This study utilized the 2020 Health Insurance Review and Assessment Service–National Patient Sample (HIRA-NPS) to examine the prescribing patterns of oral corticosteroids (OCS) among adult patients with asthma in Korea and to systematically evaluate...
This study utilized the 2020 Health Insurance Review and Assessment Service–National Patient Sample (HIRA-NPS) to examine the prescribing patterns of oral corticosteroids (OCS) among adult patients with asthma in Korea and to systematically evaluate differences in healthcare expenditures according to the duration of OCS use. Although OCS are widely employed as an essential therapy for managing acute exacerbations of asthma, long-term or repeated use is associated with a variety of adverse effects, including infections, metabolic disturbances, osteoporosis, and cardiovascular diseases. Prior studies have indicated that cumulative annual exposure exceeding approximately 1,000 mg is linked to a significantly increased risk of such complications; however, quantitative evidence regarding cumulative OCS exposure and its economic burden among Korean asthma patients remains limited.
Among adults aged ≥20 years who received at least one diagnosis of asthma (J45–J46) in 2020, a total of 5,127 individuals had documented OCS prescriptions. These patients were classified into a short-term use group (1–30 days) and a long-term use group (≥90 days), and differences in demographic characteristics, concomitant medication patterns, cumulative OCS exposure, and per-patient-per-month (PPPM) healthcare expenditures were assessed. To accurately capture the duration of OCS exposure, prescriptions separated by ≤14 days were combined into a single treatment episode.
The results demonstrated that patients in the long-term OCS group were older (mean age 61.7 vs. 52.8 years) and had a higher proportion of medical-aid beneficiaries (p<0.001), suggesting greater socioeconomic vulnerability. The mean annual cumulative OCS dose was 1,400 mg in the long-term group, approximately 15-fold higher than the 92 mg observed in the short-term group. This level exceeds the threshold associated with increased risk of adverse outcomes reported in previous studies (around 1,000 mg/year), highlighting the substantial clinical risk associated with prolonged OCS exposure. Furthermore, PPPM healthcare expenditures were approximately 1.7 times higher in the long-term group, with the most pronounced increase observed in non-asthma-related medical costs. This pattern suggests that systemic adverse effects or worsening of comorbid conditions potentially attributable to OCS therapy may drive additional healthcare utilization.
Analysis of concomitant medication patterns revealed that 41.2% of long-term OCS users had no history of inhaled corticosteroid (ICS) prescriptions. This finding indicates a considerable gap between real-world clinical practice and international asthma treatment guidelines, such as GINA, which strongly recommend ICS-based controller therapy. Prolonged OCS use without ICS may contribute to inadequate asthma control and heightened risk of treatment-related complications, underscoring the need for improvements in domestic asthma management practices.
This study is the first to comprehensively characterize OCS prescribing patterns and associated healthcare expenditures among Korean asthma patients using nationwide claims data. Although the use of a single-year cross-sectional dataset constitutes a limitation, the clear evidence of excessive cumulative steroid exposure and elevated medical costs among long-term OCS users holds significant clinical and policy implications. Future research utilizing multi-year longitudinal datasets is warranted to assess the long-term risks of cumulative OCS exposure—including adverse events, increased medical costs, and overall treatment burden—with greater precision. Such evidence would support the development of OCS stewardship strategies, reinforce ICS-based treatment approaches, and inform policy initiatives aimed at reducing steroid dependence. Enhancing access to alternative therapeutic options, including biologics, should also be considered as part of a comprehensive approach to minimizing OCS-related harm.