Updated on
What did the project achieve?
“Our research has confirmed that preschool children with allergies have an increased likelihood of developing asthma later in childhood – and, for the first time, shown that children without allergies but with bacterial lung infections are also at high risk,” says Professor Sejal Saglani of Imperial College London. “This suggests we need a new, more targeted approach to managing preschool wheeze – which includes testing for bacterial lung infections and treating them effectively to help prevent long-term breathing problems.”
Asthma is the most common long-term medical condition in children in the UK, affecting one in every 11 children.1 Childhood asthma has a lifelong impact on lung health. Many preschool children will experience wheezing attacks – and while most outgrow their symptoms, some will go on to develop asthma at school age.
This project aimed to identify new ways to predict which preschool children who wheeze are most likely to develop asthma – to enable target interventions to help protect long-term lung function.
The team had studied a group of preschool children with severe wheezing, which included a bronchoscopy – a procedure that allowed them to examine their lungs closely for signs of infection and inflammation. At school age, the team invited these children back for further assessment, including questionnaires, lung function tests, allergy skin prick tests, airway samples and blood tests.
“We diagnosed asthma in just over half of children that returned at school age,” says Professor Saglani. “We then compared these outcomes with their pre-school tests – and found that the children who had developed asthma belonged to two groups.”
The first group included children with allergies and elevated numbers of eosinophils – a type of white blood cell associated with allergic responses – in their bloodstream. The second group had no allergies but showed high rates of bacterial and viral infections in the lungs.
“These findings open the possibility of using specific tests to predict which preschool children with wheeze are most likely to develop asthma,” says Professor Saglani. “This could lead to more personalised care, ensuring each child receives the best possible treatment to help protect their lung health as they grow up.”
Skin tests for allergies are already widely used, and the researchers have now shown that blood eosinophils can be measured using a simple finger prick blood test. They also found that just three types of bacteria were responsible for more than 80% of lung infections in wheezing preschoolers.
“We’re now investigating whether nose and throat swabs could be used to detect these bacteria and help us identify children who may benefit from antibiotics,” says Professor Saglani.
The researchers are currently designing a UK-wide clinical trial to evaluate whether managing preschool wheeze based on these new insights can help improve long-term outcomes for children at risk of asthma.
References
- NHS England, Childhood asthma: https://www.england.nhs.uk/childhood-asthma/ [website accessed 09 May 2025]
This research was completed on
Around 1.1 million children in the UK are currently receiving treatment for asthma.[1] Childhood asthma causes a reduction in lung function, which persists into adulthood – affecting their long-term quality of life. Although most pre-school children who wheeze will outgrow their symptoms, some will develop asthma at school age. Professor Sejal Saglani of Imperial College London is aiming to design a new computer-based tool that can predict which young children who wheeze will go on to develop asthma. The long-term goal is to help prevent the condition from developing in children most at risk, reducing the lifelong impact on their lung health.
How are children’s lives affected now?
Asthma is the most common chronic medical condition in children in the UK, affecting one in every 11 children.1 Childhood asthma has a lifelong impact on lung health.
“A child with asthma will cough, wheeze and have breathing difficulties – which can seriously impact on their long-term quality of life,” says Professor Saglani.
Up to half of all children aged between one and five years will suffer from wheezing attacks2 – where they will make a high-pitched whistling noise, mostly when breathing out. Although many will outgrow these symptoms, approximately one in three young children who wheeze will develop asthma by school age.3
“It is important to predict which pre-school children will go on to develop asthma as this could enable early interventions to help prevent the condition from developing,” says Professor Saglani. “But this is challenging as there are several different potential causes for wheezing attacks in young children, including allergies or lung infections.”
How could this research help?
“Our goal is to develop a computer-based tool that can predict which pre-school children who wheeze will continue to have reduced lung function and develop asthma,” says Professor Saglani.
The researchers will assess children who had severe wheezing at pre-school age to find out if they have reduced lung function or asthma at school age. They will also carry out experiments to explore how lung cells from young children who wheeze and school-age children with asthma react to stimuli that can trigger wheezing attacks, such as bacterial infections and allergens.
“We will combine these clinical and biological data and use mathematical modelling to develop a computer-based tool that can predict which young children with wheezing are most likely to develop asthma,” says Professor Saglani.
If successful, their next step would be to design a larger national study to evaluate the accuracy of the new predictive tool.
We hope that this work will ultimately lead to targeted interventions that can help prevent the condition from developing in children most at risk, reducing the lifelong impact on their lung health.
References
- Asthma UK. Asthma facts and statistics. https://www.asthma.org.uk/about/media/facts-and-statistics/ [website accessed 23 February 2021]
- Lowe LA et al. Wheeze phenotypes and lung function in preschool children. Am J Respir Crit Care Med 2005;171(3):231-7.
- Bloom CT et al. Burden of preschool wheeze and progression to asthma in the UK: Population-based cohort 2007 to 2017. Allergy Clin Immunol 2021;147(5):1949–1958.
Research table
Project details
| Project Leader | Professor Sejal Saglani, BSc MBChB MRCPCH MD |
| Location | Inflammation, Repair and Development Section, National Heart and Lung Institute, Imperial College London and Royal Brompton Hospital |
| Project Team |
Dr Reiko Tanaka, PhD
Dr Louise J Fleming, MBChB MRCPCH MD |
| Other Locations | Department of Engineering, Imperial College London |
| Grant Amount | £199,993 |
| Start Date | |
| End Date | |
| Duration | 24 months |
| Grant Code (GN number) | GN2854 |
We do not provide medical advice. If you would like more information about a condition or would like to talk to someone about your health, contact NHS Choices or speak to your GP.