Long-Term Mortality in Patients Transferred by Emergency Medical Services: Prospective Cohort Study

Objective: This study aimed to determine the long-term mortality (one-year follow-up) associated with patients transferred by Emergency Medical Services (EMS), and to reveal the determinants (causes and risk factors). Methods: This was a multicenter, prospective, observational, controlled, ambulance-based study of adult patients transferred by ambulance to emergency departments (EDs) from October 2019 through July 2021 for any cause. A total of six Advanced Life Support (ALS) units, 38 Basic Life Support (BLS) units, and five hospitals from Spain were included. Physiological, biochemical, demographic, and reasons for transfer variables were collected. A longitudinal analysis was performed to determine the factors associated to long-term mortality (any cause). Results: The final cohort included 1,406 patients. The one-year mortality rate was 21.6% (n = 304). Mortality over the first two days reached 5.2% of all the patients; between Day 2 and Day 30, reached 5.3%; and between Day 31 and Day 365, reached 11.1%. Low Glasgow values, elevated lactate levels, elevated blood urea nitrogen (BUN) levels, low oxygen saturation, high respiratory rate, as well as being old and suffering from circulatory diseases and neurological diseases were risk factors for long-term mortality. Conclusion: The quick identification of patients at risk of long-term worsening could provide an opportunity to customize care through specific follow-up.