Prevalence of Poorly Controlled Asthma and Factors Associated with Specialist Referral in Those with Poorly Controlled Asthma in a Paediatric Asthma Population

Background: Significant morbidity and mortality are associated with poor asthma control. The aim of this study was to determine factors associated with poor control and referral to specialist secondary care services.Methods: We used primary care data from the Clinical Practice Research Datalink Aurum (CPRD) linked with Hospital Episode Statistics (HES) records from 1st January 2007 to 31st December 2019. We selected patients aged 6-17 years old. Poor control was defined as six or more prescriptions of short-acting beta-agonist (SABA) inhalers, two or more courses of oral corticosteroids (OCS), an Asthma Control test (ACT) or childhood ACT <20, one hospital admission for asthma, or one visit to Accident & Emergency (A&E) department for asthma-related episodes in the 12 months following asthma diagnosis. Asthma severity was defined following GINA guidelines 2021.Results: About 17.6% of children aged between 6 and 17 years with active asthma had poor control. Severe asthma, eczema, food allergies, increased BMI and living in deprived areas were identified as risk factors for poor control. Among those with poor control, referral rates to specialist care were extremely low, only 2% overall. Those with severe asthma were three-times more likely to be referred than those with mild-to-moderate asthma [HRcrude = 4.04 (95% CI, 3.35-4.87); HRadj= 2.72 (95% CI: 2.13-3.49)]. Other factors associated with referral were food allergy and living in a more deprived area.Conclusion: Around 1 in 6 children and adolescents with active asthma are not achieving adequate control of their symptoms. Among the subset of 6-17-year olds with poorly controlled asthma, timely referral for specialist advice in secondary care is rare, especially in those with so-called mild asthma who nevertheless are at significant risk for poor asthma outcomes.