A team of researchers from the University of Edinburgh’s Alzheimer Scotland Dementia Research Centre have compiled a comprehensive shortlist of common environmental risk factors that could increase an individual’s chance of developing dementia and which may account for an approximate third of cases that have unexplained pathogenic causes.
According to the Research Centre’s report, as average life expectancy rises, the impact of dementia on global public health grows, with 47 million people worldwide currently living with the disease.
This is estimated to increase further still, with figures predicted to reach 131 million diagnoses by 2050.
Caring for those suffering from dementia costs the UK roughly £26 billion per annum, according to the report.
The new research published by the centre has found that environmental factors proposed to have a strong link to dementia risk include air pollution (nitrogen oxides, particulate matter and ozone), trace elements such as silica, occupational exposure to pesticides and solvents, and vitamin D deficiency.
Similar factors that show a moderate relation to dementia risk include carbon monoxide, tobacco smoke, the toxic heavy metal arsenic, aluminium, and electromagnetic fields.
Other factors such as lead, fluoride, paints, climate, and mobile phone usage show weak evidence of involvement in dementia.
Dr Tom Russ, one of the researchers involved in carrying out the systematic review, said in a press release: “Our ultimate goal is to prevent or delay the onset of dementia. Environmental risk factors are an important new area to consider here, particularly since we might be able to do something about them.
“We found that the evidence is particularly strong for air pollution and vitamin D deficiency. But we really need more research to find out whether these factors are actually causing dementia and how, and if so, what we can do to prevent this.”
Dr Russ spoke to The Student about the next steps in the research regarding air pollution and vitamin D deficiency.
“It is difficult to fully understand the effects of air pollution since they have not been measured too far back. For this reason, we plan to model historical levels to monitor impact, specifically those of 1936.
“We also plan to conduct a joint study of half a million people to determine the effect of varying amounts of sunlight exposure,” Russ said.
It is hoped that identifying these potential contributory factors will open doors for more focused further research that will aid the targeting of this multifactorial disease and complement efforts against well-known modifiable influences such as smoking, obesity and depression, as well as genetic factors.
This research, published in the journal BMC Geriatrics, was funded by Alzheimer Scotland and Dr Russ was supported by Alzheimer Scotland through the Marjorie MacBeath fellowship.
Image: Lucy Lambriex