Keywords: chronic obstructive lung disease; asthma; carbon footprint; pharmacotherapy

Introduction:

The medical treatment for chronic obstructive pulmonary diseases relies on inhaler therapy. As the propellants used in pressurised metered dose inhalers (pMDI) are powerful greenhouse gases, their environmental impact must be considered.
Scientific societies and national guidelines are increasingly recommending prioritising dry powder inhalers (DPI) over pMDI where appropriate. It is unclear whether these recommendations have already led to a change in prescribing patterns.

Method:

We compared the proportion of DPI for chronic obstructive airway diseases in Germany, Belgium and Slovenia, combining this information with national guideline recommendations. Prescription data from 2013 to 2023 was extracted and clustered by Anatomical Therapeutic Chemical (ATC) code. For each cluster, the proportion of DPI was calculated with respect to all prescribed inhalable drugs. National guidelines were identified via the Guideline International Network and Medline using the MESH terms “Asthma” and “Pulmonary Disease, Chronic Obstructive” with the “guideline” filter.

Results:

Overall, the proportion of DPI on all inhalers decreased from 40–42% to 30–34% between 2014 and 2023 in Germany, Slovenia, and Belgium. A massive reduction in prescribing of anticholinergic mono-preparations could be observed, leading to DPI proportions ranging from 11.8% in Belgium to 42.8% in Germany. In contrast, the proportion of DPI increased for combination therapies involving adrenergics, anticholinergics and corticosteroids. However, the proportions differed between countries, with DPI rates ranging from 42% in Germany to 15% in Belgium and Slovenia. Only one guideline, issued by Germany in 2022, addressed the ecological impact.

Conclusions:

There are relevant differences in the proportion of DPI across several ATC clusters, which highlights the potential for changing prescribing behaviour. Current developments in the proportion of prescribed DPI are not aligned with the need to reduce the healthcare sectors’ carbon footprint.