Abstract
Background
The phenotype of asthma is influenced by age of onset, with late-onset asthmatics showing more obstruction and eosinophilia. Recently, a study (Holguin, 2011) showed that obese asthmatics with early-onset asthma had more airway obstruction, bronchial hyperresponsiveness and exacerbation risk, with no difference in inflammatory markers.
Aim
To evaluate if obesity influences clinical, functional and inflammatory markers in early or late onset severe asthma.
Methods and Results
We studied 73 severe asthmatics (mean age 59.3±11.2 yrs, 65.8% female, 61.6% never smokers; 67.1% atopic) . All patients performed spirometry and collection of sputum for inflammatory cells. Control of asthma was evaluated by Asthma Control Test (ACT) and the exacerbation rate in the last year. The comparison between patients divided in weight class (BMI<25, BMI 25-30 and BMI>30) shows a difference in sputum eosinophilia (median 51.3% vs 12.6% vs 10.4%, p=0.05) and control of symptoms (patients with ACT<19: 27.8% vs 41.4% vs 69.2%, p=0.01).
Conclusions
The body weight influences airway eosinophilia and control of asthma. In early-onset asthmatics, the weight gain seems associated with a reduction of airway eosinophilia, while in late-onset asthmatics the airway eosinophilia is not strongly influenced by body weight, suggesting a different pathogenetic mechanism.
- © 2014 ERS