Peak inspiratory flow in Austrian patients with asthma and/or COPD using dry powder inhalers- a cross-sectional,...

Dry powder inhalers (DPIs) prescribed for respiratory diseases require patients to generate sufficient peak inspiratory flow (PIF) for optimal drug delivery to the airways. However, information is scarce regarding PIF of asthma and COPD patients in real-world practice and whether prescribed devices can be properly used.

The observational, non-interventional real-world study PIF NIS included Austrian asthma and COPD patients regularly using a DPI and assessed PIF with the In-Check DIAL G16 inhalation airflow training meter.

The study examined 134 asthma patients (median age 60 years; mostly GINA step 1-3; median ACT score 21) and 123 COPD patients (69 years, mostly GOLD grade 1/2; median CAT score 15). Median PIF was 80 L/min [95% CI 75-90] (asthma) and 70 L/min [95% CI 60-75] (COPD). No asthma patient but six (4.9%) COPD patients failed to reach the minimum PIF required, and 17 (12.7%) asthma and 29 (23.6%) COPD patients did not reach the optimum PIF for their device.

A considerable proportion of asthma and COPD patients does not achieve the optimal PIF for effective drug delivery to the lungs, some even fail to generate the minimal PIF which may lead to undertreatment of their disease. These findings highlight the importance of assessing PIF and suggest that selecting the appropriate inhaler type and proper patient inhaler training might be critical for the adequate inhaled treatment in these patients.