aHR, adjusted hazard ratio; COPD, chronic obstructive pulmonary disease; EOS, eosinophils; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; IFN, interferon; ILC2, type 2 innate lymphoid cell; ILC3, type 3 innate lymphoid cell; MUC5AC, mucin 5AC; PAS, periodic acid–Schiff;
TGF-β, transforming growth factor beta; TNF, tumor necrosis factor; TSLP, thymic stromal lymphopoietin.
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