Objectives: A signal was raised on the safety profile of the inhaled anticholinergic tiotropium and particularly of the new formulation Respimat® (marketed in Italy in mid-2011). Although RCTs comparing the two formulations (Handihaler® and Respimat®) are reassuring, some critical issues require further investigations. This study aims at describing the use of the two formulations in adults and elderly and to examine the prognostic factors for switching from Handihaler® to Respimat® device. Methods: Descriptive study in the Italian Region Umbria during 2011-2012. All residents, with age ≥45 years, who received a prescription of tiotropium were included. Incident users were defined as the users without prescriptions of tiotropium in the previous 6 months; patients who shifted from Handihaler® to Respimat® were considered as switchers. Users of the two formulation were compared with regard to baseline characteristics (including co-morbidities and use of other respiratory drugs). The adjusted OR of receiving Respimat® was estimated for several prognostic factors. Results: Incident users of both formulations (4390 subjects) had similar characteristics. They were older and with more comorbidities than patients included in clinical trials. The probability of switching was greater in patients who received two or more respiratory drugs (up to a maximum among users of ≥ 4 different substances: ORadj 4,62; IC 95% 2,46-8,69) and among users of beta-blockers (ORadj 1,76; IC 95% 1,13-2,75). Age above 75 years and use of lipid-lowering drugs reduced the probability of switching (ORadj 0,52; IC 95% 0,33-0,81 and ORadj 0,68; IC 95% 0,47-0,97). A positive association was also found between neurological conditions and the use of Respimat®. Conclusions: At the beginning of treatment, the choice between the two formulations is not affected by comorbidities and COPD severity. However, these characteristics influence the likelihood of switching. Moreover, tiotropium users in clinical practice are more severe than those included in RCTs.
Characteristics of incident users of tiotropium and predictors of switching between formulations / Rajevic, Maja; F., Trotta; R., Da Cas; M., Rossi; G., Traversa. - (2014). ((Intervento presentato al convegno EuroDURG 2014 tenutosi a UMCG, Groningen, The Netherlands nel 28-29 August 2014.