Fuyuen Y. Yip, W. Dana Flanders, Amy Wolkin, David Engelthaler, William Humble, Antonio Neri, Lauren Lewis, Lorraine Backer, Carol Rubin

International Journal of Biometeorology

Published date July 8, 2008

The impact of excess heat events in Maricopa County, Arizona: 2000–2005

  • States that exposure to excess heat is preventable yet it is the primary weather-related cause of mortality in the United States
  • States that in the Southwest United States, high temperatures are common and indoor environments often have cooling devices
  • States that in summer 2005, Maricopa County, Arizona experienced a 182% increase in reported heat-related deaths in comparison to 2000–2004
  • Examines at-risk populations and excess mortality
  • Characterizes heat-related deaths using descriptive and multivariate time-series analyses of county vital record data from June–September 2000–2005
  • Describes the data: From June–September, 2000–2005, 136 heat-related deaths (0.68 per 100,000) were reported; 49 (36%) occurred in 2005. In July 2005, a 14-day heat wave resulted in 28 (57%) reported deaths—a 102% increase in comparison to the same time period in 2000–2004. The mean age of all 136 deaths was 56 years (range: 7–92 years). Of those with discernable reported injury locations, 62 (66%) were identified outdoors. Forty-eight (77%) decedents identified outdoors were <65 years; conversely, 26 (82%) decedents who were found indoors were ≥65 years
  • Observes a 6% (95% CI: 1.00–1.13) increase in mortality risk for each degree (F) increase in heat index
  • Finds that excess heat impacted a younger population in Maricopa County and many deaths occurred outdoors
  • Concludes that consecutive days of heat exposure—even among a heat-acclimated population—can increase mortality risk