1. Abnormal Exertional Breathlessness on Cardiopulmonary Cycle Exercise Testing in Relation to Self-Reported and Physiologic Responses in Chronic Airflow Limitation
- Author
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Ekström, Magnus; https://orcid.org/0000-0002-7227-5113, Li, Pei Zhi, Lewthwaite, Hayley, Bourbeau, Jean; https://orcid.org/0000-0002-7649-038X, Tan, Wan C; https://orcid.org/0000-0001-9289-3595, Jensen, Dennis, CanCOLD Collaborative Research Group, Ekström, Magnus; https://orcid.org/0000-0002-7227-5113, Li, Pei Zhi, Lewthwaite, Hayley, Bourbeau, Jean; https://orcid.org/0000-0002-7649-038X, Tan, Wan C; https://orcid.org/0000-0001-9289-3595, Jensen, Dennis, and CanCOLD Collaborative Research Group
- Abstract
BACKGROUND Exertional breathlessness is a cardinal symptom of cardiorespiratory disease. RESEARCH QUESTION How does breathlessness abnormality, graded using normative reference equations during cardiopulmonary exercise testing (CPET), relate to self-reported and physiologic responses in people with chronic airflow limitation (CAL)? STUDY DESIGN AND METHODS An analysis was done of people aged ≥ 40 years with CAL undergoing CPET in the Canadian Cohort Obstructive Lung Disease study. Breathlessness intensity ratings (Borg CR10 scale [0-10 category-ratio scale for breathlessness intensity rating]) were evaluated in relation to power output, rate of oxygen uptake, and minute ventilation at peak exercise, using normative reference equations as follows: (1) probability of breathlessness normality (probability of having an equal or greater Borg CR10 rating among healthy people; lower probability reflecting more severe breathlessness) and (2) presence of abnormal breathlessness (rating above the upper limit of normal). Associations with relevant participant-reported and physiologic outcomes were evaluated. RESULTS We included 330 participants (44% women): mean ± SD age, 64 ± 10 years (range, 40-89 years); FEV$_{1}$/FVC, 57.3% ± 8.2%; FEV$_{1}$, 75.6% ± 17.9% predicted. Abnormally low exercise capacity (peak rate of oxygen uptake < lower limit of normal) was present in 26%. Relative to peak power output, rate of oxygen uptake, and minute ventilation, abnormally high breathlessness was present in 26%, 25%, and 18% of participants. For all equations, abnormally high exertional breathlessness was associated with worse lung function, exercise capacity, self-reported symptom burden, physical activity, and health-related quality of life; and greater physiologic abnormalities during CPET. INTERPRETATION Abnormal breathlessness graded using CPET normative reference equations was associated with worse clinical, physiological, and functional outcomes in people with CAL, supporting cons
- Published
- 2024