The data from this study once again proves that there is an urgent need for healthcare to reduce its carbon footprint for patients with asthma and COPD, by choosing the right inhaler with low gas emissions. greenhouse is the weakest.
Physicians and the general population are increasingly aware of the environmental risk linked to medications. Concerning respiratory diseases, we now know that pressurized metered dose inhalers containing a propellant gas (pMDI) have a carbon footprint 20 to 40 times greater than that of dry powder inhalers without propellant (DPI). Unfortunately, pMDIs are the most widely used worldwide with considerable differences between countries and regions.
The most commonly used propellants in pMDIs are HFC-134a and HFC-227ea. The latest IPCC report assigns these gases a 100-year global warming potential of 1530 and 3600, respectively. This study aims to provide prescribing physicians with practical information on the use of inhalers to treat chronic airway diseases.
Life cycle analysis of inhalers
Life cycle analysis (LCA) of a drug provides information on its carbon footprint, water use, land use, human toxicity, environmental toxicity. marine environment, etc. LCA data available in Europe in 2020 was combined with inhaler sales data to determine the overall carbon footprint of inhaled medicines as well as the carbon footprint based on the type of inhaler used.
The total greenhouse gas emission linked to the use of pMDIs in Europe for 1 year was estimated at 4.0 Mt (million tonnes) of CO equivalent2. The carbon footprint of salbutamol in pMDI was estimated at 2.1 Mt CO2e.
Influence of asthma treatment strategy
The Global Asthma Initiative (GINA) recently revised its recommendations on asthma treatment. Depending on the stage of the disease, two treatment options are recommended: either LABA/ICS in a single inhaler taken only when needed (route 1), or a maintenance treatment with a low dose of ICS associated with rescue treatment. SABA type (route 2). The diagram below allows you to visualize the carbon footprint of inhalers, depending on the type of inhaler and the treatment regimen used (Figure 1).
Annual carbon footprint (CO2) of different treatment regimens in GINA stage 2 asthma. DPI, dry powder inhaler, ICS, inhalable corticosteroid, pMDI, pressurized metered dose inhaler, SABA, short-acting β-2 agonist.
Reduce carbon footprint by 90%
These data clearly show that switching from pMDI to DPI would significantly reduce the carbon footprint of inhaled treatments. In many countries, rescue SABA is almost exclusively delivered by pMDIs. Switching to salbutamol DPI would reduce the carbon footprint of salbutamol by >90% without impacting asthma control. Switching to a DPI LABA/ICS combination for maintenance and salvage would also reduce the overall carbon footprint by 90%.
It’s time to act
In the absence of a specific medical reason, low carbon inhalers should be offered as the first choice to new patients. On the other hand, any change of inhaler and strategy must be made cautiously, in a measured manner and in consultation with the patient. The data regarding this change comes mainly from studies and not from real life. However, it seems that “switching from pMDI to DPI does not appear to have an impact on exacerbations, adverse drug reactions or respiratory events”.
This article was first published on Mediquality.net
