OBJECTIVE: Asthma medication adherence is of crucial importance for successful disease management. The aim of this study was to identify and rank factors associated with medication adherence among adults with asthma in the general population.

METHODS: We used data on physician-diagnosed asthma, medication adherence, and factors associated with asthma medication adherence from the Danish General Suburban Population Study using a cross-sectional study design. We ranked factors associated with asthma medication adherence based on magnitude of odds ratios, and the population attributable fractions.

RESULTS: Among 20,032 individuals from the general population, 1,128 (6%) suffered from asthma and 822 (73%) of these were adherent to asthma medications. Based on odds ratios, the three top-ranked factors associated with asthma medication adherence were asthma attacks within the past year (4.0; 95% CI: 2.9-5.5), allergy medication use (3.8; 2.6-5.6), and age above median (3.4; 2.4-4.7), followed by asthma severity markers like airway obstruction, and coughing with mucus. Based on population attributable fractions, the three top-ranked factors associated with adherence to asthma medications were asthma attacks within the past year (70%), age above median (57%), and use of allergy medication (49%).

CONCLUSIONS: The study showed that in the general population recent asthma attacks, higher age, and taking allergy medication were the three most important factors associated with asthma medication adherence. The importance of maintaining adherence to asthma medications even in the absence of severe disease or expressed asthma symptoms should be better communicated to the general population.