Carbon Footprints and Life Cycle Assessments of Inhalers: A Review of Published Evidence

Clinical effectiveness and implementation outcomes of pMDI-to-DPI switch in children between 5 and 12 years of age: a scoping review protocol

INTRODUCTION

Inhalers are critical in asthma treatment, and inappropriate inhaler use leads to poor asthma outcomes. In adults and adolescents, dry powder inhalers (DPIs) are safe and effective alternatives to mainstay pressurised metered dose inhalers and could bridge the asthma care gap while also reducing the environmental burden of asthma care. Despite being licensed for use in ages 5 years old and older, the evidence for clinical effectiveness is less clear for patients between ages 5 and 12 years. This protocol describes a scoping review. The primary aim of the review is to identify and synthesise evidence on the clinical effectiveness of DPI use in children aged 5-12 years old with asthma and other wheezing conditions. The secondary aim of the review is to outline the implementation strategies and outcomes supporting the prescribing or switching to DPIs in children.

METHODS AND ANALYSIS

We will conduct a systematic and comprehensive literature search across four electronic databases (Medline, Embase, Cochrane Library and CINAHL) and grey literature. Screening and data extraction will be done independently by two review authors with discrepancies resolved through consensus. Data will be extracted and charted by two independent reviewers, then presented diagrammatically or tabulated with an accompanying narrative summary.

ETHICS AND DISSEMINATION

Ethical approval was not required for this study as it is a scoping review. The results of this scoping review will be submitted to a peer-reviewed scientific journal for publication.

The environmental burden of inhalation

Inhalation systems, mostly metered dose inhalers (MDIs) and dry powder inhalers (DPIs), are currently submitted to a critical assessment for their carbon footprint (CF) and environmental impact. They are related to greenhouse gas (GHG) emissions and they produce waste of used devices with withheld drug residues and unused doses. However, with estimated contributions to anthropogenic GHG-emissions of 0.03 % for MDIs and 0.0012 % for DPIs globally, it may not be expected that mitigating the GHG emissions from inhalers will have a meaningful effect on the current climate change and global warming, notwithstanding that nationally these percentages may be somewhat higher, depending on the ratio of MDIs to DPIs and the total national CF. MDIs are particularly the preferred type of inhalers over DPIs in the USA and UK with ratios of 9: 1 and 7: 3 respectively. In such countries, a partial switch from MDIs to DPIs is to be recommended, providing that such a switch does not jeopardize the therapy. Using renewable energy only for the production and waste management of DPIs will make this type of inhaler almost climate neutral. A greater concern exists about inhaler waste, more particularly about the residual drug and unused doses in discarded devices. Inhalers contribute <0.02 % to global plastic waste annually and most plastic inhalers end in the domestic waste bin and not as litter polluting the environment with plastic. However, they do contain retained drug and unused doses, whereas even full inhalers are disposed. Because globally most municipal waste (70 %) ends up in dumps and landfills, leakage of the drugs into the soil and surface waters is a serious problem. It pollutes drinking water and endangers species and biodiversity. Therefore, a good collection system and an adequate waste management program for used inhalers seems to be the most meaningful measure to take for the environment, as this will stop inhalers and drugs from putting ecosystems at risk.

Driving Sustainability in Asthma and COPD Management: Preventative Models and Green Prescribing in a Rural Primary Care Practice in England

BACKGROUND

Asthma and COPD are among the most prevalent chronic respiratory conditions, with inhalers as their primary pharmacological treatment. In the UK, metered-dose inhalers (MDIs) account for 70% of all inhaler prescriptions and contribute significantly to the NHS's carbon footprint, making green prescribing a critical focus. Aligning environmental sustainability with clinical excellence is essential to reducing exacerbations and deaths while minimising carbon emissions.

OBJECTIVE

This initiative aimed to assess the localised impact of a structured quality improvement program designed to enhance respiratory care and integrate sustainable prescribing practices. Specifically, it sought to evaluate prescribing patterns, respiratory review completion rates, and the feasibility of transitioning patients from MDIs to lower-carbon alternatives whilst maintaining clinical outcomes.

METHODS

The initiative, implemented at a UK general practice in January 2020, focussed on staff education, restructuring respiratory consultations, and patient engagement. The "treatable traits" paradigm and best practice frameworks guided the program to optimise individualised care. Prescribing data, in-date respiratory review rates, and estimated carbon emissions were analysed over 4 years (2020-2024) using publicly available sources such as OpenPrescribing.net. While education was a component of the intervention, no formal assessment was conducted on its direct impact on prescribing behaviours.

RESULTS

The practice achieved an in-date respiratory review rate exceeding 90%, rising to over 96% during the most recent QOF period. Over 4 years, the proportion of non-salbutamol MDI prescriptions decreased from 62.9% to 36.2%, aligning with national sustainability goals. Despite growth in the practice population, overall carbon emissions from inhalers were successfully reduced, reflecting a shift towards lower-carbon prescribing.

CONCLUSION

This initiative illustrates the feasibility of integrating sustainable prescribing practices into routine respiratory care, aligning with the goals of the national health system. This work highlights the potential of local-level interventions to contribute to broader sustainability efforts in respiratory medicine. Improvements in prescribing patterns and review rates have been noted, but more research is needed to evaluate the impact of educational interventions on healthcare providers' and patients' decisions. Future initiatives should focus on structured evaluations of long-term adherence and clinical outcomes.

[Correction to the Article "Recommendations for Reducing the Environmental Impact of Inhalers in Portugal: Consensus Document", Published on Acta Med Port 2024 Sep;37(9):654-661]

N/A.

Clinician and health service interventions to reduce the greenhouse gas emissions generated by healthcare: a systematic review

OBJECTIVE

To synthesise the available evidence on the effects of interventions designed to improve the delivery of healthcare that reduces the greenhouse gas (GHG) emissions of healthcare.

DESIGN

Systematic review and structured synthesis.

SEARCH SOURCES

Cochrane Central Register of Controlled Trials, PubMed, Web of Science and Embase from inception to 3 May 2023.

SELECTION CRITERIA

Randomised, quasi-randomised and non-randomised controlled trials, interrupted time series and controlled or uncontrolled before-after studies that assessed interventions primarily designed to improve the delivery of healthcare that reduces the GHG emissions of healthcare initiated by clinicians or healthcare services within any setting.

MAIN OUTCOME MEASURES

Primary outcome was GHG emissions. Secondary outcomes were financial costs, effectiveness, harms, patient-relevant outcomes, engagement and acceptability.

DATA COLLECTION AND ANALYSIS

Paired authors independently selected studies for inclusion, extracted data, and assessed risk of bias using a modified checklist for observational studies and the certainty of the evidence using Grades of Recommendation, Assessment, Development and Evaluation. Data could not be pooled because of clinical and methodological heterogeneity, so we synthesised results in a structured summary of intervention effects with vote counting based on direction of effect.

RESULTS

21 observational studies were included. Interventions targeted delivery of anaesthesia (12 of 21), waste/recycling (5 of 21), unnecessary test requests (3 of 21) and energy (1 of 21). The primary intervention type was clinician education. Most (20 of 21) studies were judged at unclear or high risk of bias for at least one criterion. Most studies reported effect estimates favouring the intervention (GHG emissions 17 of 18, costs 13 of 15, effectiveness 18 of 20, harms 1 of 1 and staff acceptability 1 of 1 studies), but the evidence is very uncertain for all outcomes (downgraded predominantly for observational study design and risk of bias). No studies reported patient-relevant outcomes other than death or engagement with the intervention.

CONCLUSIONS

Interventions designed to improve the delivery of healthcare that reduces GHG emissions may reduce GHG emissions and costs, reduce anaesthesia use, waste and unnecessary testing, be acceptable to staff and have little to no effect on energy use or unintended harms, but the evidence is very uncertain. Rigorous studies that measure GHG emissions using gold-standard life cycle assessment are needed as well as studies in more diverse areas of healthcare. It is also important that future interventions to reduce GHG emissions evaluate the effect on beneficial and harmful patient outcomes.

PROSPERO REGISTRATION NUMBER

CRD42022309428.

[Recommendations for Reducing the Environmental Impact of Inhalers in Portugal: Consensus Document]

This consensus document addresses the reduction of the environmental impact of inhalers in Portugal. It was prepared by the Portuguese Council for Health and the Environment and the societies representing the specialties that account for these drugs' largest volume of prescriptions, namely the Portuguese Society of Pulmonology, the Portuguese Society of Allergology and Clinical Immunology, the Portuguese Society of Pediatrics, the Portuguese Society of Internal Medicine, the Portuguese Association of General and Family Medicine and also a patient association, the Respira Association. The document acknowledges the significant impact of pressurized metered-dose inhalers on greenhouse gas emissions and highlights the need to transition to more sustainable alternatives. The carbon footprint of pressurized metered-dose inhalers and dry powder inhalers in Portugal was calculated, and the level of awareness among prescribing physicians on this topic was also estimated. Finally, recommendations were developed to accelerate the reduction of the ecological footprint of inhalers.

2023 Canadian Thoracic Society Guideline on Pharmacotherapy in Patients With Stable COPD

Chronic obstructive pulmonary disease patient care must include confirming a diagnosis with postbronchodilator spirometry. Because of the clinical heterogeneity and the reality that airflow obstruction assessed by spirometry only partially reflects disease severity, a thorough clinical evaluation of the patient should include assessment of symptom burden and risk of exacerbations that permits the implementation of evidence-informed pharmacologic and nonpharmacologic interventions. This guideline provides recommendations from a comprehensive systematic review with a meta-analysis and expert-informed clinical remarks to optimize maintenance pharmacologic therapy for individuals with stable COPD, and a revised and practical treatment pathway based on new evidence since the 2019 update of the Canadian Thoracic Society (CTS) Guideline. The key clinical questions were developed using the Patients/Population (P), Intervention(s) (I), Comparison/Comparator (C), and Outcome (O) model for three questions that focuses on the outcomes of symptoms (dyspnea)/health status, acute exacerbations, and mortality. The evidence from this systematic review and meta-analysis leads to the recommendation that all symptomatic patients with spirometry-confirmed COPD should receive long-acting bronchodilator maintenance therapy. Those with moderate to severe dyspnea (modified Medical Research Council ≥ 2) and/or impaired health status (COPD Assessment Test ≥ 10) and a low risk of exacerbations should receive combination therapy with a long-acting muscarinic antagonist/long-acting ẞ2-agonist (LAMA/LABA). For those with a moderate/severe dyspnea and/or impaired health status and a high risk of exacerbations should be prescribed triple combination therapy (LAMA/LABA/inhaled corticosteroids) azithromycin, roflumilast or N-acetylcysteine is recommended for specific populations; a recommendation against the use of theophylline, maintenance systemic oral corticosteroids such as prednisone and inhaled corticosteroid monotherapy is made for all COPD patients.

Smart dry powder inhalers and intelligent adherence management

Adherence to inhaled treatments is a complex challenge for patients with chronic obstructive pulmonary disease (COPD) and asthma, it not only involves following the prescribed treatment plans but also administering the medications correctly. When using a dry powder inhaler (DPI), the inhalation flow is particularly critical. Patients frequently fail to use a rapid enough onset and fast enough inhalation when using DPIs. At the same time, there is increasing pressure on physicians to switch patients to DPIs, to minimise the environmental impact of pMDI propellants. This makes it critical to understand whether a patient will maintain or improve disease control by using their new inhaler correctly. However, it is challenging for health care professionals to understand how a patient behaves away from the clinic. Therefore, it would be beneficial to obtain real-world data through the use of monitoring tools, i.e., "smart inhalers". This paper reviews the technologies used to monitor DPIs, how effective they have been in a clinical setting, and how well these have been adopted by patients and health care providers.