Table 2.
Hazard ratios (95% confidence intervals) of invasive breast cancer associated with body mass index and BI-RADS breast density stratified by race/ethnicity and menopausal statusa
| Risk factor | White | Black | Asian | Hispanic |
|---|---|---|---|---|
| Premenopausal | ||||
| Body Mass Index (kg/m2) | ||||
| Underweight (<18.5) | 0.94 (0.80, 1.10) | 1.53 (0.55, 4.29) | 0.96 (0.69, 1.35) | 0.65 (0.28, 1.54) |
| Normal (18.5–24.9) | 1 (referent) | 1 (referent) | 1 (referent) | 1 (referent) |
| Overweight (25.0–29.9) | 1.11 (1.05, 1.16) | 1.05 (0.79, 1.39) | 1.07 (0.91, 1.26) | 0.83 (0.70, 0.99) |
| Obese I (30.0–34.9) | 1.11 (1.04, 1.19) | 1.25 (0.93, 1.70) | 1.24 (0.89, 1.73) | 0.96 (0.78, 1.19) |
| Obese II/III (≥35.0) | 1.18 (1.09, 1.28) | 1.14 (0.81, 1.59) | 1.62 (0.96, 2.73) | 1.12 (0.86, 1.46) |
| BI-RADS Breast Density | ||||
| Almost entirely fat | 0.45 (0.38, 0.53) | 0.58 (0.35, 0.96) | 0.55 (0.24, 1.28) | 0.34 (0.19, 0.59) |
| Scattered fibroglandular densities | 1 (referent) | 1 (referent) | 1 (referent) | 1 (referent) |
| Heterogeneously dense | 1.66 (1.57, 1.74) | 1.45 (1.16, 1.83) | 1.56 (1.25, 1.93) | 1.80 (1.51, 2.14) |
| Extremely dense | 2.05 (1.91, 2.19) | 1.96 (1.39, 2.76) | 1.80 (1.43, 2.26) | 2.43 (1.94, 3.06) |
| Postmenopausal | ||||
| Body Mass Index (kg/m2) | ||||
| Underweight (<18.5) | 0.77 (0.68, 0.87) | 0.55 (0.23, 1.30) | 0.67 (0.48, 0.94) | 0.57 (0.29, 1.13) |
| Normal (18.5–24.9) | 1 (referent) | 1 (referent) | 1 (referent) | 1 (referent) |
| Overweight (25.0–29.9) | 1.26 (1.22, 1.30) | 1.25 (1.05, 1.48) | 1.45 (1.29, 1.63) | 1.13 (0.99, 1.28) |
| Obese I (30.0–34.9) | 1.41 (1.35, 1.46) | 1.56 (1.31, 1.86) | 1.51 (1.23, 1.85) | 1.31 (1.14, 1.51) |
| Obese II/III (≥35.0) | 1.43 (1.36, 1.50) | 1.76 (1.47, 2.11) | 2.21 (1.60, 3.05) | 1.37 (1.13, 1.66) |
| BI-RADS Breast Density | ||||
| Almost entirely fat | 0.56 (0.53, 0.59) | 0.65 (0.53, 0.80) | 0.60 (0.47, 0.76) | 0.54 (0.45, 0.65) |
| Scattered fibroglandular densities | 1 (referent) | 1 (referent) | 1 (referent) | 1 (referent) |
| Heterogeneously dense | 1.39 (1.35, 1.43) | 1.58 (1.41, 1.77) | 1.26 (1.12, 1.42) | 1.36 (1.21, 1.52) |
| Extremely dense | 1.62 (1.53, 1.72) | 1.69 (1.23, 2.31) | 1.49 (1.24, 1.78) | 2.06 (1.67, 2.54) |
a
All models adjust for age, BMI, and BI-RADS breast density.
Abbreviations: kg, kilograms; m, meters; BI-RADS, Breast Imaging Reporting and Data System.