Examining Pediatric Difficult-to-Treat Asthma in Primary Care Records

Key Takeaways

• In pediatric primary care prescribing records, difficult-to-treat asthma prevalence ranged from 13.1 to 15.7 per 1,000 children across three guideline-based definitions.
• Among children aged 6 to 15 years, annual difficult-to-treat asthma incidence ranged from 4.7 to 7.6 per 1,000.
• High short-acting beta-agonist use, defined as more than 3 canisters annually, was reported in 68% of children with asthma aged 6 to 15 years.

Children whose asthma looks difficult to treat in routine prescribing records may reflect a mix of persistent disease burden, frequent reliever use, and inconsistent controller use rather than one uniform clinical phenotype. A retrospective cohort study examined primary care prescribing records from 2010 to 2020 in children aged 3 to 15 years. 2,364,000 children were included, including 127,921 with asthma.

Investigators operationalized difficult-to-treat asthma (DTTA) with three international guideline-based definitions, high short-acting beta-agonist (SABA) use as more than 3 canisters annually, controller adherence as a medication possession rate above 80%, and National Institute for Health and Care Excellence (NICE) criteria as a prescribing-data screen for possible biologic eligibility.

Estimated burden changed with the definition applied, and prevalence was highest in 2010. Annual DTTA incidence ranged from 4.7 to 7.6 per 1,000 among children with pre-existing asthma, indicating that surveillance outputs varied within the same pediatric population.

Reliever overuse was common among older children in the asthma cohort. Using the NICE-based prescribing screen, 1.6% of children with asthma appeared potentially eligible for biologic therapy before adherence was considered, and only 4% were judged adherent to controller therapy.

The authors treated prescribing data as a way to identify children with potential DTTA rather than confirm diagnosis and cautioned that this approach may overestimate prevalence. The biologic estimate reflects NICE-based screening within prescribing data rather than confirmed specialist eligibility, which limits direct transfer to North American practice settings.

Clinician Questions

How was difficult-to-treat asthma defined in this pediatric prescribing analysis?

Investigators applied three international guideline-based definitions of difficult-to-treat asthma (DTTA) to primary care prescribing data in children aged 3 to 15 years.

What made a child appear potentially eligible for biologic therapy in this pediatric asthma cohort?

Investigators used National Institute for Health and Care Excellence (NICE) criteria to estimate potential biologic eligibility and then assessed controller adherence with a medication possession rate above 80%. This was a prescribing-data screen for potential eligibility rather than a confirmed specialist eligibility decision.

What does high SABA use represent in children with asthma in this dataset?

High short-acting beta-agonist (SABA) use was defined as more than 3 canisters annually among children with asthma aged 6 to 15 years. In this dataset, it functioned as a prescribing-pattern marker reported alongside DTTA surveillance rather than as a standalone confirmation of severe disease.

What can prescribing records show about pediatric difficult-to-treat asthma, and what can they not confirm?

Prescribing data can identify children with potential difficult-to-treat asthma at population scale, but the authors said this approach may overestimate prevalence. Prescribing patterns alone do not confirm a clinical DTTA diagnosis or finalized biologic eligibility.