(098) Dispensing Patterns of Inhaled Asthma Medication Before and During COVID-19 Among Young Adults: A Retrospective Inception Cohort Study

Background: The coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on healthcare services, with asthma patients particularly vulnerable due to their reliance on long-term medical monitoring. It remains uncertain whether overall dispensing patterns, such as changes in medication or dosing regimens, have changed for asthma medications during the COVID-19 pandemic.

Objectives: We aimed to identify differences in dispensing patterns between adults who initiated asthma inhalers before the pandemic (cohorts 2014 and 2017) and those who initiated inhalers during the pandemic (cohort 2020).

Methods: This retrospective inception cohort study used the University of Groningen IADB.nl community pharmacy dispensing database. We included individuals aged 16-44 years who initiated inhaled asthma treatment in 2014, 2017, or 2020. Treatment steps were defined as follows: (1) short-acting beta-agonist (SABA) or inhaled corticosteroids (ICS)-formoterol as needed only, (2) low-dose ICS, (3) low-dose ICS + long-acting beta-agonist (LABA) or tiotropium, or medium-dose ICS, (4) medium- to high-dose ICS + LABA or tiotropium, triple therapy, or high-dose ICS, (5) specialist prescriptions or biologics. Time to treatment step switch (step up or step down) and time to first oral prednisolone/prednisone course, were compared between cohorts using Cox regression modeling with a 2-year follow-up.

Results: In 2014, 2017 and 2020, 1,029, 842 and 527 patients initiated asthma inhalers, respectively. In all cohorts, approximately half of the patients initiated treatment at step 1. During the 2-year follow-up, slightly fewer patients switched their treatment steps in cohort 2020 (49% in 2014, 50% in 2017, and 47% in 2020). The time to first switch or first oral prednisolone/prednisone course did not change during the pandemic, nor did the proportion of patients with switch or patients starting oral prednisolone/prednisone courses. From 2014 to 2020, the likelihood of stepping down in treatment steps decreased evenly. The risk for stepping down was significantly lower by 22% in the cohort 2020 (adjusted hazard ratio: 0.78 (95% confidence interval: 0.64 - 0.95), p = 0.012) when compared to the cohort 2014.

Conclusions: During the COVID-19 pandemic, the dispensing patterns of inhaled asthma medications remained consistent with the pre-pandemic period. From 2014 onwards, there was a slight, non-significant, decreasing trend in stepping-down. This trend became statistically significant in 2020, with a 22% reduction in stepping-down.