Children With Poorly Controlled Asthma Must Be Prioritised For Covid-19 Vaccine: Study In Lancet

Poorly controlled asthma is a condition in which one has been hospitalised with asthma in the past 2 years, and suffers from symptoms such as chest tightness, shortness of breath, coughing, wheezing.

Representational image of a doctor giving medicine inhalation treatment to a child| Photo: Getty

New Delhi: Children suffering from poorly controlled asthma are at greater risk of Covid-19 hospitalisation compared to those with well-controlled asthma, or non-asthamtic chidren, a new study has found.

Poorly controlled asthma is a condition in which a person has been hospitalised with asthma within the past two years, and suffers from symptoms such as chest tightness, shortness of breath, coughing and wheezing.

The findings of the study were recently published in The Lancet Respiratory Medicine journal. The study is a national analysis and the first-of-its-kind to investigate Covid-19 hospitalisation among children aged five to 17 living in Scotland, United Kingdom. Such children must be prioritised for Covid-19 vaccination, the authors stated in the study.

The study was conducted between March 2020 and July 2021. The findings suggest that current UK recommendations to offer Covid-19 vaccination to all children aged 12 to 17 should be expanded to include children with poorly controlled asthma aged five and older, the study stated. Around 109,488 children aged five and older are estimated to be suffering from poorly controlled asthma.

Children With Asthma Are At Increased Risk Of Serious Covid-19 Outcomes

Prioritsing children for Covid-19 vaccination will help improve vaccine delivery worldwide, the authors stated in the study. This is because an improved vaccine delivery helps reduce the risk of Covid-19 infection, associated illness, and the need for children to take time off school because of falling ill, the authors noted. However, only one in 380 participants with poorly controlled asthma were hospitalised with Covid-19, the study said. 

Professor Aziz Sheikh from the University of Edinburgh, Scotland, said vaccine prioritisation calls for understanding which children with asthma are at increased risk of serious Covid-19 outcomes, according to a Lancet statement. He added that the analysis provides the first national evidence of the risk of Covid-19 hospitalisations among school-aged children suffering from poorly controlled asthma.

The most important implication of the study is that keeping children's asthma under control is critical as it greatly reduces the risk of Covid-19 hospitalisation, and vaccinating children with poorly controlled asthma offers an additional layer of protection from serious Covid-19 outcomes, he said.

Between March 1, 2020, and July 27, 2021, the researchers analysed data from the Scotland-wide Early Pandemic Evaluation and Enhanced Surveillance of Covid-19 (EAVE II) reporting platform, at the request of the UK's Joint Committee on Vaccination and Immunisation (JCVI). The researchers identified which children with asthma were at increased risk of severe Covid-19, leading to hospitalisation within 14 days of a positive RT-PCR test, or death from any cause after a positive test for the SARS-CoV-2 virus, according to the study.

As many as 752,867 children aged five to 17 were included in the analysis. While 8.4 per cent of the participants were diagnosed with asthma, 6.8 per cent had a confirmed SARS-CoV-2 infection, and 1.5 per cent were hospitalised due to Covid-19 infection. The authors were not able to perform a detailed analysis of nine children with most severe outcomes because they had either been admitted to intensive care units (ICU) or had died, the study noted.

As many as 40,231 children did not suffer from asthma but were diagnosed with Covid-19 infection. Of these participants, 382 children were hospitalised with Covid-19, the study said.

548 Covid-19 Hospitalisations Per 100,000 Children Suffering From Poorly-controlled Asthma

The study found that children aged five to 17 with poorly controlled asthma were more likely to be admitted to a hospital due to Covid-19 infection. There were 548 Covid-19 hospitalisations per 100,000 children suffering from poorly-controlled asthma. In children with well-controlled asthma, there were 94 hospitalisations per 100,000 children. There were 54 hospitalisations per 100,000 children without asthma, according to the study.

The researchers also made analyses of the risk of Covid-19 hospitalisation, considering treatment with one or more courses of oral steroids over the past two years. Oral steroids are a medication commonly used to treat asthma attacks. In participants aged five to 17 with uncontrolled asthma who were treated with one course of oral steroids, there were 94 hospitalisations per 100,000 children, while participants with uncontrolled asthma who were treated with two courses had 231 hospitalisations per 100,000 children, the study found. 

Age, sex, socioeconomic status, other illnesses or conditions, and previous non-asthma related hospitalisations are some factors known to be linked with increased risk of serious Covid-19 outcomes. The researchers adjusted for these factors, and found that children who had been recently hospitalised with asthma were six times more likely to be hospitalised due to Covid-19 infection, than those without asthma, the study said.

Also, children who had recently received treatment with oral steroids were three times more likely to be hospitalised than the children without asthma, according to the study.

Over 1 Lakh Kids With Poorly Controlled Asthma In UK May Have Benefitted From Vaccination

During the study period, there were 9,124 children aged five to 17 with poorly controlled asthma in Scotland, who may have benefitted from vaccination, the authors noted in the study. The researchers made an assumption that the prevalence of poorly controlled asthma was same throughout all nations in the UK, and found that there were around 1,09,488 children with poorly controlled asthma in the entire UK may have benefitted from vaccination, the study said.

Dr Ting Shi from the University of Edinburg, who is also a co-author of the study, said their findings highlight the importance of carefully monitoring the children with asthma 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, according to the Lancet statement.

He added that more research was necessary to investigate the underlying mechanisms which increase the risk of Covid-19 hospitalisations in these children.

One of the limitations of the study was that the researchers relied on surrogate markers of recent asthma hospitalisation, or prescription of oral steroids that may not result in accurate identification of children with poorly controlled asthma, the authors noted.

Also, difficulties with access to care over the course of the pandemic may have caused asthma control to change over the two-year study period. The authors also noted that they were unable unable to account for some important factors such as tobacco exposure, unsuitable housing, and ethnicity, which may have influenced the results.