Identifying heat-related deaths by using medical examiner and vital statistics data: Surveillance analysis and descriptive epidemiology - Oklahoma, 1990-2011

Environ Res. 2016 Oct:150:30-37. doi: 10.1016/j.envres.2016.05.035. Epub 2016 May 26.

Abstract

Objectives: Approximately 660 deaths occur annually in the United States associated with excess natural heat. A record heat wave in Oklahoma during 2011 generated increased interest concerning heat-related mortality among public health preparedness partners. We aimed to improve surveillance for heat-related mortality and better characterize heat-related deaths in Oklahoma during 1990-2011, and to enhance public health messaging during future heat emergencies.

Methods: Heat-related deaths were identified by querying vital statistics (VS) and medical examiner (ME) data during 1990-2011. Case inclusion criteria were developed by using heat-related International Classification of Diseases codes, cause-of-death nomenclature, and ME investigation narrative. We calculated sensitivity and predictive value positive (PVP) for heat-related mortality surveillance by using VS and ME data and performed a descriptive analysis.

Results: During the study period, 364 confirmed and probable heat-related deaths were identified when utilizing both data sets. ME reports had 87% sensitivity and 74% PVP; VS reports had 80% sensitivity and 52% PVP. Compared to Oklahoma's general population, decedents were disproportionately male (67% vs. 49%), aged ≥65 years (46% vs. 14%), and unmarried (78% vs. 47%). Higher rates of heat-related mortality were observed among Blacks. Of 95 decedents with available information, 91 (96%) did not use air conditioning.

Conclusions: Linking ME and VS data sources together and using narrative description for case classification allows for improved case ascertainment and surveillance data quality. Males, Blacks, persons aged ≥65 years, unmarried persons, and those without air conditioning carry a disproportionate burden of the heat-related deaths in Oklahoma.

Keywords: Heat; Medical examiner; Mortality; Oklahoma; Vital statistics.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Cause of Death*
  • Child
  • Child, Preschool
  • Female
  • Hot Temperature / adverse effects*
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Middle Aged
  • Oklahoma / epidemiology
  • Population Surveillance*
  • Young Adult