Higher risk of Covid-19 hospitalisation among children with poorly controlled asthma, says study

Children with poorly controlled asthma infected with Covid-19 are more likely to require hospitalisation than children with well-controlled asthma or those without asthma, according to a new study. The study, carried out between March 2020 and July 2021, is the first of its kind investigating Covid-19 hospitalisation among 5 to 17-year-olds living in Scotland.

The findings, published in The Lancet Respiratory Medicine journal, suggest that current UK recommendations to offer Covid-19 vaccination to all 12 to 17-year-olds should now be expanded to include children with poorly controlled asthma aged 5 and older — including an estimated 109,488 in the UK.

The authors said that prioritising this group of children for Covid-19 vaccination has important implications for vaccine delivery worldwide by reducing the risk of infection, associated illness and, consequently, the need for children to have time off school. However, the overall risk of children with asthma becoming seriously ill with Covid-19 is low, with 1 in 380 children with poorly controlled asthma in the study hospitalised with Covid-19.

“Understanding which children with asthma are at increased risk of serious Covid-19 outcomes is critical to ongoing policy deliberations on vaccine prioritisation,” said lead author Professor Aziz Sheikh from the University of Edinburgh, Scotland. “Our analysis provides the first national evidence of the risk of Covid-19 hospitalisations among school-aged children with markers of poorly controlled asthma.”

He added, “The key takeaway from this study is that keeping children’s asthma under control is critical as this greatly reduces the risk of Covid-19 hospitalisation. Vaccinating those with poorly controlled asthma offers an additional important layer of protection from serious Covid-19 outcomes.”

Asthma is one the most common long-term childhood conditions affecting an estimated 78 million 5 to 19-year-olds worldwide in 2019, with over 1 million children being treated for asthma in the UK alone. Despite evidence that adults with poorly controlled asthma are at greater risk of being more severely affected by Covid-19, there is a lack of research in children, and until now, there have been no population-based analyses.

At the request of the UK’s Joint Committee on Vaccination and Immunisation (JCVI), researchers analysed data from the Scotland-wide Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) reporting platform between March 1, 2020 and July 27,2021 to identify which children with asthma were at increased risk of severe COVID-19, leading to hospitalisation within 14 days of a positive real-time reverse transcription-polymerase chain reaction (PT-PCR) test, or death from any cause within 28 days after a positive test for SARS-CoV-2. EAVE II allows rapid analysis of data from routinely collected electronic health records and linked national databases for 5.4 million people (around 99% of the Scottish population).

In total, 752,867 children aged 5-17 years old were included in the analysis. Among 63,463 children (8.4%) with a diagnosis of asthma, 4,339 (6.8%) had a confirmed SARS-CoV-2 infection, and 67 (1.5%) of these were admitted to hospital with Covid-19. There were nine intensive care admissions or deaths in children with asthma, which prevented detailed evaluation of these most severe outcomes. Overall, 40,231 (5.8%) of children without asthma had a confirmed SARS-CoV-2 infection, of whom 382 (0.9%) were hospitalised with Covid-19.

The study found that 5-17-year-olds with poorly controlled asthma (defined as being hospitalised with asthma within the past two years) were more likely to be admitted to hospital with Covid-19 (548 Covid-19 hospitalisations per 100,000 children), compared to children with well-controlled asthma (94 hospitalisations per 100,000 children), or without asthma (55 hospitalisations per 100,000 children). Based on these data, the researchers estimate that there were 9,124 children aged 5–17 years old with poorly controlled asthma in Scotland during the study period who might have benefited from Covid-19 vaccination, and approximately 109,488 children in the whole UK.