Measuring Environmental Outcomes Is More Complex Than We Think

OBJECTIVES: Accounting for the environmental impact of healthcare is an important issue. In recent years, there has been a substantial increase in the number of economic evaluations that also report an environmental outcome (usually carbon emissions). However, the true impact of changes in the care pathway is more complex that is currently being reported.

METHODS: A case study comparing two separate surgical devices is used to demonstrate the various consequences of a healthcare decision on the environment. Two devices are compared, with different levels of cost, health outcomes and environmental outcomes.

RESULTS: Patients who receive Device A incur costs of €3,820, compared with €5,410 for Device B. Device A is more effective (121 months of life expectancy compared with 119 for Device B) and is less harmful to the environment (25kg of CO2 emissions, compared with 30kg for Device B). Based on these outcomes, Device A would normally be considered ‘dominant’, since it has better outcomes on all three metrics. However, because Device A results in two additional months of life expectancy, overall CO2 emissions will increase (i.e. including non-healthcare-related emissions). Based on an estimate of 12.7 tons of emissions per year of life, the emissions associated with two additional months would be 2,117kg, vastly outweighing the short-term reduction associated with Device A. In addition, the money saved by Device A will be reinvested into other healthcare, which will increase healthcare emissions by an estimated 0.235kg.

CONCLUSIONS: Measuring the true environmental impact of medicines is complex, and ignoring key indirect consequences could results in suboptimal (or even counter-productive) decisions. Moving healthcare systems towards a net zero target will require wider thinking that simply choosing between individual therapies.