NCT04574414: NeuroSmog

Determining the Impact of Air Pollution on the Developing Brain

Status unknown Last updated 5 October 2020

What this trial tests

trial testing Psychological testing and MRI imaging in Attention Deficit Hyperactivity Disorder in 800 participants. Status unknown.

Timeline

1 October 2020

Primary endpoint
31 December 2022

31 December 2023

Quick facts

Lead sponsor	Jagiellonian University
Status	Status unknown
Study type	OBSERVATIONAL
Enrollment	800
Start date	1 October 2020
Primary completion	31 December 2022
Estimated completion	31 December 2023
Sites	1 location across Poland

Drugs / interventions tested

• Psychological testing and MRI imaging

Conditions studied

• Attention Deficit Hyperactivity Disorder — all drugs for Attention Deficit Hyperactivity Disorder →
• Attention — all drugs for Attention →
• Executive Functioning — all drugs for Executive Functioning →
• Social Functioning — all drugs for Social Functioning →

Sponsor

Jagiellonian University

Who can join

Adults 10 to 13, any sex, with Attention Deficit Hyperactivity Disorder or Attention. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

* Background: Recent studies have linked exposure to airborne particulate matter (PM) to neurodevelopmental outcomes but the findings are mixed and mechanisms are unclear. We aim to determine the impact of PM on the developing brain of schoolchildren in Poland, a European country characterized by very high levels of air pollution. The investigators aim to determine the impact of PM on the developing brain of schoolchildren in Poland, a European country characterized by very high levels of air pollution.
* Study area: 19 towns in three voivodeships (Lesser Poland, Silesian, Opole) in the southern Poland. To reduce confounding by urbanicity and at the same time, to achieve sufficient contrasts in PM levels without too high logistic costs, towns were selected by size (big and small) and by PM levels (high, medium and low).
* Design: Case-control study with 800 children recruited over two school years, with two population controls per one ADHD case. Suspected cases will be recruited in specialized facilities and presumably ADHD-free children will be recruited in primary schools.
* Exposure assessment: Poland-wide PM and other air pollutants' grids will be created for the years 2006 to 2021 using statistical models to incorporate land use data, estimates from transport models, satellite observations and air pollution measurements from Polish monitoring network. Prenatal, early-life, lifelong and concurrent exposures will be calculated.
* Psychological testing: Every child and their parents will complete a series of psychological tests and interviews that will be conducted during their three visits to the recruitment facility.
* Neuroimaging: Each participant will undergo a Magnetic Resonance Imaging (MRI) scanning session that will be performed accordingly to the Human Connectome Adolescent Brain Cognitive Development project recommendations. Scanning will be performed on a single scanner in Krakow.

Publications & conference data

6 peer-reviewed publications reference this trial (live from Europe PMC):

1. NeuroSmog: Determining the Impact of Air Pollution on the Developing Brain: Project Protocol.
   Markevych I, Orlov N, Grellier J, Kaczmarek-Majer K, et al · · 2021 · cited 16× · PMID 35010570 · DOI 10.3390/ijerph19010310
2. The Impact of Early Life Exposure to Air Pollution on the Brain: A Diffusion MRI Study in 10-13-Year-Old Children With and Without ADHD Diagnosis.
   Lewandowska P, Bajada CJ, Mysak Y, Domagalik A, et al · · 2025 · cited 4× · PMID 40977578 · DOI 10.1002/hbm.70306
3. Family Functioning Style as a Predictor of the Quality of Cognitive Functioning of Primary School Students With ADHD.
   Walenista W, Izydorczyk B, Lipowska M, Markevych I, et al · · 2023 · cited 4× · PMID 36879510 · DOI 10.1177/10870547231158749
4. Association of Socioeconomic Status With IQ and Attention in School Children in Poland, a Country With Relatively Low Socioeconomic Differences.
   Compa M, Walczak B, Baumbach C, Kołodziejczyk J, et al · · 2025 · cited 1× · PMID 40534211 · DOI 10.1002/dev.70058
5. Behavioral Problems Among Young Adolescents in the Family and Neighborhood Context: a Case Control Study
   Sitnik-Warchulska K, Izydorczyk B, Markevych I, Baumbach C, et al · · 2024 · cited 1× · DOI 10.21203/rs.3.rs-3927506/v1
6. A Dyadic Perspective on ADHD: Adolescent-Parent Reports of Behavioural Problems and Family Functioning.
   Sitnik-Warchulska K, Izydorczyk B, Sawicki A, Markevych I, et al · · 2026 · PMID 41603676 · DOI 10.1002/cpp.70230