Elena Gimeno-Santos

An official European Respiratory Society statement on physical activity in COPD

This European Respiratory Society (ERS) statement provides a comprehensive overview on physical activity in patients with chronic obstructive pulmonary disease (COPD). A multidisciplinary Task Force of experts representing the ERS Scientific Group 01.02 “Rehabilitation and Chronic Care” determined the overall scope of this statement through consensus. Focused literature reviews were conducted in key topic areas and the final content of this Statement was agreed upon by all members. The current knowledge regarding physical activity in COPD is presented, including the definition of physical activity, the consequences of physical inactivity on lung function decline and COPD incidence, physical activity assessment, prevalence of physical inactivity in COPD, clinical correlates of physical activity, effects of physical inactivity on hospitalisations and mortality, and treatment strategies to improve physical activity in patients with COPD. This Task Force identified multiple major areas of research that need to be addressed further in the coming years. These include, but are not limited to, the disease-modifying potential of increased physical activity, and to further understand how improvements in exercise capacity, dyspnoea and self-efficacy following interventions may translate into increased physical activity. The Task Force recommends that this ERS statement should be reviewed periodically (e.g. every 5–8 years). An official ERS statement providing a comprehensive overview on physical activity in patients with COPD http://ow.ly/C6v78

Validity of activity monitors in health and chronic disease: a systematic review

The assessment of physical activity in healthy populations and in those with chronic diseases is challenging. The aim of this systematic review was to identify whether available activity monitors (AM) have been appropriately validated for use in assessing physical activity in these groups. Following a systematic literature search we found 134 papers meeting the inclusion criteria; 40 conducted in a field setting (validation against doubly labelled water), 86 in a laboratory setting (validation against a metabolic cart, metabolic chamber) and 8 in a field and laboratory setting. Correlation coefficients between AM outcomes and energy expenditure (EE) by the criterion method (doubly labelled water and metabolic cart/chamber) and percentage mean differences between EE estimation from the monitor and EE measurement by the criterion method were extracted. Random-effects meta-analyses were performed to pool the results across studies where possible. Types of devices were compared using meta-regression analyses. Most validation studies had been performed in healthy adults (n = 118), with few carried out in patients with chronic diseases (n = 16). For total EE, correlation coefficients were statistically significantly lower in uniaxial compared to multisensor devices. For active EE, correlations were slightly but not significantly lower in uniaxial compared to triaxial and multisensor devices. Uniaxial devices tended to underestimate TEE (−12.07 (95%CI; -18.28 to −5.85) %) compared to triaxial (−6.85 (95%CI; -18.20 to 4.49) %, p = 0.37) and were statistically significantly less accurate than multisensor devices (−3.64 (95%CI; -8.97 to 1.70) %, p<0.001). TEE was underestimated during slow walking speeds in 69% of the lab validation studies compared to 37%, 30% and 37% of the studies during intermediate, fast walking speed and running, respectively. The high level of heterogeneity in the validation studies is only partly explained by the type of activity monitor and the activity monitor outcome. Triaxial and multisensor devices tend to be more valid monitors. Since activity monitors are less accurate at slow walking speeds and information about validated activity monitors in chronic disease populations is lacking, proper validation studies in these populations are needed prior to their inclusion in clinical trials.

Determinants and outcomes of physical activity in patients with COPD: a systematic review

Background The relationship between physical activity, disease severity, health status and prognosis in patients with COPD has not been systematically assessed. Our aim was to identify and summarise studies assessing associations between physical activity and its determinants and/or outcomes in patients with COPD and to develop a conceptual model for physical activity in COPD. Methods We conducted a systematic search of four databases (Medline, Embase, CINAHL and Psychinfo) prior to November 2012. Teams of two reviewers independently selected articles, extracted data and used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to assess quality of evidence. Results 86 studies were included: 59 were focused on determinants, 23 on outcomes and 4 on both. Hyperinflation, exercise capacity, dyspnoea, previous exacerbations, gas exchange, systemic inflammation, quality of life and self-efficacy were consistently related to physical activity, but often based on cross-sectional studies and low-quality evidence. Results from studies of pharmacological and non-pharmacological treatments were inconsistent and the quality of evidence was low to very low. As outcomes, COPD exacerbations and mortality were consistently associated with low levels of physical activity based on moderate quality evidence. Physical activity was associated with other outcomes such as dyspnoea, health-related quality of life, exercise capacity and FEV1 but based on cross-sectional studies and low to very low quality evidence. Conclusions Physical activity level in COPD is consistently associated with mortality and exacerbations, but there is poor evidence about determinants of physical activity, including the impact of treatment.

Sildenafil to improve respiratory rehabilitation outcomes in COPD: a controlled trial

Pulmonary hypertension is a serious complication of chronic obstructive pulmonary disease (COPD) that currently has no established pharmacological treatment. This study aimed to assess whether concomitant treatment with sildenafil would enhance the results of pulmonary rehabilitation in patients with COPD and increased pulmonary arterial pressure (PAP). In this double-blind, randomised controlled trial patients received 20 mg sildenafil or placebo three times daily and underwent pulmonary rehabilitation for 3 months. The primary end-point was the gain in the cycle endurance time at a constant work-rate. Secondary end-points included performance in the incremental exercise test, 6-min walk distance and quality of life. 63 patients with severe COPD and moderately increased PAP were randomised. Cycle endurance time increased by 149 s (95% CI 26–518 s) in the sildenafil group and by 169 s (95% CI 0–768 s) in the placebo group (median change difference -7 s, 95% CI -540–244 s; p=0.77). Gains in the incremental exercise test, 6-min walk distance and quality of life at the end of the study did not differ between groups. Measurements of arterial oxygenation and adverse events were similar in both groups. In patients with severe COPD and moderately increased PAP, concomitant treatment with sildenafil does not improve the results of pulmonary rehabilitation in exercise tolerance. Sildenafil did not improve respiratory rehabilitation outcomes in patients with severe COPD and moderately increased PAP http://ow.ly/lh7cb

Physical activity in COPD patients: patterns and bouts

The present study aims to describe the pattern of physical activity and the frequency, duration and intensity of physical activity bouts in patients with chronic obstructive pulmonary disease (COPD), to assess how these patterns differ according to COPD severity, and to explore whether these patients meet the general guidelines for physical activity for older adults. 177 patients (94% male, mean±sd age 71±8 years and forced expiratory volume in 1 s 52±16% predicted) wore the SenseWear Pro2 Armband accelerometer for eight consecutive days. Physical activity bouts were defined as periods of ≥10 min above 1.5 metabolic equivalent tasks and classified according to their median intensity. Patients engaged in activity a median of 153 min·day−1 and 57% of that time was spent in bouts. Median frequencies of bouts per day were four and three for all and moderate-to-vigorous intensities, respectively. With increasing COPD severity, time in physical activity, proportion of time in bouts and frequency of bouts decreased. 61% of patients fulfilled the recommended physical activity guidelines. In conclusion, COPD patients of all spirometric severity stages engage in physical activity bouts of moderate-to-vigorous intensities. Patients with severe and very severe COPD perform their daily activities in fewer and shorter bouts than those in mild and moderate stages. Patients with severe COPD perform their daily activities in fewer, shorter bouts than those in mild and moderate stages http://ow.ly/nug7k

The PROactive instruments to measure physical activity in patients with chronic obstructive pulmonary disease

No current patient-centred instrument captures all dimensions of physical activity in chronic obstructive pulmonary disease (COPD). Our objective was item reduction and initial validation of two instruments to measure physical activity in COPD. Physical activity was assessed in a 6-week, randomised, two-way cross-over, multicentre study using PROactive draft questionnaires (daily and clinical visit versions) and two activity monitors. Item reduction followed an iterative process including classical and Rasch model analyses, and input from patients and clinical experts. 236 COPD patients from five European centres were included. Results indicated the concept of physical activity in COPD had two domains, labelled “amount” and “difficulty”. After item reduction, the daily PROactive instrument comprised nine items and the clinical visit contained 14. Both demonstrated good model fit (person separation index >0.7). Confirmatory factor analysis supported the bidimensional structure. Both instruments had good internal consistency (Cronbachs α>0.8), test–retest reliability (intraclass correlation coefficient ≥0.9) and exhibited moderate-to-high correlations (r>0.6) with related constructs and very low correlations (r<0.3) with unrelated constructs, providing evidence for construct validity. Daily and clinical visit “PROactive physical activity in COPD” instruments are hybrid tools combining a short patient-reported outcome questionnaire and two activity monitor variables which provide simple, valid and reliable measures of physical activity in COPD patients. Both PROactive hybrid tools are simple, valid, and reliable measures of physical activity in COPD patients http://ow.ly/LJqP8

Physical activity is increased by a 12-week semiautomated telecoaching programme in patients with COPD: a multicentre randomised controlled trial

Rationale Reduced physical activity (PA) in patients with COPD is associated with a poor prognosis. Increasing PA is a key therapeutic target, but thus far few strategies have been found effective in this patient group. Objectives To investigate the effectiveness of a 12-week semiautomated telecoaching intervention on PA in patients with COPD in a multicentre European randomised controlled trial. Methods 343 patients from six centres, encompassing a wide spectrum of disease severity, were randomly allocated to either a usual care group (UCG) or a telecoaching intervention group (IG) between June and December 2014. This 12-week intervention included an exercise booklet and a step counter providing feedback both directly and via a dedicated smartphone application. The latter provided an individualised daily activity goal (steps) revised weekly and text messages as well as allowing occasional telephone contacts with investigators. PA was measured using accelerometry during 1 week preceding randomisation and during week 12. Secondary outcomes included exercise capacity and health status. Analyses were based on modified intention to treat. Main results Both groups were comparable at baseline in terms of factors influencing PA. At 12 weeks, the intervention yielded a between-group difference of mean, 95% CI (lower limit – upper limit; ll-ul) +1469, 95% CI (971 to 1965) steps/day and +10.4, 95% CI (6.1 to 14.7) min/day moderate PA; favouring the IG (all p≤0.001). The change in 6-min walk distance was significantly different (13.4, 95% CI (3.40 to 23.5) m, p<0.01), favouring the IG. In IG patients, an improvement could be observed in the functional state domain of the clinical COPD questionnaire (p=0.03) compared with UCG. Other health status outcomes did not differ. Conclusions The amount and intensity of PA can be significantly increased in patients with COPD using a 12-week semiautomated telecoaching intervention including a step counter and an application installed on a smartphone. Trial registration number: NCT02158065.

Validity of instruments to measure physical activity may be questionable due to a lack of conceptual frameworks: a systematic review

BackgroundGuidance documents for the development and validation of patient-reported outcomes (PROs) advise the use of conceptual frameworks, which outline the structure of the concept that a PRO aims to measure. It is unknown whether currently available PROs are based on conceptual frameworks. This study, which was limited to a specific case, had the following aims: (i) to identify conceptual frameworks of physical activity in chronic respiratory patients or similar populations (chronic heart disease patients or the elderly) and (ii) to assess whether the development and validation of PROs to measure physical activity in these populations were based on a conceptual framework of physical activity.MethodsTwo systematic reviews were conducted through searches of the Medline, Embase, PsycINFO, and Cinahl databases prior to January 2010.ResultsIn the first review, only 2 out of 581 references pertaining to physical activity in the defined populations provided a conceptual framework of physical activity in COPD patients. In the second review, out of 103 studies developing PROs to measure physical activity or related constructs, none were based on a conceptual framework of physical activity.ConclusionsThese findings raise concerns about how the large body of evidence from studies that use physical activity PRO instruments should be evaluated by health care providers, guideline developers, and regulatory agencies.

Benefits of physical activity on COPD hospitalisation depend on intensity

The present study aims to disentangle the independent effects of the quantity and the intensity of physical activity on the risk reduction of chronic obstructive pulmonary disease (COPD) hospitalisations. 177 patients from the Phenotype Characterization and Course of COPD (PAC-COPD) cohort (mean±sd age 71±8 years, forced expiratory volume in 1 s 52±16% predicted) wore the SenseWear Pro 2 Armband accelerometer (BodyMedia, Pittsburgh, PA, USA) for eight consecutive days, providing data on quantity (steps per day, physically active days and daily active time) and intensity (average metabolic equivalent tasks) of physical activity. Information on COPD hospitalisations during follow-up (2.5±0.8 years) was obtained from validated centralised datasets. During follow-up 67 (38%) patients were hospitalised. There was an interaction between quantity and intensity of physical activity in their effects on COPD hospitalisation risk. After adjusting for potential confounders in the Cox regression model, the risk of COPD hospitalisation was reduced by 20% (hazard ratio (HR) 0.79, 95% CI 0.67–0.93; p=0.005) for every additional 1000 daily steps at low average intensity. A greater quantity of daily steps at high average intensity did not influence the risk of COPD hospitalisations (HR 1.01, p=0.919). Similar results were found for the other measures of quantity of physical activity. Greater quantity of low-intensity physical activity reduces the risk of COPD hospitalisation, but high-intensity physical activity does not produce any risk reduction. Greater quantity of low-intensity physical activity reduces the risk of COPD hospitalisation http://ow.ly/Oe2RE

Validación del cuestionario de actividad física de Yale en pacientes con enfermedad pulmonar obstructiva crónica

BACKGROUND Patients with chronic obstructive pulmonary disease (COPD) perform limited physical activity. Surprisingly, there is a lack of research in COPD about the validity of physical activity questionnaires. Our aim was to validate the Yale Physical Activity Survey in COPD patients in order to quantify and classify their levels of physical activity. METHODS 172 COPD patients from 8 university hospitals in Spain wore an accelerometer (SenseWear(®)Pro(2)Armband) for 8 days and answered the questionnaire 15 days later. Statistical analyses used to compare both tools measures included: (i) Spearmans correlation coefficient, (ii) intraclass correlation coefficient (ICC) and Bland-Altman plots, (iii) distribution of accelerometer measurements according to tertiles of the questionnaire, and (iv) receiver operating characteristic (ROC) curves to detect sedentary patients. RESULTS 94% of participants were men, 28% were active smokers and 7% were currently working. Mean (standard deviation) age was 70 (8) years, mean post-bronchodilator FEV(1) was 52 (15)% predicted, and median (p25-p75) steps taken was 5,702 (3,273-9,253) steps per day(-1). Spearman correlations were low to moderate (from 0.29 to 0.52, all P<.001). ICCs showed weak agreement (from 0.34 to 0.40, all P<.001). A wide variability in agreement was observed in the Bland-Altman plots. Significant differences in accelerometer measurements were found according to questionnaire tertiles (all P<.001). The area under the ROC for identifying sedentarism was 0.71 (95% CI: 0.63-0.79). CONCLUSIONS The Yale Physical Activity Survey may be a valid tool to classify, but not to quantify, physical activity performed by COPD patients. The summary index of this questionnaire, based on seven short questions, shows the best validity properties. This suggests that it should be considered a screening tool to identify patients at risk for sedentarism.