The impact of the Environment and Pollution On Cognitive Health
Lively, high compact, that are rich in leisure and business destinations, provide older populations with opportunities to take part in physical, social, and mental activities that improve their cognitive health- that is their ability to think, learn, reason, and remember. However, these type of environments are also linked to harmful amounts of traffic pollution and noise. Studies integrating the effect of the built environments (manmade structures, features, and facilities that provide the setting for where people live and work, e.g., parks, local services) and the side effects produced by these these environments (pollution, noise etc.), are limited. Most often focus on either how the built environment promotes physical activity, or the effect of air pollution in single locations. To properly understand how neighborhood factors can affect cognitive health it is important to study all positive and negative influences of the environment across a wide range of locations. EPOCH will combine data on the neighborhood built environment, the natural environment (natural water features, distance to parks, greenness) and pollution (air pollution and noise) from six already existing study groups with existing data to investigate the complex effects of the built environment and pollution on cognition in later life.
Figure 1: Conceptual framework of the effects of the neighbourhood built environment on cognitive health in later life
+ = increase
– = decrease
The aim of this project is to provide a deeper understanding into how built environments can support cognitive health and reduce the risk of cognitive decline and dementia. This project will include a variety of neighbourhood-built environment attributes as well a built environment characteristics (e.g. natural environment and pollution). It will collect data from a large range of geographical locations in Australia and the UK.
The hypotheses established for the study can be seen below (Table 2)
Table 2: Study hypotheses of the effects of the built environment attributes on cognitive health in later life
This project includes several pre-existing studies involving older populations (Table 1).
Table 1: The pre-exisitng studies Australian and UK used within the EPOCH study
Models will be established that enable the synthesis of environmental measures across aging populations
Procedures will be developed that will allow data on built environments, natural environments, and pollution, to be integrated with country specific Geographical Information system (GIS) data. GIS is a database that geographic data (data for different locations) is combined with software tools that allow for managing, analysing, and visualising the data. Environmental data sets that have been collected using similar methods and the same operating procedures will be used to enhance comparability between Australia and the UK.
Air pollution maps will be developed. As no previous air pollution data has been produced this will be gathered. Two types of air pollution will be explored:
- General ambient air pollution – air pollution from a range of sources including traffic, industry, and nature
- Traffic-related air pollution – air pollution form cars, buses, and trucks
Noise pollution in the UK will be obtained from there previously developed noise map, published by Defra. In Australia no noise maps are available and therefore noise pollution will be assessed using proxy measures (e.g., train line densities, aerial distances to nearest busy road etc.,)
Investigating the impact of the neighbourhood-built environments and built environment-related environmental factor on cognitive health in later life
The total, indirect (effected by other factors), and direct (independent of other factors) effects of environmental factors on cognitive health in later life (Figure 1) will be assessed to determine their beneficial and harmful impacts. This study will look at whether recent environmental factors are associated with cognitive impairment or increased cognitive decline as well as the calmative effect over of exposure of the last 15 years. Looking at calmative exposure will allow us to investigate the direct and indirect effects of environmental factors on cognitive health. Older people who have moved within the last four years will be excluded from the study.
Lifestyle behaviours can be affected by the characteristics of the built and natural environment and pollution and have been linked to cognitive decline. Analyses that include measures for physical activity, social activity and mental activity will be conducted. Baseline measurements and follow up measurements of these characteristics will be integrated into our analytical framework and GIS and the indirect effects of the environment on cognitive health via lifestyle behaviours will be estimated
Sex, genetics, and socio-economic status
The study will investigate whether the same environmental factors have different effects men and women and people with different socio-economic status (measured by education, occupation, or income). We will also examine the modifying effect of the APOE genotype, a known genetic risk factor for dementia, on the level of vulnerability to adverse environmental conditions
Integration and investigation of cross-country relationships
Results from different studies will be integrated using a program that synthesis the data. This will allow us to investigate any variation in data across countries and any region-specific effects
Benefits to society
This study will explore the total, indirect (mediated by other factors), and direct (independent of other factors) effects of the environmental factors on changes in cognitive health. This information is important as it can help identify pathways for prevention that may help lessen the negative effects, and has several policy implications.
For example, as densification (increase in population) is the main driver of other environmental changes (Figure 1) it is important to understand its total (direct plus indirect) impact on cognitive health to inform regulatory urban planning policies.
It is also necessary to estimate the direct and indirect effects of densification on cognitive health to distinguish between its potentially beneficial and harmful effects and identify pathways that lessen the the harmful effects, such as transportation policies that reduce air and noise pollution by limiting motorized traffic in residential areas.
Status / Timeline
The study period for this project is from October 1st 2020 to September 30th 2023.
Key Investigators (as per grant application)
• Prof Ester Cerin, ACU (Melbourne, Australia)
• Prof Fiona Matthews (Newcastle Uni, UK)
• Prof Kaarin Anstey, (UNSW)
• Prof Perminder Sachdev (UNSW)
• Dr Suzanne Mavoa (UoM)
• A/Prof Luke Knibs (UQ)
• Prof Bin Jalaludin, UNSW (Sydney, Australia)
• Dr Yu-Tzu Wu (Newcastle Uni, UK)
• Dr Matthew Prina (KCL, UK)
• Dr Benjamin Barratt (ICL, UK)
Associate Investigators and Research Staff
• Dr Amanda Wheeler (ACU)
• Prof Rachel Franklin (Newcastle Uni, UK),
• Dr Sean Beevers (ICL, UK)
• Prof Takemi Sugiyama (Swinburne Uni)
• Dr Victoria Houlden (Newcastle Uni, UK)
• Dr Yih-Kai Chan (ACU)
• Dr Miguel Alvardo Molina (ACU)
• Ms Nerolie Stickland (ACU)
The EPOCH Research Project is funded by the 2019 UKRI-NHMRC Built Environment Prevention Research Scheme