Experienced economic segregation and associated mental health inequalities across urbanicity.

The global mental health burden is rising, with economic segregation as a key social determinant contributing to mental health and its inequalities. However, most studies rely on residential-based segregation measures failing to capture the actual segregation individuals experience through daily mobility and activities. Using a large-scale mobility dataset across the contiguous United States, we quantify mobility-based economic segregation and examine its associations with mental health outcomes across income groups and urbanicity levels. We find that individuals in the lowest and highest income quartiles exhibit strong self-segregation. A 0.1-unit increase in economic segregation is observed to be associated with a 0.64 % (95 % CI: 0.60 %-0.68 %) rise in poor mental health prevalence among lowest income quartile groups and a 0.29 % (95 % CI: 0.26 %-0.32 %) decline among highest income quartile groups in metropolitan areas. In less urbanized areas, the adverse mental health impacts of mobility-based economic segregation remain significant for low-income groups, while no significant health impact is observed for high-income groups. These findings suggest that mobility-based economic segregation may intensify economic disparities in mental health outcomes. Interventions that enhance upward social mixing for low-income individuals through changes in their mobility may help reduce adverse impacts of economic segregation on mental health and mitigate associated inequalities.