Changes in oral corticosteroid use in asthma treatment -- a 20-year
nationwide drug utilization study
Abstract
Background: Oral corticosteroid use in asthma management can lead to
serious adverse effects, but knowledge on usage trends are limited. We
aimed to investigate this in a nationwide asthma cohort in Denmark from
1999-2018. Methods: By use of Danish nationwide registers, we identified
all young adults (18-45 years) with two or more asthma drug collections
within 12 months since the age of 15 as indicative of active asthma.
Oral corticosteroid use was stratified by exposure level as high use (≥5
mg prednisolone/day) and low use (<5 mg/day) per year, age
groups and gender. Lorenz curves were used to express the skewness of
consumption among users. Results: We identified 318,950 unique
individuals with active asthma during the study period with a median age
of 29 years (interquartile range [IQR] 20-38 years) whereof 57%
were women. The 1-year prevalence of oral corticosteroid users was
stable at 4.8% (median, IQR 4.7%-4.8%), but with a nearly 40%
decrease in high-users from 0.54% in 1999 to 0.33% in 2018. The median
annual dose decreased from 500 mg/y in 1999 to 250 mg/y in 2018. We
found a substantial skewness in the distribution of oral corticosteroid
usage with 10% of users accounting for almost 50% of all oral
corticosteroid use. Conclusions: Although the prevalence of oral
corticosteroid users among young adults with active asthma in Denmark
has been relatively stable from 1999-2018, we observed a decreasing
trend in the prevalence of high-users and annual consumption.