Perinatal air pollution exposure and autism spectrum disorder severity: The intertwined roles of green space, grey space and healthcare accessibility - A cohort study.

This study looked at 237 children with autism to understand how air pollution during pregnancy and early life affects autism severity. Surprisingly, higher air pollution was linked to less severe autism symptoms, but this relationship changed based on nearby concrete surfaces and access to autism services. Most importantly, when children lived closer to autism support centers, air pollution didn't seem to matter for autism severity.

This cohort study examined how environmental factors during the first 1000 days of life influence the relationship between air pollution and autism severity. Analyzing 237 children with ASD from the ELENA cohort, researchers investigated perinatal PM2.5 and PM10 exposure alongside green spaces, grey spaces (impervious surfaces), and healthcare accessibility. Unexpectedly, higher PM exposure was associated with lower ASD severity, but this relationship was moderated by grey space coverage. Most significantly, healthcare accessibility emerged as crucial - when proximity to autism resource centers was considered, air pollution no longer predicted ASD severity.

The findings emphasize the complex interplay between environmental exposures and geographic factors in autism outcomes.

Healthcare accessibility appears more influential than environmental pollution in autism severity outcomes. Families and clinicians should prioritize proximity to autism resource centers. Urban planning considerations may need to account for complex pollution-environment interactions in autism support.

Single cohort study with moderate sample size (n=237). Paradoxical pollution findings require replication. Cross-sectional analysis cannot establish causation. Geographic specificity may limit generalizability to other regions.

Autism spectrum disorder (ASD) is influenced by environmental, genetic, and socio-economic factors. While air pollution exposure during development has been linked to ASD outcomes, the roles of green spaces, grey spaces, and healthcare accessibility in this relationship remain understudied. This research examines how these factors during the first 1000 days (from conception to the first two years of life), moderate the association between air pollution and ASD severity in children from the ELENA cohort ("Etude Longitudinale chez l'Enfant avec Autisme"). Data from 237 children with ASD were analyzed.

Perinatal exposure to particulate matter (PMand PM) was estimated using a validated model, with green spaces quantified using the normalized difference vegetation index (NDVI) and grey spaces through impervious surface coverage. Healthcare accessibility was measured as the distance to autism resource centers (CRA) from residential addresses. ASD severity was assessed using the total score of the Social Responsiveness Scale. Linear regression models within structural equation modeling estimated the effects of air pollution, green spaces, grey spaces, and healthcare accessibility on ASD severity.

Higher PM exposures were paradoxically associated with lower ASD severity. However, grey spaces significantly moderated this association, with greater impervious surface coverage attenuating the negative association. Healthcare accessibility was crucial: when considering center proximity, pollution was no longer associated with ASD severity. These findings highlight the critical role of healthcare accessibility and environmental factors in shaping the relationship between air pollution and ASD severity.

Integrating geographic and environmental contexts is crucial when evaluating the environmental determinants of ASD outcomes.