Ambient air pollution exposure is associated with liver fat and stiffness in Latino youth with a more pronounced effect in those with PNPLA3 genotype and more advanced liver disease.

Background: Exposure to ambient air pollutants has emerged as a risk for metabolic-dysfunction associated steatotic liver disease (MASLD).
Objectives: We sought to examine associations between short-term (prior month) and long-term (prior year) ambient air pollution exposure with hepatic fat fraction (HFF) and liver stiffness in Latino youth with obesity. A secondary aim was to investigate effect modification by patatin-like phospholipase domain-containing protein 3 (PNPLA3) genotype and liver disease severity.
Methods: Data was analyzed from 113 Latino youth (age 11-19) with obesity in Southern California. Individual exposure to particulate matter with aerodynamic diameter ≤ 2.5μm (PM _2.5 ), ≤ 10μm (PM ₁₀ ), nitrogen dioxide (NO ₂ ), 8-hour maximum ozone (8hrMax-O ₃ ), 24-hr O ₃ , and redox-weighted oxidative capacity (O _x ^wt ) were estimated using residential address histories and United States Environmental Protection Agency air quality observations. HFF and liver stiffness were measured using magnetic resonance imaging. Linear models were used to determine associations between short-term and long-term exposure to air pollutants with HFF and liver stiffness. Modification by PNPLA3 and liver disease severity was then examined.
Results: Short-term exposure to 8hrMax-O ₃ was positively associated with HFF. Relationships between air pollution exposure and HFF were not impacted by PNPLA3 genotype or liver disease severity. Long-term exposure to 8hrMax-O ₃ and O _x ^wt were positively associated with liver stiffness. Associations between air pollution exposure and liver stiffness depended on PNPLA3 genotype, such that individuals with GG genotypes exhibited stronger, more positive relationships between short-term exposure to PM ₁₀ , 8hrMax-O ₃ , 24-hr O _3, and O _x ^wt and liver stiffness than individuals with CC/CG genotypes. In addition, relationships between short-term exposure to NO ₂ and liver stiffness were stronger in those with severe liver disease.
Discussion: Air pollution exposure may be a risk factor for liver disease among Latino youth with obesity, particularly in those with other preexisting risks for liver damage.
Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Rohit Kohli reports a relationship with Mirum Biopharma that includes: consulting or advisory. Rohit Kohli reports a relationship with Ipsen that includes: consulting or advisory. Michael Goran reports a relationship with YUMI foods that includes: consulting or advisory. Michael Goran reports a relationship with Bobbie Labs that includes: consulting or advisory. Michael Goran receives royalties from Penguin Random House for Sugarproof If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)