The association between neighborhood built environment and mental health among older adults in Hangzhou, China.

In the context of population ageing, the age-friendliness of neighborhood built environment (NBE) is increasingly recognized as essential for enabling ageing in place. However, while much research has focused on the impact of NBE on the physical health of older adults, its relationship with mental health (MH) remains underexplored, especially the pathways through which NBE indicators influence MH. This study measured NBE using ten indicators across three categories: daily travel (including barrier-free travel, elevator, rest seat, diversion of pedestrian and vehicle, road surface and public toilet), healthcare services (including public canteen and elderly care), and social participation (including outdoor fitness space and indoor activity space). It examined the association between NBE and MH among 1405 older adults in Hangzhou, China, utilizing structural equation models to explore potential pathways. The findings revealed a significant and robust direct association between outdoor fitness spaces and MH of older adults. Additionally, physical health significantly mediated the association between road surface and MH, while social interaction played a crucial mediating role between public toilets, public canteens, elderly care, indoor activity spaces, and MH. Although the durations and types of leisure activities did not independently mediate the NBE-MH relationship, leisure durations effectively mediated it through both physical health and social interaction, whereas leisure types mediated it through social interaction. This study empirically supported the compensatory process and enabling process proposed by the ecological theory of aging, offering valuable empirical evidence to inform policies aimed at enhancing NBE to promote MH among older adults.