Background: Poor adherence to inhaled therapy is common in patients with asthma and COPD. An inhaler selection based on patients' preference could be beneficial to adherence and treatment effectiveness. Properly designed questionnaires can assess patients' satisfaction with their medication devices. The aim of this study was to estimate, using the Feeling of Satisfaction with Inhaler (FSI-10) questionnaire, the ease of use and satisfaction of patients regarding three different marketed dry powder inhalers (DPIs): Diskus(®) (DK), Elpenhaler(®) (EH), and Turbuhaler(®) (TH). The FSI-10 is a self-completed questionnaire to assess patients' opinions regarding ease of use, portability, and usability of devices, irrespective of the drug used.
Patients and methods: We performed a 4-week, open, noninterventional, multicenter, parallel clinical study in 560 asthmatic and 561 COPD patients. During the first visit, patients were classified into three groups according to the DPI they were already using. Patients were regularly receiving their treatments (Seretide DK, Rolenium EH, and Symbicort TH) and agreed to complete the FSI-10 questionnaire in the second visit.
Results: A total of 517 COPD and 523 asthma patients completed the study. All DPIs tested received satisfactory results, while the EH obtained consistently higher scores in the FSI-10 in both COPD and asthma patients (44.7 and 44.1 vs 41.5 and 43 for TH, 40.8 and 41.4 for DK, P<0.001 and P<0.01, respectively). TH was rated better than DK by asthma patients. Patients suffering with severe COPD tended to express higher feeling of satisfaction than those with moderate or mild disease, irrespective of the device used.
Conclusion: All DPIs tested were highly acceptable by asthma and COPD patients of different ages; nevertheless, EH received significantly higher ratings in most of the questionnaire domains. COPD patients in advanced stages of the disease generally expressed higher level of satisfaction with their devices.
Keywords: COPD; FSI-10 questionnaire; asthma; dry powder inhaler; patient satisfaction.