Researchers at the Brown University School of Public Health and the Columbia University School of Public Health announced on Apr. 27 that urban communities isolated by roadways and traffic patterns are associated with more schizophrenia-related hospital visits.
The study matters because it highlights how city design, specifically road infrastructure, may affect mental health beyond well-known factors like air pollution and noise. The research suggests that physical barriers created by roads can isolate communities socially, potentially leading to adverse mental health outcomes.
According to the study published in Environmental Epidemiology, ZIP code-level analyses were conducted in New York City using annual New York State Department of Health data on hospital visits related to mood, anxiety, adjustment, and schizophrenia disorders. Researchers developed a Community Severance Index to measure isolation caused by roads, traffic, and lack of pedestrian infrastructure. Marianthi-Anna Kioumourtzoglou led the development of this index while at Columbia Mailman School of Public Health.
“Imagine an environment where cars are present, but do not dominate, and that also has robust pedestrian traffic and walkable routes to neighbors’ homes, and where you can see kids playing outside and neighbors congregating to talk,” said Jaime Benavides from Brown University School of Public Health. “We wanted to home in on the road infrastructure that prevents people from interacting and learn how that influences their mental health.”
Kioumourtzoglou said: “We have increasing evidence that air pollution impacts mental health. One of the solutions proposed is to move towards an electrified vehicle fleet. While this will result in reduced emissions, which is absolutely fantastic, what our study shows is that might not be enough. We need to move away from car dependence and towards building healthier places and communities that bring people together instead of isolating them.” The researchers found higher levels of community isolation were associated with increased schizophrenia-related hospital visits across all age groups.
Benavides added: “While scientists are still researching the causes, prevention and treatment of mental illness and mood disorders, urban environmental exposures — specifically, traffic patterns and road infrastructure — are things that can be addressed from an urban planning perspective. Reducing vehicular traffic, creating more easily accessible parks and limiting highways and roads that cut through the middle of communities can improve collective mental wellbeing.” He also noted: “These findings draw attention to an overlooked urban exposure and highlight the need for further research on how features of city design may influence mental health.”
The researchers plan future work including developing a measurement for community isolation applicable nationwide as well as collaborating with Brown’s Center on Heat, Health & Aging Innovation for studies examining combined effects such as extreme heat alongside community isolation among elderly populations.
