More complaints than findings - Long-term pulmonary function in children and adolescents after COVID-19

Knoke, L.; Schlegtendal, A.; Maier, C.; Eitner, L.; Luecke, T.; Brinkmann, F.

Background: The frequency of persistent symptoms after coronavirus disease 2019 (COVID-19) in adults varies from 4.5% to 87%. Pulmonary function can also show long-term impairment in adults: 10% of hospitalised adults had reduced spirometry values, and 24% had decreased diffusion capacity. To date, only preliminary evidence is available on persistent respiratory sequelae in children and adolescents, therefore our objective was to examine the long-term effects of COVID-19 on pulmonary function in this age group. Methods: Multiple-breath washout, body plethysmography, and diffusion capacity testing were performed after an average of 2.6 months (range 0.4-6.0) following COVID-19 in 73 children and adolescents (age 5-18 years) with different disease severity. Cases were compared to 45 controls with and without infection within six months prior to assessment after exclusion of severe acute respiratory coronavirus-2 infection (SARS-CoV-2). Results: Of the 19 patients (27.1%) who complained about persistent or newly emerged symptoms since COVID-19, 8 (11.4%) reported respiratory symptoms. Comparing patients with COVID-19 to controls, no significant differences were detected in frequency of abnormal pulmonary function (COVID-19: 12, 16.4%; controls: 12, 27.7%; OR 0.54, 95% CI 0.22-1.34). Only two patients with persistent respiratory symptoms showed abnormal pulmonary function. Multivariate analysis revealed reduced forced vital capacity (p=0.045) in patients with severe infection regardless of SARS-CoV-2 infection. Discussion: Pulmonary function is rarely impaired in children and adolescents after COVID-19, except of those with severe infection. The discrepancy between persistent respiratory symptoms and normal pulmonary function suggests a different underlying pathology such as dysfunctional breathing.