OBJECTIVES : Asthma exacerbations drive costs and health impacts from asthma. They also cause incremental greenhouse gas (GHG) emissions from transportation, urgent care operations, and use of rescue inhalers. To advance the understanding of GHG emissions associated with asthma, we estimated the carbon footprint and associated costs of asthma exacerbation care by severity level among UK adults.

METHODS : Guidelines for asthma exacerbation treatment in UK adults were reviewed by severity level: mild, moderate, and severe/life-threatening (ATS/ERS definitions). Components of care for each severity were evaluated for GHG emission potential and key drivers were selected. Targeted literature reviews were conducted to quantify the rates of occurrence and carbon dioxide equivalent (CO₂e) emissions per occurrence. Emissions were estimated per exacerbation by severity, and scaled up to the annual UK adult population level based on the annual number of exacerbations at each severity. Costs associated with emissions were based on the UK government’s 2020 non-traded price of carbon, at ₤71 per tonne of CO₂e emissions.

RESULTS : Overall, drivers of emissions for exacerbations were acute care services, transportation, and rescue inhalers. Among UK adults, the annual number of mild, moderate, and severe/life-threatening asthma exacerbations were 118.9M, 5.5M, and 2.4M. This translated to annual carbon footprints of 83,455 tCO₂e, 192,709 tCO₂e, and 448,037 tCO₂e for mild, moderate, and severe/life-threatening exacerbations, respectively. GHG emissions from mild, moderate, and severe/life-threatening exacerbations management were equivalent to GHG emissions from approximately 18,000, 42,000, and 97,000 passenger vehicles driven for one year, respectively. Annual costs of emissions from exacerbation care were ₤5.9M, ₤13.6M, and ₤31.7M for mild, moderate, and severe/life-threatening exacerbations, respectively.

CONCLUSIONS : GHG emissions from asthma exacerbation management are largely driven by care for severe/life-threatening events. Treatment to reduce the severity and occurrence of exacerbations, such as effective, low-emission, long-term control therapy, can help mitigate GHG emissions associated with asthma care.