Medical coding systems aren’t well suited for capturing heat-induced morbidity and mortality

Context on the challenge:

“... one of the more complicated aspects of extreme heat is that many of the injuries, illnesses, and deaths from heat exposure come from the exacerbation of underlying cardiovascular, respiratory, or renal conditions, or other indirect impacts. If someone is struck by lightning, the cause of death or injury is obvious. The indirect nature of heat impacts, however, means that while heat is often a significant contributing factor to illness or death, it is rarely cataloged as such. This is because the systems and processes that we have in place for medical coding are not designed to properly consider exposure. They are designed to catalog clinically observable health outcomes. Much of our data on heat-health impacts comes from emergency department visit data. However, when a patient shows up in the emergency department in cardiac distress, emergency physicians are rightfully concentrating on addressing the urgent and life-threatening situation in front of them, not on investigating and determining attribution from external exposures. The job of emergency department personnel is to stabilize the patient. It is the job of other medical professionals, such as a primary care doctor in follow-up visits, to investigate contributing factors. Additionally, the International Classification of Diseases (ICD) coding system — which is used by medical professionals to collect, process, and classify data — is also the mechanism through which a medical provider receives reimbursement from insurance companies for medical services. The ICD is a global collaborative led by the World Health Organization and allows for the tracking of morbidity and mortality across nations. This means that, potentially, the ICD is one of the most powerful tools to properly quantify the impact of climate change on health. The most recent version, ICD-10, includes specific codes for climate exposures; however, these codes (E-Codes, standing for “external cause of injury”) are not tied to reimbursement. Like Z-Codes (which are used to capture social determinants of health, such as homelessness), E-Codes that are not tied to reimbursement are less likely to be incorporated into a patient’s electronic medical records. There is a lack of financial incentive for health systems to promote or require their use. Approximately half of the states in the U.S. have mandated E-Code reporting; however, there is no national reporting requirement. Moreover, in states that do mandate E-Code reporting, the data are often incomplete, missing, or incorrect due to a lack of uniformity in policies across jurisdictions.”[https://www.statnews.com/2023/08/16/extreme-heat-related-deaths-climate-change-estimates/]

Challenges & Prizes

• Climate and Mental Health Award: Uncovering mechanisms between heat and mental health (Funded by Wellcome Trust)

Government Interventions

• Launch statewide assessments of extreme heat impacts

  “You cannot improve what you do not measure. Better tracking of heat-health and economic impacts will allow for state leadership to understand the current impacts and evaluate outcomes from applying different preparedness and mitigation strategies. To establish a baseline, states should initiate a state-wide study of the impacts and costs of extreme heat events. For example, California’s Department of Insurance pioneered a heat-impacts assessment that found that the total impact of seven extreme heat events in the state was $7.7 billion and 460 deaths. Ohio’s Heat Risk Assessment quantified the costs associated with extreme heat for the state. To support this and ongoing evaluation, states will also need to strengthen syndromic surveillance systems to monitor heat-health impacts and sources of risk to public health. Leading examples of heat-health surveillance include Washington State’s Heat Stress Data and New York State’s Heat Surveillance Report. Additional health and wellbeing-related impacts that should be tracked include pregnancy-related outcomes, school closures and student absenteeism, and rises in requests for health-related social needs, like housing” -Alliance for Heat Resilience and Health (AHRH) recommendation¹