Environmental influences on mental health: eight-year longitudinal data show a bi-directional association between residential mobility and mental health outcomes.

Evidence on the environmental determinants of mental health is often cross-sectional. This pre-registered longitudinal study examines the environmental determinants of mental health using eight years of data from the New Zealand Attitudes and Values Study. Among 44,051 adults, findings reveal age, body mass index, and exercise as key individual-level factors impacting mental health, while residential mobility and area-level deprivation emerged as key environmental-level determinants. Increased probability of moving correlates with higher prevalence of depression and anxiety, with subsequent moves worsening area-level deprivation for those with persistent mental health issues. Our findings underscore the significance of environmental factors for mental health, offering insights for population-level interventions.