The number of people worldwide living with dementia and cognitive impairment is increasing, mainly due to people living longer, so we want to figure out how where we live affects dementia and brain health as we get older. Some research suggests that where we live might influence our brain health. For example, poor air quality in towns and cities, can lead to a decline in brain health. As more of us now live in towns and cities, it is important that the environment where we live is scientifically designed and improved to maximise our brain health. The complex social and physical environments where we live make some people more vulnerable than others to developing cognitive impairment. In other words, the factors that account for who is most likely to develop cognitive ill-health due to the environment has less to do with 'how' we live and more to do with 'where' we live. We do not know how these factors interact to make urban environments a problem for brain health, nor which are the best policies and interventions for promoting healthy ageing and brain health for our poorest communities. Our project will provide evidence for policies and practices that provide supportive urban environments to promote healthy ageing, including promoting brain health. This could include using creative urban designs to support people to adopt and maintain healthier lifestyles such as being more active. However, this needs a strong evidence base with expert community advocates who can articulate how supportive urban environments can improve brain health. Our research has the following steps: 1. First, with the help of stakeholders, including those from business, industry, and local government, and a review of existing research, we will represent the relationships between our biology, our lifestyles and our environment in a diagram illustrating how they likely interact to affect brain health, because visual thinking can help stakeholders better identify possible intervention sweet-spots to improve brain health. 2. By analysing data from over 8,000 older people in Northern Ireland, and linking this to information about where they live, such as the amount of air pollution, the toxins in soil, or how walkable their neighbourhoods are, we will explore how different environmental factors relate to brain health. 3. Next, we will collect new data on a subgroup of 1,000 older people including more in-depth measures of brain health and better measures of physical activity, using GPS devices worn around the waist that monitor our locations. This will allow us to explore how the urban environment influences our brain health. 4. Then, we will explore how aspects of our biology play a role in how the urban environment affects our brain health. 5. We will host workshops with local citizens to 'sense-check' our findings and co-develop promising prevention approaches. In these, we will explore the acceptability, affordability, feasibility and sustainability of new initiatives to improve the environmental influences on brain health. This might include, for example, policies on: expanding the car-free areas of the city to reduce air pollution; increasing the number of footpaths and cycle paths to encourage walking and cycling; improving public transport to reduce car use. As a result of our research we will produce: 1. A map of the system in which our genes, lifestyle behaviours and urban environments interact to affect brain health, to help guide stakeholders towards policies and programmes that can improve brain health. 2. An evidence base exploring how where we live affects our brain health. 3. A suite of potential policies and interventions to improve brain health and promote healthy ageing 'tested' (in terms of acceptability and feasibility) with older people, business, industry, policymakers and other stakeholders.

There is strong evidence that natural environments within urban areas, such as parks, woodlands, lakes and beaches, have positive impacts on health. These urban green and blue spaces (UGBS) could be huge assets for protecting and equalising health if they were available, accessible, valued and well-used, particularly by less advantaged groups. The problem is that they are not. This is largely because the many policies, organisations and communities involved in designing, creating, managing, promoting, maintaining and using UGBS are disconnected. Also, the voices of less advantaged communities that UGBS could be helping most are either not heard or not persuasive. Perhaps as a consequence, those communities are much less likely to benefit from these spaces. We know that the UGBS we have are not the UGBS we need to make the best possible contribution to better and more equal health. GroundsWell aims to change that. We propose a new partnership - researchers working together with communities and those who currently create and control UGBS, to plan, design and manage it better so that it benefits everyone, especially those who need it most. The main research will take place in three cities - Belfast, Edinburgh and Liverpool. These have sufficient similarities (such as large and diverse low-income communities) but also distinct features (such as geography and culture) making them, collectively, an ideal laboratory. Each city already has policies and programmes in place to improve UGBS, but there is much room for improvement. GroundsWell will take a systems approach. This means understanding the multiple and interconnecting components of policy-making, practice, perception and people which together affect the presence, location, character and use of UGBS. It also means working to transform the system so that the components function together. To do this, GroundsWell will mix co-development of new theoretical frameworks, novel data science including simulation, health economics and policy analysis, but at its heart will be community engagement and partnership. We will develop and use meaningful community engagement, co-production and citizen science to understand the system, identify how and where it is broken, and co-create solutions. We anticipate interventions aimed at how the UGBS system operates, and small-scale interventions around actual spaces and their use. Data play an important part in understanding systems. GroundsWell will develop an accessible, trustworthy and policy-relevant system to collate, collect, house and share data on UGBS across the three cities. These data will be used to help the whole Consortium understand the UGBS there, identify possible interventions, and then assess whether they work, for whom and why, creating feedback loops to help us continually monitor, learn and adapt what we do. Novel simulation approaches will also be used to suggest interventions, and in particular what could be effective beyond the three cities. Health economics will suggest what would be best value for money. An important part of putting actions and solutions in place is understanding if they work (or not). Evaluation of our actions and the Consortium as a whole will be undertaken in partnership with our communities, drawing on the new data system we establish, and enabling them to directly see whether and how the process has benefited them. In particular, we will assess and share our impacts on health inequalities. We are realistic about the likely scale of our impacts. Small actions within existing UGBS and local communities are unlikely to affect population level health and inequalities within our funded period. That is why we are going to focus on improving the UGBS system as a whole, laying foundations for long-term benefits. We know that the use and enjoyment of UGBS is something that adults pass on to their children. If GroundsWell can improve and equalise the role of UGBS, it will achieve a lasting impact.