Improving the carbon footprint of medications for cardiovascular disease prevention using fixed dose combinations

Background Healthcare systems are responsible for 4%–5% of the emissions of greenhouse gases worldwide. Fixed dose combination (FDC) medications have demonstrated benefits for patients with CVD including improved adherence, a reduction in CV outcomes and greater cost-effectiveness.[1] However, they remain underutilised. The carbon footprint of FDCs compared to single drug preparations has not been evaluated and may indicate an additional benefit. Purpose To estimate the change in carbon footprint due to increased anti-hypertensive FDC utilisation. Methods The utilisation gap for FDCs amongst patients over 50 years old with hypertension prescribed two or more anti-hypertensive medications was determined from the Irish Longitudinal Study on Ageing (TILDA). The carbon footprint for a standard daily dose of an anti-hypertensive medication, the reduction in CVD related hospital admissions due to anti-hypertensive FDC use as well as the carbon footprint of an average hospital admission have been estimated previously.[1-3] With this information, the reduction in CO2 emissions for a population of one million was estimated. Results For the TILDA cohort, the utilisation gap for anti-hypertensive FDCs was 201,062 individuals per million. The annual carbon footprint of one anti-hypertensive medication was 7.97 kgCO2eq. With the widespread and complete adoption of FDCs, the reduction in emissions was estimated at 1.60 kiloton(kt) CO2eq per million. The reduction in annual hospital admissions and the subsequent reduction in emissions was estimated to be 16.23 ktCO2eq. The total reduction in carbon footprint of FDCs for hypertension was 17.82 ktCO2eq annually. This is comparable to the carbon footprint for 250 transatlantic flights, and a similar reduction is achievable by switching 700,000 incandescent bulbs to LEDs. Conclusions This is the first estimation of the environmental impact of FDCs in the setting of CVD prevention. Further modelling to determine the precision and uncertainty of these estimates will be performed as well as the potential carbon footprint reductions for other FDC medication groups and on a global scale. These findings may impact prescribing practice for CVD prevention and influence patient preference.