Abstract
The effectiveness of the tiotropium Respimat® formulation in routine clinical practice is still an open issue due to concern about the generalizability of the Tiotropium Safety and Performance in Respimat® (TIOSPIR) trial findings. Our aim was to compare the incidence of acute respiratory events between new users of tiotropium Respimat® and HandiHaler®. The study population comprised patients aged ≥45 years resident in two Italian regions who received a first tiotropium prescription (HandiHaler® or Respimat®) between 1 July 2011 and 30 November 2013. The cohort was identified within the database of drug prescriptions reimbursed by the Italian National Health Service. Clinical outcomes were obtained from hospital records. The primary outcome was the first hospitalization for respiratory events, including chronic obstructive pulmonary disease (COPD) exacerbation, respiratory failure, hypoxemia/hyperventilation and pneumonia, during the exposure period. The hazard ratios were estimated for the propensity score matched groups with Cox regression. After matching, 31,334 patients with incident tiotropium prescriptions were included. Similar incidence rates of the primary outcome between the Respimat® and HandiHaler® users were identified (adjusted hazard ratio 0.95, 95% CI 0.84–1.07). No differences emerged in the subgroup analyses conducted according to the baseline characteristics of the tiotropium users. This study confirms the findings observed in the TIOSPIR trial in a more heterogeneous population that included patient subgroups with severe respiratory disease and unstable COPD.
Acknowledgments
We wish to thank Maja Rajevic (formerly of the “La Sapienza” University of Rome, Italy) and Valentino Conti (formerly of the Lombardy Region, Milan, Italy) for their valuable support during the protocol writing phase.
Author contributions
GT, FT and SSA conceived the study; RDC, MR, MV, GT and FT designed the study; RDC, SSA and FT analyzed the data; and SSA and FT wrote the manuscript. All authors contributed to the discussion and reviewed the manuscript. GT will act as the guarantor of the paper. All authors saw, commented on and approved the final version of the paper.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
Only public employees of the National or Regional Health Authorities were involved in conceiving, planning, and conducting this study. Partial financial support was received from the Umbria Regional Health Authority. The corresponding author had full access to all study data and approved the manuscript for publication.