Last updated April 4, 2019

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