International Mind, Activities and urban Places (iMAP) study

The iMAP study addresses the growing concerns surrounding dementia and cognitive decline in an aging population.

Background

Findings on the effects of urban environments on cognitive health by adding environmental data to previous studies with cognitive functioning assessments (ExCoGIS initiative) have limitations. Limitations arise because these studies were not originally designed to examine the impact of urban design on cognitive health. Therefore, their design and recruitment strategies are not the best way to answer these questions.

Studies investigating urban environments’ impact on cognitive health should purposefully design recruitment strategies. Maximizing variability in environmental exposures and separating effects of co-occurring urban attributes, such as density and traffic-related air pollution, is essential.

The iMAP study recruits from residential areas based on 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. This allows a robust estimation of dose-response relationships of urban design and its by-products with brain and cognitive health.

iMAP, with a standardized research protocol and comparable measures, facilitates investigating if urban environments’ effects on cognitive health are generalizable across geographical locations and cultures.

Aim

The iMAP study investigates how the urban environment affects cognitive health in mid-aged and older residents of Melbourne (Australia), Barcelona (Spain), and Hong Kong (China). The focus is on understanding the extent and influencing factors. To increase the diversity of environmental data included in our analyses, we will seek to establish iMAP studies in other cities across the globe.

iMAP 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) 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

Study sites

 iMAP is being conducted in three locations: Melbourne (Australia), Barcelona (Spain) and Hong Kong (China).

Participants

Each of the three study sites will recruit random samples of 600 mid-age and older (50-79 years). Participants will be cognitively healthy community dwellers, able to walk, and residing in pre-selected areas in Melbourne, Barcelona, and Hong Kong (total N=1,800). They will live in areas with differing area-level socio-economic status, walkability, and traffic-related air pollution. This recruitment strategy will enable the maximisation of 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 (assessing 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. This will assess the volume of various regions of the brain, brain connectivity and other parameters associated with inflammation, cardiovascular disease, neurodegeneration and ageing.

Assessments will be repeated approximately 24 months after the baseline assessments (excluding the collection of a DNA sample and the self-completion of a personality questionnaire).

Status/timeline

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.
* Due to Covid-19, the iMAP timeframe has been extended. Melbourne and Hong Kong completed baseline date collection in 2022 and repeated analysis is expected to be completed by the end of 2024. Analysis of baseline data has commenced.

Key Investigators

  • 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)

Funding Sources

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.

 

A more detailed decription of the study can be found in our iMAP Protocol paper, published in BMJ Open