Space Meets Time: A Life-Course Perspective on the Associations Between Neighborhood Environments and Mental Health Problems during Adolescence and Young Adulthood

Abstract

Mental health problems among young people are a pressing public health concern, with around 75% of lifetime mental disorders emerging before age 24. The residential neighborhood environment is increasingly found to be related to young people’s mental health. Few studies, however, have considered the temporal dynamics and multidimensional nature of the neighborhood environment, thereby potentially underestimating the complexities of its influence. This dissertation addressed this gap by investigating whether and how time-varying exposure to multiple physical (i.e., green space, air pollution, traffic noise) and social environmental characteristics (e.g., neighborhood socioeconomic deprivation, social fragmentation, disorder) contributes to the developmental trajectories of mental health problems during adolescence and young adulthood. Guided by the Life Course of Place framework, the dissertation comprises four empirical chapters that evaluate six theoretical pathways through which neighborhood environments may exert long-term effects on young people’s mental health, using longitudinal data from the TRAILS cohort (TRacking Adolescents’ Individual Lives Survey). Findings reveal that environmental exposures change over time, but the pattern of change depends on specific environmental characteristics, residential mobility, and developmental stage. It was also found that young people’s mental health may be shaped not only by their current neighborhood environments but also by those experienced earlier in life. Individual- and family-level factors may influence such long-term relationships, but may mainly function as confounders that affect both residential selection and mental health outcomes. Overall, this dissertation advances the Life Course of Place framework by demonstrating the pattern of environmental changes over adolescence and young adulthood and the complexities through which early-life environmental exposures contribute to young people’s mental health. Place-based interventions accounting for such potential long-term environmental influence may be effective for promoting young people’s mental health.