Burden and unmet need for specialist care in poorly controlled and severe childhood asthma in a Danish nationwide cohort

Abstract

Background: Asthma is a common disease in childhood and adolescence with lifelong consequences particularly among those at risk of severe disease, poor control and/or frequent exacerbations. Specialist care is recommended for at-risk children and adolescents, yet access to specialist management in free-to-access healthcare settings remains poorly understood.

Methods: A Danish nationwide cohort of children and adolescents aged 2-17 years with persistent asthma, defined as repeated redemption of inhaled corticosteroids (ICS) during 2015, were followed for two years, to identify at-risk children and adolescents comprising those with severe asthma (classified according to GINA 2020 guidelines), poor control (defined as use of 400/600 (ages 2-11/12 +) annual doses of short-acting bronchodilators), or frequent exacerbations (defined as use of oral steroids or hospitalization), and access to specialist care. The population is chosen due to detailed medical records in the setting of universal health care.

Results: The cohort comprised of 29,851 children and adolescents (59% boys), with a median age of 9 years. While 17% of children were on high dose ICS, 22% were on daily ICS below GINA low dose cut-off. Prevalence of severe asthma (3.0-6.5%) was lower than poor asthma control (6.4-25%); both declined from childhood to adolescence. Exacerbations occurred in 7.1-9.0% of children, with median number of exacerbations being 1 (IQR 1-1). Despite being classified as having mild-to-moderate asthma, 15% had poor asthma control and 3.8% experienced exacerbation(s), respectively. While 61% of children with severe asthma and 58% with exacerbation-prone disease were in specialist care, only 24% with uncontrolled disease were receiving specialist care. Of children and adolescents using high-dose ICS, 71% were managed in primary care, while the use of additional controllers was more common in specialist care.

Conclusions: Throughout childhood and adolescence, there was a high prevalence of severe asthma and poor control, although their prevalence declined with age. We demonstrate a large unmet need for specialist care among children with at-risk asthma, particularly among those with poorly controlled asthma, even in a system with free-to-access, tax-funded healthcare.

Keywords: Exacerbations; Paediatric asthma; Population cohort.

Fig. 1

Case identification, treatment intensity and severity assessment in a Danish nationwide cohort of children aged 2–17 years with actively treated asthma

Fig. 2

Venn diagram showing the overlap between clinical phenotypes of uncontrolled asthma, asthma exacerbations and severe asthma in 6424 children aged 2–17 years with actively treated asthma. Note that the diagram only includes the subpopulation of children fulfilling at least one of the criteria above. Uncontrolled asthma was defined as > 400 annual doses of SABA for ages 0–11, > 600 for ages 12 and above, asthma exacerbations was defined as redemption of either 37.5 mg prednisolone for 5 days or hospital admission with asthma. Severe asthma was defined as GINA Step 3 + 4 treated asthma with two moderate or one severe/near-fatal exacerbation(s) for ages 0–11, GINA Step 4 treated asthma with two moderate or one severe/near-fatal exacerbation(s) or GINA Step 5 regardless of exacerbations for ages 12 and above

Fig. 3

Distribution of GINA 2020 treatment steps in a nationwide cohort of 29,851 children aged 2–17 years with actively treated asthma, stratified by age and place of asthma management