Association Between Allergic Conditions and COVID-19 Susceptibility and Outcomes.

Background: The relationship between underlying type 2 in flammation and immune response to COVID-19 is unclear. Objective: To assess the relationships between allergic conditions and COVID-19 susceptibility and outcomes. Methods: In the Optum database, adult patients with and without major allergic conditions (asthma, atopic dermatitis [AD], allergic rhinitis, food allergy, anaphylaxis, or eosinophilic esophagitis) and patients with and without severe asthma/AD were identi fied. Adjusted incidence rate ratios for COVID-19 were compared among patients with vs without allergic conditions or severe asthma/AD vs non -severe asthma/AD during April 1, 2020, to December 31, 2020. Among patients with COVID-19, adjusted hazard ratios (aHRs) of 30 -day COVID-19 -related hospitalization/all-cause mortality were estimated for the same comparisons during April 1, 2020, to March 31, 2022. Results: Patients with (N = 1,273,231; asthma, 47.2%; AD, 1.5%; allergic rhinitis, 58.6%; food allergy, 5.1%; anaphylaxis, 4.1%; eosinophilic esophagitis, 0.9%) and without allergic conditions (N = 2,278,571) were identi fied. Allergic conditions (adjusted incidence rate ratios [95% CI], 1.22 [1.21-1.24]) and asthma severity (1.12 [1.091.15]) were associated with increased incidence of COVID-19. Among patients with COVID-19 (patients with [N = 261,076] and without allergic conditions [N = 1,098,135] were matched on age, sex, region, index month), having an allergic condition had minimal impact on 30 -day COVID-19 -related hospitalization/all-cause mortality (aHR [95% CI] 0.96 [0.95-0.98]) but was associated with a lower risk of mortality (0.80 [0.78-0.83]). Asthma was associated with a higher risk of COVID-19 -related hospitalization/all-cause mortality vs nonasthma allergic conditions (aHR [95% CI], 1.27 [1.25-1.30]), mostly driven by higher hospitalization. Conclusion: Allergic conditions were associated with an increased risk of receiving COVID-19 diagnosis but reduced mortality after infection. (c) 2024 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)