Regional disparities in 1-month survival following traffic accident-related out-of-hospital cardiac arrest in Japan: A nationwide observational study

Am J Emerg Med. 2025 Oct:96:249-255. doi: 10.1016/j.ajem.2025.07.002. Epub 2025 Jul 3.

Abstract

Aim: To clarify regional disparities in 1-month survival after traffic accident-related out-of-hospital cardiac arrest (OHCA) in Japan and examine associations with emergency medical services (EMS) and healthcare indicators.

Methods: We conducted a retrospective study of 9525 traffic accident-related OHCAs using national EMS data from 2018 to 2022. Prefectures were grouped by 1-month survival rates. Multivariable logistic regression and partial correlation analyses assessed factors related to patient characteristics, EMS, and medical resources.

Results: In low-survival regions, rates of advanced airway management (37.7 %) and epinephrine administration (29.8 %) were significantly higher (p < 0.001). Conversely, the proportion of patients transported to level-3 hospitals was significantly higher in high-survival regions (p < 0.001). Logistic regression revealed that advanced airway management (OR: 1.37; 95 % CI: 1.22-1.54; p < 0.001), epinephrine administration (OR: 1.43; 95 % CI: 1.26-1.62; p < 0.001), and traffic accidents as the direct cause of cardiac arrest (OR: 1.17; 95 % CI: 1.04-1.30; p = 0.006) were significantly associated with lower-survival regions. In contrast, witnessed arrests (OR: 0.82; 95 % CI: 0.73-0.92; p = 0.001), BCPR (OR: 0.85; 95 % CI: 0.75-0.96; p = 0.012), and transport to level-3 hospitals (OR: 0.71; 95 % CI: 0.64-0.80; p < 0.001) were negatively associated with classification into low-survival regions. Partial correlation analysis showed positive associations between survival and the number of level-3 hospitals (r = 0.45) and physicians (r = 0.36, p = 0.08) per 100,000 population.

Conclusion: Survival outcomes following traffic accident-related cardiac arrest varied across regions, and distribution of medical resources appeared to influence these disparities.

Keywords: Emergency medical services; Out-of-hospital cardiac arrest; Outcome; Regional disparity; Traffic accident.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Accidents, Traffic* / mortality
  • Accidents, Traffic* / statistics & numerical data
  • Adult
  • Aged
  • Airway Management / statistics & numerical data
  • Cardiopulmonary Resuscitation / statistics & numerical data
  • Emergency Medical Services* / statistics & numerical data
  • Epinephrine / therapeutic use
  • Female
  • Healthcare Disparities* / statistics & numerical data
  • Humans
  • Japan / epidemiology
  • Male
  • Middle Aged
  • Out-of-Hospital Cardiac Arrest* / etiology
  • Out-of-Hospital Cardiac Arrest* / mortality
  • Out-of-Hospital Cardiac Arrest* / therapy
  • Retrospective Studies
  • Survival Rate

Substances

  • Epinephrine