Abstract

Introduction
Uncontrolled asthma is a known risk factor for asthma-related deaths in children and young people (CYP) and results in significant morbidity and poor quality of life. Temporal trends in uncontrolled asthma in CYP in England remain unknown.

Aim
To describe longitudinal trends in uncontrolled asthma between 2008 and 2019 in CYP in England, stratified by socioeconomic and ethnic groups.

Methods
We conducted a retrospective cohort study using routinely collected linked primary and secondary care data from the Clinical Practice Research Datalink, Hospital Episode Statistics, Office for National Statistics, and the Index of Multiple Deprivation (IMD). We included CYP aged 5-21 with a coded diagnosis of asthma between 2008-2019. We calculated the annual prevalence of uncontrolled asthma, defined by any one of: ≥1 prescription of oral corticosteroids (OCS); prescription of ≥6 bronchodilators; ≥1 asthma exacerbation in primary care; ≥1 visit to Accident & Emergency; or ≥1 asthma hospitalisation per year. We explored the trends through generalised linear model regression and stratified by IMD, ethnicity, region, sex, and age-group.

Results
Mean annual prevalence of uncontrolled asthma was 16.0% (95% CI 15.6–16.7), and the trends remained stable between 2008–2019. The prevalence was highest among children aged 5–11, those from non-white ethnic backgrounds, and those from the most deprived socioeconomic groups. Notably, the gap in prevalence between the most and least deprived widened throughout the study period.

Conclusions
While the overall prevalence of uncontrolled asthma remained stable between 2008 and 2019, children from non-white ethnic backgrounds and the most deprived areas were disproportionately affected. These widening inequalities highlight an urgent need for research into the underlying drivers of disparity and for targeted, equity-focused interventions to reduce the burden of uncontrolled asthma in CYP.