Greater spatial access to care is associated with lower mortality for emergency general surgery

Abstract

Background: Emergency general surgery (EGS) diseases are time-sensitive conditions that require urgent surgical evaluation, yet the effect of geographic access to care on outcomes remains unclear. We examined the association of spatial access with outcomes for common EGS conditions.

Methods: A retrospective analysis of twelve 2014 State Inpatient Databases, identifying adults admitted with eight EGS conditions, was performed. We assessed spatial access using the spatial access ratio (SPAR)-an advanced spatial model that accounts for travel distance, hospital capacity, and population demand, normalized against the national mean. Multivariable regression models adjusting for patient and hospital factors were used to evaluate the association between SPAR with (a) in-hospital mortality and (b) major morbidity.

Results: A total of 877,928 admissions, of which 104,332 (2.4%) were in the lowest-access category (SPAR, 0) and 578,947 (66%) were in the high-access category (SPAR, ≥1), were analyzed. Low-access patients were more likely to be White, male, and treated in nonteaching hospitals. Low-access patients also had higher incidence of complex EGS disease (low access, 31% vs. high access, 12%; p < 0.001) and in-hospital mortality (4.4% vs. 2.5%, p < 0.05). When adjusted for confounding factors, including presence of advanced hospital resources, increasing spatial access was protective against in-hospital mortality (adjusted odds ratio, 0.95; 95% confidence interval, 0.94-0.97; p < 0.001). Spatial access was not significantly associated with major morbidity.

Conclusion: This is the first study to demonstrate that geospatial access to surgical care is associated with incidence of complex EGS disease and that increasing spatial access to care is independently associated with lower in-hospital mortality. These results support the consideration of spatial access in the development of regional health systems for EGS care.

Level of evidence: Prognostic and Epidemiologic; Level III.