Correcting Metered-Dose Inhaler Technique vs Switching to Turbohaler in Asthmatic Patients a Study on 'Real-Life' Effectiveness

Abstract

In practice, asthmatic patients whose metered-dose inhaler (MDI) technique is inefficient are either corrected or changed to dry powder breath-actuated or spacer device that is easier to handle. Based on 'real life clinic circumstances', we studied 15 symptomatic asthmatic patients whose MDI techniques were inefficient that either received correction in their technique (n=9) or were changed to turbohaler (n=6). For comparison, we also studied a similar group of symptomatic asthmatic patients (n=6) with appropriate MDI techniques that were treated by doubling of inhaled corticosteroid (ICS) dose. After 4 weeks, FEV(1) and symptom scores in the turbohaler group was significantly improved from baseline but not in the corrected MDI group. The group whose ICS dose was doubled also showed significant improvement in symptom scores but not in FEV(1). We question the benefit gained by correcting MDI technique in some asthmatic patients compared to that of switching over to more user-friendly devices such as turbohaler. In our study, the improvement observed with turbohaler appears to be more than a mere doubling of drug delivery to the lungs and may relate to the recognized greater consistency of drug delivery by turbohaler compared to MDI device.

Keywords: Asthma; metered-dose inhaler; turbohaler.

Figure 1 :

Changes in FEV₁ (% predicted normal) at baseline and 4 weeks after (A) correction of MDI technique (n=9) (B) changing from MDI device to turbohaler in patients with inefficient inhaler technique (n=6) and (C) doubling of inhaled corticosteroid (ICS) dose in patients with appropriate MDI technique (n=6). Horizontal bars represent mean. Connecting lines indicate changes in individual subjects. The change in mean FEV₁ is statistically significant in group whose MDI device was changed to turbohaler.

Figure 2 :

Changes in symptom scores at baseline and 4 weeks after (A) correction of MDI technique (n=9) (B) changing from MDI device to turbohaler in patients with inefficient inhaler technique (n=6) and (C) doubling of inhaled corticosteroid (ICS) dose in patients with appropriate MDI technique (n=6). Horizontal bars represent mean scores. Connecting lines indicate changes in individual subjects. The changes in mean symptom scores are statistically significant in group whose MDI device was changed to turbohaler and group whose ICS dose was doubled.