Dr. Brandie Laurel Walker, MD, PhD, FRCPC, Clinical Lead
Dr. Walker is a University of Calgary trained Respirologist with a focus on airways diseases. She runs specialty clinics in both severe asthma as well as a multidisciplinary severe COPD clinic at Foothills Medical Centre. Dr. Walker has been Medical Director of the Calgary COPD and Asthma Program since 2014. She is the Respirology Site Lead for the Foothills Medical Centre as well as the site lead for the Respirology training program. She is program director for the Severe Asthma Fellowship Program at the University of Calgary. She is a member of the Airways Research Group at the University of Calgary and participates in clinical and pharmaceutical asthma and COPD research studies.

Dr. Richard Leigh, MBChB, MSc, PhD, FCP (SA), FRCPC, Asthma Research Lead
Richard Leigh is a physician-scientist and the Senior Associate Dean – Faculty Affairs in the Cumming School of Medicine at the University of Calgary.

He obtained his medical degree from the University of Cape Town, and subsequently undertook specialist and sub-specialist training in Internal Medicine and Pulmonology at the University of Cape Town, South Africa. This was followed by further research training in the areas of airway inflammation, asthma and COPD at McMaster University in Canada, where obtained a Masters degree in Health Research Methodology and a PhD in Medical Sciences.

Dr. Leigh’s areas of interest include understanding the basic mechanisms underlying airway remodeling in asthma, the assessment of airway inflammation and early phase clinical trials in asthma and COPD. His program of research studying the role of rhinovirus infections in the pathogenesis of airway remodeling in asthma is funded through a CIHR Project Grant.

His clinical practice focuses on severe asthma and other airways diseases, and he previously served as the Division Chief of Respiratory Medicine and as the Chair of the Department of Medicine before taking up his current appointment in January 2020.

Dr. Stephen K. Field, MD, CM, FRCPC, DABIM, CSPQ, FCCP
Dr. Field is a respirologist at Foothills Medical Centre and clinical professor at the University of Calgary. He has a large respiratory consultative practice and works in the tuberculosis and nontuberculous mycobacterial clinics. He cofounded the Calgary COPD and asthma program and founded the Calgary chronic cough clinic. Dr Field has participated in numerous clinical investigations and published over 100 articles in peer-reviewed journals as well as many abstracts, book chapters, and communications.

Dr. J. Michael Ramsahai, MD, FRCPC
Dr. Ramsahai completed his training in Adult Respirology at the University of Calgary before pursuing advanced training in Severe Asthma at the John Hunter Hospital and University of Newcastle in Australia. Since then, his practice based at the Rockyview General Hospital sees general respirology and severe asthma patients. He is currently the physician lead for the Adolescent Transition Asthma Clinic based at the same site, and the Medical Director for the Calgary Zone Pulmonary Function Labs. He is the primary physician preceptor for the severe asthma fellowship program at the Rockyview General Hospital and is an active member of the Airways Research Group at the University of Calgary.


  • Erika Penz, Michael Stickland and Brandie Walker. Chronic Obstructive Pulmonary Disease (Year in Review). Canadian Journal of Respiratory, Critical Care and Sleep Medicine 2021, Vol 5, No 2, 84-88.

  • Leung C, Bourbeau J, Sin DD, Aaron SD, FitzGerald JM, Maltais F, Marciniuk DD, O’Donnell D, Hernandez P, Chapman KR, Walker B, Road JD, Zheng L, Zou C, Hogg JC, Tan WE The Prevalence of Chronic Obstructive Pulmonary Disease (COPD) and the Heterogeneity of Risk Factors in the Canadian Population: Results from the Canadian Obstructive Lung Disease (COLD) Study.; Int J Chron Obstruct Pulmon Dis. 2021 Feb 12;16:305-320.

  • Selvanathan J, Aaron SD, Sykes JM, Vandemheen KL, FitzGerald JM, Ainslie M, Lemière C, Field SK, McIvor RA, Hernandez P, Mayers I, Mulpuru S, Alvarez GA, Pakhale S, Mallick R, Boulet LP, Gupta S, for the Canadian Respiratory Research Network. Diagnostic accuracy and reliability of spirometry with bronchodilator testing and serial methacholine challenge testing for diagnosis of adult asthma. Chest 2020 Aug; 158(2):479-DOI:

  • Preteroti M, Whitmore GA, Vandemheen KL, FitzGerald JM, Lemière C, Boulet LP, Penz E, Field SK, Gupta S, McIvor RA, Mayers I, Hernandez P, Lougheed D, Ainslie M, Licskai C, Azher T, Fraser I, Mahdavian M, Aaron SD. Population-Based Case-Finding to Identify Subjects with Undiagnosed Asthma or COPD. Eur Respir J. 2020 Jun 18;55(6):2000024. doi: 10.1183/13993003.00024-2020. Print 2020 Jun. Eur Respir J. 2020. PMID: 32299864

  • Barrecheguren M, Pinto L, Mostafavi-Pour-Manshadi SM, Tan WC, Li PZ, Aaron SD, Benedetti A, Chapman KR, Walker B, Fitzgerald JM, Hernande P, Maltais F, Marciniuk DD, O’Donnell DE, Sin DD, Bourbeau J; Identification and Definition of Asthma-COPD Overlap: The CanCOLD Study. Respirology 2020 Feb 16.

  • Makhinova T, Walker BL, Gukert M, Kalvi L, Guirguis LM; Checking Inhaler Technique in the Community Pharmacy: Predictors of Critical Errors.. Pharmacy. 2020 Jan 7;8(1):6.

  • Sharpe H, Claveria-Gonzalez FC, Davidson W, Befus AD, Leung JP, Young E, Walker B;Adult Asthma Diagnosis: Physician Reported Challenges in Alberta-Based Primary Care Practices. Asthma Working Group, Respiratory Health Strategic Clinical Network, Alberta Health Services. SAGE Open Nurs. 2020 May 25;6.

  • Tan WC, Bourbeau J, Aaron SD, Hogg JC, Maltais F, Hernandez P, Marciniuk DD, Chapman KR, To T, Fitzgerald JM, Walker BL, Road J, Zheng L, Zhou G, Yao T, Benedetti A, O’Donnell D, Sin DD. The Effects of Marijuana Smoking on Lung Function in Older People. Eur Respir J. 2019 Dec 19;54(6)

  • Shorofsky M., Bourbeau J., Kimoff R., Jen R., Malhotra A., Ayas N., Tan W., Aaron S., Sin D., Road J., Chapman K., O’Donnell D., Maltais F., Hernandez P., Walker B., Marciniuk K., Kaminska M; Impaired Sleep Quality in COPD is Associated with Exacerbations: The CanCOLD cohort study. CHEST Nov. 2019 156(5):852 10

  • CanCOLD study investigators Aaron SD, Chapman KR, Fitzgerald JM, Hernandez P, Marciniuk DD, Maltais F, O’Donnell DE, Sin D, Walker BL, Paine NJ, Bacon SL, Bourbeau J, Tan WC, Lavoie KL; Psychological Distress is Related to Poor Health Behaviours in COPD and NonCOPD Patients: Evidence from the CanCOLD study.. Respir Med. 2019 Jan;146:1-9.

  • Field SK. Chronic refractory cough: what to do when inhalers, nasal sprays and pills don’t work. CJRCCSM 2018 2018;2(4):194-199 epub. 2018 Oct 22

  • Tan WC, Bourbeau J, Aaron SD, Zhou G, Maltais F, Hernandez P, Fitzgerald JM, Marciniuk DD, Walker B, Sin DD; Global Initiative for Chronic Obstructive Lung Disease 2017 Classification and Lung Function Decline in Chronic Obstructive Pulmonary Disease.. Am J Respir Crit Care Med 2018 Mar 1;197(5):670-673;

  • Dean BW, Birnie EE, Whitmore GA, Vandemheen KL, Boulet L-P, FitzGerald JM, Ainslie M, Gupta S, Lemiere C, Field SK, McIvor RA, Mayers I, Aaron SD. Between visit variability in FEV1 as a diagnostic test for asthma in adults. Annals American Thoracic Society 2018 Sept 1;15(9):1039-46 2018 Jun 7. Doi: 10.1513/Annals ATS 201803-211OC

  • Field SK, Escalante P, Fisher DA, Ireland B, Irwin RS on behalf of the CHEST Expert Cough Panel. Cough due to tuberculosis and other chronic infections: Chest guideline and expert panel report. Chest 2018;153(2):467-497 (2017), doi: 10.1016/j.Chest.2017.11.018

  • Field SK, Conley DP, Paramchuk L, Walker BW, Leigh R. Is there a role for certified respiratory educators in the assessment and management of some chronic cough patients? Primary Health Care: Open Access 2017, 7:1 1000264 DOI: 10.4172/2167-1079.1000264

  • De Sousa Sena R, Ahmed S, Tan WC, Li PZ, Labonte L, Aaron SD, Benedetti A, Chapman KR, Walker B, Fitzgerald JM, Hernandez P, Maltais F, Marciniuk DD, O’Donnell DE, Sin DD, Bourbeau J; Work Productivity Loss in Mild to Moderate COPD: Lessons Learned From the CanCOLD Study. CanCOLD Collaborative Research Group and the Canadian Respiratory Research Network. Eur Respir J. 2017 Sep 12;50(3);

  • Aaron SD, Vandemheen KL, FitzGerald JM, Ainslie M, Gupta S, Lemiere C, Field SK, McIvor RA, Hernandez P, Mayers I, Mulpuru S, Alvarez GG, Pakhale S, Mallick R, Boulet LP. Reevaluation of diagnosis in adults with physician-diagnosed asthma. JAMA 2017;317(3):269-279

  • Peter J Kahrilas, Kenneth Altman, 78. Anne B. Chang, Stephen K. Field, Susan M. Harding, Andrew Lane, Kaiser Lim, Lorcan McGarvey, Jacqueline Smith, and Richard S. Irwin MD, Master FCCP on behalf of the CHEST Expert Cough Panel*. Chronic Cough due to Gastroesophageal Reflux in Adults: CHEST Guideline and Expert Panel Report CHEST 2016;150(6):1341-60

  • Gupta N., Pinto L, Benedetti A, Li P, Tan W, Aaron S, Chapman K, FitzGerald J, Hernandez P, Marciniuk D, Maltais F, O’Donnell D, Sin D, Walker B, and Bourbeau J., The COPD Assessment Test: Can it Discriminate Across COPD Subpopulations? CHEST 2016 Nov; 150(5);