Living Close to Heavy Traffic Increases Dementia Risk


According to new scientific research, those living near busy main roads are more likely to suffer with dementia.

The study estimates that 1 in 10 Alzheimer cases in urban areas could be associated with heavy traffic.  The study did not cite exhaust fumes as a cause of neurodegeneration.

Hong Chen, from Public Health Ontario said, “Increasing population growth and urbanisation has placed many people close to heavy traffic, and with widespread exposure to traffic and growing rates of dementia, even a modest effect from near-road exposure could pose a large public health burden.”

Earlier studies linked air pollution and traffic noise to reducing the density of white matter in the brain and lower cognition.  It is believed that magnetic nano-particles in air pollution may be able to penetrate brain tissue.

The study published in the Lancet, concluded that those that live near heavy traffic routes were 12% more likely to suffer with dementia.  The study monitored 6.6 million people over ten years.  Although traffic seems to be a factor, other factors such as lifestyles and respiratory and cardiac issues could also have an effect on being more at risk of dementia.

Rob Howard, professor of old age psychiatry at University College London was not involved in the study but said, “We know that major road air pollution is bad for general health and this latest study doesn’t tell us whether the small increase in dementia risk is driven by indirect effects or whether proximity to traffic directly influences dementia pathology. Regardless of the route of causation, this study presents one more important reason why we must clean up the air in our cities.”

The study was carried out in Ontario from 2001 to 2012, monitoring adults between 20 and 85.  It used postcodes to determine how close a person lived to a heavy traffic area.

The ramifications of the study are likely to be felt at a political level.