Alec Thomas (left) and Liz Moore (right)

Health conditions that affect children can have a lifelong impact on them and their families. Understanding why some children develop certain conditions, and how healthcare can best support them, is an important area of research at the University of Liverpool and Alder Hey Children’s Hospital. However, many of the questions that matter most to patients, parents, and healthcare professionals are difficult to answer through traditional research studies alone.

Exploring childhood health through data

Asthma is one of the most common long-term conditions in childhood, and research has shown that children with asthma in the UK have the worst outcomes across Europe. Although asthma itself is well recognised, there are still important questions about its management in children, longer-term effects, and its relationship with other health conditions.

This is where large databases, such as Clinical Practice Research Datalink (CPRD) which contains electronic health records from approximately 18 million people in the UK, can make a real difference.

What is CPRD?

CPRD is a database containing anonymised information that is routinely recorded by GPs in primary care, including diagnoses, prescriptions, referrals, and health measurements. Data from CPRD can be securely linked to other healthcare datasets such as Hospital Episode Statistics (HES).

These linked records allow researchers to study large populations over many years, providing valuable insights into health and disease. By examining healthcare data from thousands or even millions of patients, researchers can investigate patterns and associations that would be difficult, costly, or impossible to study using traditional methods alone.

Understanding asthma and autism

Liz’s research focuses on the relationship between maternal asthma, asthma treatment during pregnancy, and autism spectrum disorder (ASD) in children.

ASD is a neurodevelopmental condition that affects how people communicate, interact socially, and experience the world around them. Researchers have become increasingly interested in whether asthma and ASD may be connected through shared genetic, immune, or inflammatory mechanisms.

Some studies have suggested that asthma may be more common among autistic children, while others have found little evidence of an association. There’s also ongoing uncertainty about whether asthma during pregnancy, or the medications used to treat it, may influence the likelihood of ASD in children.

Using linked mother-child records within CPRD, Liz’s research aims to provide clearer evidence about these questions. By examining asthma diagnoses and asthma treatment during pregnancy alongside later ASD diagnoses in children, Liz hopes to contribute to a better understanding of potential associations and to support better understanding of both conditions for families and healthcare professionals.

Maintaining good asthma control during pregnancy is important for both maternal and child health, and current clinical guidance recommends continuing prescribed asthma treatment. Research that helps clarify the long-term outcomes associated with asthma and its management may help address concerns and provide reassurance for expectant parents.

The value of real-world evidence

One of the strengths of CPRD is its ability to support research across a wide range of health conditions and life stages. The same healthcare records that can be used to study pregnancy and child development can also help researchers investigate other important challenges affecting children’s health.

For example, while Liz’s research examines how maternal asthma may be related to childhood neurodevelopment, Alec is using CPRD data to investigate antibiotic prescribing in young children and the relationship between antibiotic exposure and childhood asthma.

Understanding antibiotic prescribing and asthma

Antibiotics are commonly prescribed to young children in the UK as infections are the most common illnesses they encounter. However, antibiotics are not prescribed equally. There’s evidence showing that people in more deprived areas are prescribed a greater number of antibiotics than those in less deprived areas.

It isn’t clear whether this is because children in poorer areas get more infections or whether there are other factors. This is important as using too many antibiotics can lead to the development of resistant bacteria, stopping them from working in the future. There are also concerns that antibiotic exposure in early life may increase the risk of developing asthma later in childhood.

Alec hopes to use CPRD data to investigate why antibiotic prescribing rates are different between levels of deprivation and whether there’s an association between early-life antibiotic exposure and childhood asthma. This will lead to fairer and safer care for all children.

Looking to the future

Healthcare data provides an opportunity to answer the questions that matter to patients, families, clinicians, and policymakers. By using large-scale real-world evidence, researchers can improve understanding of health conditions, identify opportunities to improve care, and inform future healthcare decisions.

Whether investigating links between maternal asthma and child development or exploring factors that may contribute to antibiotic resistance in children, our shared goal is for our research to ultimately improve children’s health.

Protecting patient privacy

Protecting patient privacy is central to all CPRD research. Data are anonymised before researchers can access them, meaning that identifying information such as names, addresses, and NHS numbers is removed or replaced. Researchers do not have access to information that could directly identify individual patients.

Access to CPRD data is strictly controlled and subject to robust governance processes, ethical oversight, and legal safeguards. Research takes place within secure environments, and findings are reported only in summary form, ensuring that individual patients cannot be identified.