School-age children with severe, poorly controlled asthma were up to six times more likely to be hospitalized with Covid-19 than children without asthma in a Scottish study involving more than 750,000 children.
While the overall risk of becoming seriously ill from Covid-19 was low among children with asthma, the risk was significantly higher for those with a history of hospital admission for asthma or two or more courses of oral corticosteroids after adjustment for relevant confounders.
When previous hospital admission for asthma was used as the marker for uncontrolled asthma, the adjusted hazard ratio for Covid-19 hospitalization was 6.40 (95% CI, 3.27-12.53) among children with poorly controlled asthma and 1.36 (95% CI, 1.02-1.80) among children with well controlled asthma, compared to children without asthma.
The findings, published online Nov. 30 in the journal Lancet Respiratory Medicine, highlight the importance of prioritizing children with poorly controlled asthma for vaccination against Covid-19, noted researcher Aziz Sheikh, MD, of the University of Edinburgh, Edinburgh, U.K., and colleagues.
“Our analysis provides the first national evidence of the risk of Covid-19 hospitalizations among school-aged children with markers of poorly controlled asthma,” Sheikh noted in a written press statement.
“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 hospitalization,” Sheikh added. “Vaccinating those with poorly controlled asthma offers an additional important layer of protection from serious Covid-19 outcomes.”
While previous studies have shown poorly controlled asthma to be a risk factor for severe Covid-19 in adults, a search of the literature by the researchers turned up no studies addressing severe Covid-19 risk among children with varying degrees of asthma severity and control.
“Given that asthma is one of the most prevalent long-term conditions in childhood, in response to a request from [the U.K.’s] Joint Commission on Vaccination and Immunization (JCVI), we sought to investigate the risk of hospital admission from Covid-19 among school-aged children with markers of uncontrolled asthma,” they wrote.
Sheikh and colleagues conducted a national incident cohort study involving all children in Scotland between the ages of 5 and 17 years registered in the linked dataset of Early Pandemic Evaluation and Enhanced Surveillance of Covid-19 (EAVE II) to examine the risk of hospitalization for Covid-19 among children with uncontrolled asthma, identified either by previous hospital admission for asthma or oral steroid prescription during the previous two years.
Adjustments were made for age, sex, socioeconomic status, comorbidity, and previous hospital admission.
Between March 1, 2020, and July 27, 2021, a total of 752,867 children were included in the EAVE II dataset, including 63,463 (8.4%) with clinician-diagnosed-and-recorded asthma.
A total of 6.8% children with asthma had RT-PCR confirmed SARS-CoV-2, and 1.5% were hospitalized with Covid-19. Among children without asthma, 5.8% became infected with SARS-CoV-2 and 0.9% were hospitalized for Covid-19.
Covid-19 hospital admissions were more common among children with poorly controlled asthma than in those with well controlled asthma or those without asthma.
“When using oral corticosteroid prescriptions as the marker of uncontrolled asthma, the adjusted HR was 3.38 (1.84-6.21) for those with three or more prescribed courses of corticosteroids, 3.53 (1.87-6.67) for those with two prescribed courses of corticosteroids, 1.52 (0.90-2.57) for those with one prescribed course of corticosteroids, and 1.34 (0.98-1.82) for those with no prescribed course, compared with those with no asthma,” the study authors wrote.
Based on the markers used in the study, the researchers estimated that roughly 109,000 children in the U.K. should be considered a priority group for vaccination against Covid-19 due to uncontrolled 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,” study co-author Ting Shi, MD, of the University of Edinburgh, noted in a press release.
Study limitations cited by the researchers included the necessary reliance on the chosen surrogate markers of asthma hospitalization and oral steroid use, which may have missed large numbers of children with uncontrolled asthma. The researchers were also unable to adjust for potentially important confounders such as tobacco exposure and ethnicity.
In an accompanying commentary, Rachel Hardwood, MRSC, and Ian Sinha, PhD, of Alder Hey Children’s Hospital, Liverpool, U.K., wrote that while the study did show an increased risk for hospitalization among children with uncontrolled asthma, hospitalization rates were still very low, with just 1.5% of children with asthma and confirmed SARS-CoV-2 infection hospitalized and just nine ICU admissions and/or deaths reported.
“Although children with asthma have been identified as having an increased risk of being admitted to hospital compared with peers without asthma, the overall risk remains very low,” they wrote. “A balance between the risk of hospitalization from SARS-CoV-2 and the low risk of vaccination side effects needs to be carefully considered before vaccination is contemplated.”
“Over the coming winter, many well recognized respiratory viruses are anticipated in children, and in combination with seasonal changes, these are expected to increase the frequency and severity of asthma exacerbations,” they wrote. “A focus on excellent asthma control, including the delivery of the influenza vaccine, and improving air quality and hygiene in schools is essential for all children with asthma to reduce their susceptibility to exacerbations over the coming winter.”
School-age children with severe, poorly controlled asthma were up to six times more likely to be hospitalized with Covid-19 than children without asthma in a national incident cohort study from Scotland.
While the overall risk of becoming seriously ill from Covid-19 was low among children with asthma, the risk was significantly higher for those with a history of hospital admission for asthma or two or more courses of oral corticosteroids.
Salynn Boyles, Contributing Writer, BreakingMED™
This research was funded by the U.K. Medical Research Council, HealthData Research U.K., and the Scottish government.
Cat ID: 190
Topic ID: 79,190,730,933,190,926,100,138,637,192,927,195,929,925,934