Effect of extreme heat on fall risk in older adults in a rural state

Background: Falls are common in older adults and may result in decreased functional ability, hospitalization, and death. Extreme temperature events, expected to worsen as a result of changing climates, have systemic impacts on the body, many of which overlap with the risk factors for falls in older adults. Our objective was to quantify the association between temperatures of 32°C (90°F) and greater and fall risk in older adults in a rural population. Methods: We analyzed emergency medical services (EMS) patient care report data (2019–2023, n = 26,266) and hospital discharge data (emergency department visits (2011–2022, n = 96,658); hospitalizations (2011–2022, n = 31,407) on falls among adults aged 55 years and older at the ZIP Code level in Montana using case-crossover conditional logistic regression models. Heat was categorized based on daily temperature minimums and maximums (0°C and below, 0°+ to <32°C [reference], ≥32°C) as well as cumulative exposure (0 [reference], 1, 2, or 3+ days of ≥32°C), adjusted for daily precipitation and maximum daily humidity. Results: Daily temperatures ≥32°C were associated with increased odds of falls requiring hospitalization (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.00, 1.15), as were two consecutive days of ≥32°C (OR: 1.14, 95% CI: 1.01, 1.29). Daily temperatures ≥32°C were also associated with increased odds of EMS calls related to falls and lift assists (OR: 1.08, 95% CI: 1.02, 1.13). Conclusion: We found evidence of associations between extreme heat and fall-related hospitalizations and EMS utilization among older adults. As hospitalizations for falls significantly impact both individual health and healthcare systems, understanding and addressing heat-related fall risk is critical, especially as extreme heat events are projected to increase.