Until more definitive studies are conducted, it is reasonable to speculate that clinical history (e.g., frequent wheezing and late-onset asthma) [31], indicators of atopy or allergies (e.g., skin testing and higher IgE) [32], physiology (e.g., spirometry, significant bronchodilator response, and air trapping) [33], imaging (e.g., significant bronchial wall thickening in chest computed tomography [CT]), and biomarkers of inflammation (e.g., higher cytokines and higher blood and sputum eosinophils) can be used for COPD with asthma diagnosis [7, 34]. Here, IGHE is linked to allergic disease.