[Patient preference in the choice of dry powder inhalers]

To investigate a group of patients' preferences among 3 dry powder inhalers--Accuhaler, Easyhaler, and Turbuhaler--and to analyze the features that were most important for motivating choices.

The study enrolled 30 patients with stable asthma with a mean (SD) age of 40 (13) and who habitually used inhaled corticosteroids. The patients were shown in detail how to use each of the devices and were randomized to begin using them in different orders. After using each inhaler for a week, the patients assessed 9 different features on a scale of 0 to 10 with an independent observer. The patients were asked to put the inhalers in order of preference, and finally to demonstrate they could use them correctly.

All patients correctly performed the inhalation maneuver at the beginning and the end of the study. The mean final scores out of 90 of the 9 features evaluated were 75 (13) for the Easyhaler, 67 (12) for the Accuhaler, and 65 (14) for the Turbuhaler. Differences were statistically significant between the first and the second device (P=0.02) and the first and the third (P=.001) but not between the Accuhaler and the Turbuhaler (P=.376). Mean rating scores were 8.6 (1.4) for the Easyhaler, 7.3 (1.9) for the Turbuhaler, and 7.1 (1.6) for the Accuhaler. The Easyhaler was the first choice for 53% of patients, the Turbuhaler for 27%, and the Accuhaler for 20%.

The Easyhaler was rated the highest by the patients in the study. The scores were a long way from the maximum score, so research into developing an ideal inhaler must continue.