Greenhouse Gas Emissions of Patient Transportation to Kidney Care - A Province-Level Retrospective Cohort Study.

Background: Kidney care has increasingly understood environmental impacts, and patient transportation to care is recognized as one of its largest greenhouse gas (GHG) emissions sources. Objective: Our health region aims to reduce the environmental impact of kidney services while providing equitable care, hence assessment of transportation distances and associated emissions was undertaken. Design: A retrospective observational study was performed to determine round trip and yearly transportation distances from residence to corresponding kidney care setting. Setting: All registered kidney care services throughout British Columbia. Patients: All adult patients in a provincial registry who were receiving scheduled pre-dialysis, conservative management, and home and facility-based dialysis therapies, in 2023. Measurements: Yearly GHG emissions by modality were calculated by multiplying distance travelled by locally sourced emissions factors by vehicle type, then by frequency of care, as defined by local best practices. Methods: Transportation distances and emissions data were reported in median with interquartile range, for a base scenario of travel via gas car, and for four alternate hypothetical emissions lowering scenarios. Results: The cohort included 15,772 adult patients, with distance travelled to care in 2023 exceeding 17 million kilometres, and corresponding annual GHG emissions of 3873 tonnes of carbon dioxide equivalents. Significant variability existed in transportation distance and emissions both within and between care modalities. Home dialysis patients had the longest median round trip distances (and corresponding emissions) for home hemodialysis and peritoneal dialysis of 52.4 and 27.3 kilometres (11.5 and 6.0 kilograms carbon dioxide equivalents, respectively); whereas facility hemodialysis patients had the greatest annual median distances of 2265.2 kilometres and annual emissions of 498.1 kilograms. Combining all transportation to care emissions reductions scenarios resulted in a 62% reduction in GHG emissions. Limitations: Staff transportation was not considered, including that for supported home dialysis modalities, and public transit by light transport vehicle was assumed to follow the most direct road distance from residence to dialysis treatment facility. Conclusions: Patient transportation to kidney therapies in British Columbia has climate change impact considerations, and appropriate use of virtual care, home dialysis therapies, and various low emissions transportation options offer significant improvement opportunities.