Disclosed are methods of identifying, predicting and treating subjects at risk for exacerbation or the presence of a respiratory disease, by detecting expression levels of one or more proteins associated with the respiratory disease, wherein said one or more proteins is selected from the group of CCL24, IL2RA, APOA4, GC, IgA, LPA, KLK3 F, FAS, NRCAM, TNFRSFIOC, IL12B, IL23A, RAGE, CCL20, ICAM1, SERPINA7, CDH13 and CDH1, and wherein said respiratory disease may be chronic obstructive pulmonary disease or emphysema.