Population aging and the spatial equity of prehospital emergency medical resources: evidence from Shanghai's five new towns

BackgroundChina is undergoing rapid urbanization and profound population aging, presenting the prehospital emergency medical system with the dual challenges of inadequate capacity and spatial mismatch. Shanghai's five new towns are strategic vehicles for the spatial restructuring of a megacity; however, evidence is still lacking as to whether their prehospital emergency systems can meet the aging-driven increase in demand.ObjectiveTo evaluate the spatial equity of emergency medical resource allocation in the five new towns and to analyze its associations with population aging and future demand.MethodsBased on 2024 data, the Gini coefficient and Theil index were used to evaluate equity; population projections were performed using the cohort-component method in PADIS-INT (population analysis software); resource requirements were estimated in stages according to policy standards; and coverage gaps were identified through isochrone analysis in QGIS (open-source geographic information system).ResultsThe population-based Gini coefficients across the five districts ranged from 0.03 (substations) to 0.10 (physicians), indicating relatively equitable per capita allocation. However, after including all 16 districts of the municipality, the area-based Gini coefficient for substations reached 0.61, reflecting a gradient in substation density between the urban core and the suburbs. Under the medium scenario, the population aged 65 years and older in Jiading increases from 13.18% to 19.15% (2035), and the demand for R1 standard ambulances in Jiading New City is projected to rise from 24 vehicles in 2025 to 29 vehicles in 2035. In Fengxian, patients aged 60 years and above accounted for 48.49% of emergency calls. Highly aged subdistricts spatially overlapped with 8 min coverage blind spots. Notably, stratified emergency response time (ERT) analysis showed that in two of the three districts, the differences in ERT between cardiac arrest and non-emergency patients were not statistically significant (p > 0.05), suggesting limited implementation of dispatch prioritization.ConclusionThe five new towns exhibit a dual-track pattern of equity in population terms but inequity in spatial terms. Population aging exacerbates inequity through demand expansion, changes in the disease spectrum, and spatial overlap.