Impact of nasal polyps on endotype and phenotype in patients with moderate to severe asthma

Abstract

BackgroundNasal polyps (NPs) are a common comorbidity of asthma. Differences in disease endotype and phenotype may have treatment implications for these concomitant conditions, including biologic therapies. ObjectiveTo determine putative differences in type 2 biomarkers, lung function, and asthma control in patients with asthma with NPs (AwNPs) and those with asthma alone (A). MethodsA total of 140 consecutive patients with moderate to severe asthma with or without endoscopic NPs taking a daily inhaled corticosteroid dose of greater than or equal to 800 µg and at least 1 second-line controller were identified from our National Health Service specialist respiratory and rhinology clinics. Data were collected before starting on biologics, including peripheral blood eosinophils (PBEs), fractional exhaled nitric oxide (FeNO), allergy status, spirometry, impulse oscillometry, Asthma Control Questionnaire, oral corticosteroid requiring asthma exacerbations, NP score, and Lund-Mackay score. ResultsThe PBE count and FeNO levels were significantly higher (P < .01), whereas specific and total immunoglobulin E levels (P < .05) were significantly lower in AwNPs vs A. In addition, FeNO had sensitivity of 81% and specificity of 67% for detecting NPs (area under the curve = 0.76; P = .001). Patients with AwNPs had less severe asthma than those with asthma without NPs (A), as reflected by fewer exacerbations (P < .001), lower inhaled corticosteroid dose (P < .001), and less impairment of impulse oscillometry (P < .05). ConclusionPatients with moderate to severe asthma with NPs have higher levels of PBE and FeNO despite better asthma control and lower total and specific allergy than those without NPs.