BACKGROUND: Exposure to ambient air pollution constitutes a significant risk factor for both chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD). However, its impact on the progression of respiratory-cardiovascular disease trajectories, particularly among individuals with COPD, remains unclear. This study aims to assess the associations of long-term air pollution exposure with the progression from a healthy state to the development of COPD, subsequent CVD, and mortality, utilizing a multi-state modeling framework.
METHODS: We included 318,282 participants from the UK Biobank who were free of COPD and CVD at baseline in this prospective cohort study. Annual average concentrations of particulate matter (PM₂.₅, PM₁₀) and nitrogen oxides (NO₂, NOₓ), derived from participant residential histories and data from the UK's Department for Environment, Food and Rural Affairs (DEFRA), were used to estimate long-term exposure. Multi-state models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for each 1 µg/m³ increase in air pollutant concentration in relation to disease transitions along the respiratory-cardiovascular trajectory.
RESULTS: During a median follow-up period of 13.5 years, 6901 participants developed COPD; 2207 of whom subsequently developed CVD, and 15,921 participants died. All pollutants were significantly associated with adverse transitions in the respiratory-cardiovascular disease trajectory, Adjusted HRs (95 % CIs) per 1 µg/m³ increase in pollutant exposure for the transition from COPD to CVD were: NO, 1.013(1.006,1.020); NO, 1.005(1.001,1.009); PM, 1.051(1.035, 1.068); and PM, 1.068(1.045,1.093). Subgroup analyses revealed greater risks among specific populations, particularly among female COPD patients (HR for PM₂.₅=1.106) and individuals aged ≥ 55 years (HR for PM₂.₅=1.132). 2X2.5 10
CONCLUSION: Chronic exposure to ambient air pollution, particularly PM₂.₅ and PM₁₀, is linked to an elevated risk of progression from COPD to CVD, thereby augmenting the overall burden of respiratory-cardiovascular diseases. These findings highlight the urgent need for effective air quality interventions to reduce pollution-related health impacts.
