LAUSR

INTRODUCTION Adherence to medications for asthma and COPD can reduce exacerbation rates, decrease healthcare costs, and improve health-related quality of life. In spite of the advantages to treatment adherence, individuals with asthma and COPD often fail to take medicines as prescribed. The objectives of this study were to determine the extent of non-adherence with asthma and COPD medicines and to describe the reasons for non-adherence in these conditions. MATERIALS AND METHODS Data from the National Health and Wellness Study (NHWS), a self-administered, annual, internet-based cross-sectional survey of US adults from 2018 was used. NHWS participants who self-reported taking daily prescription medication(s) to treat asthma and COPD responded to the 19 reasons for non-adherence and one global item in the Medication Adherence Reasons Scale (MAR-Scale). Frequencies were used to identify the reasons for non-adherence. RESULTS The non-adherence rate in asthma (N = 2810) was 38.4% and 28.4% in COPD (N = 1632). For both conditions, "simply missing the medicine" was the most common cause of non-adherence. Additionally, for both conditions, there was a difference between the non-adherence reason reported by more individuals and the reason for which the medicine was missed for the most number of days. CONCLUSION The MAR-Scale identified the most frequent reasons for non-adherence with asthma and COPD in a nationwide sample in the US. The MAR-Scale can be used as a tool in a clinic setting or at a population level to measure the extent and the reasons for non-adherence.