Following conversion of these quantitative variables into dichotomic ones, four variables, including female gender, history of allergic rhinitis, serum T-IgE ≥ 69.0 kU/L, and blood eosinophil count ≥ 0.35 × 109/L were found to be independent factors associated with comorbid asthma (β 1.852, OR 6.4, P < 0.001; β 1.070, OR 2.9, P = 0.021; β 2.483, OR 12.0, P < 0.001; β 1.388, OR 4.0, P = 0.001, respectively) (Fig. 3). This evidence concerns the gene IGHE and allergic rhinitis.