We aimed to understand predictors of moderate-to-severe asthma exacerbations and high short-acting β2-agonist (SABA) use in adults with asthma newly initiating single-inhaler twice-daily inhaled corticosteroids/long-acting β2-agonists (ICS/LABAs) in England. This non-interventional, longitudinal, retrospective study used medical record data (Clinical Practice Research Datalink Aurum; Hospital Episode Statistics) in England. Eligible patients with diagnosed asthma were ≥ 18 years old 12 months before the first observed single-inhaler twice-daily ICS/LABA prescription date (December 1, 2017-March 31, 2019). Patients were stratified by occurrence of moderate-to-severe exacerbation and SABA use during 12 months' follow-up. Study outcomes included exacerbation occurrence and SABA use. Latent class cluster (LCC) analysis distinguished clusters of predictors with high importance (≥ 0.70) identified from random forest analysis and confirmed on clinical relevance. Treatment characteristics were described within each cluster. Most of 23,567 patients meeting study criteria (80.4%) were white and female (60.3%); mean index age was 50.0 years. Overall, 21 variables were distinguished as key predictors of moderate-to-severe exacerbation (top predictors: comorbid cardiac disease, diabetes, depression, smoking, body mass index BMI) and 22 as key predictors of high SABA use (top predictors: comorbid upper respiratory tract infection, cardiac disease, prior SABA use, age, sex). Five clusters each were observed among patients who experienced an exacerbation and those who did not. Among patients with high or lower SABA use, five and six clusters were observed, respectively. Treatment characteristics were similar across clusters. This study distinguished treatable and non-treatable predictors of exacerbation and high SABA use. Distinct asthma phenotypes were detected via LCC analysis. Distinguished treatable traits including comorbidities, smoking status and BMI, may be targeted by healthcare professionals. Our findings reinforce the importance of personalized asthma treatments with the goal of improving clinical outcomes.
Quint et al. (Tue,) studied this question.