IL10 and inflammatory response: In CVA patients, ICS treatment alone for 3 months, 6 months, and 12 months significantly reduced airway hyperresponsiveness, decreased the proportion of eosinophils in sputum, and improved the levels of interleukin‐5 (IL‐5) and IL‐10 in induced sputum, respectively, thereby suggesting that long‐term ICS treatment remained essential to completely eliminate airway inflammation.31