The Authors: Dr Farah, MBBS FRACP, is a Respiratory and Sleep Physician, Clinical Associate Lecturer at the Sydney Medical School and PhD candidate in the Airway Physiology Group at the Woolcock Institute of Medical Research. Dr Salome, PhD, is a Research Fellow at the Sydney Medical School and Research Leader of the Airway Physiology Group at the Woolcock Institute of Medical Research.
Asthma and obesity: A known association but unknown mechanism
Version of Record online: 23 MAR 2012
© 2011 The Authors. Respirology © 2011 Asian Pacific Society of Respirology
Volume 17, Issue 3, pages 412–421, April 2012
How to Cite
FARAH, C. S. and SALOME, C. M. (2012), Asthma and obesity: A known association but unknown mechanism. Respirology, 17: 412–421. doi: 10.1111/j.1440-1843.2011.02080.x
SERIES EDITOR: AMANDA J. PIPER
- Issue online: 23 MAR 2012
- Version of Record online: 23 MAR 2012
- Accepted manuscript online: 12 OCT 2011 02:15PM EST
- Received 1 September 2011; invited to revise 10 September 2011; revised 14 September 2011; accepted 16 September 2011.
- asthma control;
- body mass index;
- lung mechanics
The obese asthma phenotype is an increasingly common encounter in our clinical practice. Epidemiological data indicate that obesity increases the prevalence and incidence of asthma, and evidence that obesity precedes the development of asthma raises the possibility of a causal association. Obese patients with asthma experience more symptoms and increased morbidity compared with non-obese asthma patients. Despite more than a decade of research into this association, the exact mechanisms that underlie the interaction of obesity with asthma remain unclear. It is unlikely that the asthma–obesity association is simply due to comorbidities such as obstructive sleep apnoea or gastroesophageal reflux disease. Although inflammatory pathways are purported to play a role, there is scant direct evidence in humans that systemic inflammation modulates the behaviour of the asthmatic airway or the expression of symptoms in the obese. The role of non-eosinophilic airway inflammation also requires further study. Obesity results in important changes to the mechanical properties of the respiratory system, and these obesity-related factors appear to exert an additive effect to the asthma-related changes seen in the airways. An understanding of the various physiological perturbations that might be contributing to symptoms in obese patients with asthma will allow for a more targeted and rational treatment approach for these patients.