National Development in the Use of Inhaled Corticosteroid Treatment in Chronic Obstructive Pulmonary Disease: Repeated Cross-Sectional Studies from 1998 to 2018

Recommendations for the treatment of chronic obstructive pulmonary disease (COPD) have shifted towards a more restrictive use of inhaled corticosteroids (ICS). We aimed to identify the nationwide development over time in the use of ICS treatment in COPD. We conducted a register-based repeated cross-sectional study using Danish nationwide registers. On a yearly basis from 1998 to 2018, we included all patients in Denmark >= 40 years of age with an ICD-10 diagnosis of COPD (J44). Accumulated ICS use was calculated for each year based on redeemed prescriptions. Patients were divided into the following groups: No ICS, low-dose ICS, medium-dose ICS, or high-dose ICS. From 1998 to 2018, the yearly proportion of patients without ICS treatment increased (from 50.6% to 57.6%), the proportion of patients on low-dose ICS treatment increased (from 11.3% to 14.9%), and the proportion of patients on high-dose ICS treatment decreased (from 17.0% to 9.4%). We demonstrated a national reduction in the use of ICS treatment in COPD from 1998 to 2018, with an increase in the proportion of patients without ICS and on low-dose ICS treatment and a decrease in the proportion of patients on high-dose ICS treatment.