A comparative analysis of errors in inhaler technique among COPD versus asthma patients

This study was designed to evaluate errors in inhaler technique in COPD vs asthma patients and to investigate the association of poor inhaler technique with patient demographics and clinical variables.

A total of 509 adult patients with COPD (n=328) or asthma (n=181) who were currently using an inhaler device were included in this study. Data on patient demographics, duration of disease, type and duration of inhaler therapy, and assessment of inhaler technique were recorded.

Metered dose inhaler (MDI) was the most common type of inhaler used by a similarly high percentage of patients in both COPD (83.2%) and asthma (77.3%) groups. Failure to exhale before inhaling through device (75.8% and 68.5% for MDIs; 73.2% and 71.8% for Aerolizer^®/Handihaler^®; 53.1% and 66.7% for Turbuhaler^®) was the most common error in inhaler technique, in both COPD and asthma groups. Device-specific errors in inhaler techniques were more common in asthma patients as compared with COPD patients, particularly for MDIs (P-values ranged from 0.046 to 0.0005), as associated with female gender (failure to press the buttons on both sides of Aerolizer^®/Handihaler^®, P=0.006), shorter duration of disease (failure to hold MDI or head in a vertical position, P<0.001, and to keep Turbuhaler^® upright, P=0.005), and shorter duration of inhaler usage (failure to hold head in a vertical position during MDI usage, P=0.006, and to keep Turbuhaler^® upright, P=0.012).

In conclusion, our findings revealed that errors in inhaler technique in terms of inhalation maneuvers and device handling were similarly common in COPD and asthma patients. Errors in certain device handling maneuvers, particularly with MDIs, were more common among asthma patients than among COPD patients and associated with female gender and shorter durations of disease and inhaler therapy.