Association between nasal polyposis and T2 airway inflammation in severe asthma

Abstract

Asthma is a heterogenous disease characterized by chronic airway inflammation. Blood eosinophils and fraction of exhaled breath nitric oxide (FeNO) are well-recognized simple tests for T2 airway inflammation commonly assessed in the diagnostic work-up of severe asthma. However, FeNO levels can be elevated in patients with chronic rhinosinusitis, atopy, viral respiratory infections. Very few studies have evaluated the association between nasal polyposis and FeNO levels in patients with severe asthma. <b>Aim:</b> To investigate the potential relationship between nasal polyposis and severe asthma with high levels of FeNO. <b>Methods:</b> We included a group of 72 patients with severe asthma. Medical history, blood eosinophils, Ig E, spirometry, FeNO, asthma control test (ACT), nasal endoscopic examination and CT scan of paranasal sinuses were performed. <b>Results:</b> From the studied group, 32% of patients were diagnosed with nasal polyposis. Compared with patients with severe asthma and without nasal polyposis, those who associated this comorbidity had higher BMI (24.3±4.6 kg/m2 vs. 27.5±5.2 kg/m2, p=0,002) increased levels of eosinophils 4.2±3.6% vs 7.9±4.9%, p=0.001) and high FeNO (33±26 ppb vs. 52±42 ppb, p=0.005). Best predictors for nasal polyposis among patients with severe asthma were eosinophils &gt; 6,5% and FeNO &gt;40 ppb. <b>Conclusions:</b> Increased FeNO and blood eosinophil are useful predictors of nasal polyposis in patients with severe asthma.