Impact of COVID-19 on Subsequent Lung Function in Childhood: A Systematized Review.

BACKGROUND AND AIMS: The SARS-CoV-2 infection can lead to transiently altered lung function in adults, but data is less clear in children. We aimed to summarize the available evidence about respiratory outcomes after COVID-19 in childhood.

METHODS

We conducted a literature search on post-COVID-19 lung function tests (LFT) on the Medline and Cochrane databases, including studies published between 2019 and 2025.

RESULTS

Three hundred forty-seven publications were identified, and 20 were selected. Results are presented in two sections, based on the duration of follow-up. Most studies included spirometry, whereas many of them presented data from diffusing lung capacity for carbon monoxide, multiple breath nitrogen washout, fractional exhaled nitric oxide, impulse oscillometry, 6-minute walking test, and interrupter resistance. Five papers described no association between COVID-19 and respiratory outcomes, nor a link between the persistence of symptoms and the outcomes. Other authors reported a mild obstructive pattern which showed reversibility post bronchodilators, or a restrictive pattern, particularly when long-COVID was evident. Some papers showed that pulmonary function may be influenced by the initial severity of the SARS-CoV-2 infection.

CONCLUSION

Some studies reported no clear association between lung function impairment and previous history of COVID-19. Other authors reported mild, transient consequences. A small number of papers concluded that severe infection, which is relatively rare in children, might affect pulmonary function. The main limitation of this review was the high heterogeneity of the included studies, especially regarding the COVID-19 severity, the age groups, the LFT details, and the duration of follow-up.