Elevated exhaled nitric oxide is a clinical indicator of future uncontrolled asthma in asthmatic patients on inhaled corticosteroids.

摘要

Asthma is a chronic inflammatory process with airflow obstruction and hyperreactivity; however, diagnosis and monitoring rely on symptoms and lung function and do not routinely include inflammatory markers such as fractional exhaled nitric oxide (Feno). Feno levels >300% of predicted are associated with a high likelihood of a favorable response to inhaled corticosteroids (ICSs) and also worsening asthma with ICS withdrawal. We reported that highest versus lowest quartile Feno levels in asthmatic patients on ICSs were associated with excess short-acting beta_2-ag-onist (SABA) use and exacerbations requiring oral corticosteroid (OCS) courses in a prior year, independent of an asthma control tool and spirometry. We now test the hypothesis that Feno levels >300% predicted identify patients with future uncontrolled asthma, independent of an asthma control tool and spirometry.