Inhalation technique and asthma outcomes with different corticosteroid-containing inhaler devices.

Objective: Inhaler devices must be used correctly to ensure the effectiveness of the asthma treatment. This study evaluated inhalation technique across different types of corticosteroid-containing inhaler devices as well as health outcomes in patients with asthma. Methods: In a cross-sectional study, we evaluated inhaler technique by observing patients' handling of the inhaler devices and using checklists for four inhaler types, namely Diskus (n = 52), pressure metered dose inhalers (pMDIs; n = 41), Turbuhaler (n = 36) and Twisthaler (n = 16). We also collected data on patients' characteristics, asthma therapy, exacerbations, medication adherence (8-item Morisky Medication Adherence Scale), asthma control (Asthma Control Test) and quality of life (Saint George Respiratory Questionnaire). Results: In total, we included 145 patients. The mean (SD) age of the patients was 54.5 (18.9) years and 57% were female. The majority of the patients (70%) made at least one error in their inhalation technique. Patients using Turbuhaler performed the highest number of elements correctly, followed by pMDIs, Twisthaler and Diskus. Patients with Diskus or Twisthaler had better adherence compared with patients using pMDIs or Turbuhaler. Patients using Twisthaler had better asthma outcomes than patients using the other device types. Conclusions: Most patients with asthma made mistakes when handling their inhaler devices, especially those using Diskus. However, in addition to the device type being used, patients' characteristics, asthma therapy and medication adherence also played an important role in achieving good health outcomes.