Asthma control, exacerbations, airway obstruction and reversibility in children before and after SARS-CoV-2 pandemic onset

Background: COVID19 did not demonstrate more frequent or severe disease in asthmatic children, but few is known on its effect on symptoms and lung function. Objectives: To compare asthma symptoms and lung function during first and two last quarters of 2019 with these of 2020. Methods: Retrospective study in asthmatic children seen for lung function assessment. Proportions of children and functional indexes were compared using Chi-2 and t-Student tests, respectively. Results: Distribution of 3419 files across the first, and two last quarters of 2019 and 2020 was 672, 542, 657, and 476, 495 and 577, respectively. Asthma control and exacerbation were quoted in 3166 (92.6%) and 3062 (89.6%) files. Asthma control was similar during the first and third quarters of 2019 and 2020 (P=0.37 and P=0.84, respectively). Total asthma control was more frequently achieved in the last 2020 quarter compared to that of 2019 (75.5% vs 70.3%, P=0.042). Frequency of children with at least one exacerbation in the previous 3 months was higher during first 2020 quarter (59.7% vs 52.4%; P = 0.022) but lower during the two last 2020 quarters (33.3% vs 47.6%, and 44.7% vs 59%, both P Conclusion: Asthma control improved during the first winter after the pandemic onset in line with less airway obstruction or reversibility while exacerbations were more frequent just before the recognition of the epidemic.