Living in “20-Minute Neighborhoods“ Good for Your Brain
Article Summary
- Researchers at the University of Miami Miller School of Medicine have shown that 20-minute neighborhoods can have a positive impact on brain health.
- The study looked at 352 older adults to determine whether neighborhood walkability impacted their brain health.
- The researchers found major reductions in white matter hyperintensity, a risk factor associated with dementia.
Researchers at the Comprehensive Center for Brain Health at the University of Miami Miller School of Medicine have shown that 20-minute neighborhoods can have a positive impact on brain health. Living in a walkable neighborhood with easy access to groceries, medical care, public transit and other basic needs was associated with reduced white matter hyperintensity (WMH), which has been linked to increased stroke and dementia risk.
The study was published in the journal Health and Place.
“Urban planners are always thinking about the elements that go into stronger communities,” said Lilah Besser, Ph.D., M.S.P.H, research associate professor in the Miller School’s Department of Neurology and first author on the study. “We have an aging population, and we’re going to have to adapt our living environments to that reality. This provides a more direct measure of brain health and shows how evidence-based planning could potentially reduce dementia risk.”
Brain Health Meets Urban Planning
Dr. Besser’s paper is part of the Healthy Brain Initiative (HBI), which investigates personalized approaches that could help people preserve their cognitive health. HBI participants are 50 or older and have no cognitive impairment, slight impairment or mild dementia.
“With this approach, instead of reacting to disease, we can begin to think about preventing disease,” said James Galvin, M.D., M.P.H., professor of neurology at the Miller School, chief of the Division of Cognitive Neurology, founding Comprehensive Center for Brain Health director, director of the Lewy Body Dementia Research Center of Excellence, principal investigator on the HBI and senior author on the current study. “We can predict susceptibility and improve early detection. We might be able to halt or slow disease progression.”
The study looked at 352 older adults from the HBI cohort to determine whether neighborhood walkability impacted their brain health. A 20-minute neighborhood was defined as having shopping, dining, groceries, health care, parks, social destinations and public transit within that walkable range. Previous studies had looked at some of these factors but never all at once.
The study focused on three factors:
• White matter hyperintensity
• Hippocampal volume, a marker for Alzheimer’s disease
• Resilience index scores, which measure a person’s risk of developing dementia
While the researchers found major reductions in white matter hyperintensity, there were no significant increases in hippocampal volume, though early data hinted there might be. The team also did not find any major improvements in the resilience index scores, which could be attributable to study design.
The Benefits of the 20-Minute Neighborhood
Still, the white matter hyperintensity improvements alone indicate 20-minute neighborhoods can have a beneficial impact on the brain. There are a variety of possible mechanisms that could explain these improvements. Exercise has long been linked to greater cognitive health, as has green space. In addition, being able to move freely around a neighborhood provides more opportunity for social interaction, which can also protect against dementia.
“We’re thinking about how we can build communities to help reduce social isolation,” said Dr. Besser. “If people have more places to walk nearby, they’re more likely to interact with their neighbors.”
This study is one piece of the Comprehensive Center for Brain Health’s long-term efforts to identify the factors that can protect people from cognitive decline. The authors anticipate more research to better understand how 20-minute neighborhoods support better brain health.
“We would definitely like to expand to a national cohort,” said Dr. Besser. “South Florida has unique attributes, but it’s also quite driving focused. We’d like to see whether these results could be generalized nationally.”
Tags: Alzheimer's disease, cognitive decline, Comprehensive Center for Brain Health, dementia, Department of Neurology, Dr. James Galvin, Dr. Lilah M. Besser, greenness, neurology, Newsroom, stroke