TY - JOUR T1 - Reference equations for breathlessness during incremental cycle exercise testing JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00566-2022 SP - 00566-2022 AU - Viktor Elmberg AU - Linus Schiöler AU - Thomas Lindow AU - Kristofer Hedman AU - Andrei Malinovschi AU - Hayley Lewthwaite AU - Dennis Jensen AU - Lars Brudin AU - Magnus Ekström Y1 - 2023/01/01 UR - http://openres.ersjournals.com/content/early/2023/01/05/23120541.00566-2022.abstract N2 - Background Exertional breathlessness is commonly assessed using incremental exercise testing (IET), but reference equations for breathlessness responses are lacking. We aimed to develop reference equations for breathlessness intensity during IET.Methods Retrospective, consecutive cohort study of adults undergoing IET in Sweden. Exclusion criteria included cardiac or respiratory disease, death or any of the aforementioned diagnoses within 1 year of the IET, morbid obesity, abnormally low exercise capacity, submaximal exertion, or an abnormal exercise test. Probabilities for breathlessness intensity ratings (Borg CR10) during IET in relation to power output (%predWmax), age, sex, height, and body mass were analysed using marginal ordinal logistic regression. Reference equations for males and females were derived to predict the upper limit of normal (ULN), and the probability of different Borg CR10 intensity ratings.Results 2581 participants (43% female) aged 18–90 years were included. Mean breathlessness intensity was similar between sexes at peak exertion (6.7±1.5 versus 6.4±1.5 Borg CR10 units) and throughout exercise in relation to %predWmax. Final reference equations included age, height and %predWmax for males, whereas height was not included for females. The models showed a close fit to observed breathlessness intensity ratings across %predWmax values. Models using absolute W did not show superior fit. Scripts are provided for calculating the probability for different breathlessness intensity ratings, and the ULN by %predWmax throughout IET.Conclusion We present the first reference equations for interpreting breathlessness intensity during incremental cycle exercise testing in males and females aged 18–90 years.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: No conflicts of interest exist for the authors. ER -