Coding for climate: sourcing better climate-health data from medical billing

While evidence points to climate change adversely impacting health and wellbeing, there remains a great need for more authoritative and actionable data that better describes the full magnitude and scope of this growing crisis. Given the uncertainty inherent to current detection and attribution studies, the improved specificity offered by the 10th revision of the International Classification of Diseases (ICD-10) coding of climate-sensitive health outcomes at the point of care may help to better quantify the connection between more intense and frequent extreme weather events and specific health sequela. With improved application of the available ICD-10 codes designed to capture climate-sensitive health outcomes, the ICD-10 system can function as a leading indicator. In this collaboration, publicly available ICD-10 code data was downloaded from Centers for Medicare and Medicaid Services archives and cross-referenced with 29 keywords (e.g. heat, hurricane, smoke, etc) determined by relevance to climate impacts on human health from consensus literature. We identified 46 unique ICD-10 codes for climate-sensitive health conditions. By highlighting the need for broader application of these codes and advocating for the development of new codes that better document the growing burden of climate-sensitive health outcomes, we hope to drive the development of more evidence-based, health-protective interdisciplinary climate action strategies across health systems.