Designing and validating an experimental protocol to induce airway narrowing in older adults with and without asthma

Shaghayegh Chavoshian; Xiaoshu Cao; Anirudh Thommandram; Matthew B Stanbrook; Susan M Tarlo; Yan Fossat; Azadeh Yadollahi

doi:10.1186/s12938-023-01197-6

Designing and validating an experimental protocol to induce airway narrowing in older adults with and without asthma

Biomed Eng Online. 2024 Mar 6;23(1):28. doi: 10.1186/s12938-023-01197-6.

Authors

Shaghayegh Chavoshian^{1

2}, Xiaoshu Cao^{1

2}, Anirudh Thommandram³, Matthew B Stanbrook^{4

5}, Susan M Tarlo^{4

5

6}, Yan Fossat³, Azadeh Yadollahi^{7

8}

Affiliations

¹ KITE Research Institute, Toronto Rehabilitation Institute, University Health Network, 550 University Ave, Toronto, M5G 2A2, ON, Canada.
² Institute of Biomedical Engineering, University of Toronto, 164 College St., Toronto, M5S 3G9, ON, Canada.
³ Labs Department, Klick Health, Klick Inc, 175 Bloor St. East, Toronto, M4W 3R8, ON, Canada.
⁴ Department of Medicine, University of Toronto, 164 College St., Toronto, M5S 3G9, ON, Canada.
⁵ Department of Medicine, University Health Network Toronto Western Hospital, 399 Bathurst St., Toronto, M5T 2S8, ON, Canada.
⁶ Dalla Lana School of Public Health, University of Toronto, 155 College St., Toronto, M5T 1P8, ON, Canada.
⁷ KITE Research Institute, Toronto Rehabilitation Institute, University Health Network, 550 University Ave, Toronto, M5G 2A2, ON, Canada. azadeh.yadollahi@uhn.ca.
⁸ Institute of Biomedical Engineering, University of Toronto, 164 College St., Toronto, M5S 3G9, ON, Canada. azadeh.yadollahi@uhn.ca.

Abstract

Background: Persons with asthma may experience excessive airway narrowing due to exercise or exposure to cold air, worsening their daily functionality. Exercise has several benefits for asthma control, but it may induce airway narrowing in some persons with asthma. When combined with cold temperatures, it introduces another layer of challenges. Therefore, managing this interaction is crucial to increase the quality of life in individuals with asthma. The purpose of this study was to develop a reliable experimental protocol to assess the effects of exercise and cold air on airway narrowing in adults with asthma in a controlled and safe environment.

Methods: This study was a randomized cross-over study in adults with and without asthma. Participants underwent a protocol involving a 10-min seated rest, followed by a 10-min cycling on a stationary bike in different temperatures of 0, 10, or 20 $^{\circ}$ C. The sequence of room temperatures was randomized, and there was a 30-min interval for recovery between each temperature transition. In each temperature, to measure lung function and respiratory symptoms, oscillometry and a questionnaire were used at 0 min (baseline), after 10 min of sitting and before starting biking (pre-exercise), and after 10 min of biking (post-exercise). At each room temperature, the changes in airway mechanics and asthma symptoms among baseline, pre-exercise, and post-exercise were compared with one-way repeated measures ANOVA or Friedman Rank Test. Within each arm, cardiac and thoraco-abdominal motion respiration signals were also measured continuously using electrodes and calibrated respiratory inductance plethysmographs, respectively.

Results: A total of 23 persons with asthma (11 females, age: 56.3 ± 10.9 years, BMI: 27.4 ± 5.7 kg/m²) and 6 healthy subjects (3 females, age: 61.8 ± 9.1 years, BMI: 28.5 ± 3.1 kg/m²) were enrolled in the study. Cold temperature of 0 $^{\circ}$ C induced airway narrowing in those with and without asthma after 10 and 20 min, respectively. Exercise intervention had significant changes in airway narrowing in participants with asthma in the range of 10-20 $^{\circ}$ C. Our results showed that in asthma, changes in subjective respiratory symptoms were due to both cold temperatures of 0 and 10 $^{\circ}$ C and exercise in the 0-20 $^{\circ}$ C range. Respiratory symptoms were not noticed among the healthy participants.

Conclusion: In conclusion, our findings suggest that exposure to cold temperatures of 0 $^{\circ}$ C could serve as a reliable method in the experimental protocol for inducing airway narrowing in asthma. The impact of exercise on airway narrowing was more variable among participants. Understanding these triggers in the experimental protocol is essential for the successful management of asthma in future studies.

Keywords: Airway narrowing; Asthma; Cold temperature; Exercise; Experimental protocol.

Publication types

Clinical Trial Protocol

MeSH terms

Aged
Asthma*
Cold Temperature
Female
Humans
Middle Aged
Quality of Life*
Randomized Controlled Trials as Topic
Respiration
Temperature