Table 1.
Characteristic | Control | Cases
|
|||||||
---|---|---|---|---|---|---|---|---|---|
Total | Subtypes a
|
p-value * | |||||||
(n = 938)
|
(n = 960)
|
ER+ b (n = 778)
|
ER-/PR-/HER2-(n = 182)
|
||||||
n | % | n | % | n | % | n | % | ||
Age (years) | |||||||||
20-29 | 25 | 2.7% | 22 | 2.3% | 15 | 1.9% | 7 | 3.8% | |
30-34 | 86 | 9.2% | 77 | 8.0% | 55 | 7.1% | 22 | 12.1% | |
35-39 | 267 | 28.5% | 257 | 26.8% | 199 | 25.6% | 58 | 31.9% | |
40-44 | 560 | 59.7% | 604 | 62.9% | 509 | 65.4% | 95 | 52.2% | 0.05 |
Reference (years) | |||||||||
2004-2005 | 306 | 32.6% | 273 | 28.4% | 212 | 27.2% | 61 | 33.5% | |
2006-2007 | 360 | 38.4% | 330 | 34.4% | 273 | 35.1% | 57 | 31.3% | |
2008-2010 | 272 | 29.0% | 357 | 37.2% | 293 | 37.7% | 64 | 35.2% | 0.002 |
Race/ethinicity | |||||||||
Non-Hispanic white | 767 | 81.9% | 749 | 78.4% | 607 | 78.5% | 142 | 78.0% | |
African American | 34 | 3.6% | 49 | 5.1% | 32 | 4.1% | 17 | 9.3% | |
Asian/Pacific Islannder | 82 | 8.8% | 113 | 11.8% | 99 | 12.8% | 14 | 7.7% | |
Native American | 19 | 2.0% | 26 | 2.7% | 19 | 2.5% | 7 | 3.8% | |
Hispanic White | 35 | 3.7% | 18 | 1.9% | 16 | 2.1% | 2 | 1.1% | < 0.001 |
Missing | 1 | 5 | 5 | 0 | |||||
Education | |||||||||
High school or less | 98 | 10.4% | 113 | 11.8% | 89 | 11.4% | 24 | 13.2% | |
Post high-school/some college | 305 | 32.5% | 318 | 33.1% | 253 | 32.5% | 65 | 35.7% | |
College graduate | 354 | 37.7% | 352 | 36.7% | 283 | 36.4% | 69 | 37.9% | |
Graduate/Professional school | 181 | 19.3% | 177 | 18.4% | 153 | 19.7% | 24 | 13.2% | 0.5 |
First-degree family history of breast cancer | |||||||||
No | 814 | 89.9% | 742 | 80.0% | 602 | 80.3% | 140 | 78.7% | |
Yes | 91 | 10.1% | 186 | 20.0% | 148 | 19.7% | 38 | 21.3% | < 0.001 |
Missing | 33 | 32 | 28 | 4 | |||||
BMI (kg/m2) | |||||||||
<25.0 | 532 | 57.0% | 571 | 59.7% | 473 | 61.0% | 98 | 54.1% | |
25.0-29.9 | 232 | 24.8% | 226 | 23.6% | 182 | 23.5% | 44 | 24.3% | |
≥30.0 | 170 | 18.2% | 159 | 16.6% | 120 | 15.5% | 39 | 21.5% | 0.2 |
Missing | 4 | 4 | 3 | 1 | |||||
Duration of oral contraceptives use (years) | |||||||||
Never | 103 | 11.0% | 107 | 11.2% | 92 | 11.9% | 15 | 8.4% | |
<5.0 | 338 | 36.1% | 340 | 35.7% | 281 | 36.3% | 59 | 33.0% | |
5.0-9.9 | 218 | 23.3% | 194 | 20.4% | 155 | 20.0% | 39 | 21.8% | |
≥10 | 276 | 29.5% | 312 | 32.7% | 246 | 31.8% | 66 | 36.9% | 0.3 |
Missing | 3 | 7 | 4 | 3 | |||||
Parity number | |||||||||
Nulliparous | 191 | 20.4% | 259 | 27.0% | 209 | 26.9% | 50 | 27.5% | |
1 | 193 | 20.6% | 192 | 20.0% | 158 | 20.3% | 34 | 18.7% | |
2 | 365 | 38.9% | 351 | 36.6% | 283 | 36.4% | 68 | 37.4% | |
≥3 | 189 | 20.1% | 157 | 16.4% | 127 | 16.3% | 30 | 16.5% | 0.05 |
Missing | 0 | 1 | 1 | 0 | |||||
Age at first livebirth among parous women (years) | |||||||||
<25 | 218 | 29.2% | 225 | 32.2% | 168 | 29.6% | 57 | 43.2% | |
25-29 | 225 | 30.1% | 222 | 31.8% | 187 | 33.0% | 35 | 26.5% | |
30-34 | 204 | 27.3% | 173 | 24.7% | 143 | 25.2% | 30 | 22.7% | |
≥35 | 100 | 13.4% | 79 | 11.3% | 69 | 12.2% | 10 | 7.6% | 0.04 |
Missing | 0 | 2 | 2 | 0 | |||||
Age at menarche (years) | |||||||||
<12 | 190 | 20.3% | 214 | 22.3% | 170 | 21.9% | 44 | 24.2% | |
12-13 | 519 | 55.4% | 538 | 56.1% | 438 | 56.4% | 100 | 54.9% | |
≥14 | 227 | 24.3% | 207 | 21.6% | 169 | 21.8% | 38 | 20.9% | 0.6 |
Missing | 2 | 1 | 1 | 0 | |||||
Alcohol consumption (average number of alcohol drinks / week) | |||||||||
Never | 227 | 24.3% | 220 | 23.1% | 175 | 22.7% | 45 | 24.9% | |
0-1.4 | 234 | 25.1% | 223 | 23.4% | 189 | 24.5% | 34 | 18.8% | |
1.4-3.7 | 235 | 25.2% | 245 | 25.7% | 196 | 25.4% | 49 | 27.1% | |
≥3.7 | 237 | 25.4% | 265 | 27.8% | 212 | 27.5% | 53 | 29.3% | 0.6 |
Missing | 5 | 7 | 6 | 1 | |||||
Ever had a screening mammogram | |||||||||
Never | 478 | 51.0% | 399 | 41.6% | 315 | 40.5% | 84 | 46.2% | |
Ever | 460 | 49.0% | 561 | 58.4% | 463 | 59.5% | 98 | 53.8% | <0.001 |
Abbreviations: BMI, body mass index. ER, estrogen receptor. PR, progesterone receptor. HER2, human epidermal growth factor receptor 2.
Chi-squared.
ER-/HER2+ were excluded because of limited number (60 cases).
Regardless of PR/HER2 status.