New Evidence from a Hot Climate: Considering Multiple Health Events, Exposure Variables, and Trigger Points for Interventions Related to Health Impacts of High Temperatures
We found statistically significant and consistently strong associations of high environmental temperature with all-cause mortality, heat-related mortality, heat-related hospitalization and heat-related ED visits. The temperature at which heat-related morbidity events began to increase was 3-6 degrees (C) lower than that at which heat-related mortality began to increase in this setting. Large contrasts were found for the environmental conditions at which heat-health interventions might be activated based on different conceptualizations of trigger points. Choice of exposure variable significantly altered model performance for some but not all health events.
Consideration of a broader set of health events together with a comprehensive approach to identify threshold temperatures and optimal exposure variables for effects of heat on health revealed a need to identify additional strategies to mitigate the effects of high environmental heat on human health. The health burden associated with high temperatures is expected to become more important based on projections of warming and increasing vulnerability.