Obesity produces distinct phenotype of asthma
Published Online: July 25, 2011
In an upcoming issue of The Journal of Allergy and Clinical Immunology (JACI), Dixon et al studied asthmatic participants undergoing bariatric surgery. They found that there were important differences between participants with asthma and atopy and those with asthma without evidence of atopy (as assessed by serum IgE). Non-atopic participants were older when first diagnosed with asthma, and after bariatric surgery their airway hyperreactivity improved significantly. In contrast, patients with both asthma and atopy were younger at first asthma diagnosis and although they experienced improvements in asthma control with bariatric surgery, this was not related to changes in airway hyperreactivity. Surprisingly, markers of lymphocytic inflammation were increased after bariatric surgery.
This study suggests that bariatric surgery may improve asthma control, and also has important implications for our understanding of the pathogenesis of asthma in obesity. The results suggest that obesity leads to a distinct phenotype of non-atopic asthma, not associated with allergic airway inflammation, which will improve with weight loss. There are also likely to be important differences in the type of asthma found in obese non-atopic patients with late onset asthma and obese atopic patients with early onset asthma.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.