Factors most strongly associated with breathlessness in a population aged 50-64 years

Max Olsson; Anders J Björkelund; Jacob Sandberg; Anders Blomberg; Mats Börjesson; David Currow; Andrei Malinovschi; Magnus Sköld; Per Wollmer; Kjell Torén; Carl Johan Östgren; Gunnar Engström; Magnus Ekström

doi:10.1183/23120541.00582-2023

Factors most strongly associated with breathlessness in a population aged 50-64 years

ERJ Open Res. 2024 Mar 25;10(2):00582-2023. doi: 10.1183/23120541.00582-2023. eCollection 2024 Mar.

Authors

Max Olsson¹, Anders J Björkelund², Jacob Sandberg¹, Anders Blomberg³, Mats Börjesson^{4

5}, David Currow⁶, Andrei Malinovschi⁷, Magnus Sköld^{8

9}, Per Wollmer¹⁰, Kjell Torén¹¹, Carl Johan Östgren^{12

13}, Gunnar Engström¹⁴, Magnus Ekström¹

Affiliations

¹ Lund University, Faculty of Medicine, Department of Clinical Sciences Lund, Respiratory Medicine, Allergology and Palliative Medicine, Lund, Sweden.
² Lund University, Faculty of Science, Centre for Environmental and Climate Science, Lund, Sweden.
³ Umeå University, Department of Public Health and Clinical Medicine, Umeå, Sweden.
⁴ Dept of Molecular and Cardiovascular Medicine, Center for Health and Performance, Sahlgrenska Academy, Gothenburg, Sweden.
⁵ Dept MGAÖ, Sahlgrenska University Hospital, Gothenburg, Sweden.
⁶ Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, Australia.
⁷ Dept of Medical Sciences, Clinical Physiology, Uppsala University, Uppsala, Sweden.
⁸ Karolinska Institutet, Department of Medicine Solna, Stockholm, Sweden.
⁹ Department of Respiratory Medicine and Allergy, Karolinska University Hospital, Stockholm, Sweden.
¹⁰ Department of Translational Medicine, Lund University, Malmö, Sweden.
¹¹ Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
¹² Centre of Medical Image Science and Visualization, Linköping University, Linköping, Sweden.
¹³ Department of Health, Medicine and Caring Sciences, Linköping University, Linkoping, Sweden.
¹⁴ Lund University, Faculty of Medicine, Department of Clinical Sciences Malmö, Cardiovascular Epidemiology, Malmö, Sweden.

Abstract

Background: Breathlessness is a troublesome and prevalent symptom in the population, but knowledge of related factors is scarce. The aim of this study was to identify the factors most strongly associated with breathlessness in the general population and to describe the shapes of the associations between the main factors and breathlessness.

Methods: A cross-sectional analysis was carried out of the multicentre population-based Swedish CArdioPulmonary bioImage Study (SCAPIS) of adults aged 50 to 64 years. Breathlessness was defined as a modified Medical Research Council breathlessness rating ≥2. The machine learning algorithm extreme gradient boosting (XGBoost) was used to classify participants as either breathless or nonbreathless using 449 factors, including physiological measurements, blood samples, computed tomography cardiac and lung measurements, lifestyle, health conditions and socioeconomics. The strength of the associations between the factors and breathlessness were measured by SHapley Additive exPlanations (SHAP), with higher scores reflecting stronger associations.

Results: A total of 28 730 participants (52% women) were included in the study. The strongest associated factors for breathlessness were (in order of magnitude): body mass index ( SHAP score 0.39), forced expiratory volume in 1 s (0.32), physical activity measured by accelerometery (0.27), sleep apnoea (0.22), diffusing lung capacity for carbon monoxide (0.21), self-reported physical activity (0.17), chest pain when hurrying (0.17), high-sensitivity C-reactive protein (0.17), recent weight change (0.14) and cough (0.13).

Conclusion: This large population-based study of men and women aged 50-64 years identified the main factors related to breathlessness that may be prevented or amenable to public health interventions.