Participant recruitment

A total of 104 participants (45 healthy participants, 59 AR patients) were enrolled in this study, and the difference of nasal microbial genus was first analyzed using the nasal mucus from 72 participants (30 healthy participants and 42 patients with AR), stratified by sex as 44 men (mean body mass index, 21.8 kg/m²) and 28 women (mean body mass index, 22.3 kg/m²) with a mean age of 32.5 years. Eligible individuals for inclusion in this study included those referred to the Department of Otolaryngology Chung-Ang University College of Medicine from November 2013 to April 2014. Intranasal endoscopy, computed tomography of the paranasal sinus, and AR tests were performed before intranasal sampling; none of the study participants showed signs of upper airway infection. Subjects who had taken any kind of antibiotics 2 months prior; were pregnant or smoker; had diseases and medication histories related to asthma; and/or had any other chronic diseases, such as atherosclerosis, hypertension, arrhythmia, congestive heart failure, diabetes mellitus, osteoporosis, hepatitis, cancer, and autoimmune or neurological diseases, were excluded.

The Institutional Review Board approved the protocol of this study (No. C2013158 [1118]). Study participation was voluntary, and written informed consent was obtained from all participants. The nasal microbial composition at the species level was further analyzed using nasal mucus from 32 participants, stratified as 15 healthy participants (mean age, 34.3 years) and 17 patients with AR (mean age, 37.1 years), who were referred to the Department of Otorhinolaryngology Seoul National University College of Medicine primarily for septal surgery between March 2018 and January 2019 (No. C2012248 [943]). To confirm AR, they underwent a skin prick test or a multiple allergen simultaneous test (MAST) using the Optigen allergen-specific IgE assay system Korean Inhalant Panel (Minaris Medical America, Mountain View, CA, USA) for the detection of allergens and specific IgEs. Among them, 45 subjects were classified into healthy subjects who were negative for all antigens and had no symptoms such as runny nose, nasal obstruction, itching sensation and sneezing. Fifty-nine who were confirmed positive for a specific antigen and showed symptoms of rhinitis were classified as AR subjects.