What states are most at risk? An epidemiologic analysis of state-level occupational heat-related illness and fatality trends over three decades.

BACKGROUND: Occupational heat-related illnesses and fatalities are a growing public health concern. Understanding longitudinal geographic patterns and predictors can inform targeted prevention efforts. METHODS: This study assessed three decades of state-level U.S. Bureau of Labor Statistics (BLS) data on occupational heat-related illnesses (1992-2020) and fatalities (1992-2022). Generalized linear models (Poisson, negative binomial, and gamma regression) as well as linear regression models assessed temporal and temperature-related associations. RESULTS: Substantial geographic variation was observed. Sixteen states showed increasing trends in heat-related illnesses, with several also experiencing rising median days lost from work, indicating increasing severity. Temperature averages were significantly associated with illness frequency and proportional rates across multiple states. Fatalities demonstrated less consistent associations, though most notably Texas exhibited a significant increase in worker deaths over time, with additional temperature-related trends in Texas and Arizona. CONCLUSION: Heat-related occupational illness and severity are rising in multiple U.S. states, highlighting the need for state-specific prevention and adaptation strategies. Findings support the development of workforce resilience standards and targeted interventions in high-risk industries during extreme heat events. This work contributes to the evidence base for policy development and workplace interventions to reduce heat-related occupational morbidity and mortality.