International Mind, Activities and urban Places (iMAP) study
Findings on the effects of urban environments on cognitive health derived from retrospectively adding environmental data to existing cohorts with cognitive functioning assessments (ExCoGIS initiative) have limitations. Limitations arise from the fact that these cohorts were not originally devised to examine the impact of urban design on cognitive health and, as such, their design and recruitment strategies are not optimal to answer these questions. Studies purposively designed to examine and disentangle the negative and positive influences of urban environments on cognitive health need to adopt a recruitment strategy that maximises the variability in environmental exposures and separates the effects of co-occurring urban attributes (e.g., density and traffic-related air-pollution). By recruiting participants from residential areas stratified by levels of socio-economic status, transport-related walkability and traffic-related pollution from cities varying in levels of exposures, lifestyle behaviours and prevalence of dementia, the iMAP study will allow a robust estimation of dose-response relationships of urban design and its by-products with brain and cognitive health. By employing a common research protocol and comparable measures, iMAP will also make it possible to investigate whether the effects of urban environments on cognitive health are generalizable across geographical locations and cultures.
The aim of the iMAP study is to examine the extent to which, how, and for whom aspects of the urban environment influence cognitive health in mid-aged and older community dwellers living in Melbourne (Australia), Barcelona (Spain) and Hong Kong (China). In order to increase the diversity of environmental data included in our analyses, we will seek to establish iMAP studies in other cities across the globe.
Through iMAP we will examine (1) the associations of physical and social attributes of the participants’ neighbourhood environment and other activity locations with changes in cognitive function and brain health; (2) the extent to which these changes are explained by lifestyle behaviours (physical activity, sedentary time, quality of sleep, social and cognitive activities); (3) and the extent to which the observed associations depend on personality traits and genetic predisposition to dementia.
Ecological model of the effects of urban environments on cognitive health
At present, the iMAP study will be conducted in three locations: Melbourne (Australia), Barcelona (Spain) and Hong Kong (China).
Each of the three study sites will recruit random samples of 600 mid-age and older (50-79 years) non-demented community dwellers, able to walk, and residing in pre-selected areas in Melbourne, Barcelona and Hong Kong (total N=1,800) stratified by area-level socio-economic status, walkability and traffic-related air pollution. This recruitment strategy will enable us to maximise the variability of key environmental attributes of interest within each study site.
Procedures and Measures
Data collection on all participants will include:
- Two face-to-face assessments (encompassing various aspects of cognitive functioning, physical functioning, habitual activity locations and their characteristics, etc.)
- A self-completed survey (including personality traits and household characteristics)
- A 7-day monitoring of lifestyle activities (i.e., physical, social and cognitive activities, sleep, sedentary behaviour and navigational activities) and their locations, mobility behaviours (trips and modes of transport) and affective states
- The objective assessment of the environment using both GIS and direct observation data (including aspects of the environment listed in the ExCoGIS initiative).
- A subsample of 700 participants will be subsequently invited to undertake Magnetic Resonance Imaging (MRI) brain scans to assess the volume of various regions of the brain, brain connectivity and other parameters associated with inflammation, cardiovascular disease, neurodegeneration and ageing.
A subsample of 700 participants will be subsequently invited to undertake Magnetic Resonance Imaging (MRI) brain scans to assess the volume of various regions of the brain, brain connectivity and other parameters associated with inflammation, cardiovascular disease, neurodegeneration and ageing.
The assessments will be repeated approximately 24 months after the baseline assessments (except for the collection of a DNA sample and the self-completion of a personality questionnaire).
More details about the methodology of the iMAP study can be found in our protocol paper published in BMJ Open (click here to access).
Participant recruitment for the Melbourne site commenced in May 2019. Data collection will be conducted in 2019/2020 and repeated after 24 months in 2021/2022.
- Prof Ester Cerin, ACU (Melbourne, Australia) and University of Hong Kong (Hong Kong, China)
- Prof Mark Nieuwenhuijsen, ISGlobal (Barcelona, Spain) and ACU (Melbourne, Australia)
- A/Prof Karen Caeyenberghs, ACU (Melbourne, Australia)
- A/Prof Anthony Barnett, ACU (Melbourne, Australia)
- Prof Takemi Sugiyama, ACU (Melbourne, Australia)
- Prof Nicola Lautenschlager, University of Melbourne (Melbourne, Australia)
- Prof Bin Jalaludin, UNSW (Sydney, Australia)
- Prof Basile Chaix, Sorbonne University (Paris, France)
- Dr Michael Ni, University of Hong Kong (Hong Kong, China)
- Prof Tatia Lee, University of Hong Kong (Hong Kong, China)
- A/Prof Linwei Tian, University of Hong Kong (Hong Kong, China)
- Juan Domingo Gispert or Carles Falcón, Barcelonaβeta Brain Research Center, Fundació Pasqual Maragall (Barcelona, Spain)
- Dr Rachel Tham, ACU (Melbourne, Australia)
- Dr Amanda Wheeler, ACU (Melbourne, Australia)
- Prof David Dunstan, ACU (Melbourne, Australia)
- Dr Govinda Poudel, ACU (Melbourne, Australia)
This study was funded by the Australian Catholic University. It is also supported by in-kind contributions from ISGlobal (Barcelona, Spain), the University of Hong Kong (Hong Kong, China) and members of the NHMRC-funded Centre for Air pollution, energy and health Research (CAR). Ester Cerin is supported by an ARC Future.