Physical Activity In Chronic Obstructive Pulmonary Disease Research Articles

Effects of Daily Physical Activity on Exercise Capacity in Chronic Obstructive Pulmonary Disease

Background and Objectives: In adults, 150 to 300 min a week of moderate-intensity physical activity is the recommended daily level to maintain or improve fitness. In subjects with chronic obstructive pulmonary disease (COPD), reductions in daily physical activity (DPA) amounts are related to clinically significant outcomes. In this study, we ascertain whether or not COPD patients, when clustered into active (DPA ≥ 30 min a day, 5 days a week) and inactive (DPA < 30 min a day, 5 days a week), may differ in exercise capacity, as assessed by a cardiopulmonary exercise test (CPET). Materials and Methods: A large sample of clinically stable COPD patients was retrospectively recruited and then underwent spirometry and an incremental ramp protocol 5–15 watts/min CPET. DPA was assessed by a questionnaire. Results: A total of 83 (female 25%, age range 41–85 y) active and 131 (female 31%, age range 49–83 y) inactive participants were enrolled. They were similar in age, sex distribution, body mass index (BMI) and in spirometry. The two groups were significantly different in dyspnea on exertion, as assessed by the modified Medical Research Council (mMRC), and in cardio-metabolic parameters, but not in ventilatory ones, as confirmed by the CPET. Conclusions: COPD patients experiencing physical activity of at least 30 min a day, 5 days a week, showed a greater exercise capacity and an improved cardiovascular response to exercise, when compared to inactive ones. Active and inactive participants did not differ in terms of airflow obstruction severity as well as in dynamic hyperinflation and ventilatory inefficiency during exercise. This study further suggests the benefits of regular physical activity in COPD.

Do Functional Tests Estimate Physical Activity in COPD?

The association between physical activity in daily life (PADL) and simple functional tests is not yet clearly understood in subjects with chronic obstructive pulmonary disease (COPD). Therefore, the aim of this study was to investigate the association of two functional tests (Sit-to-Stand test [STS] and the 4-Metre Gait Speed test [4MGS]) with PADL, as well as to identify whether these tests can discriminate those subjects who are physically inactive. In this cross-sectional study, 28 subjects with COPD performed the five repetitions Sit-to-Stand (STS5r), the 4MGS and used the DynaPort activity monitor for 7 days in order to assess PADL. Walking time, movement intensity while walking (MI) and Physical Activity Level index (PAL) were considered as PADL outcomes. STS5r and 4MGS, respectively, were significantly associated with walking time (R2 = 0.16; p = 0.024 and R2 = 0.25; p = 0.006) and PAL index (R2 = 0.17; p = 0.002 and R2 = 0.30; p = 0.003), whereas movement intensity was associated only with the 4MGS (R2 = 0.23; p = 0.009). Additionally, both tests were able to discriminate physically inactive subjects (cutoffs: STS5r = 11.48s [AUC = 0.73]; 4MGS = 1.09m/s [AUC = 0.88]). In conclusion, STS5r and 4MGS can predict up to 30% of PADL in subjects with COPD. Both tests are related to PADL duration (e.g. time spent walking), while only the 4MGS reflects movement intensity. Both tests presented discriminative capacity to identify subjects with worse PADL pattern.

Kinesiotherapy and physical activity in COPD and Asthma Patients – A Review

Background: Obstructive chronic diseases are a continuous challenge for healthcare perfusionists all over the world. Asthma and Chronic Obstructive Pulmonary Disease (COPD) are the most frequent of these diseases. Respiratory or pulmonary rehabilitation started to gain momentum and it is more frequently used to improve muscle strength, cardiac and respiratory endurance and joint flexibility. The objective of this paper is to establish the current programs of physical activity or kinesiotherapy used in the past year and to reveal if there are any gaps or mismatches in the development of the program or in the instruments used to quantify the results of the rehabilitation programs. Materials and methods: We reviewed a total number of 12 articles, randomized control trials using the search words kinesiotherapy, physical therapy, COPD and asthma from the last year on PubMed.gov, from 11 different countries in order to establish which have similar types of exercises, parameters used in order to compare results and which were the outcomes. Results: The final results are positive, although it is hard to determine a unity because there were so many different parameters used to monitor the patients. The most frequent parameter was the 6MWT used to compare the effectiveness of the physical program in 6 studies. Discussion and conclusions: This review had its limitation in comparing the 12 articles researched because of the different number of patients, the various physical activity and rehabilitation exercises used, but especially because of the many varieties of scales and scores used to monitor the effectiveness of the treatment. In order to successfully compare such papers, an international guideline is necessary to relay specific rehabilitation programs for every type of respiratory pathology and also which are the most recommended scales or scores or parameters in general to asses such rehabilitation programs. Keywords: kinesiotherapy; physical activity; physical therapy; COPD, asthma

Factors associated with physical activity among COPD patients with mild or moderate airflow obstruction.

Physical inactivity is already present among patients with chronic obstructive pulmonary disease (COPD) of mild or moderate airflow obstruction. Most previous studies that reported on determinants of physical activity in COPD included patients with severe COPD. Therefore, the aim of this study was to explore which patient characteristics were related with physical activity in COPD patients with mild or moderate airflow obstruction. Cross-sectional analyses were performed on patients selected from the population-based Netherlands Epidemiology of Obesity study. Patients were included if they had a physician-diagnosed COPD GOLD 0-2 or had newly diagnosed COPD GOLD 1-2. Physical activity was evaluated using the Short Questionnaire to Assess Health-Enhancing Physical Activity (SQUASH) questionnaire and reported in hours per week of metabolic equivalents (MET-h/week). Associations between sociodemographic, lifestyle, clinical and functional characteristics were examined using regression analysis. 323 patients were included in research (77 with physician-diagnosed and 246 with newly diagnosed COPD). We found that physical activity was positively associated with pulmonary function: FEV1 (regression coefficient 0.40 (95% CI 0.09,0.71)) and FVC (regression coefficient 0.34 (95% CI 0.06,0.61)). Physical activity was associated with anxiety (regression coefficient =0.9 (95% CI 0.3,1.6)) only for physician-diagnosed patients.Lung function and anxiety level determine level of physical activity among COPD patients with mild or moderate airflow obstruction. Thus, integrating it into the physical activity plans could help to increase physical activity level of the patients.

Isotonic quadriceps endurance is better associated with daily physical activity than quadriceps strength and power in COPD: an international multicentre cross-sectional trial

Knowledge about modifiable determinants of daily physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) is crucial to design effective PA interventions. The present study aimed to determine the contribution of quadriceps strength, power and endurance to daily PA in COPD. Additionally, for quadriceps endurance, we also aimed to determine to what extent the association varies according to the mode of movement (isotonic, isometric, or isokinetic). Using a multicentre cross-sectional trial design we determined the contribution of quadriceps function to daily PA (steps, sedentary time and time spent doing moderate-to-very-vigorous physical activity [MVPA]) using bivariate and partial Pearson correlation analysis (r) and multiple linear regression models (ΔR2). Pre-determined controlling factors were sex, age, body mass index (BMI), COPD-assessment test, forced expiratory volume in one second in percent of the predicted value (FEV1pred), and distance walked on the 6-minute walk test. Eighty-one patients with COPD (mean ± SD: age 67 ± 8 years, FEV1pred 57 ± 19%, daily steps 4968 ± 3319, daily sedentary time 1016 ± 305 min, and MVPA time 83 ± 45 min) were included. Small to moderate bivariate correlations (r = .225 to .452, p < .05) were found between quadriceps function and measures of PA. The best multiple linear regression models explained 38–49% of the variance in the data. Isotonic endurance was the only muscle contributor that improved all PA models; daily steps (ΔR2 = .04 [relative improvement 13%] p = .026), daily sedentary time (ΔR2 = .07 [23%], p = .005) and MVPA-minutes (ΔR2 = .08 [20%], p = .001). Isotonic endurance was also independently associated with most PA variables, even when controlling for strength, power or isometric-isokinetic endurance properties of the muscle (r = .246 to .384, p < .05). In contrast, neither strength, power, isometric-or isokinetic endurance properties of the muscle was independently associated with PA measures when controlling for isotonic endurance (r = .037 to .219, p > .05). To conclude, strength, power, and endurance properties of the quadriceps were low to moderately associated with PA in patients with COPD. Isotonic quadriceps endurance was the only quadriceps property that was independently associated with the different measures of PA after controlling for a basic set of known determinants of PA, quadriceps strength or power, or isometric or isokinetic quadriceps endurance. Future longitudinal studies should investigate its potential as a modifiable determinant of PA.

Barriers toward Physical Activity in COPD: A Quantitative Cross-Sectional, Questionnaire-Based Study

Chronic Obstructive Pulmonary Disease (COPD) is a progressive but preventable and treatable disease and the third leading cause of death globally. Even though it is evident that physical activity (PA) relieves dyspnea, anxiety, fatigue, and increases quality of life and functional capacity, it is seldom implemented in daily life in people with COPD. The aim of this study was to identify barriers toward PA in people with COPD and to examine the role of FEV1 and smoking status in PA. The study is a quantitative cross-sectional study conducted in Denmark among people with COPD. Data was collected using questionnaires developed by the authors after pilot testing. In total, 493 people with COPD were included. The most significant barrier toward PA was low motivation (p < 0,001 and p = 0,009) and comorbidity (p = 0,035 and p = 0,016). Fear of breathlessness was significantly (p < 0,001) correlated to low motivation. FEV1, and smoking status were not associated with the level of PA. In our study, the main reason why people with COPD did not engage in PA was low motivation, where fear of breathlessness and co-morbidity correlated significantly with low motivation. Studies have shown that doing activities that are enjoyable promotes PA in daily life, indicating that activities that enhance motivation might help people with COPD to see PA as part of their life rather than an obligation. Further exploratory studies are needed.

Development of a Novel Intervention (Mindful Steps) to Promote Long-Term Walking Behavior in Chronic Cardiopulmonary Disease: Protocol for a Randomized Controlled Trial.

BackgroundDespite current rehabilitation programs, long-term engagement in physical activity remains a significant challenge for patients with chronic obstructive pulmonary disease (COPD) and heart failure (HF). Novel strategies to promote physical activity in these populations are greatly needed. Emerging literature on the benefits of both mind–body interventions and web-based interventions provide the rationale for the development of the Mindful Steps intervention for increasing walking behavior.ObjectiveThis study aims to develop a novel multimodal mind–body exercise intervention through adaptation of an existing web-based physical activity intervention and incorporation of mind–body exercise, and to pilot test the delivery of the new intervention, Mindful Steps, in a randomized controlled feasibility trial in older adults with COPD and/or HF.MethodsIn phase 1, guided by a theoretical conceptual model and review of the literature on facilitators and barriers of physical activity in COPD and HF, we convened an expert panel of researchers, mind–body practitioners, and clinicians to inform development of the novel, multimodal intervention. In phase 2, we are conducting a pilot randomized controlled feasibility trial of the Mindful Steps intervention that includes in-person mind–body exercise classes, an educational website, online mind–body videos, and a pedometer with step-count feedback and goals to increase walking behavior in patients with COPD and/or HF. Outcomes include feasibility measures as well as patient-centered measures.ResultsThe study is currently ongoing. Phase 1 intervention development was completed in March 2019, and phase 2 data collection began in April 2019.ConclusionsThrough the integration of components from a web-based physical activity intervention and mind–body exercise, we created a novel, multimodal program to impact long-term physical activity engagement for individuals with COPD and HF. This developmental work and pilot study will provide valuable information needed to design a future clinical trial assessing efficacy of this multimodal approach.Trial RegistrationClinicalTrials.gov NCT03003780; https://clinicaltrials.gov/ct2/show/NCT03003780International Registered Report Identifier (IRRID)DERR1-10.2196/27826

Longitudinal Relationship Between Growth Differentiation Factor 11 and Physical Activity in Chronic Obstructive Pulmonary Disease.

BackgroundDaily physical activity is reduced in patients with chronic obstructive pulmonary disease (COPD) and a reduced level of physical activity has been shown to be an important predictor for the prognosis, such as increased risk of exacerbation and mortality. However, there has not yet been a useful biomarker of the physical activity. In our previous cross-sectional study, we showed that the level of one of the possible myokines, which is an anti-aging factor, growth differentiation factor 11 (GDF11), was decreased in the plasma from patients with COPD and correlated with the physical activity. To clarify this relationship, we conducted a longitudinal evaluation of such factors.Patients and MethodsTwenty-four COPD patients were enrolled and prospectively followed. We measured the levels of plasma GDF11 and systemic inflammatory markers with immunoblotting or ELISA, respectively. We also evaluated lung function and daily physical activity using a triaxial accelerometer and the incidence of exacerbation.ResultsThe change in the plasma level of GDF11, but not systemic inflammatory markers, was positively correlated with the change in the physical activity in an intensity-dependent manner (between the change in the number of steps and GDF11; r = 0.41, p = 0.047). In the multiple regression analysis, the relationship was confirmed (β = 0.93, p < 0.001). In addition, patients who maintained their plasma level of GDF11 showed a significantly lower incidence in exacerbations of COPD than those with decreased levels of GDF11 (p = 0.041).ConclusionThe longitudinal change in the plasma level of GDF11 was positively correlated with the change in the daily physical activity in COPD. GDF11 could be a useful humoral factor that reflects the physical activity in COPD.

Validity and responsiveness of the Daily- and Clinical visit-PROactive Physical Activity in COPD (D-PPAC and C-PPAC) instruments

BackgroundThe Daily-PROactive and Clinical visit-PROactive Physical Activity (D-PPAC and C-PPAC) instruments in chronic obstructive pulmonary disease (COPD) combines questionnaire with activity monitor data to measure patients’ experience of physical activity....

Reliability of the Thai version of the International Physical Activity Questionnaire Short Form in chronic obstructive pulmonary disease

ObjectiveTo determine the reliability of the Thai version of International Physical Activity Questionnaire Short Form (IPAQ-SF) in Chronic Obstructive Pulmonary Disease (COPD) patients. MethodsA cross sectional study was carried out in COPD subjects at Chiang Dao hospital, Chiang Mai, Thailand in June and July 2019. COPD subjects were asked to complete the Thai version of the IPAQ-SF. Calculations for each level of activity were carried out separately (vigorous activity, moderate activity, walking, and sitting). This was carried out twice with an interval of four weeks between visits. The test–retest reliability of the IPAQ was assessed using the intraclass correlation (ICC) with a 95% confidence interval (CI). Cohen's kappa coefficient and percentage agreement were used to test the repeatability of the physical activity classification between the two visits. ResultsSixty COPD subjects (50% male), with a mean age of 71.2 ± 7.7 years were included. The least reliability was established for sitting time (ICC = 0.439; 95%CI; 0.212, 0.621, p-value < 0.001) and the greatest for the total physical activity (ICC = 0.837; 95%CI; 0.741, 0.899, p-value < 0.001). The Kappa statistic was 0.433 with a 95%CI; 0.237, 0.639, p-value < 0.001 and the percentage agreement of the physical activity classification between the two visits was 66.7%. ConclusionThe test–retest reliability was adequate for vigorous activity and total physical activity. Although there are concerns about the agreement for classification of physical activity, the IPAQ-SF may be a useful if not definitive tool for assessing physical activity in COPD.

Physical activity in COPD: Minimal clinically important difference for medical events.

Estimates of the minimal clinically important difference (MCID) for physical activity (PA) in chronic obstructive pulmonary disease (COPD) are needed. The objective is to provide an anchor-based estimate of the MCID for daily step count. PA was promoted in persons with COPD using a pedometer (Omron HJ-720ITC) alone or a pedometer plus interactive website for 3 months. Participants wore the pedometer daily and received phone calls monthly to ascertain medical events. Medical events were counted when a participant self-reported that he/she had (1) worsening of breathing, (2) change to breathing medications, (3) medical care from an emergency room for any reason, or (4) hospitalization for any reason. Generalized linear regression models assessed daily step count as change at the end of study and averaged over the 15, 31, or 61 days centered on the event, in those with an event compared to those without one. All categories of events carried equal weight in the analyses. We studied 93 persons, 46 of whom had an event. Participants who experienced an event had a decrease of 1086 (95% confidence interval (CI): −2124 to −48) or 887 (95% CI: −2030 to 257) steps/day in the pedometer plus website or pedometer alone groups, respectively, compared to those without one. In the days centered on an event, participants who had an event experienced a decrease of 882–983 steps/day (pedometer plus website) or a decrease of 351–495 steps/day (pedometer alone), compared to those without one. The MCID for PA in COPD ranges from 350 steps/day to 1100 steps/day.

Long-term efficacy and effectiveness of a behavioural and community-based exercise intervention (Urban Training) to increase physical activity in patients with COPD: a randomised controlled trial.

There is a need to increase and maintain physical activity in patients with chronic obstructive pulmonary disease (COPD). We assessed 12-month efficacy and effectiveness of the Urban Training intervention on physical activity in COPD patients.This randomised controlled trial (NCT01897298) allocated 407 COPD patients from primary and hospital settings 1:1 to usual care (n=205) or Urban Training (n=202). Urban Training consisted of a baseline motivational interview, advice to walk on urban trails designed for COPD patients in outdoor public spaces and other optional components for feedback, motivation, information and support (pedometer, calendar, physical activity brochure, website, phone text messages, walking groups and a phone number). The primary outcome was 12-month change in steps·day−1 measured by accelerometer.Efficacy analysis (with per-protocol analysis set, n=233 classified as adherent to the assigned intervention) showed adjusted (95% CI) 12-month difference +957 (184–1731) steps·day−1 between Urban Training and usual care. Effectiveness analysis (with intention-to-treat analysis set, n=280 patients completing the study at 12 months including unwilling and self-reported non-adherent patients) showed no differences between groups. Leg muscle pain during walks was more frequently reported in Urban Training than usual care, without differences in any of the other adverse events.Urban Training, combining behavioural strategies with unsupervised outdoor walking, was efficacious in increasing physical activity after 12 months in COPD patients, with few safety concerns. However, it was ineffective in the full population including unwilling and self-reported non-adherent patients.

Determinants and outcomes of change in physical activity in COPD.

Determinants of change in physical activity and outcomes of physical activity promotion are unclear. In this secondary analysis of a randomised controlled trial of a physical activity intervention, we assess predictors of change in physical activity and the effects of increasing physical activity on chronic obstructive pulmonary disease (COPD) measures.Physical activity was promoted in 94 subjects with COPD using the Omron HJ-720ITC pedometer alone or the pedometer plus a website that provides goal setting, feedback, motivational and educational messages, and social support for 3 months. We assessed forced expiratory volume in 1 s (FEV1), 6-min walk test (6MWT) distance, depression, social support and markers of systemic inflammation (C-reactive protein (CRP) and interleukin (IL)-6). Data from both groups were combined and subjects categorised as responders (increased steps per day) or nonresponders (decreased steps per day). Linear regression models explored predictors of change in physical activity and assessed the effect of response on changes in COPD measures.The cohort of responders (n=62) and nonresponders (n=32) had mean FEV1 1.89±0.64 L (63±22% predicted). Baseline steps per day, diagnosis of depression, social support, oxygen use and season significantly predicted change in daily step count. Responders had increases in physical activity (2038 steps per day), FEV1 (308 mL) and 6MWT distance (43.6 m), and decreases in CRP (7.84 mg·L−1) and IL-6 (2.73 ng·mL−1) compared with nonresponders (p<0.0001–0.009).History of depression, social support, oxygen use and season predict change in physical activity, and should be routinely assessed in exercise counselling. Increases in physical activity are associated with improvements in lung function, exercise capacity and systemic inflammation.

Clinician-Facilitated Physical Activity Intervention Versus Pulmonary Rehabilitation for Improving Physical Activity in COPD: A Feasibility Study

Pulmonary rehabilitation (PR) may not suit all individuals with chronic obstructive pulmonary disease (COPD) and may not result in increased physical activity. Higher levels of physical activity are associated with reduced mortality and morbidity. The aim of this study was to assess the feasibility of conducting a trial to investigate the effectiveness of a clinician-facilitated physical activity intervention (PAI) versus PR in improving physical activity in patients with COPD referred to PR. In this randomised controlled mixed methods feasibility study, all patients referred to PR who were eligible and willing were assessed at baseline and then randomised to the PAI or to PR. The assessments were repeated post-intervention and at 3-month follow-up. The main outcome was step count measured by Actigraph. Semi-structured interviews were conducted post-intervention. The N = 50 patients; mean (SD) age, 64.1(8.6) years, 24M were recruited and randomised; N = 23 (PAI) and n = 26 (PR): one patient was excluded from the analysis as that person did not meet the GOLD diagnostic criteria. Key feasibility criteria were met; recruitment was 11%, dropouts in PAI were 26% (n = 6) and 50% (n = 13/26) PR. Participants in both groups experienced a range of health benefits from their respective programmes. The PAI appears to be effective in increasing step counts in people with COPD: mean change (standard deviation) [confidence interval] for the PAI group was 972.0(3230.3)[–1080.3 to 3024.4], n = 12 and 4.3(662.7)[-440.9 to 449.5], n = 11 for the PR group. The PAI met all domains of fidelity. This study provides key information to inform a future-randomised controlled trial in physical activity.

An “Exercise Vital Sign” Is a Valid Proxy Measure of Physical Activity in COPD in Routine Clinical Care

ABSTRACT Measurement of physical activity (PA) during routine care is currently not performed in most health systems. An “exercise vital sign” (EVS) is routinely assessed and entered into the electronic medical records at Kaiser Permanente. The purpose of this article is to examine the construct validity of the EVS for measuring PA in patients with chronic obstructive pulmonary disease (COPD). Patients with COPD who had a history of a COPD exacerbation requiring an admission, observational stay, or emergency department visit in the previous 12 months were included in the study. Baseline data of patients with COPD who were included in a pragmatic trial of a PA coaching intervention were used. Patients were classified as being inactive (0 min · wk−1 of moderate to vigorous PA), insufficiently active (1–149 min · wk−1), and active (150+ min · wk−1) using all available EVS data in the 12 months before identification for the study. The relationship between the EVS and standardized measures of COPD disease severity, functional performance, quality of life and symptoms were examined to establish construct validity. Because of the variable data collection scheme, data were available for 172 to 1834 patients. Patients with higher levels of PA, as categorized by the EVS, tended to have fewer comorbidities and less airway obstruction, used less supplemental oxygen, had higher 6-min walk test distance, and had more objectively measured PA, higher quality of life, and lower depressive symptoms compared with inactive and insufficiently active patients. In conclusion, the EVS provides a valid proxy measure of PA in patients with COPD and may be an efficient measure to assess PA during routine care compared with lengthy questionnaires or objectively measured PA.

SIRT1 and FOXO1 mRNA expression in PBMC correlates to physical activity in COPD patients.

BackgroundPhysical activity (PA) is considered as one of the most important prognostic predictors in chronic obstructive pulmonary disease (COPD) patients. Longevity gene, SIRT1, is reported to be involved in the pathogenesis of COPD by regulating the signaling pathways of oxidative stress, inflammation, and aging. We hypothesize that SIRT1 and related genes are also associated with the benefits of PA in COPD patients.MethodsEighteen COPD outpatients were enrolled in this study, and their PA level was assessed with an accelerometer. We assessed the SIRT1 and related genes mRNA expression levels in the peripheral blood mononuclear cells (PBMCs) of the subjects. We carried out respiratory function testing, blood gas analysis, the 6-minute walk test, and measurement of the cross-sectional area of the erector spinae muscles (ESMCSA) by chest computed tomography. We analyzed the association of PA with the results of each of the examinations.ResultsThe mean age was 72±9 years, and the mean forced expiratory volume in 1 second was 1.4±0.56 L (52%±19% predicted). Our findings revealed a correlation between the daily PA and ESMCSA. The SIRT1 and Forkhead box O (FOXO)1 mRNA expression levels in PBMCs were positively correlated with moderate-PA time (r=0.60, p=0.008 for SIRT1 and r=0.59, p=0.01 for FOXO1).

Socio-environmental correlates of physical activity in patients with chronic obstructive pulmonary disease (COPD)

BackgroundStudy of the causes of the reduced levels of physical activity in patients with COPD has been scarce and limited to biological factors.AimTo assess the relationship between novel socio-environmental factors,...

Physical activity patterns and clusters in 1001 patients with COPD.

We described physical activity measures and hourly patterns in patients with chronic obstructive pulmonary disease (COPD) after stratification for generic and COPD-specific characteristics and, based on multiple physical activity measures, we identified clusters of patients. In total, 1001 patients with COPD (65% men; age, 67 years; forced expiratory volume in the first second [FEV1], 49% predicted) were studied cross-sectionally. Demographics, anthropometrics, lung function and clinical data were assessed. Daily physical activity measures and hourly patterns were analysed based on data from a multisensor armband. Principal component analysis (PCA) and cluster analysis were applied to physical activity measures to identify clusters. Age, body mass index (BMI), dyspnoea grade and ADO index (including age, dyspnoea and airflow obstruction) were associated with physical activity measures and hourly patterns. Five clusters were identified based on three PCA components, which accounted for 60% of variance of the data. Importantly, couch potatoes (i.e. the most inactive cluster) were characterised by higher BMI, lower FEV1, worse dyspnoea and higher ADO index compared to other clusters (p < 0.05 for all). Daily physical activity measures and hourly patterns are heterogeneous in COPD. Clusters of patients were identified solely based on physical activity data. These findings may be useful to develop interventions aiming to promote physical activity in COPD.

Association between morning symptoms and physical activity in COPD: a systematic review.

Morning symptoms are common in chronic obstructive pulmonary disease (COPD). Many COPD patients consider the morning as the most troublesome part of the day, in which they experience more symptoms and physical activity limitations.To systematically report evidence of the association between morning symptoms and physical activity in COPD patients, a literature search was conducted using relevant MESH terms and text words in PubMed, Embase, Web of Science, COCHRANE, CINAHL and PsycINFO. Quality of the articles was assessed with validated checklists.Eight studies were included. Morning symptoms were present in 39.8-94.4%. In 37.0-90.6% of all COPD patients, there was an association between physical activity and morning symptoms. However, causality could not be proved. Morning symptoms were associated with a sedentary lifestyle (p<0.05). Treatment in line with the guidelines improved the degree of activity limitations due to morning symptoms (p<0.0001).Across all disease stages, COPD patients experience morning symptoms which are negatively associated with physical activity. Physicians should consider morning symptoms as a treatment goal. Pharmacotherapy may improve the degree of activity limitations due to morning symptoms. More objective research should focus on symptoms, activity limitations and physical inactivity of COPD patients, especially in the morning.

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

The broad range of interventions to increase physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) has not been systematically assessed. We aimed to perform a systematic review of the interventional studies that have assessed PA as an outcome in patients with COPD.A systematic search in five different databases (Medline, Embase, PsycINFO, CINAHL and Web of Science) was performed in March 2015. Two independent reviewers analysed the studies against the inclusion criteria (COPD defined by spirometry; prospective, randomised/nonrandomised studies, cohort and experimental studies with interventions using PA as an outcome), extracted the data and assessed the quality of evidence.60 studies were included. Seven intervention groups were identified. PA counselling increased PA levels in COPD, especially when combined with coaching. 13 studies showed positive effects of pulmonary rehabilitation (PR) on PA, while seven studies showed no changes. All three PR programmes >12 weeks in duration increased PA. Overall, the quality of evidence was graded as very low.Interventions focusing specifically on increasing PA, and longer PR programmes, may have greater impacts on PA in COPD. Well-designed clinical trials with objective assessment of PA in COPD patients are needed.