Endurance Time During Constant Work Rate Cycle Ergometry in COPD: Development of an Integrated Database From Interventional Studies

INTRODUCTION: The COPD Biomarkers Qualification Consortium (CBQC) was formed under COPD Foundation management, with the goal of qualifying biomarkers and clinical outcome assessments through established regulatory processes for chronic obstructive pulmonary disease (COPD). Within CBQC, a working group evaluated opportunities for qualification of an exercise endurance measure. In a recent publication (Chronic Obstr Pulm Dis. 2022; 9[2]:252-265), we described a conceptual framework establishing exercise endurance's direct relationship to an individual with COPD's experience of physical functioning in daily life, and that increase in exercise endurance is a patient-centered, meaningful treatment benefit. We further proposed endurance time during constant work rate cycle ergometery (CWRCE) as a useful efficacy endpoint in clinical therapeutic intervention trials. In this current publication, we describe the process of assembling an integrated database of endurance time responses to interventions in COPD.

METHODS: We sought participant-level data from published studies incorporating CWRCE as an outcome measure. A literature search screened 2993 publications and identified 553 studies for assessment. Two interventions had sufficient data across studies to warrant data extraction: bronchodilators and rehabilitative exercise training. Investigators were contacted and requested to provide participant-by-participant data from their published studies.

RESULTS: The final dataset included data from 8 bronchodilator studies (2166) participants and 15 exercise training studies (3488 participants). The database includes 71 variables per participant, comprising demographic, pulmonary function, and detailed physiologic response data. This paper provides a detailed description of the analysis population, while analysis supporting the validation/qualification process and addressing other scientific questions will be described in subsequent publications.