Table 2. Studies including patients with COVID-19 and a history of allergy, asthma, or other atopy-associated diseases.

Study/Reference	Population
Dong et al. [26] (Wuhan, China)	Case series of 11 patients with COVID-19, 3 of them with a history of allergic disease (1 allergic rhinitis, 1 atopic dermatitis, 1 urticaria)
Bhatragu et al. [25](Seattle, WA, USA)	Report of 3 patients taking oral glucocorticosteroids because of breathing difficulties due to COVID-19 and known asthma who were hospitalized 1 week later with acute respiratory insufficiency
Wang et al. [27] (Wuhan, China)	2 of 69 studied patients had asthma
Zhang et al. [8] (Wuhan, China)	Study of 140 patients of whom 2 had chronic urticaria, 1 had asthma, and 10 had unclear adverse drug reactions
Grasselli et al. [29] (Lombardy, Italy)	Study including 1,591, of whom 205 had a history of: bronchial asthma, anemia, inflammatory bowel disease, chronic respiratory insufficiency, endocrine disorders, chronic pancreatitis, diseases of the connective and supporting tissue, organ transplantation, epilepsy, neurological disease (reported as “other” in the study)
Dreher et al. [28] (Aachen, Germany)	Result: COVID-19 patients with a history of respiratory disease develop ARDS more frequently (58 vs. 42%; 14 vs. 11 patients; of these, 4 vs. 2 patients with asthma; n = 50)

ARDS = acute respiratory distress syndrome.