Who Is at Risk of Death in an Earthquake?

TLDR

Disaster impacts are not randomly distributed across health and socioeconomic classes, but empirical evidence is scarce. In a population‑based cohort of 297,047 victims of the 1999 Taiwan earthquake, the authors identified mortality risk factors by adjusting odds ratios for individual and neighborhood variables. Mental disorders, moderate physical disabilities, recent hospitalization, and lower monthly wages were associated with higher odds of death, indicating that earthquake mortality is not random and highlighting vulnerable groups.

Abstract

Although, theoretically, the impacts of a disaster are not randomly distributed across health and socioeconomic classes, empirical evidence of this claim is scarce. In a population-based cohort study, the authors identified risk factors for mortality from the September 21, 1999, Taiwan earthquake, which occurred in the middle of the night. Among 297,047 earthquake victims in central Taiwan who experienced partial or complete dwelling damage, 295,437 (noncases) survived the earthquake and 1,610 (cases) died between September 21 and October 31, 1999. Odds ratios were adjusted for both micro-level individual variables and macro-level neighborhood variables. People with mental disorders (odds ratio (OR) = 2.0, 95% confidence interval (CI): 1.1, 3.5), people with moderate physical disabilities (OR = 1.7, 95% CI: 1.2, 2.3), and people who had been hospitalized just prior to the earthquake (OR = 1.4, 95% CI: 1.2, 1.7) were the most vulnerable. The degree of vulnerability increased with decreasing monthly wage (measured in New Taiwanese dollars (NT$)) (NT$20,000∼NT$39,999: OR = 1.5, 95% CI: 1.1, 2.1; <NT$20,000: OR = 2.2, 95% CI: 1.6, 3.0). The significant associations of both prequake health status and socioeconomic status with earthquake death suggest that earthquake death did not occur randomly. These results might help to guide allocation of public resources for reducing casualties.