Greenhouse gas emissions associated with asthma care in the UK: results from SABINA CARBON

Clinical Research Results Abstract Introduction: Poorly-controlled asthma is associated with an increased risk of severe exacerbations and healthcare resource utilisation (HCRU).1,2 The environmental impact of asthma care remains to be quantified. This retrospective cohort study, part of the healthCARe–Based envirONmental cost of treatment (CARBON) program, estimated greenhouse gas (GHG) emissions associated with the management of well-controlled versus poorly-controlled asthma in the United Kingdom (UK).Methods: Patients with asthma (≥12 years) enrolled in the Clinical Practice Research Datalink (2008–2019) were included. Total GHG emissions, measured as carbon dioxide equivalents (CO2e) during first year of follow-up, were estimated for asthma medication use, asthma exacerbations, and asthma-related routine HCRU (general practitioner [GP] and outpatient visits) for patients with asthma classified as well-controlled (<3 short-acting β2-agonist [SABA] canisters/year and no exacerbations at baseline) or poorly-controlled (≥3 SABA canisters/year or ≥1 exacerbation[s]). Excess GHG emissions due to suboptimal asthma control, assessed for all patients, included emissions from ≥3 SABA canister prescriptions, asthma exacerbations, and any GP and outpatient visits within 10 days of hospitalisation or emergency department visit.Results: Of 236,506 patients at baseline, 47.3% had poorly-controlled asthma. When scaled to the UK asthma population,3 the overall carbon footprint of asthma care in the UK was 750,540 tonnes CO2e/year, with excess GHG emissions of 303,874 tonnes CO2e/year contributed by poorly-controlled asthma (Figure 1), which is equivalent to emissions from ~124,000 houses in the UK in 2020.4,5 Poorly-controlled asthma generated ~3-fold higher per capita overall and ~8-fold higher per capita excess carbon footprint versus well-controlled asthma (Figure 2). SABA use accounted for >60% of overall per capita GHG emissions and >90% of excess per capita GHG emissions.Discussion: These findings suggest that addressing the high burden of poorly-controlled asthma by reducing SABA reliance and the risk of exacerbations will significantly reduce the asthma care–related carbon footprint. Research Idea Abstract Service Development & Evaluation Abstract Declaration of Interest The study was designed and funded by AstraZeneca. References and Clinical Trial Registry Information Global Strategy for Asthma Management and Prevention. Global Initiative for Asthma 2021. https://ginasthma.org/wp-content/uploads/2021/05/GINA-Main-Report-2021-V2-WMS.pdfPavord, ID et al. NPJ Prim. Care Respir. Med. 27, 17 (2017). https://doi.org/10.1038/s41533-017-0014-1.Asthma facts and statistics. The Asthma UK and British Lung Foundation Partnership. https://www.asthma.org.uk/about/media/facts-and-statistics/.2020 UK greenhouse gas emissions, provisional figures. Department for Business, Energy and Industrial Strategy. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/972583/2020_Provisional_emissions_statistics_report.pdf (2021).Families and households in the UK: 2020. Office for National Statistics. https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/families/bulletins/familiesandhouseholds/2020 (2021).