COVID-19 does not impair lung function in kids, adolescents

Covid-19 infection does not appear to affect the lung function of young adults, according to new research presented at the European Respiratory Society International Congress on Tuesday.

The study, by researchers at the Karolinska Institute in Stockholm, Sweden, found that even patients with asthma did not show a statistically significant deterioration in lung function.

However, there was a trend towards slightly lower measurements for the amount of air they could exhale forcibly in one second, known as forced expiratory air volume in one second (FEV1), which is one of the measures of lung function.

"Our analysis showed similar lung function irrespective of Covid-19 history," said Ida Mogensen, a post-doctoral student at Karolinska.

"When we included 123 participants with asthma in the analysis, the 24 per cent who had had Covid-19 tended towards having a slightly lower lung function, but this was not statistically significant," she added.

The team gathered information from 661 young people with an average age 22 years, between October 2020 and May 2021.

Collected data included measurements of lung function, inflammation and white blood cells called eosinophils, which are part of the immune system.

Of the 661 participants, 178 (27 per cent) had antibodies against SARS-CoV-2 indicating they had been infected.

The researchers measured FEV1, FVC (forced vital capacity, which represents the volume of air in the lungs that can be exhaled after a taking the deepest breath possible), and FEV1/FVC ratio, which is an indicator of narrowed airways.

They calculated the changes in lung function between the period before the pandemic and during the pandemic. Then they compared the percentage change with participants who had not been infected.

There was no difference in lung function among patients who had had Covid-19 with respect to eosinophils, indicators of inflammation, allergy responses or use of inhaled corticosteroids.

"These results are reassuring for young adults. However, we will continue to analyse data from more people. In particular, we want to look more closely at people with asthma as the group in this study was fairly small. We are also curious as to whether the length of time after the infection is important, as well as the severity of disease and symptoms," Mogensen said.

In a separate study, presented at the congress on Sunday, researchers showed that the lung function in children and adolescents was mildly impaired only in those who experienced a severe Covid-19 infection.