Agent-based modeling of health resources for older adults: accessibility, equity, and last-mile solutions in Fuzhou, China

Population aging presents a critical challenge for urban sustainability and health equity. This study addresses the structural mismatch between the spatial distribution of older adults and health resources in Fuzhou, China, by developing an Agent-Based Model (ABM) to simulate the utilization of prevention, treatment, and long-term care facilities and its impact on health outcomes. The model, grounded in empirical questionnaire data and real-world spatial data, incorporates older adults as mobile agents with diverse health, economic, and living statuses, navigating a realistic urban environment over a 500-day simulation. This research designed a conceptual framework capturing the dynamic feedback between facility usage and health status. Four intervention scenarios, Multi-functional Community Centers (S1), Senior-Friendly Transportation Policies (S2), Community-based Health Education (S3), and a Comprehensive package (S4), were tested. Results indicate that spatial accessibility is the paramount driver of health improvement, with S2 (transport support) and S4 (comprehensive) demonstrating the most significant and rapid gains. Health equity, assessed via a weighted Gini coefficient, showed that while S4 achieved the most robust equity improvements across health and economic strata, its effect on residential disparities was limited. S1 risked exacerbating inequities if not precisely targeted, and S3 showed the least efficacy. The study concludes that optimizing health resources for aging populations requires a spatially-anchored, multi-dimensional strategy that prioritizes transportation accessibility, precision facility siting, and integrated service provision to effectively overcome "last-mile" barriers and address the complex needs of socioeconomically diverse older adults.