Air Pollution Linked to Increased Psychotic Experience Risk in Adolescents

Air pollution exposure is associated with increased odds of psychotic experiences in adolescents, especially those living in urban environments, according to study data published in JAMA Psychiatry.

Investigators from the United Kingdom sought to determine whether an association exists between urban air pollution exposure and psychotic experiences in adolescents. Participants were members of the Environmental Risk (E-Risk) Longitudinal Twin Study conducted across England and Wales. Of the original sample, 2063 participants provided data on psychotic experiences, with 623 participants (30.2%) reporting at least 1 psychotic experience from age 12 to 18 years.

Pollution exposure estimates were modeled for 2012, when participants were 17 years of age. Estimates were linked with the latitudinal/longitudinal coordinates of participants’ residential addresses at the age of 18 years, as well as with 2 additional addresses where participants reported spending time, such as school or work. Pollutants included nitrogen dioxide, a regulated gaseous pollutant (NO₂); a regulated gaseous pollutant composed of NO₂ and nitric oxide (NO_x); and regulated pollutants composed of inorganic aerosols, carbonaceous aerosols, and dusts (PM_2.5 and PM₁₀). In addition, urbanicity was used in models to test whether air pollutants mediated the association between urban residency and adolescent psychotic experiences. Investigators measured urbanicity using the 2011 census data, which included combined residential density, output area, and contextual data.

Psychotic experiences were significantly more common in adolescents with the highest level of annual exposure to NO₂ (odds ratio [OR], 1.71; 95% CI, 1.28-2.28), NO_x (OR, 1.72; 95% CI, 1.30-2.29), and PM_2.5 (OR, 1.45; 95% CI, 1.11-1.90). Jointly, NO₂ and NO_x statistically explained 60% of the association between urbanicity and adolescent psychotic experiences.

There was no evidence of confounding by such covariates as family psychiatric history, maternal psychosis, childhood psychotic symptoms, or adolescent smoking and substance dependence.

Researchers noted that the measure of adolescent psychotic experiences was not clinically verified in their study; however, point estimates were similar for clinically verified psychotic symptoms

“In a rapidly urbanizing world, global efforts are needed to reduce air pollution levels and protect the mental (as well as physical) health of young urban citizens,” researchers concluded.

Reference

Newbury JB, Arseneault L, Beevers S, et al. Association of air pollution exposure with psychotic experiences during adolescence [published online March 27, 2019]. JAMA Psychiatry. doi: 10.1001/jamapsychiatry.2019.0056