Age- and Sex-Stratified Population-Based Estimates of Hospitalization-Requiring Asthma Exacerbation in Korea during Prepandemic Period (2002-2019)

Respiration. 2026 May 7:1-10. doi: 10.1159/000551953. Online ahead of print.

Abstract

Introduction: Asthma exacerbations vary in prevalence, risk factors, and outcomes according to sex and age. However, large-scale longitudinal studies stratifying the prevalence of asthma exacerbation by age and sex are limited.

Methods: This observational national sample cohort study used data from the National Health Insurance database to assess the prevalence of hospitalization requiring asthma exacerbation in Korea in 2002-2019. The study population included 1,137,861 participants, categorized by sex and age. The participants were classified into six age groups: <2 years (infants and toddlers), 2-5 years (preschoolers), 6-12 years (children), 12-18 years (adolescents), 19-59 years (adults), and ≥60 years (older adults). Asthma exacerbation was defined as hospitalization with a primary diagnosis of asthma or status asthmaticus on an annual basis. Trends in annual prevalence were analyzed using joinpoint regression, and the annual average percentage change (AAPC) for each segment was calculated.

Results: Over the entire age range, the prevalence of asthma exacerbation increased from 5.65 cases per 10,000 person-years (PY) in 2002 to 11.89 in 2010 and decreased to 5.73 in 2019. This trend was consistent in male and female individuals. Infants and toddlers, preschoolers, and older adults exhibited the highest prevalence, peaking at 87.14, 84.47, and 22.96 cases per 10,000 PY in 2006-2007, respectively, and subsequently declining. In contrast, the peak incidences in adolescents and adults were 4.76 and 3.26 cases per 10,000 PY, respectively, which were delayed until 2013-2014. During the study period, the AAPC decreased in infants and toddlers as well as preschoolers but increased in age groups after school age, with a dominant increase of 10.7 (from 7.02 to 17.1) noted in adolescents. Mortality due to asthma exacerbation increased significantly among the older population. Among individuals aged under 12 years, asthma exacerbations were more prevalent in male individuals; however, this trend was reversed among adults and older adults, with higher rates observed in female individuals.

Conclusion: This nationwide longitudinal study highlights trends in asthma exacerbation prevalence that vary by sex and age during an 18-year period, indicating the need to tailor asthma exacerbation prevention strategies in response to these changes.

Keywords: Asthma exacerbation; Population-based prevalence; Temporal trends.