Living near major roads or highways is associated with a higher risk of developing dementia, Parkinson's, Alzheimer's andMultiple sclerosis(MS). That's what new research published this week in the journal Environmental Health suggests.
Researchers at the University of British Columbia analyzed data from 678,000 adults in Metro Vancouver. They found that living less than 50 meters from a main road or less than 150 meters from a motorway is associated with a higher risk of dementia, Parkinson's, Alzheimer's and MS - likely due to increased exposure to air pollution.
The researchers also found that living near green spaces such as parks has a protective effect against the development of these neurological diseases.
“For the first time, we have confirmed an association between air pollution and transport proximity with a higher risk of dementia, Parkinson's, Alzheimer's and MS at the population level,” says Weiran Yuchi, lead author of the study and a doctoral candidate at the UBC School of Population and Public Health. “The good news is that green spaces have some protective effect by reducing the risk of developing one or more of these diseases. Further research is needed, but our results suggest that urban planning efforts to improve green space accessibility and reduce motor vehicle traffic would be beneficial for neurological health. “
For the study, researchers analyzed data from 678,000 adults between the ages of 45 and 84 who lived in Metro Vancouver from 1994 to 1998 and a follow-up period from 1999 to 2003. They estimated individual exposure to proximity to roads, air pollution, noise and green spaces where each person lives using postal code data. During the follow-up period, researchers identified 13,170 cases of non-Alzheimer's dementia, 4,201 cases of Parkinson's disease, 1,277 cases of Alzheimer's disease and 658 cases of MS.
For non-Alzheimer dementia and especially for thoseParkinson's diseaseLiving near major roads or highways was associated with a 14 percent and 7 percent increased risk of both diseases, respectively. Due to the relatively low number of Alzheimer's and MS cases in Metro Vancouver compared to non-Alzheimer's dementia and Parkinson's disease, researchers were unable to find a link between air pollution and increased risk of these two diseases. However, they are currently analyzing Canada-wide data and are confident that the larger data set will provide more information about the effects of air pollution on Alzheimer's disease and MS.
When the researchers took green spaces into account, they found that the effects of air pollution on neurological diseases were reduced. The researchers suspect that this protective effect could be due to several factors.
Professor Michael Brauer, lead author of the study, added that the results highlight the importance for urban planners to consider green spaces and parks when planning and developing neighborhoods.
