Association of fine particulate matter constituents with chronic obstructive pulmonary disease and the effect modification of genetic susceptibility

This study investigated the link between long-term exposure to PM_2.5 components and the risk of developing chronic obstructive pulmonary disease (COPD) using UK Biobank data. The exposure dataset, derived from the European Monitoring and Evaluation Program (EMEP) model, included elemental carbon (EC), organic matter (OM), ammonium (NH₄⁺), nitrate (NO₃⁻), and sulfate (SO₄²⁻). The risk of COPD was assessed using the Cox proportional hazards model, and the contribution of each component was evaluated with quantile g-computation. A polygenic risk score for COPD was used to explore genetic interactions with PM_2.5 constituents. Adjusted hazard ratios showed an increased risk for each component and the mixed exposure, with SO₄²⁻ (40.8%) contributing the most. We observed synergistic effects between genetic risk and exposure to PM_2.5, EC, NH₄⁺, and SO₄²⁻, accounting for 10–18% of total COPD risk. Prolonged exposure to PM_2.5, especially SO₄²⁻, increased the risk of COPD, with genetic factors modifying the effect.