Geographic Access to Care and Mortality in Cardiogenic Shock: A Nationwide Cohort Analysis

Abstract

IMPORTANCE: Timely access to advanced care is critical for patients with cardiogenic shock (CS), yet the impact of regional disparities in hospital arrival time on mortality remains unclear. OBJECTIVES: To investigate whether regional disparities in hospital arrival time are associated with in-hospital and long-term mortality among patients with CS. DESIGN: Population-based, nationwide cohort study. SETTING: Tertiary hospitals in South Korea, using data from the Korean National Health Insurance Service database and regional hospital accessibility indicators from the Korea Transport Institute. PARTICIPANTS: A total of 80,263 adults (≥ 18 yr) admitted to an ICU with a diagnosis of CS between 2017 and 2022. The study population was stratified by estimated hospital arrival time using region-level average daytime travel times (< 10, 10-30, 30-60, and > 60 min) for the present study. INTERVENTIONS: None. MAIN OUTCOMES AND MEASURES: The primary outcome was all-cause mortality, including in-hospital and post-discharge mortality. Multivariable logistic and Cox regression models were used to assess associations. RESULTS: Median estimated hospital arrival time was 9.15 minutes. In-hospital mortality increased progressively with longer arrival times: 29.6% (< 10 min), 33.5% (10-30 min), 34.9% (30-60 min), and 38.8% (> 60 min). Compared with less than 10 minutes, the adjusted odds ratios for in-hospital mortality were 1.27 (95% CI, 1.23-1.32), 1.24 (95% CI, 1.14-1.35), and 1.51 (95% CI, 1.29-1.75), respectively. At 1-year follow-up, the adjusted hazard ratios for all-cause mortality were 1.16 (95% CI, 1.14-1.19 for 10-30 min), 1.16 (95% CI, 1.09-1.21 for 30-60 min), and 1.31 (95% CI, 1.19-1.43 for > 60 min), relative to less than 10 minutes. These associations were consistent in both de novo and acute-on-chronic CS. CONCLUSIONS: Longer hospital arrival times are significantly associated with increased in-hospital and long-term mortality in patients with CS. These findings underscore the need for system-level interventions, such as regionally coordinated shock networks and early prehospital triage, to ensure timely access to definitive care.