Table 3.
Multivariable rate ratios (95% confidence intervals) by menopausal status for inflammatory breast cancer (IBC), noninflammatory, locally advanced breast cancer with chest wall/skin involvement (LABC), and noninflammatory invasive breast cancer without chest wall/skin involvement (BC) vs control subjects*
| Variables | IBC | LABC | BC | |||
|---|---|---|---|---|---|---|
| Premenopausal (n = 182) | Peri/postmenopausal l (n = 435) | Premenopausal (n = 255) | Peri/postmenopausal l (n = 896) | Premenopausal (n = 1744) | Peri/postmenopausal (n = 5856) | |
| Demographic factors | ||||||
| Race/ethnicity | ||||||
| White non-Hispanic | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Black non-Hispanic | 1.72 (0.87 to 3.43) | 0.71 (0.43 to 1.16) | 1.87 (0.94 to 3.70) | 1.88 (1.35 to 2.63) | 1.01 (0.78 to 1.30) | 0.84 (0.72 to 0.98) |
| Other | 0.84 (0.36 to 1.95) | 0.55 (0.30 to 1.00) | 1.37 (0.75 to 2.51) | 0.89 (0.55 to 1.44) | 0.82 (0.65 to 1.05) | 0.67 (0.59 to 0.76) |
| Hispanic | 1.03 (0.49 to 2.15) | 1.19 (0.55 to 2.54) | 1.69 (0.95 to 3.01) | 1.14 (0.69 to 1.88) | 0.99 (0.78 to 1.25) | 0.77 (0.67 to 0.87) |
| Education | ||||||
| <High school diploma | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| High school or GED | 0.71 (0.20 to 2.51) | 0.54 (0.36 to 0.80) | 0.54 (0.24 to 1.23) | 0.79 (0.55 to 1.13) | 1.14 (0.80 to 1.63) | 0.95 (0.81 to 1.12) |
| Some college | 0.56 (0.19 to 1.63) | 0.72 (0.51 to 1.02) | 0.52 (0.26 to 1.05) | 0.89 (0.57 to 1.40) | 1.28 (0.89 to 1.84) | 0.93 (0.75 to 1.16) |
| College/postgraduate | 0.37 (0.14 to 1.03) | 0.47 (0.31 to 0.71) | 0.30 (0.15 to 0.61) | 0.68 (0.42 to 1.09) | 1.07 (0.79 to 1.45) | 0.89 (0.68 to 1.16) |
| Reproductive/ hormonal factors | ||||||
| Age at first birth, y | ||||||
| <20 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| 20–24 | 0.73 (0.30 to 1.81) | 0.80 (0.43 to 1.50) | 1.12 (0.46 to 2.74) | 1.09 (0.54 to 2.18) | 0.91 (0.60 to 1.36) | 0.89 (0.67 to 1.18) |
| 25–29 | 0.27 (0.10 to 0.75) | 1.00 (0.50 to 1.89) | 1.27 (0.60 to 2.70) | 0.93 (0.55 to 1.58) | 1.04 (0.75 to 1.46) | 0.98 (0.74 to 1.30) |
| ≥30 | 0.86 (0.32 to 2.34) | 0.43 (0.17 to 1.05) | 0.90 (0.37 to 2.19) | 1.03 (0.62 to 1.69) | 1.07 (0.66 to 1.72) | 1.08 (0.71 to 1.65) |
| Nulliparous | 0.67 (0.25 to 1.84) | 0.61 (0.31 to 1.19) | 1.14 (0.58 to 2.26) | 0.97 (0.49 to 1.91) | 0.72 (0.45 to 1.14) | 0.83 (0.51 to 1.34) |
| <30† | 0.85 (0.22 to 3.31) | 0.76 (0.18 to 3.13) | 1.21 (0.67 to 2.20) | 0.74 (0.41 to 1.35) | 0.91 (0.72 to 1.15) | 0.85 (0.64 to 1.14) |
| Height and body mass index (BMI) | ||||||
| Height, in | ||||||
| ≤62 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| 63–64 | 0.95 (0.49 to 1.85) | 1.20 (0.79 to 1.82) | 0.98 (0.64 to 1.52) | 0.96 (0.77 to 1.18) | 0.86 (0.73 to 1.01) | 1.08 (0.97 to 1.21) |
| 65–66 | 0.95 (0.49 to 1.84) | 1.38 (0.83 to 2.30) | 1.44 (0.87 to 2.35) | 0.94 (0.69 to 1.27) | 0.92 (0.76 to 1.11) | 1.06 (0.92 to 1.21) |
| ≥67 | 1.55 (0.55 to 4.36) | 1.50 (0.57 to 3.93) | 1.14 (0.67 to 1.94) | 1.22 (0.73 to 2.03) | 0.94 (0.80 to 1.12) | 1.15 (0.91 to 1.45) |
| BMI—premenopausal | ||||||
| <25 | 1.00 (referent) | — | 1.00 (referent) | — | 1.00 (referent) | — |
| 25–29.9 | 1.82 (0.88 to 3.77) | 1.04 (0.72 to 1.49) | 1.00 (0.81 to 1.23) | |||
| ≥ 30 | 3.62 (1.30 to 10.04) | 1.03 (0.59 to 1.81) | 0.98 (0.69 to 1.39) | |||
| BMI— peri/postmenopausal—noncurrent hormone users | ||||||
| <25 | — | 1.00 (referent) | — | 1.00 (referent) | — | 1.00 (referent) |
| 25–29.9 | 1.53 (0.95 to 2.46) | 1.13 (0.78 to 1.64) | 1.27 (1.11 to 1.45) | |||
| ≥30 | 3.75 (1.92 to 7.34) | 1.34 (0.76 to 2.36) | 1.41 (1.08 to 1.84) | |||
| BMI— peri/postmenopausal—current hormone users | ||||||
| <25 | — | 1.00 (referent) | — | 1.00 (referent) | — | 1.00 (referent) |
| 25–29.9 | 1.96 (1.00 to 3.86) | 1.00 (0.66 to 1.52) | 1.14 (0.94 to 1.39) | |||
| ≥30 | 3.20 (1.27 to 8.03) | 1.19 (0.70 to 2.03) | 1.23 (0.89 to 1.68) | |||
| Mammographic density | ||||||
| BI-RADS density‡ | ||||||
| 1 | 0.83 (0.23 to 2.99) | 0.50 (0.31 to 0.79) | 0.43 (0.10 to 1.85) | 0.70 (0.52 to 0.95) | 0.91 (0.60 to 1.39) | 0.59 (0.51 to 0.68) |
| 2 | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| 3 | 1.46 (0.91 to 2.36) | 2.14 (1.57 to 2.92) | 1.24 (0.82 to 1.87) | 1.31 (1.10 to 1.55) | 1.50 (1.28 to 1.77) | 1.37 (1.21 to 1.55) |
| 4 | 2.67 (1.41 to 5.05) | 3.23 (1.79 to 5.80) | 2.50 (1.64 to 3.80) | 1.93 (1.23 to 3.04) | 1.78 (1.43 to 2.20) | 1.88 (1.60 to 2.21) |
| Other factors | ||||||
| Breast cancer in female first-degree relative | ||||||
| No | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| Yes | 1.52 (0.93 to 2.50) | 1.59 (1.14 to 2.20) | 1.52 (0.91 to 2.53) | 1.35 (1.06 to 1.72) | 1.48 (1.27 to 1.71) | 1.37 (1.27 to 1.49) |
| Prior breast biopsy/fine needle aspiration | ||||||
| No | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) | 1.00 (referent) |
| yes | 1.33 (0.85 to 2.09) | 1.04 (0.76 to 1.41) | 1.33 (0.91 to 1.94) | 1.05 (0.87 to 1.26) | 1.20 (1.01 to 1.42) | 1.12 (1.05 to 1.20) |
* Using the multiple imputation method and conditional logistic regression models; each risk factor is adjusted for other risk factors in the table. Results for variables with statistically significant differences among the case groups are bolded.
† At certain centers, age at first birth was collected as < 30 years or ≥ 30 years.
‡ BI-RADS = breast imaging–reporting data system; 1 = Almost entirely fat; 2 = Scattered fibroglandular densities; 3 = Heterogeneously dense; 4 = Extremely dense.