Urban green infrastructure size, quality and proximity and health outcomes in older populations

Background A city's multi-functional network of green and blue spaces has an important role underpinning the health and wellbeing of its residents. Although evidence of positive links between nature and health is plentiful, little is known about which particular aspects of green and blue spaces are most influential, and how benefits might vary between social groups and age. Methods We used a green infrastructure (GI) approach combining a high-resolution spatial dataset of land-cover and function with area-level demographic and socio-economic data. A comprehensive characterisation of the Greater Manchester UK city region was generated. The GI attributes were used in step-wise multi-level regression analyses to test for associations between population chronic morbidity and the functional, physical and spatial components of GI across an urban socio-demographic gradient. Results Individual GI attributes were significantly associated with health in all socio-demographic contexts; even when associations between health and overall green cover were non-significant. For areas with having higher proportions of older people ('older neighbourhoods'), associations were found between health and land-cover diversity, informal greenery and patch size in high income areas. In lower income areas, health was predicted by proximity to public parks and recreation land. Conclusions A nuanced description of greenspace in terms of quality, cover type, diversity explains more variation in population health than a single metric such as percentage green cover. People in urban neighbourhoods that have older age populations and lower income are disproportionately healthy if their neighbourhoods contain accessible, good quality public greenspace. This has implications for strategies to decrease health inequalities and inform international initiatives, such as the World Health Organisation's Age-Friendly Cities programme. Key messages A nuanced description of green and blue space in terms of quality, cover type, diversity explains more variation in population health than a single metric such as percentage green cover. People in urban neighbourhoods that have older age populations and lower income are disproportionately healthy if their neighbourhoods contain accessible, good quality public greenspace