Physical activity end-points in trials of chronic respiratory diseases: summary of evidence

Abstract

BackgroundPhysical activity (PA) contributes to improving respiratory symptoms. However, validated endpoints are few and there is limited consensus about what is a clinically meaningful improvement for patients. This review summarises the evidence to date on the range of PA endpoints used in chronic obstructive pulmonary disease (COPD), asthma and idiopathic pulmonary fibrosis (IPF) whilst evaluating their appropriateness as endpoints in trials and their relation to patients’ everyday life.MethodsTrials reporting PA endpoints were collected using Citeline's database Trialtrove; this was supplemented by searches in PubMed.ResultsThe daily-patient-reported outcome (PRO)active and clinical visit-PROactive physical activity (D-PPAC & C-PPAC) composite endpoints appeared superior at capturing the full experience of PA in patients with COPD and were responsive to bronchodilator intervention. Time spent in moderate-to-vigorous PA is a recently validated endpoint for IPF that correlates with exercise capacity and quality of life. Step count (SC) appears the best available PA measure for asthma which consistently declines with worse disease status. However, evidence suggests a time lag before significant improvement in SC is seen which may reflect the impact of human behaviour on PA.ConclusionsPA represents a challenging domain to accurately measure. This is the first review evaluating PA measures used specifically within the respiratory field. Whilst PA can be effectively captured using PROactive in patients with COPD, this review highlights the unmet need for novel patient-focused endpoints in asthma and IPF which would offer opportunities to develop efficacious medicines with impact on patients’ therapeutic care and quality of life.

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

“…Second, our analysis emphasised differences in post-intervention step-count between control and intervention groups, yet the many features affecting PA may not be captured in a single measurement. For that reason, future PA promotion-based studies should therefore aim to adopt a more holistic approach to assessment, with consideration for other relevant aspects or refined markers of PA, such as sports participation/structured exercise, time spent in sedentary living, moderate-to-vigorous activity and/or activity-related energy expenditure [ 80 ]. Third, some studies failed to report whether PA promotion interventions were evaluated in isolation or embedded within a pulmonary rehabilitation programme, which limited our ability to provide a direct comparison.…”

Use of Ecological Momentary Assessment to Measure Dyspnea in COPD

“…A validated patient-reported outcome tool such as the (PRO)active should be considered, as it captures the experience of physical activity with a strong correlation to dyspnea in patients with COPD. 51 …”

“…A validated patient-reported outcome tool such as the (PRO)active should be considered, as it captures the experience of physical activity with a strong correlation to dyspnea in patients with COPD. 51 Importantly, self-reported app data can be used to predict COPD exacerbations with moderate discriminative ability. An example of this is the myCOPD mobile app, a digital momentary assessment symptom diary for patients with COPD that tracks characteristics of long-term COPD status using the COPD Assessment Test (CAT).…”

Physiological changes related to 10 weeks of singing for lung health in patients with COPD

“…Neither did we include assessment of biomarkers, high-resolution chest CT, body plethysmography or ultrasound-measurement of diaphragmatic thickness or mobility to assess emphysema, hyperinflation, airway resistance, small airways involvement, or diaphragmatic strength. Neither of these are, however, standard in assessment of outcome of PR for COPD yet; however, it would be interesting and relevant to include such parameters in future research on SLH besides testing of physical activity (although challenging to measure), 51 EKG, and exercise stress test, for example chair stand test, in future studies.…”