Single-inhaler triple therapy improves small airway dysfunction in moderate to severe asthma.

Introduction： Single-inhaler triple therapy (SITT) has demonstrated efficacy in uncontrolled asthma patients despite inhaled corticosteroids/long-acting β2 agonists (ICS/LABA) treatment. However, the effects of SITT on small airway dysfunction (SAD) are unknown. <bold>Objective:</bold> To determine the effects of SITT on SAD and the predictors of responsiveness in a retrospective cohort study. <bold>Methods:</bold> Subjects included 30 asthma patients who switched from ICS/LABA to SITT (fluticasone furoate/vilanterol/umeclinidium, mometasone/indacaterol/glycopyrronium, and budesonide/formoterol/glycopyrronium), with spirometry and oscillometry performed before and after switching. SAD parameters included FEF25-75%, R5−R20, X5, Fres, and AX. An increase of at least 3 points in ACT was considered responsive. <bold>Results:</bold> SITT significantly improved FEF25-75%, X5, Fres, and AX as well as FEV1. Fourteen of 27 (52 %) patients were identified as responders to SITT. Responders showed significantly lower ACT and higher R5−R20 than non-responders before SITT (p=0.001 and p=0.004, respectively). Multivariate logistic regression analysis showed that response to SITT was associated with higher R5−R20 before SITT. The ROC analysis of R5−R20 revealed an AUC of 0.791 and a cutoff value of 0.870 (cmH2O/L/s). <bold>Conclusions:</bold> SITT improved SAD, and higher R5−R20 before SITT predicted responsiveness to SITT in moderate to severe asthma patients. Table. Multivariate logistic regression analyses for predicting responders to SITT <table-wrap><object-id>erj;64/suppl_68/PA2116/TB1</object-id><object-id>T1</object-id><object-id>TB1</object-id><table><colgroup><col></col><col></col><col></col><col></col></colgroup><tbody><tr><td></td><td>Adjusted odds ratio</td><td>95% confidence interval</td><td>P-value</td></tr><tr><td>ACT</td><td>0.242</td><td>0.049 to 1.190</td><td>0.080</td></tr><tr><td>History of smoking</td><td>0.173</td><td>0.024 to 1.260</td><td>0.083</td></tr><tr><td>R5−R20 (per 0.01 cmH2O/L/s)</td><td>1.130</td><td>1.010 to 1.260</td><td>0.037</td></tr><tr><td>Fres</td><td>0.526</td><td>0.2070 to 1.340</td><td>0.178</td></tr></tbody></table></table-wrap>