Independent scientists respond to a study that highlights a possible link between heavy traffic and dementia
Results of dementia research revealed
Dementia is more likely to strike people that live close to major roads which suggests air pollution and/or noise from traffic might be contributing factors, The Lancet suggested. The Canadian medial journal based its conclusion on a study of close to 2 million people which resided in the province of Ontario, from 2001 to 2012.
During this time frame, 243,611 residents were diagnosed with the degenerative brain condition in the studied regions. Scientists concluded that compared to living 300 metres from a major thoroughfare the risk was: 7% higher within 50 metres, 4% higher between 50 and 100 metres and 2% higher between 101 and 200 metres.
The Lancet suggested that 7 to 11% of cases within 50 metres of a major road might have been caused by traffic, the BBC summarised. It added that scientists adjusted data to account for other risk factors such as poverty, obesity, levels of education, and smoking.
Report author summarises research
Dr Hong Chen, from Public Health Ontario and one of the report authors, argued: "Increasing population growth and urbanisation have placed many people close to heavy traffic. 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.”
Chen added: "More research to understand this link is needed, particularly into the effects of different aspects of traffic, such as air pollutants and noise."
Independent scientists respond to research
The wider scientific world responded with interest to the report's suggestions. Dr David Reynolds, Chief Scientific Officer at Alzheimer's Research UK, concluded: "Conditions like dementia have multiple risk factors including age, genetics, and other social factors. Where people live in cities could also be playing a part.”
"This study has identified major roads and air pollutants from traffic as possible risk factors for dementia, a finding which will need further investigation before any firm conclusions can be drawn about the relative risks of air pollutants for dementia versus other risks such as smoking, lack of exercise or being overweight."
Professor Tom Dening, Director of the Centre for Dementia for the University of Nottingham, added: "It is certainly plausible that air pollution from motor exhaust fumes may contribute to brain pathology that over time may increase the risk of dementia.”
“This evidence will add to the unease of people who live in areas of high traffic concentration. Undoubtedly living in conditions of severe air pollution is extremely unpleasant and it is hard to suppose that it is good for anyone", Professor Dening concluded.