Risk factors for poor adherence to inhaled corticosteroid therapy in patients with moderate to severe asthma
Katsunori Masaki,1,2 Jun Miyata,1,3 Takashi Kamatani,1,4,5 Takae Tanosaki,1,2 Takao Mochimaru,1,2 Hiroki Kabata,1,2 Yusuke Suzuki,6 Koichiro Asano,7 Tomoko Betsuyaku,1 Koichi Fukunaga1,2
Affiliations:
1 Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, Tokyo, Japan
2 Keio Allergy Center, Keio University Hospital, Tokyo, Japan
3 Division of Infectious Diseases and Respiratory Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
4 Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
5 Department of Medical Science Mathematics, Tokyo Medical and Dental University, Tokyo, Japan
6 Department of Respiratory Medicine, Kitasato Institute Hospital, Tokyo, Japan
7 Division of Pulmonary Medicine, Department of Medicine, Tokai University, School of Medicine, Kanagawa, Japan
Abstract
Background: Poor adherence to inhaled corticosteroid (ICS) therapy is a common reason for worsened asthma control.
Objective: We investigated the characteristics of patients with moderate to severe asthma who showed poor adherence to therapy, to identify the barriers for optimal ICS therapy in a real-world observational cohort.
Methods: We enrolled patients aged ≥ 20 years presenting with moderate to severe asthma who were enrolled at 18 hospitals in Japan. According to the Global Initiative for Asthma 2018 steps 3–5, the patients were considered as moderate to severe asthmatic. At inclusion, clinical information was obtained using a self-completed questionnaire. Poor adherence was defined as skipping the ICS therapy for more than once a week or inability to recognize the necessity of daily ICS therapy. Adherence Starts with Knowledge 20 (ASK-20) questionnaire was used to evaluate the cause of therapy incompliance.
Results: Of the total 85 participants, 19 (22%) showed poor adherence. The median age at diagnosis in the poor adherence group was 10.0 years (interquartile range [IQR], 3.0–50.0), and that in the good adherence group was 41.0 years (18.5–51.5; P = 0.050). The scores for the ASK-20 items related to the “resistance to taking too much medicine” and “compliance with the number of dosing” demonstrated statistically significant differences between patients diagnosed with asthma during their childhood and others.
Conclusion: Age at diagnosis is an independent risk factor to predict poor ICS adherence among adults with moderate to severe asthma.
Key words: Adherence, Age at onset, Asthma, Difficult-to-control asthma, Inhaled corticosteroids, Severe asthma, Risk factor,