Table 2.
Demographic characteristics of the study population by breast cancer status
| Characteristics | Breast cancer cases (N=2,707) | Disease free (N=90,081) | p value* | ||
|---|---|---|---|---|---|
| Age in years, mean (SD) | 61.7 | (9.9) | 59.7 | (10.9) | <0.0001 |
| Body mass index in kg/m2, mean (SD) | 25.9 | (5.3) | 26.0 | (5.8) | 0.19 |
| n | (%) | n | (%) | ||
| Race | <0.0001 | ||||
| White | 2,206 | (93.1) | 51,733 | (87.6) | |
| African American | 56 | (2.4) | 1,719 | (2.9) | |
| Asian/Pacific Islander | 74 | (3.1) | 4,170 | (7.1) | |
| Other | 34 | (1.4) | 1,460 | (2.5) | |
| No information | 337 | 30,999 | |||
| Education | 0.10 | ||||
| Below high school | 223 | (9.6) | 5,177 | (9.7) | |
| High school/GED | 702 | (30.1) | 15,241 | (28.4) | |
| Some college | 770 | (33.0) | 18,643 | (34.8) | |
| College graduate | 284 | (12.2) | 7,075 | (13.2) | |
| Graduate school | 351 | (15.1) | 7,480 | (14.0) | |
| No information | 377 | 36,465 | |||
| Family history of breast cancer (1st or 2nd degree relatives) | <0.0001 | ||||
| No | 1,773 | (68.7) | 57,021 | (74.6) | |
| Yes | 808 | (31.3) | 19,418 | (25.4) | |
| No information | 126 | 13,642 | |||
| Parous | 0.39 | ||||
| No | 306 | (11.8) | 9,520 | (12.3) | |
| Yes | 2,291 | (88.2) | 67,572 | (87.7) | |
| No information | 110 | 12,989 | |||
| Diabetes | 0.23 | ||||
| No | 2,434 | (89.9) | 80,335 | (89.2) | |
| Yes | 273 | (10.1) | 9,746 | (10.8) | |
| Hormone therapy use | <0.0001 | ||||
| Never | 1,335 | (49.3) | 50,972 | (56.6) | |
| Estrogen only | 522 | (19.3) | 17,313 | (19.2) | |
| Estrogen plus progestin | 850 | (31.4) | 21,796 | (24.2) | |
| Menopausal status | <0.0001 | ||||
| Pre-menopausal | 23 | (0.9) | 3,661 | (4.2) | |
| Peri or Post-menopausal | 2,670 | (99.1) | 82,655 | (95.8) | |
| No information | 14 | 3,765 | |||
| Other lipid lowering agent use | <0.01 | ||||
| Never | 2,561 | (94.6) | 86,191 | (95.7) | |
| Ever | 146 | (5.4) | 3,890 | (4.3) | |
*
Chi square test for categorical variables or t-test for continuous variables