Clinical phenotypes of asthmatics who require long-term use of tiotropium for asthma control: a real-world study

Abstract

Background: Tiotropium is well tolerated and significantly improve lung function and asthma control as add-on therapy to ICS with or without LABA treatment regardless of baseline characteristics from phase III studies. However, real word studies predicting the long-term need of tiotropium add-on therapy according to clinical phenotypes of asthmatics were limited.

Methods: This retrospective study was conducted at a single medical center from July 2016 to July 2018, and used asthma control test (ACT) to evaluate the effectiveness of tiotropium as add-on therapy in uncontrolled asthmatics. We try to identify the subgroups of asthmatics who need long-term use of tiotropium as a maintenance treatment. The effectiveness is defined as an increased in ACT score > or =3 from baseline after 3 months of tiotropium as add-on therapy. The long-term need of tiotropium is defined as patients required this maintenance drug > 1 year.

Results: A total of 160 uncontrolled asthmatics despite the use of low- or medium - to high-dose of ICS plus LABA were analyzed. There were 112 patients having good response ( ACT score ≧3 points) to tiotropium. Among these patients, subjects were divided into two groups: one was tiotropium adding on therapy > 1 year because patients cannot step down easily; the other was tiotropium adding on therapy < 1 year due to stepping down successfully. All clinical characteristics of these two groups were collected. After univariate and multivariate analysis showed that ACO, initial FEV1 < 80% and BMI >30 were predictors of asthmatics who required long term use of tiotropium.

Conclusions: Athmatics with ACO, initial FEV1 <80%, and BMI >30 required long-term use of tiotropium.