Association Between Rurality and Mortality: Observational Study of Spanish and United States Prehospital Emergency...

Background/Objectives: Differences between rural and urban settings, as well as between emergency medical service (EMS) systems, may influence short-term mortality among patients attended in the prehospital setting. The aim of this study was to determine the associations of rurality and the US and Spanish EMS health systems with patient mortality. Methods: This was a multicenter, EMS-based, observational study involving a prospective dataset, the Salud de Castilla y Leon dataset (SACYL) from Spain, and a retrospective dataset, the National Emergency Medical Services Information System (NEMSIS) from the US. All consecutive EMS activations of adult patients (≥18 years) requiring high-priority transport to emergency departments were included in the analysis. The collected variables included demographic characteristics, EMS transport characteristics, case characteristics, and rural or urban origin. The primary outcome was 2-day, short-term mortality. Results: A total of 54,981 EMS activations were considered from both datasets. The mortality rate was 8.47% for rural areas and 11.8% for urban areas (p < 0.001). Multivariable analyses showed that mortality patterns differed according to geographic setting and EMS system. Male sex and the use of advanced life support were associated with higher odds of mortality in several models, while prehospital time intervals and call characteristics showed context- and system-dependent associations, including protective effects in specific subgroups. Conclusions: Short-term mortality differed between rural and urban settings, with heterogeneous patterns across EMS systems. These findings highlight the importance of considering both geographic context and system-level organizational characteristics when evaluating prehospital care and mortality outcomes.