Medication Adherence and Inhaler Use in Patients With Asthma Treated at a Specialized Tertiary Respiratory Hospital in Vietnam

Abstract

Background: Asthma is a common chronic respiratory disease, reducing the quality of life and increasing the mortality risk of patients. Medication adherence and proper inhaler technique play an important role in asthma control. Objective: To investigate medication adherence, inhaler use, asthma control level, and its related factors among asthma outpatients treated at a specialized tertiary respiratory hospital. Methods: A descriptive cross-sectional study was conducted on asthma outpatients treated at the specialized respiratory hospital (April 1, 2022-June 30, 2022). Medication adherence, inhaler use, and asthma control were assessed using the General Medication Adherence Scale, content-validated checklists, and the asthma control test. Data were analyzed using SPSS software, P value of < 0.05 was considered statistically significant.Results: There were 184 patients included (mean age 48.86 ± 13.28, females 53.8%). More than half of the patients had at least one comorbidity (mainly allergic rhinitis). All patients were prescribed inhaled corticosteroid (ICS) and long-acting beta agonist (LABA) as controller medications, and the most prescribed combination was ICS-LABA + leukotriene receptor antagonist (66.8%). The rates of patients with high medication adherence, proper inhaler technique, and good asthma control were 89.6%, 67.4%, and 75.0%, respectively. The higher medication adherence was associated with better asthma control (odds ratio = 4.584, 95% confidence interval 1.633-12.870, P = 0.004). Small sample size and single-center study may limit the generalizability of the results. Conclusions: Medication adherence was generally high, whereas inhaler technique errors remained common. Despite overall favorable asthma control, ongoing inhaler technique counseling and sustained medication adherence remain essential.