Associations of ambient particulate matter and household fuel use with chronic liver disease in China: A nationwide analysis

Background

Long-term effects of outdoor and indoor air pollution on chronic liver disease (CLD) remain unclear. Thus, the study was conducted to investigate the relationship between prolonged exposure to ambient particulate matter (PM₁, PM_2.5 and PM₁₀) and household fuel usage with CLD.

Methods

Data from the China Health and Retirement Longitudinal Study (CHARLS) covering the years 2011 to 2020 were employed. In the cross-sectional analysis, 16,680 participants were included, while 12,969 participants were enrolled in the longitudinal study. The associations between various sizes of particulate matter and CLD were elucidated using logistic regression model and generalized linear-mixed models. Additionally, the additive effects of ambient particulate matter (PM) levels and the utilization of solid fuels for cooking were investigated, with a comparison of effect sizes between converted and non-converted fuel types.

Results

Over a 10-year follow-up period, 746 (5.75 %) individuals developed CLD. For a 1-year average concentrations, PM₁, PM_2.5 and PM₁₀ were each linked to a 1.549 (95 %CI:1.522–1.576), 1.296 (95 %CI:1.276–1.317) and 1.134 (95 %CI:1.118–1.150) fold risk of incident CLD per 10 μg/m³ increase, respectively. A similar effect of PM concentrations over a 2-year period on CLD was observed. Moreover, simultaneous exposure to ambient PM and solid fuels is associated with an increased risk of CLD. Those who continue using solid fuels may face a higher risk of CLD compared to individuals who switch to cleaner cooking fuels. Female participants, smokers, and individuals with shorter sleep duration and multiple chronic diseases exhibited slightly stronger effects.

Conclusion

Long-term exposure to various sizes of PM (PM_1, PM_2.5, PM₁₀) has been linked to an elevated risk of CLD incidence. Co-exposure to ambient PM and solid fuels is associated with higher health risks.