Introduction: Inhalation therapy involves two types of adherence: adherence to the drug and adherence to the procedures for the inhalation device. User satisfaction and preference are key factors for maintaining good adherence of both types, and they should be evaluated based on three conditions being well maintained: asthma control level (ACL), adherence, and adequate device operability during usage duration. We compared user satisfaction and preference between a pressurized metered-dose inhaler (pMDI) and a dry powder inhaler (Ellipta), while maintaining the three conditions during usage in stable asthma patients.
Methods: In this open-label, randomized, two-way crossover study, patients with stable asthma [Asthma Control Questionnaire (ACQ) scores < 0.75] were classified into a 20-64-year age group (G1) and a ≥ 65-year age group (G2) and randomly assigned to either a formoterol/fluticasone combination (FFC) as the pMDI group or a vilanterol/fluticasone combination (VFC) as the Ellipta group. Satisfaction and preference levels were evaluated at week 4. ACL was measured using the ACQ and Japan Asthma Control Survey questionnaires at weeks 0 and 4. Device operability and respiratory resistance were also examined.
Results: Forty-four patients (23 G1, age 45.8 ± 1.9 years; 21 G2, 74.1 ± 1.3 years) were enrolled and maintained good ACL during the study. Adherence to FFC pMDI and VFC Ellipta was > 97% in all groups. Device operability did not differ significantly between FFC pMDI and VFC Ellipta in the G1 (p = 0.189) or G2 (p = 0.506) group. Overall satisfaction was marginally higher with the FFC pMDI than with the VFC Ellipta in G2 (p = 0.012) but non-significantly different in G1 (p = 0.733). Factors affecting overall satisfaction in G2 were difference of inhalation device and body mass index. Respiratory resistance did not change significantly over the study in G2.
Conclusion: Based on maintaining good ACL, adherence, and device operability, FFC pMDI showed significantly higher satisfaction and preference levels than VFC Ellipta in elderly persons.
Trial registration: Japan Registry of Clinical Trials identifier, jRCTs041180001 (registered 21 August 2018).
Keywords: Adherence; Asthma; Device operability; Inhalant device; User satisfaction.