Joint modelling of air pollution exposure and risk of dementia

The challenge

Dementia is a leading cause of death, disability, and dependency among older people across the world, while air pollution levels far exceed guidelines set by the World Health Organisation. 

There is increasing evidence of the toxic effects of various air pollutants on the brain, particularly for particulate matters (PMs) and nitric oxides (NOx). Due to their ubiquitous presence in our environment, it remains difficult to detect if these pollutants are major risk factors for dementia.

There is still considerable uncertainty on the magnitude of this risk, especially at a population level, which hinders translation of scientific results into public health policies, urban planning, and public awareness. 

What we're doing

One of the main sources of uncertainty comes from quantifying exposure to air pollution. In particular, exposure to air pollution occurs over long periods of time, during which relatively small neuronal damage accrues and gradually increases the risk of developing dementia.

Nevertheless, most studies have considered the impact of exposure measured at a single time point on future risk of dementia, thus introducing bias and variability in the results.

To overcome this problem, we will model longitudinal exposure to pollutants using measurements at multiple time points and link this exposure to risk of dementia using data from the UK Biobank cohort. This approach will allow us to appropriately estimate the cumulative neurodegenerative effects of air pollution. 

How it helps

Overall, our project will significantly improve on current work and support policies that aim to reduce the risk of dementia and promote a healthier environment. 

Investigators

• Dr Ana Goncalves Soares, Bristol Medical School 
• Dr Ensor Rafael Palacios, University of Bath 
• Prof Kate Tilling, Bristol Medical School 
• Dr Gareth Griffith, Bristol Medical School 
• Dr Maryam Makanvand, Bristol Medical School 
• Dr Theresa Smith, University of Bath 
• Dr Eunice Lo, School of Geographical Sciences 
• Prof Patrick Kehoe, Bristol Medical School