Traffic And Dementia
Living within 55 yards of a major road could elevate the risk of dementia, according to a new Canadian study. Ontario researchers reported a seven percent increased risk among people living closest to busy roads compared to those who lived more than 328 yards away. The additional risk dropped from seven percent to two percent and then to zero as distance lived from highways increased. The investigators reviewed the health records of more than 6.6 million Ontario residents aged 20 to 85 to explore the connection – if any – between living close to busy highways and the risk of dementia, Parkinson’s disease and multiple sclerosis. They observed no additional risk due to living location and Parkinson’s disease or multiple sclerosis, and postulated that air quality might be a factor in the risk for dementia. (While the investigation showed an association between air pollution and dementia, it did not prove cause and effect). However, Ray Copes, M.D. a study author and chief of environmental and occupational health at Public Health Ontario said the study suggests that air pollutants can get into the brain via the blood stream and lead to neurological problems.
My take? This report adds intriguing information to previous findings about the negative effects of air pollution on health. We’ve known for some time that pollution can worsen respiratory problems. Its link to a greater risk of stroke (and heart attack) has been recognized for more than a decade. And a study published in 2012 associated living in areas with the worst air quality to poor performance on memory and thinking tests among women in their 70s. The positive underlying message of this research is that our living environment is a modifiable risk, and should be considered carefully.
Hong Chen et al, “Living near major roads and the incidence of dementia, Parkinson’s disease, and multiple sclerosis: a population-based cohort study.” The Lancet, January 4, 2017, DOI: http://dx.doi.org/10.1016/S0140-6736(16)32399-6
Jennifer Weuve et al, “Exposure to Particulate Air Pollution and Cognitive Decline in Older Women.” Archives of Internal Medicine, February 13, 2012, doi:10.1001/archinternmed.2011.683
Also in this week’s bulletin: