Breast cancer incidence in relation to long-term low-level exposure to air pollution in the ELAPSE pooled cohort
Menée à l'aide de données européennes portant sur 199 719 personnes, cette étude analyse l'association entre une exposition à long terme à la pollution de l'air (dioxyde d'azote, particules fines PM2.5, carbone, ozone) et le risque de cancer du sein (9 659 cas)
Résumé en anglais
Background: Established risk factors for breast cancer include genetic disposition, reproductive factors, hormone therapy, and lifestyle-related factors such as alcohol consumption, physical inactivity, smoking, and obesity. More recently a role of environmental exposures, including air pollution, has also been suggested. The aim of this study, was to investigate the relationship between long-term air pollution exposure and breast cancer incidence.
Methods: We conducted a pooled analysis among six European cohorts (n=199,719) on the association between long-term residential levels of ambient nitrogen dioxide (NO2), fine particles (PM2.5), black carbon (BC), and ozone in the warm season (O3) and breast cancer incidence in women. The selected cohorts represented the lower range of air pollutant concentrations in Europe. We applied Cox proportional hazards models adjusting for potential confounders at the individual and area-level.
Results: During 3,592,885 person-years of follow-up, we observed a total of 9,659 incident breast cancer cases. The results of the fully adjusted linear analyses showed a hazard ratio (95% confidence interval) of 1.03 (1.00, 1.06) per 10 μg/m³ NO2, 1.06 (1.01, 1.11) per 5 μg/m³ PM2.5, 1.03 (0.99, 1.06) per 0.5 10−5m−1 BC, and 0.98 (0.94, 1.01) per 10 μg/m³ O3. The effect estimates were most pronounced in the group of middle-aged women (50–54 years) and among never smokers.
Conclusions: The results were in support of an association between especially PM2.5 and breast cancer.
Impact: The findings of this study suggest a role of exposure to NO2, PM2.5 and BC in development of breast cancer.
