Authors: Sharon Salt, Editor
Tom Russ is a Consultant Psychiatrist in NHS Lothian in Edinburgh (UK). He is also the Co-Director of the Alzheimer Scotland Dementia Research Center at the University of Edinburgh.
In this interview, Tom speaks to us about life course air pollution exposure and cognitive decline in Scotland (UK) from the Lothian Birth Cohort of 1936. He also discusses the significance of the relationship between air pollution and neurological disorders, and what his opinion on this is.
What are your current research focuses and what inspired you to work in this area?
A few years ago, we started to examine geographical variation in dementia risk, initially looking at Scotland and Sweden. In Sweden, they have a register of all the twins who have been born since the middle of the 19th century and approximately 10 years ago, researchers from the Karolinska Institute (Stockholm, Sweden) and the University of Southern California (CA, USA) contacted every one of these twins who was over the age of 65 and established who had dementia. We then used these data to investigate the geographical spread of dementia in Sweden, and because they were twins, we could take out the genetic effects.
Even with the genetic effects removed there was still a big variation. For example, there was a two- to three-fold higher risk in the north compared to the south. As we knew this wasn’t due to genetics, it was more likely to be an environmental risk. This led us to investigate a wide array of environmental risk factors, with a particular focus on air pollution.
You’ve presented a talk here at the Alzheimer’s Association International Conference (AAIC; 22–26 July, IL, USA) on ‘Life course air pollution exposure and cognitive decline in Scotland’ – could you provide an overview about this?
There have been a large number of studies linking air pollution with dementia. However, the risk for developing dementia potentially starts right early in life. This means that influences at all stages of life could increase or decrease your risk.
What we don’t know is when the exposure to air pollution is particularly bad, or if it is just a cumulative effect of the entirety of your life. The main thing that stops us from looking at this is the fact that we have only really been monitoring air pollution over the last 20 or 30 years. This is because that timeframe is when the government and the EU, for example, specified that we should do this and that’s when the monitoring started.