title: Warm season temperatures and emergency department visits in Atlanta, Georgia.
abstract: OBJECTIVE
  Extreme heat events will likely increase in frequency with climate change. Heat-related health effects are better documented among the elderly than among younger age groups. We assessed associations between warm-season ambient temperature and emergency department (ED) visits across ages in Atlanta during 1993-2012.
  
  
  METHODS
  We examined daily counts of ED visits with primary diagnoses of heat illness, fluid/electrolyte imbalances, renal disease, cardiorespiratory diseases, and intestinal infections by age group (0-4, 5-18, 19-64, 65+years) in relation to daily maximum temperature (TMX) using Poisson time series models that included cubic terms for TMX at single-day lags of 0-6 days, controlling for maximum dew-point temperature, time trends, week day, holidays, and hospital participation periods. We estimated rate ratios (RRs) and 95% confidence intervals (CI) for TMX changes from 27°C to 32°C (25th to 75th percentile) and conducted extensive sensitivity analyses.
  
  
  RESULTS
  We observed associations between TMX and ED visits for all internal causes, heat illness, fluid/electrolyte imbalances, renal diseases, asthma/wheeze, diabetes, and intestinal infections. Age groups with the strongest observed associations were 65+years for all internal causes [lag 0 RR (CI)=1.022 (1.016-1.028)] and diabetes [lag 0 RR=1.050 (1.008-1.095)]; 19-64 years for fluid/electrolyte imbalances [lag 0 RR=1.170 (1.136-1.205)] and renal disease [lag 1 RR=1.082 (1.065-1.099)]; and 5-18 years for asthma/wheeze [lag 2 RR=1.059 (1.030-1.088)] and intestinal infections [lag 1 RR=1.120 (1.041-1.205)].
  
  
  CONCLUSIONS
  Varying strengths of associations between TMX and ED visits by age suggest that optimal interventions and health-impact projections would account for varying heat health impacts across ages.
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322, USA. Electronic address: awinqui@emory.edu.
authors.forename: Andrea
authors.initials: A
authors.lastname: Winquist
authors.affiliation: Department of Geography, University of Georgia, 210 Field Street, Atlanta, GA 30322, USA. Electronic address: andrewg@uga.edu.
authors.forename: Andrew
authors.initials: A
authors.lastname: Grundstein
authors.affiliation: Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322, USA. Electronic address: howard.chang@emory.edu.
authors.forename: Howard H
authors.initials: HH
authors.lastname: Chang
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322, USA. Electronic address: jjhess@uw.edu.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Hess
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322, USA. Electronic address: sebelt@emory.edu.
authors.forename: Stefanie Ebelt
authors.initials: SE
authors.lastname: Sarnat
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002947:Cities; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D055874:Extreme Heat / Q000009:adverse effects*; D005845:Georgia; D018882:Heat Stress Disorders / Q000150:complications / Q000453:epidemiology* / Q000628:therapy; D006801:Humans; D007223:Infant; D008875:Middle Aged; D015233:Models, Statistical; D012621:Seasons; D055815:Young Adult
keywords: Climate change; Emergency department visits; Heat; Temperature; Time series