title: Vulnerability to extreme-heat-associated hospitalization in three counties in Michigan, USA, 2000-2009.
abstract: With climate change, extreme heat (EH) events are increasing, so it is important to understand who is vulnerable to heat-associated morbidity. We determined the association between EH and hospitalizations for all natural causes; cardiovascular, respiratory, and renal diseases; diabetes mellitus; and acute myocardial infarction in Michigan, USA, at different intensities and durations. We assessed confounding by ozone and how individual characteristics and health insurance payer (a proxy for income) modified these associations. We obtained Michigan Inpatient Database, National Climatic Data Center, and US Environmental Protection Agency ozone data for May-September, 2000-2009 for three Michigan counties. We employed a case-crossover design and modeled EH as an indicator for temperature above the 95th, 97th, or 99th percentile thresholds for 1, 2, 3, or 4 days. We examined effect modification by patient age, race, sex, and health insurance payer and pooled the county results. Among non-whites, the pooled odds ratio for hospitalization on EH (97th percentile threshold) vs. non-EH days for renal diseases was 1.37 (95 % CI = 1.13-1.66), which increased with increasing EH intensity, but was null among whites (OR = 1.00, 95 % CI = 0.81, 1.25). We observed a null association between EH and cardiovascular hospitalization. EH (99th percentile threshold) was associated with myocardial infarction hospitalizations. Confounding by ozone was minimal. EH was associated with hospitalizations for renal disease among non-whites. This information on vulnerability to heat-associated morbidity helps characterize the public health burden of EH and target interventions including patient education.
authors: Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI, 48109, USA.
authors: Adesuwa S
authors: AS
authors: Ogbomo
authors: Department of Epidemiology, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI, 48109,, USA. gronlund@umich.edu.
authors: Carina J
authors: CJ
authors: Gronlund
authors: Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI, 48109, USA.|Department of Epidemiology, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI, 48109,, USA.
authors: Marie S
authors: MS
authors: O'Neill
authors: Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI, 48109, USA.
authors: Tess
authors: T
authors: Konen
authors: Division of Environmental Health, Michigan Department of Health and Human Services, 333 South Grand Ave, Lansing, MI, 48913, USA.
authors: Lorraine
authors: L
authors: Cameron
authors: Lifecourse Epidemiology and Genomics Division, Michigan Department of Health and Human Services, 333 South Grand Ave, Lansing, MI, 48913, USA.
authors: Robert
authors: R
authors: Wahl
mesh_terms: D000368:Aged; D000393:Air Pollutants / Q000032:analysis; D002318:Cardiovascular Diseases / Q000453:epidemiology; D003920:Diabetes Mellitus / Q000453:epidemiology; D055874:Extreme Heat / Q000009:adverse effects*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology; D008297:Male; D008824:Michigan / Q000453:epidemiology; D010126:Ozone / Q000032:analysis; D012140:Respiratory Tract Diseases / Q000453:epidemiology
chemical_list: D000393:Air Pollutants; D010126:Ozone
keywords: Heat; Heat wave; Hospitalization; Morbidity; Temperature