Effects of switching from a metered dose inhaler to a dry powder inhaler on climate emissions and asthma control: post-hoc analysis

Abstract

ObjectiveTo compare the effects of switching from a pressurised metered dose inhaler (pMDI)-based to a dry powder inhaler (DPI)-based maintenance therapy versus continued usual care on greenhouse gas emissions (carbon dioxide equivalents, CO2e) and asthma control.MethodsThis post-hoc analysis was based on a subset of 2236 (53%) patients from the Salford Lung Study in Asthma who at baseline were using a pMDI-based controller therapy. During the study patients were randomised to fluticasone furoate/vilanterol (FF/VI) via the ELLIPTA DPI (switched from pMDI to DPI) (n=1081) or continued their usual care treatment (n=1155), and were managed in conditions close to everyday clinical practice. Annual CO2e (kg) was calculated for the total number of maintenance and rescue inhalers prescribed. Asthma control was assessed by the proportion of ACT responders (composite of ACT total score ≥20 and/or increase from baseline ≥3).ResultsThe groups were well matched for demographic characteristics and baseline Asthma Control Test (ACT) total score (mean age: 49 years; mean ACT score: usual care, 16.6; FF/VI, 16.5). Annual CO2e kg per patient (maintenance plus rescue therapy) was significantly lower with FF/VI DPI treatment (‘switch’ group) than usual care (least squares geometric mean 108 kg (95% CI 102 to 114) vs 240 kg (95% CI 229 to 252), p<0.001). Asthma control was consistently superior over the 12 months in the FF/VI DPI group compared with usual care.ConclusionsPatients switching from a pMDI-based to a DPI-based maintenance therapy more than halved their inhaler carbon footprint without loss of asthma control. The remaining inhaler carbon footprint could be reduced through switches from pMDI to DPI rescue medications or alternative lower-carbon footprint rescue inhalers if available. Asthma control improved in both groups, with greater control demonstrated in those initiated on FF/VI DPI.Trial registration numberNCT01706198.

Climate and Environmental Change

“…For example, in most cases, asthma patients can be safely moved from metered-dose inhalers to dry-powder inhalers, very significantly reducing the total amount of carbon dioxide and other greenhouse gases emitted in asthma management. In Scandinavian countries, 90% of inhalers are now dry-powder, and health outcomes remained the same (Wintemute & Miller, 2020; Woodcock et al, 2022).…”

The environmental impact of inhaler replacement: A carbon footprint and economic calculation of the National Database of Health Insurance Claims in Japan

“…Nonetheless, this study could not assess this aspect due to the limitations of the NDB Open Data, which does not include patient‐specific information. A post‐hoc analysis of a randomized controlled trial on adults showed that switching from ICS/LABA pMDIs to DPIs improved asthma control in those who switched compared to those who remained on pMDIs 26 . Considering the substantial GHG emissions from ICS/LABA pMDIs in Japan, it may be both safe and effective to replace ICS/LABA.…”

Towards net zero: asthma care

“…Encourage practitioner behaviour change to favour DPIs (and SMIs) over pMDIs 1927. A post hoc analysis of 2236 patients in England showed reduced asthma symptoms and greater productivity in daily activities in patients switching from pMDI to DPI 27…”