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Member Research & Reports

Member Research & Reports

Georgia State, Arizona Researchers Suggest Array of Heat Triggers for Health Warnings

Waiting until the thermometer shows a specific high temperature before issuing public health warnings is not enough to prevent a large portion of heat-related deaths and illness, according to a group of researchers including Dr. Gerardo Chowell, an associate professor of epidemiology and biostatistics at Georgia State University’s School of Public Health.

In a report titled “Multiple Trigger Points for Quantifying Heat-Health Impacts: New Evidence from a Hot Climate,” to be published in Environmental Health Perspectives, Dr. Chowell and the other researchers found that interventions should be tied to an array of heat trigger points.

For instance, the temperature threshold associated with deaths or hospitalizations resulting from dehydration were lower compared to the threshold for deaths and hospitalizations from other heat-related causes.

“[U]sing only one high threshold temperature vastly discounts the number of days on which heat is associated with higher risk of heat-related mortality or morbidity,” the researchers stated.

To reach their conclusion, the researchers from Georgia State, Arizona State University, and the University of Arizona looked at years of medical and weather data specifically from Maricopa County, Arizona, where the daily mean temperature in summer is 91.4 degrees Fahrenheit.

“In hot climates…health events associated with heat exposure may begin well before a statistical threshold temperature for all-cause mortality is crossed,” the researchers said.

Extreme heat often triggers public health responses, which may include “identifying days and times to increase enforcement of workplace safety guidelines, running seasonal public awareness campaigns, suspending utility shutoffs, rescheduling or canceling outdoor school events including athletic practices and competitions, and opening or expanding access to homeless shelters and cooling centers,” the researchers stated.

The lack of study into the link between temperature and illness and death has hampered the development of more precise public health strategies to curb heat’s adverse effects, the researchers also said.

The report also noted that identifying multiple temperature triggers will become increasingly important in the coming decades to deal with the “potential future health effects of local, regional, or global scale climate change.”

The other authors were Dr. Diana B. Petitti of the University of Arizona, and Dr. David M. Hondula, Shuo Yang and Dr. Sharon L. Harlan, from Arizona State University.