Children with poorly controlled asthma up to six times more likely to be hospitalised with Covid, study finds

Poorly controlled asthma in children increases the risk of them requiring hospital treatment once infected with Covid-19, an “urgent analysis” requested by the UK’s Joint Committee on Vaccination and Immunisation has found.

Studying data on all children in Scotland aged between five and 17 years old, researchers found that those prescribed two or more courses of oral steroids for their asthma in the previous two years were three times more likely to be hospitalised with coronavirus than those without asthma.

That increase rose from three to sixfold in children who had recently been hospitalised as a result of their asthma, according to the study published this week in Lancet Respiratory Medicine.

As a result of this “markedly increased risk”, all school-age children with poorly controlled asthma – defined in the study as requiring two courses of steroids or hospitalisation – should be considered a priority for vaccination, the researchers said.

This would translate into 9,124 children across Scotland and an estimated 109,448 children across the UK, the study said.

Currently in the UK, only children above the age of 12 are eligible for vaccination.

Despite the findings of an increased threat, the overall risk of children with asthma becoming seriously ill with coronavirus remains low, with one in 380 children with poorly controlled asthma in the study hospitalised with Covid.

Using Scotland’s national Early Pandemic Evaluation and Enhanced Surveillance of Covid-19 database to analyse the records of more than 750,000 children, the researchers found that, among 63,463 children with a diagnosis of asthma, 4,339 had a confirmed Covid infection between March 2020 and July 2021.

Sixty-nine of these children – or 1.5 per cent – were admitted to hospital.

In contrast, 40,231 children without asthma tested positive for the virus during the same period. Among them, 382 – or 0.9 per cent – required hospital treatment.

Adjusting for factors including age, sex, socioeconomic status, other illnesses or conditions, and previous non-asthma related hospitalisations, the study found that children with well controlled asthma were more likely to avoid hospitalisation with coronavirus than those whose asthma was poorly controlled – in addition to the even greater contrasts with children without asthma.

“Although Covid-19 tends to affect children less severely than adults, our findings underscore the importance of carefully monitoring these children if they become infected with covid-19 and ensuring that children take their preventive inhalers regularly, go for asthma reviews, and have an up-to-date asthma treatment action plan,” said co-author Ting Shi, a research fellow at the University of Edinburgh.

“More research is needed to investigate the underlying mechanisms that predispose children to these increased risks of Covid-19 hospitalisation.”

Lead author Professor Aziz Sheikh, also of the University of Edinburgh, 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.”

In their study, the researchers noted that – amid uncertainty about the benefits and risks of coronavirus vaccines in children, and concerns about limited vaccine supplies in many parts of the world – identifying which school-age children might benefit from earlier doses of coronavirus vaccines could have important implications for vaccine delivery worldwide.

Writing in a linked comment piece, Rachel Harwood, a paediatric surgery registrar at Alder Hey Children’s Hospital in Liverpool who was not involved in the study, warned that “careful decision making” around delivering vaccines to children younger than 12 was “essential”.

Ms Harwood said that despite the increased risk to children without asthma, the overall risk “remains very low”, adding that a balance between this risk and that of vaccine side-effects “needs to be carefully considered before vaccination is contemplated”.