Mechanism(s) of Airflow Limitation During Exacerbation of Asthma

Summary

The purpose of this study is to evaluate the site and mechanisms responsible for expiratory airflow limitation in chronic, treated, non-smoking, stable asthmatics with moderate to severe persistent expiratory airflow obstruction. Treatment will include inhaled corticosteroids and long acting beta2agonists. The investigators are interested in determining whether the large and/or small airways are the predominant site of airflow limitation. The investigators are also interested in determining whether intrinsic small airways obstruction and/or loss of lung elastic recoil is responsible for expiratory airflow limitation. The investigators are also interested to evaluate the role of varying doses of inhaled corticosteroids to suppress large and small airway inflammation using exhaled nitric oxide as surrogate markers of inflammation. For comparison purposes, spirometry and measurements of exhaled nitric oxide will also be obtained if possible during a naturally occurring exacerbation of asthma.

Timeline

Start

2007-10

Primary completion

2027-06

Completion

2027-06

Publications

• Background Gelb AF, Zamel N. Unsuspected pseudophysiologic emphysema in chronic persistent asthma. Am J Respir Crit Care Med. 2000 Nov;162(5):1778-82. doi: 10.1164/ajrccm.162.5.2001037.
• Background Gelb AF, Licuanan J, Shinar CM, Zamel N. Unsuspected loss of lung elastic recoil in chronic persistent asthma. Chest. 2002 Mar;121(3):715-21. doi: 10.1378/chest.121.3.715.
• Background Gelb AF, Gutierrez CA, Weisman IM, Newsom R, Taylor CF, Zamel N. Simplified detection of dynamic hyperinflation. Chest. 2004 Dec;126(6):1855-60. doi: 10.1378/chest.126.6.1855.
• Background Gelb AF, Flynn Taylor C, Shinar CM, Gutierrez C, Zamel N. Role of spirometry and exhaled nitric oxide to predict exacerbations in treated asthmatics. Chest. 2006 Jun;129(6):1492-9. doi: 10.1378/chest.129.6.1492.
• Background Gelb AF, Taylor CF, Nussbaum E, Gutierrez C, Schein A, Shinar CM, Schein MJ, Epstein JD, Zamel N. Alveolar and airway sites of nitric oxide inflammation in treated asthma. Am J Respir Crit Care Med. 2004 Oct 1;170(7):737-41. doi: 10.1164/rccm.200403-408OC. Epub 2004 Jun 30.
• Background Gelb AF, Zamel N, Krishnan A. Physiologic similarities and differences between asthma and chronic obstructive pulmonary disease. Curr Opin Pulm Med. 2008 Jan;14(1):24-30. doi: 10.1097/MCP.0b013e3282f197df.
• Background Gelb AF, Yamamoto A, Verbeken EK, Schein MJ, Moridzadeh R, Tran D, Fraser C, Barbers R, Elatre W, Koss MN, Glassy EF, Nadel JA. Further Studies of Unsuspected Emphysema in Nonsmoking Patients With Asthma With Persistent Expiratory Airflow Obstruction. Chest. 2018 Mar;153(3):618-629. doi: 10.1016/j.chest.2017.11.016. Epub 2017 Nov 29.
• Results Gelb AF, Moridzadeh R, Singh DH, Fraser C, George SC. In moderate-to-severe asthma patients monitoring exhaled nitric oxide during exacerbation is not a good predictor of spirometric response to oral corticosteroid. J Allergy Clin Immunol. 2012 Jun;129(6):1491-8. doi: 10.1016/j.jaci.2012.03.036. Epub 2012 May 2.
• Results Gelb AF, Yamamoto A, Mauad T, Kollin J, Schein MJ, Nadel JA. Unsuspected mild emphysema in nonsmoking patients with chronic asthma with persistent airway obstruction. J Allergy Clin Immunol. 2014 Jan;133(1):263-5.e1-3. doi: 10.1016/j.jaci.2013.09.045. Epub 2013 Nov 28. No abstract available.
• Results Gelb AF, Singh DH, Moridzadeh R, Fraser C, Tran D, Verbanck S, George SC. Age-stratified comparison of large and peripheral airway/alveolar nitric oxide levels in children and young adults. J Allergy Clin Immunol. 2013 Nov;132(5):1222-4. doi: 10.1016/j.jaci.2013.05.045. Epub 2013 Aug 6. No abstract available.
• Results Senhorini A, Ferreira DS, Shiang C, Silva LF, Dolhnikoff M, Gelb AF, Mauad T. Airway dimensions in fatal asthma and fatal COPD: overlap in older patients. COPD. 2013 Jun;10(3):348-56. doi: 10.3109/15412555.2012.752806. Epub 2013 Mar 28.
• Results Gelb AF, Yamamoto A, Verbeken EK, Nadel JA. Unraveling the Pathophysiology of the Asthma-COPD Overlap Syndrome: Unsuspected Mild Centrilobular Emphysema Is Responsible for Loss of Lung Elastic Recoil in Never Smokers With Asthma With Persistent Expiratory Airflow Limitation. Chest. 2015 Aug;148(2):313-320. doi: 10.1378/chest.14-2483.
• Results Gelb AF, Christenson SA, Nadel JA. Understanding the pathophysiology of the asthma-chronic obstructive pulmonary disease overlap syndrome. Curr Opin Pulm Med. 2016 Mar;22(2):100-5. doi: 10.1097/MCP.0000000000000236.
• Results Gelb AF, Nadel JA. Understanding the pathophysiology of the asthma-chronic obstructive pulmonary disease overlap syndrome. J Allergy Clin Immunol. 2015 Sep;136(3):553-5. doi: 10.1016/j.jaci.2015.06.013. No abstract available.

Drugs

Indications