Healthcare resource use and costs associated with extreme heat in Alberta, Canada

Heat events are a growing public health concern. There is an opportunity to better characterize how heat events affect healthcare system utilization. We evaluated the heat-related healthcare resource use and costs in Alberta, Canada in the summer of 2021 when record-breaking extreme heat events occurred in the province. We conducted a population-based cohort study using Alberta administrative health data from May to September 2021 to identify and describe patients who used heat-related healthcare resources over this period. Costs were quantified and reported in Canadian dollars (CA$) using 2023 values. 4194 patients used heat-related healthcare resources, including 109 hospitalizations, 1020 ambulatory care visits (99.7% were ED visits), 310 ambulance transfers, and 5555 practitioner claims. Total heat-related healthcare costs were CA$3.2 million. Female sex, age, and a history of myocardial infarction, heart failure, dementia, or diabetes were found to be significantly associated with increased use of heat-related healthcare resources. History of cardiovascular disease (27.1%) or diabetes (12%) were more frequent in patients hospitalized or attended ED (30 and 14.2%, respectively) compared to those who only used outpatient or physician services (26.3 and 11.2%, respectively; all p < 0.05). Heat-related healthcare resource use and costs during the summer of 2021 in Alberta was substantial. Females, older persons, and people with a history of cardiovascular disease were the most affected. This is likely an underestimation of the overall heat impact. Additional research is needed to quantify the broader impact of extreme heat events on the healthcare system and on society.