The environmental footprint of healthcare is shaped not only by how medicines are made, but also by how care is delivered. AstraZeneca is launching CARESA, a free tool that helps healthcare professionals model the potential environmental impact of patient care pathways and explore choices that could improve health outcomes for patients and the planet.

Around 40% of healthcare sector emissions come from patient care pathways – from unscheduled visits to their doctor, to emergency services, and hospital-based treatment.  This makes optimising patient care across the healthcare system one of the most significant, yet underexplored opportunities to decarbonise healthcare while improving patient outcomes.

Until now, healthcare practitioners have had limited tools available to measure the environmental impact of early, more integrated care delivery, or to assess the value of new approaches that deliver optimal care for patients for a lower carbon footprint. Few tools provided a standardised way to understand how earlier diagnosis, guideline-directed medical therapy (GDMT) or care closer to the patient’s home could affect the environmental footprint of their care. 

CARESA was developed to close this gap. To date, it has been tested by more than 300 users across 25 countries. The tool's library now holds approximately 250 environmental data points for healthcare activities, providing a robust database for pathway modelling.

Introducing CARESA, a free, open-access tool

CARESA, the CARe pathways Environmental Sustainability Assessment modelling tool, was co-developed by AstraZeneca, Maverex, and Model Health Ltd, with input from the Sustainable Markets Initiative Health Systems Task Force, the Sustainable Healthcare Coalition (SHC), the Centre for Sustainable Healthcare (CSH) and the University of Cambridge. AstraZeneca is now exploring opportunities to transition ownership of CARESA to a public or academic organisation to continue to develop the platform. 

This unique tool translates clinical activities within the care pathway into measurable environmental impacts, calculating:

• Carbon dioxide equivalents (CO₂e)

• Water use 

• Waste

CARESA provides clinicians and decision-makers with evidence at the point of pathway design. It enables stakeholders to compare care pathways and explore how earlier diagnosis, improved disease control and alternative care settings can positively impact patient outcomes and the environmental footprint of healthcare delivery. 

Why this matters

The most sustainable healthcare system is one that keeps people healthier for longer. 

Data shows that healthcare interventions, such as disease prevention, early diagnosis and implementation of GDMT, can simultaneously improve outcomes and deliver reductions in greenhouse gas (GHG) emissions, water use and waste.^2,3,4

This is because better-controlled disease means fewer emergency admissions, fewer unplanned interventions, and a smaller environmental footprint. For example:

• A study of patients with chronic obstructive pulmonary disease (COPD) showed that those with a history of at least two severe exacerbations had GHG emissions related to their future yearly care that were seven times higher compared to those with a history of no exacerbations.²

• A patient with chronic kidney disease (CKD) on dialysis has on average four to eight times higher GHG emissions from care than a patient who is in CKD stage one to four.³

• Data from AstraZeneca’s IMPACT CKD study in eight countries showed that taking steps to lower the number of patients progressing to late-stage CKD can reduce the need for dialysis by 16-53% and reduce the environmental footprint of kidney replacement therapy by 26-49% (through reduced GHG emissions, freshwater consumption and fossil fuel usage) compared to current practice.⁴

With healthcare accounting for around five percent of global GHG emissions, delivering more sustainable care is critical to improve systems resilience and sustainability.⁵

Tested across healthcare settings

Since its beta launch in early 2025, CARESA has been tested by hundreds of users around the world, with the environmental data points in the tool's library now providing a robust database for pathway modelling.

• Denmark: CARESA is supporting a public-private partnership to explore how kidney care could be better coordinated in primary care. Teams from the Herlev Hospital, the Danish Kidney Association and the Capital Region's Climate Committee are using the tool to identify opportunities to improve patient care and reduce environmental impact, supporting the Capital Region’s target to reduce GHG emissions.

• Sweden: Healthcare teams are exploring how to best integrate CARESA to assess the environmental footprint of diagnosis, treatment and monitoring, with the potential of identifying opportunities to redesign care pathways through Sweden's Climate Initiative for the Life Science Sector, a partner network that includes RISE Research Institutes of Sweden.

• UK: CARESA is being incorporated into teaching at the University of Oxford, helping future healthcare professionals and researchers consider the connection between optimised care and environmental impact when planning, evaluating, and delivering healthcare. 

• Uganda: Through a cross-sector collaboration involving Makerere University Lung Institute in Kampala and the Africa Diaspora Centre for Healthy Urban Futures at the Institute of Metabolic Sciences Epidemiology at the University of Cambridge, UK, CARESA is being deployed to map chronic respiratory disease care pathways, including asthma and COPD, and identify opportunities to reduce avoidable travel, waste, resource inefficiencies and associated emissions.

Open access and collaboration

Over 90 governments around the world have committed to building climate resilient and sustainable healthcare systems as part of the WHO Alliance for Transformative Action on Climate and Health (ATACH).⁶

To turn that ambition into action, health systems need evidence.

CARESA is free and publicly available for healthcare organisations, researchers and policymakers to use. We invite stakeholders and partners to use the tool, contribute data and collaborate on studies that strengthen the evidence base for patient-centric and sustainable care.

Veeva ID: Z4-88658
Date of preparation: September 2026