Fig. 2From: Association between plasma interleukin-33 level and acute exacerbation of chronic obstructive pulmonary diseaseRisk of exacerbation in patients with high plasma IL = 33. Model 1: adjusted by age and sex, Model 2: adjusted by age, sex, and FEV1 (%). Abbreviations: IRR, incidence rate ratio; IL, interleukin; FEV1, forced expiratory volume in 1 sBack to article page