title: Impact of the 2011 heat wave on mortality and emergency department visits in Houston, Texas.
abstract: BACKGROUND
  Heat waves have been linked to increased risk of mortality and morbidity, and are projected to increase in frequency and intensity in a changing climate. Houston and other areas in Texas experienced an exceptional heat wave in the summer of 2011 producing the hottest August on record. This study aims to assess the health-related impact of this heat wave.
  
  
  METHODS
  Distributed lag models were used to estimate associations between the 2011 heat wave and all-cause mortality and emergency department (ED) visits from May 1 through September 30 for the five-year period 2007-2011. The 2011 heat wave is defined as a continuous period from August 2 through 30, 2011 according to the heat advisories issued by the local National Weather Service office, and is included in the models as a dummy variable. We compared the estimated excess risk among the models with and without adjustment of continuous temperature and ozone.
  
  
  RESULTS
  The 2011 heat wave in Houston was associated with a 3.6% excess risk in ED visits (95% CI: 0.6%, 6.6%) and 0.6% increase in mortality risk (95% CI: -5.5%, 7.1%). The elderly over 65 years of age were at the greatest risk in ED visits. These patterns are consistent across different heat-wave definitions, and results are similar when adjusting for continuous temperature and ozone.
  
  
  CONCLUSIONS
  The 2011 heat wave in Houston had a substantial impact on ED visits and no significant impact on mortality. Our findings provide insights into local heat-wave and health preparations and interventions.
authors: Department of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health, Houston, Texas, 77030, USA. kai.zhang@uth.tmc.edu.
authors: Kai
authors: K
authors: Zhang
authors: Department of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health, Houston, Texas, 77030, USA.
authors: Tsun-Hsuan
authors: TH
authors: Chen
authors: Department of Management, Policy and Community Health, University of Texas School of Public Health, Houston, Texas, USA.
authors: Charles E
authors: CE
authors: Begley
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death / Q000639:trends*; D002648:Child; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D005544:Forecasting; D018883:Heat Stroke / Q000453:epidemiology / Q000401:mortality*; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010126:Ozone / Q000009:adverse effects*; D012307:Risk Factors; D013781:Texas / Q000453:epidemiology; D014887:Weather; D055815:Young Adult
chemical_list: D010126:Ozone
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