Uncontrolled asthma in school-aged children-a nationwide specialist care study.

Background: Uncontrolled asthma (UCA) is different from severe asthma and can be identified in children across all ranges of prescribed treatment.

Objective: Our aim was to characterize uncontrolled childhood asthma in pediatric specialist care.

Methods: We performed a nationwide cross-sectional study of 5497 children (aged 6-17 years) with asthma who were treated by pediatricians at outpatient clinics during 2019 and registered in the Swedish National Airway Register. UCA was defined as an Asthma Control Test score of 19 or lower and/or 2 or more exacerbations in the past year and/or an FEV value less than 80% predicted. Treatment was categorized from step 1 to step 5 according to the Global Initiative for Asthma.

Results: UCA was identified in 1690 children (31%), of whom 64% had an Asthma Control Test score of 19 or lower, 20% had recurrent exacerbations, and 31% had an FEV value less than 80% predicted. UCA was associated with female sex (odds ratio [OR] = 1.29 [95% CI = 1.15-1.45]), older age (OR = 1.02 [95% CI = 1.00-1.04]), obesity (OR = 1.43 [95% CI = 1.12-1.83]), and more treatment using steps 1 and 2 as a reference (step 3, OR = 1.28 [95% CI = 1.12-1.46]); steps 4-5, OR = 1.32 [95% CI = 1.10-1.57]). UCA in children prescribed treatment steps 1 and 2 (group UCA1-2) occurred in 28% of all children at this treatment step (n = 887). Children in group UCA1-2 had exacerbations more frequently than did those children with UCA who were prescribed steps 4 and 5 treatment (24% vs 15% [ = .001]).

Conclusion: UCA was common and associated with female sex, increasing age, obesity, and higher Global Initiative for Asthma treatment step. Surprisingly, UCA was also common in children prescribed less than the maximum treatment, and those children could be considered undertreated patients.