The District Decides: How the Well-Being of the District Affects the Psyche of Children from 3 to 17 Years Old

Researchers from Imperial College London followed nearly 3,600 participants in the UK Millennium Cohort Study from ages 3 to 17 and showed that the socioeconomic level of the area is the strongest “external” factor associated with mental health, with its influence increasing in adolescence. The impact of PM2.5 (fine air particles) is more noticeable in early childhood (around 3 years old), and the benefits of “simply” greenery are less clear after taking into account other factors. The work was published on April 1, 2025 in JAMA Network Open.

What was studied

• Data from the UK Millennium Cohort Study: 3595 children living in England and followed from 3 to 17 years of age.
• We compared the scores on the SDQ questionnaire (behavioural and emotional difficulties) with the characteristics of the area of residence at different age points:
  • Socio-economic status of the area (Index of Multiple Deprivation, IMD).
  • Air pollution: PM2.5, PM10, NO₂ (by residential address).
  • Green environment: satellite "greenness index" (NDVI) and park/field area.
• Analysis is hierarchical Bayesian regression taking into account individual and family factors.

Key findings

• Socioeconomics is the strongest factor. Living in a wealthier area is associated with lower SDQ scores (i.e., better mental health), and by age 17 this effect is significantly stronger than at age 5.
  • The difference in log-SDQ between the most affluent and the most deprived areas was -0.31 (95% CI -0.45…-0.17) at 5 years and -0.73 (-0.88…-0.58) at 17 years.
• Air is especially important at 3 years. Every +1 μg/m³ PM2.5 at 3 years is +0.15 to the log-SDQ (95% CI 0.08…0.22), i.e. worse indicators. Similar signals for PM10 and NO₂. At older ages, the connection weakens.
  • Despite an overall decrease in concentrations over 2004–2017, levels remained above WHO recommendations.
• Greenery — no clear effect. Neither NDVI nor park area were consistently associated with better SDQ scores. Only gender differences were found: for boys, greenery was more often a positive factor (interaction around -0.10), but not for girls.
• Why is age-specific "linking" important? Models of "cumulative" (average over years) exposure smoothed out and masked age-specific peaks in exposure (especially for air at 3 years).

What does this mean in practice?

For cities and politics

• Reduce background PM2.5/NO₂ levels precisely where children live and study: “clean” routes to schools and kindergartens, restrictions on transit transport near educational institutions, green buffers along highways, and stricter emission standards.
• Targeted measures in disadvantaged areas: access to psychological support and leisure, safe public spaces, programs against domestic stress and violence - this will give a greater benefit than simply planting trees.
• When planning greening, consider quality and accessibility (paths, lighting, safety, sections), and not just the number of green pixels on the map.

For families

• At an early age, try to minimize contact with exhaust fumes: choose a route to the kindergarten/doctor away from busy roads, ventilate outside of rush hour, use air filtration in the home/nursery.
• Monitor the “base”: sleep patterns, movement, nutrition, screens – these are factors that SDQ “feels” no worse than its surroundings.

Important Disclaimers

• The SDQ is a questionnaire, not a clinical diagnosis; greenness assessments did not take into account quality/safety or actual use of spaces.
• The exhibits were counted by home address - the school and routes could differ.
• The sample overrepresents wealthier families and whites; the results are about England and its context.

Conclusion

Mental health of children and adolescents is not only "parks and paths". The main levers are reducing poverty and stress in the area, plus protecting the little ones from dirty air. And green infrastructure works when it is safe, accessible and in demand - and is built into school and yard life, and not just drawn on a map.

Source: Shoari N, Blangiardo M, Pirani M. Neighborhood Characteristics and Mental Health From Childhood to Adolescence. JAMA Network Open. 2025;8(4):e254470.