Table 2.

The risk of invasive breast cancer associated with PM2.5, PM10, and NO2

Breast cancerBreast cancer subtype
Control (N = 47,591)All cases (N = 1,749)ER+/PR+ (N = 947)ER/PR (N = 223)
Air pollutionMeanSDMeanSDHRa,b,c95% CIMeanSDRRb,c,d95% CIMeanSDRRb,c,d95% CIPe
PM2.5 10.52.410.52.41.030.96–1.1110.42.41.000.91–1.0910.52.50.990.81–1.200.99
PM10 22.25.822.26.00.990.98–1.0022.26.11.020.96–1.0921.95.40.960.83–1.100.69
NO2 10.14.710.34.71.020.97–1.0710.44.71.10 1.02–1.19 9.84.50.920.77–1.090.04
  • aEstimated using Cox proportional hazards.

  • bUnits representing an increase in the IQR difference: PM2.5 = 3.6 μg/m3; PM10 = 5.8 μg/m3; NO2 = 5.8 parts per billion (ppb).

  • cModels adjusted for age at diagnosis, race, educational attainment, smoking status, and menopausal hormone therapy.

  • dEstimated using polytomous logistic regression.

  • eTest of interaction in the polytomous regression model.