Lifetime urban exposure, socioeconomic position and respiratory health among adolescents.

INTRODUCTION

Early-life exposure to urban environmental factors, including air pollution, greenness or climate-related factors, is suspected to be associated with respiratory health but evidence among adolescents is scarce. We estimated the association between early-life exposure to urban factors and respiratory health among adolescents and addressed whether the socioeconomic position (SEP) could modify these associations.

METHODS

This study was based on 3731 mother-child pairs from the HELIX and Generation R cohorts with 29 exposures from 6 domains (air pollution, built environment, natural spaces, climate-related factors, road traffic, light and noise) assessed during pregnancy, early (1-6 years) and middle childhood (7-12 years). Ever-asthma, wheezing and lung function parameters were assessed in adolescents (13-18 years). Associations between urban exposure profiles, defined at each period separately, and respiratory health were estimated through regression models. Models were further stratified by SEP levels during pregnancy.

RESULTS

At each period, 2 exposure profiles were identified: high (high exposure to air pollutants, built environment, road traffic, noise and light and reduced access to green/blue spaces) vs. low urbanicity. High urbanicity in each period was associated with a lower risk of asthma and wheezing. SEP did not modify these associations. High urbanicity profile was associated with higher forced vital capacity (FVC) and forced respiratory volume in 1 s (FEV1) in the HELIX population and with higher FVC among adolescents with higher SEP.

CONCLUSION

These findings reflect the complex, context-dependent nature of the urban exposome, where both beneficial and harmful components coexist and interact in shaping respiratory health trajectories.