Chronic air pollution exposure ups MAFLD risk

Prolonged exposure to ambient air levels of particulate matter ≤1 µm (PM₁), ≤2.5 µm (PM_2.5), and ≤10 µm (PM₁₀), as well as of nitrogen dioxide (NO₂), appears to aggravate the likelihood of metabolic dysfunction-associated fatty liver disease (MAFLD), a recent study has found.

“We conducted an epidemiological study on the potential effect of ambient air pollution on the risk of MAFLD in approximately 90 thousand adults in China,” the researchers said. “We found that long-term exposure to ambient air pollution may increase the odds of MAFLD, especially in individuals who are male, smokers, and alcohol drinkers, those who consume a high-fat diet, and those with central obesity.”

The present cross-sectional study looked at 90,086 individuals, in whom MAFLD was diagnosed via radiological assessment of hepatic steatosis along with the presence of overweight/obesity, diabetes mellitus, or metabolic dysregulation. Exposure to air pollution was quantified using validated models.

Logistic regression analysis found that each 10-µg/m³ increase in exposure to PM₁, the odds of MAFLD increased by 13 percent (odds ratio [OR], 1.13, 95 percent confidence interval [CI], 1.10–1.17). A similar effect was reported for PM_2.5 (OR, 1.29, 95 percent CI, 1.25–1.34), PM₁₀ (OR, 1.11, 95 percent CI, 1.09–1.14), and NO₂ (OR, 1.15, 95 percent CI, 1.12–1.17).

Stratified analyses found that the link between PM_2.5 and MAFLD risk was stronger among individuals with high (OR, 1.90, 95 percent CI, 1.65–2.18) and low/moderate (OR, 1.35, 95 percent CI, 1.27–1.43) alcohol consumption, relative to never-drinkers (OR, 1.19, 95 percent CI, 1.12–1.26).

Other factors that modified the link between pollution exposure and MAFLD included smoking status, dietary fat intake, sex, and central obesity.