Carbon dioxide equivalent emissions and cost impact of non-clinically driven inhaler initiation or switch for COPD

Inhaled medicines are the foundation of respiratory disease care. However, pressurized metered-dose inhalers (pMDI) contain propellants with global warming potential. Efforts to reduce healthcare-related carbon dioxide equivalent (CO₂e) emissions have driven non-clinical switches to dry powder inhalers (DPIs) in some countries, potentially impacting patient outcomes. This study assesses CO₂e emissions and cost impact of non-clinically driven single inhaler triple therapy (SITT) initiation or inhaler switch in patients with chronic obstructive pulmonary disease (COPD) in the UK, Sweden, and Denmark.

A literature review informed a cost and CO₂e budget impact model. Sensitivity analyses explored parameter variations; additional analysis examined expected impact of introducing pMDIs with next-generation propellants (NGPs) from 2026.

Projections of environmentally driven inhaler policies for 2024 - 2028 showed unexpectedly lower CO₂e emission reductions (kgCO₂e) (UK= -15,400,340, Sweden= -824,682, Denmark= -384,683) and increased healthcare costs (in millions) (UK=£563.5; Sweden=€37.4; Denmark=€30.3). Higher CO₂e emissions related to COPD exacerbations offset ∼65 - 70% of anticipated inhaler-related CO₂e savings. Continuing these switch policies after introduction of pMDIs with NGPs completely negated CO₂e savings, resulting in a 12-13-fold increase in total CO₂e emissions.

CO₂e emission savings with non-clinically driven DPI use within the SITT class are offset by increased emissions from poorer clinical control and healthcare use. Prescribing policies/guidelines preferring DPIs over pMDIs for environmental reasons should be updated, recognizing that pMDIs with NGP have a greenhouse gas footprint similar to DPIs. Optimal COPD management through evidence-based guidelines and appropriate inhaler selection is crucial to minimizing carbon footprint and healthcare resource utilization while improving patient outcomes.