory Physical Therapy Laboratory of the Federal University of São Carlos (UFSCar). The trial is registered in the Brazilian Clinical Trials Registry (ReBec) URL: http://www.ensaiosclinicos.gov.br/rg/RBR-533hht/ with Register Number UTN code U1111-1220-8245. The sample size is 50 patients and is calculated using the results of a pilot study.

DISCUSSION-POTENTIAL IMPACT AND SIGNIFICANCE OF THE STUDY

It is expected that the low-cost and new supervised rehabilitation program complemented with home exercises will present positive results, especially on exercise capacity, which will make available a more accessible and effective PRP for patients with COPD.

TRIAL REGISTRATION

ClinicalTrials.gov U1111-1220-8245 . Registered on September 20, 2018.

Sedentary time in people with obstructive airway diseases

Sedentary time (ST) and light-intensity physical activity (LIPA) are movement behaviours associated with important health outcomes, but are not widely explored in respiratory diseases. We aimed to describe their volume and/or accumulation patterns in moderate-severe COPD, bronchiectasis and severe asthma using the accurate postural-based accelerometer activPAL, contrasting these values with a non-respiratory population. We also sought to test the cross-sectional associations of these behaviours with disease characteristics by diagnostic group, and as a combined label-free disease group.

RESULTS

Adults with COPD (n = 64), bronchiectasis (n = 61), severe asthma (n = 27), and controls (n = 61) underwent cross-sectional measurements of volume and/or accumulation patterns of ST and LIPA. The prevalence and characteristics, and associations with exercise capacity, health-status, airflow-limitation, dyspnoea, systemic inflammation and exacerbations were analysed. ST volumes in COPD were higher than that of bronchiectasis and severe asthma. Values in bronchiectasis and severe asthma were similar to each other and controls (≈8.9 h/day). Their accumulation patterns were also significantly better than in COPD, but similar if not worse compared to controls. LIPA volumes in bronchiectasis and severe asthma were also higher than those of COPD (p < 0.05) and controls. In bronchiectasis and COPD, lower levels/better patterns of ST accumulation, as well as higher LIPA volume were associated with better clinical characteristics. These associations may be mediated by airflow limitation.

CONCLUSIONS

The discordance between engagement in ST volume versus ST patterns highlights the importance of accounting for both these different yet complementary metrics. ST and LIPA are low-intensity activities associated with important clinical characteristics in people with chronic respiratory diseases.

TRIAL REGISTRATION

Not applicable.

Exacerbations and Changes in Physical Activity and Sedentary Behaviour in Patients with Bronchiectasis after 1 Year

Background: Low physical activity and high sedentary behaviour in patients with bronchiectasis are associated with hospitalisation over one year. However, the factors associated with longitudinal changes in physical activity and sedentary behaviour have not been explored. We aimed to identify clinical and sociodemographic characteristics related to a change in physical activity and sedentary behaviour in patients with bronchiectasis after one year. Methods: This was a prospective observational study during which physical activity measurements were recorded using a SenseWear Armband for one week at baseline and at one year. At each assessment point, patients were classified as active or inactive (measured as steps per day) and as sedentary or not sedentary (measured as sedentary time). Results: 53 patients with bronchiectasis were analysed, and after one year, 18 (34%) had worse activity and sedentary levels. Specifically, 10 patients became inactive and sedentary. Multivariable analysis showed that the number of exacerbations during the follow-up period was the only outcome independently associated with change to higher inactivity and sedentary behaviour (odds ratio (OR), 2.19; 95% CI, 1.12 to 4.28). Conclusions: The number of exacerbations in patients with bronchiectasis was associated with changes in physical activity and sedentary behaviour. Exacerbation prevention may appear as a key factor in relation to physical activity and sedentary behaviour in patients with bronchiectasis.

Energy expenditure per minute in different activities and body positions and its association with the classification as physically active or inactive in daily life in individuals with COPD

Objective: To describe and compare energy expenditure (EE)/minute walking and in different body postures in individuals with COPD; and to investigate if EE/minute walking is a predictor of their classification as physically active or inactive. Methods: Physical activity (PA) in daily life was objectively assessed using two PA monitors for 7 days and data were analyzed on a minute-by-minute basis. Predominant minutes were separated into walking, standing, sitting, and reclined, and EE/minute (a reflection of PA intensity) was then calculated in each of these four activities and postures. Participants were classified as active and inactive according to the criteria proposed by the American College of Sports Medicine (ACSM). Results: 43 individuals were evaluated (65±8 years; FEV1 50±14% predicted). A binary logistic regression model yielded that, regardless of the time spent walking/day, EE/minute walking was a significant predictor of the classification as physically active (OR=18.2 [2 - 165]; p=0.01), together with BMI (OR=0.68 [0.5 - 0.9]; p=0.008) (model: Chi-square = 22.431, p< 0.05; R2 [Nagelkerke] = 0.556). In the active group, significantly higher EE/minute was observed for walking and standing in comparison both to sitting and reclined. However, in the inactive group, there were significant differences in EE/minute only when comparing walking versus reclined and standing versus reclined. Conclusion: In individuals, with COPD, EE/minute walking is a significant predictor of being classified as physically active, independently of the time spent walking/day. Each additional kilocalorie/minute spent walking increases in 18 times the chances to be classified as physically active in daily life.

Portable Oxygen Therapy: Is the 6-Minute Walking Test Overestimating the Actual Oxygen Needs?

The appropriate titration for the personalized oxygen needs of patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia is a determining factor in the success of long-term oxygen therapy. There are no standardized procedures to assist in determining the patient’s needs during the physical activities of daily life. Despite that effort tests are a wide broad approach, further research concerning the development of protocols to titrate O₂ therapy is needed. The main objective of this study was to assess whether the level of oxygen titrated through the 6-minute walking test (6MWT) for patients with COPD and exertional hypoxemia is adequate to meet the patients’ demand during their activities of daily living. Physiological and subjective variables were estimated for a study population during two walking tests: a 6MWT and a 20-minute walking circuit (20MWC), designed ad-hoc to reproduce daily physical activities more truthfully. The results indicate that in a significant proportion of patients, the 6MWT might not accurately predict their oxygen needs at a domiciliary environment. Therefore, the titration of the portable O₂ therapy could not be optimal in these cases, with the detrimental impact on the patient’s health (hyperoxia episodes), the autonomy of the oxygen device, and the decrease of time out of the home.

Tossing and turning: association of sleep quantity-quality with physical activity in COPD

The association between characteristics of sleep and physical activity in daily life (PADL) has not yet been investigated in depth in subjects with COPD. This study evaluated whether time spent per day in physical activity (PA) and sedentary behaviour are associated with sleep quantity and quality in this population. Sleep and PADL were objectively assessed by an activity monitor for 7 days and analysed on a minute-by-minute basis. Subjects also underwent spirometry and 6-min walking test (6MWT). Fifty-five subjects with moderate-to-severe COPD (28 male, 67±8 years) were studied. Subjects with total time in bed (TIB) per night ≥9 h had higher wake-after-sleep onset than TIB 7-9 h and TIB ≤7 h (195 (147-218) versus 117 (75-167) and 106 (84-156) min) and more fragmented sleep than TIB ≤7 h (8.2 (6.7-14.3) versus 6.3 (5.6-6.9) sleeping bouts; p<0.05 for all). Subjects with TIB ≥9 h also spent more time per day in sedentary behaviour and less time per day in PA of light and moderate-to-vigorous intensity than those with TIB 7-9 h and ≤7 h. In multiple linear regression, TIB ≥9 h was the only significant predictor of physical inactivity (β=-3.3 (-5.1, -1.6), p≤0.0001), accounting for 20% of its variation. Sleep fragmentation was frequent and more pronounced in physically inactive than active patients (7.5 (6.3-9.6) versus 6.4 (5.5-7.3) sleeping bouts; p=0.027). In summary, subjects with COPD with TIB ≥9 h·night-1 have more fragmented sleep, are more sedentary and less physically active than those with <9 h·night-1, independently of the awake time. Sleep quality is frequently poor and even worse in patients classified as physically inactive.

Determinants of Sedentary Behaviour in Individuals with COPD: A Qualitative Exploration Guided by the Theoretical Domains Framework

In people with chronic obstructive pulmonary disease (COPD), there is increasing recognition that the prolonged accumulation of sedentary time (ST) is associated with adverse cardio-metabolic health outcomes. Nevertheless, changing this lifestyle, which has evolved over several decades, is likely to be challenging. This study reports the determinants, perceived by individuals with COPD, as being important for reducing ST. An in-depth understanding of this information is essential when planning an intervention to reduce ST. Fourteen individuals with COPD completed semi-structured one-on-one interviews, which were audio recorded and transcribed verbatim. Both the interview schedule and mapping of data items extracted from the interview transcripts were informed by the Theoretical Domains Framework (TDF). A total of 867 quotes were mapped to the 14 TDF domains. Seven of the fourteen domains were identified as being important determinants for reducing ST: knowledge, beliefs about consequences, beliefs about capabilities, environmental context and resources, social influences, social/professional role and identity, and behavioural regulation. There was a lack of knowledge regarding the meaning of sedentary behaviour. Participants' desire to be educated by knowledgeable health professionals in a formal programme was a dominant theme across multiple domains. The most frequently reported barriers to reducing ST related to the domains of social/professional role and identity and environmental context and resources, while the most frequently reported enablers were related to the domains pertaining to beliefs about consequences and social influences. Potential strategies to reduce ST among people with COPD include education and other determinants identified in this research.