Gait differences between COPD and healthy controls: systematic review and meta-analysis.

BACKGROUND: Despite the importance of gait as a determinant of falls, disability and mortality in older people, understanding of gait impairment in COPD is limited. This study aimed to identify differences in gait characteristics during supervised walking tests between people with COPD and healthy controls. METHODS: We searched 11 electronic databases, supplemented by Google Scholar searches and manual collation of references, in November 2019 and updated the search in July 2021. Record screening and information extraction were performed independently by one reviewer and checked for accuracy by a second. Meta-analyses were performed in studies not considered at a high risk of bias. RESULTS: Searches yielded 21 085 unique records, of which 25 were included in the systematic review (including 1015 people with COPD and 2229 healthy controls). Gait speed was assessed in 17 studies (usual speed: 12; fast speed: three; both speeds: two), step length in nine, step duration in seven, cadence in six, and step width in five. Five studies were considered at a high risk of bias. Low-quality evidence indicated that people with COPD walk more slowly than healthy controls at their usual speed (mean difference (MD) -19 cm·s-1, 95% CI -28 to -11 cm·s-1) and at a fast speed (MD -30 cm·s-1, 95% CI -47 to -13 cm·s-1). Alterations in other gait characteristics were not statistically significant. CONCLUSION: Low-quality evidence shows that people with COPD walk more slowly than healthy controls, which could contribute to an increased falls risk. The evidence for alterations in spatial and temporal components of gait was inconclusive. Gait impairment appears to be an important but understudied area in COPD.

Physical activity coaching in patients with interstitial lung diseases: A randomized controlled trial.

OBJECTIVES: Physical activity is reduced in patients with interstitial lung disease (ILD) and physical inactivity is related to poor health outcomes. We investigated the effect of a telecoaching intervention to improve physical activity in patients with ILD. METHODS: Eighty patients with ILD were randomized into the intervention or control group. Patients in the intervention group received a 12-week telecoaching program including a step counter, a patient-tailored smartphone application, and coaching calls. Patients in the control group received usual care. Physical activity (primary outcome), physical fitness and quality of life were measured at baseline and 12 weeks later with an accelerometer, 6-min walking test and quadriceps muscle force and the King's Brief Interstitial Lung Disease questionnaire (K-BILD). RESULTS: Participation in telecoaching did not improve physical activity: between-group differences for step count: 386 ± 590 steps/day, p = .52; sedentary time: 4 ± 18 min/day, p = .81; movement intensity: 0.04 ± 0.05 m/s2, p = .45). Between-group differences for the 6-min walking test, quadriceps muscle force and K-BILD were 14 ± 10 m, p = .16; 2 ± 3% predicted, p = .61; 0.8 ± 1.7 points, p = .62 respectively. CONCLUSIONS: Twelve weeks of telecoaching did not improve physical activity, physical fitness or quality of life in patients with ILD. Future physical or behavioural interventions are needed for these patients to improve physical activity.

The Association between Objectively Measured Physical Activity and the Prevalence of Comorbidities in Lung Transplant Recipients.

INTRODUCTION: Lung transplant recipients are often physically inactive and are at risk of developing comorbidities. We investigated whether objectively measured physical activity was associated with the prevalence of comorbidities. METHODS: Physical activity (accelerometry) and the presence of cardiovascular disease, symptoms of depression and anxiety, diabetes, dyslipidaemia, hypertension, lower extremity artery disease, muscle weakness, obesity, and osteoporosis were assessed in 108 lung transplant recipients. Patients were divided into four groups based on daily step count. RESULTS: A cohort of 108 patients (60 ± 7 years, 51% male, 20 ± 14 months since transplantation) was included. Active patients (>7,500 steps/day) had significantly fewer comorbidities (4 comorbidities) compared to severely inactive patients (<2,500 steps/day, 6 comorbidities), and muscle weakness and high symptoms of depression were less prevalent. Severely inactive patients had significantly more cardiovascular comorbidities compared to all other groups. No other significant differences were observed. CONCLUSION: Physically active lung transplant recipients have fewer comorbidities, lower prevalence of muscle weakness, and fewer symptoms of depression compared to very inactive patients.

Development and feasibility of an exercise training program in primary care for patients with COPD experiencing an acute exacerbation.

BACKGROUND: Starting rehabilitation soon after an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is crucial to diminish the detrimental effects of this acute event on muscle function. However, uptake in outpatient pulmonary rehabilitation is low. OBJECTIVES: To design and test a feasible, acceptable and accessible exercise training program (ETP) in primary care for patients experiencing an AECOPD. DESIGN: (1) A literature review and qualitative study to develop an ETP and (2) A feasibility study of the ETP implemented in primary care. METHODS: (1) The development of the ETP proceeded in several phases with input from different stakeholders through focus group discussions. (2) Patients experiencing a moderate or severe AECOPD were included and followed the ETP for two weeks with a physiotherapist in primary care. Interviews with the participants took place and patients were given the choice to complete the eight-week program. RESULTS: (1) Six discussion sessions took place. The ETP contained a flexible set of progressively more difficult exercises applicable in a primary care practice. (2) Eight patients experiencing a moderate (n = 1) or severe (n = 7) AECOPD were included. Patients started the first physiotherapy session 5 (2-6) days after the start of their symptoms or hospital discharge. Seven patients wanted to complete the ETP. CONCLUSIONS: An ETP in primary care is feasible, acceptable and accessible for patients experiencing a moderate or severe AECOPD, and for physiotherapists. The effectiveness of this ETP on muscle function and physical activity is currently under investigation in a RCT. CONTRIBUTION OF THE PAPER.

The association of weather conditions with day-to-day variability in physical activity in patients with COPD.

Background: While patients with COPD often cite weather conditions as a reason for inactivity, little is known about the relationship between physical activity (PA) and weather conditions. The present study investigated the association of day-to-day weather changes on PA in patients with COPD and investigated patient characteristics related to being more or less influenced by weather conditions. Methods: In this longitudinal analysis, device-based day-by-day step counts were objectively measured in COPD patients for up to 12 months. Daily meteorological data (temperature, precipitation, wind speed, hours of sunlight and daylight) were linked to the daily step count and individual and multivariable relationships were investigated using mixed-model effects. Individual R2 was calculated for every subject to investigate the estimated influence of weather conditions on a patient level and its relationship with patient characteristics. Results: We included 50 patients with a mean±sd follow-up time of 282±93 days, totalling 14 117 patient-days. Daily temperature showed a positive linear pattern up until an inflexion point, after which a negative association with increasing temperature was observed (p<0.0001). Sunshine and daylight time had a positive association with PA (p<0.0001). Precipitation and wind speed were negatively associated with PA (p<0.0001). The median per-patient R2 for overall weather conditions was 0.08, ranging from 0.00 to 0.42. No strong associations between patient characteristics and per-patient R2 were observed. Conclusion: Weather conditions are partly associated with PA in patients with COPD, yet the overall explained variance of PA due to weather conditions is rather low and varied strongly between individuals.

Factors associated to physical activity in patients with COPD: An ecological approach.

BACKGROUND: Physical activity (PA) is low in patients with Chronic Obstructive Pulmonary Disease (COPD). Identifying modifiable and non-modifiable correlates of PA give understanding of the individual behavior and provide future directions for PA enhancing interventions. As PA is complex and multidimensional, it should be embedded within a thorough framework. OBJECTIVE: To identify correlates of PA in a comprehensive COPD population based on a broad ecological model, including physiological, psychological, socio-demographic and environmental dimensions. METHODS: PA was objectively measured using the Dynaport Movemonitor and a comprehensive data collection of physiological, psychological, socio-demographic and environmental factors were collected. Bivariable and multivariable regression analyses (including principle component analysis) were executed. RESULTS: For this cross-sectional analysis, we included 148 patients with COPD and valid PA data (mean (SD) age 68 (7) years, FEV1 57 (17) % predicted, 5613 (3596) steps per day). Significant bivariable associations were found for physiological (exercise capacity, muscle force, lung function, symptoms, comorbidities), psychological (e.g. fatigue, motivation, perceived difficulty with PA), socio-demographic (dog owning, use of activity tracker) and environmental (season, daylight, temperature) factors. Based on the multivariable regression model, exercise capacity, beliefs on motivation, importance and self-confidence regarding PA and weather conditions were independent correlates of mean steps per day (R2 = 0.35). Movement intensity during walking was only independently associated with exercise capacity and age (R2 = 0.41). CONCLUSION: Although a wide range of potential influence factors were evaluated, variance in PA was only partly explained, supporting that PA is a complex behavior which is difficult to predict.

Can COPD Exacerbations Be Picked Up Early via a Weekly Medication Question Through a Smartphone Application?

Background: Exacerbations affect the disease trajectory of patients with COPD and result in an acute drop of functional status and physical activity. Timely detection of exacerbations by non-medical healthcare professionals is needed to counteract this decline. The use of digital health applications in patient interaction allows embedded detection of exacerbations. However, it is unknown if this is an effective way to pick up exacerbations. Method: We investigated the detection of exacerbations in patients with COPD enrolled in a physical activity coaching program, by prompting a weekly question on changes in medication via the smartphone application. Data on response rate and occurrence of exacerbations were collected. Results: Response rate to the medication question, evaluated in 42 patients, was 72% (n = 497). A change in medication was reported through the smartphone application in 38 (7.6%) of the answered questions. The response rate was significantly lower at 6 months follow-up compared to the first month (p =0.03). When evaluating the occurrence of adverse events in a subset of patients who completed 6 months of follow-up (n = 27), 18 exacerbations were registered in eight patients, of which 10 of these exacerbations (56%) were picked up by the medication question in the coaching application. Conclusion: Electronic interaction through a weekly medication question, embedded in a smartphone application, is feasible to support the detection of the occurrence of COPD exacerbations and can be used complementary to regular forms of detecting exacerbations. Compliance and smartphone literacy should be optimized when further using this method to report on COPD exacerbations.