Comparison of serious inhaler technique errors made by device-naïve patients using three different dry powder inhalers: a randomised, crossover, open-label study

Abstract

Background: Serious inhaler technique errors can impair drug delivery to the lungs. This randomised, crossover, open-label study evaluated the proportion of patients making predefined serious errors with Pulmojet compared with Diskus and Turbohaler dry powder inhalers.

Methods: Patients ≥18 years old with asthma and/or COPD who were current users of an inhaler but naïve to the study devices were assigned to inhaler technique assessment on Pulmojet and either Diskus or Turbohaler in a randomised order. Patients inhaled through empty devices after reading the patient information leaflet. If serious errors potentially affecting dose delivery were recorded, they repeated the inhalations after watching a training video. Inhaler technique was assessed by a trained nurse observer and an electronic inhalation profile recorder.

Results: Baseline patient characteristics were similar between randomisation arms for the Pulmojet-Diskus (n = 277) and Pulmojet-Turbohaler (n = 144) comparisons. Non-inferiority in the proportions of patients recording no nurse-observed serious errors was demonstrated for both Pulmojet versus Diskus, and Pulmojet versus Turbohaler; therefore, superiority was tested. Patients were significantly less likely to make ≥1 nurse-observed serious errors using Pulmojet compared with Diskus (odds ratio, 0.31; 95 % CI, 0.19-0.51) or Pulmojet compared with Turbohaler (0.23; 0.12-0.44) after reading the patient information leaflet with additional video instruction, if required.

Conclusions: These results suggest Pulmojet is easier to learn to use correctly than the Turbohaler or Diskus for current inhaler users switching to a new dry powder inhaler.

Trial registration: ClinicalTrials.gov Identifier: NCT01794390 (February 14, 2013).

Fig. 1

The Pulmojet inhaler

Fig. 2

Study design showing phases 1 and 2

Fig. 3

Disposition of study patients

Fig. 4

Odds ratio for ≥1 nurse-observed serious errors with Pulmojet relative to Diskus or Turbohaler DPI. (Post-leaflet + video was the primary endpoint.) *Conditional logistic regression (p < 0.001 for all comparisons)

Fig. 5

a. Percentage of patients recording Pulmojet and Diskus errors post-leaflet alone. b. Percentage of patients recording Pulmojet and Diskus errors post-leaflet and instructional video

Fig. 6

a. Percentage of patients recording Pulmojet and Turbohaler errors post-leaflet alone. b. Percentage of patients recording Pulmojet and Turbohaler errors post-leaflet and instructional video