Table 1.
Distribution of demographic and major risk factors for breast cancer among cases and controls and by user/nonuser of any NSAID, the Nashville Breast Health Study, 2001–2010
| Participant Characteristics | Cases N (%) |
Controls N (%) |
P-value | Users among controls, N (%) |
Nonusers among controls, N (%) |
P-value |
|---|---|---|---|---|---|---|
| Demographics | ||||||
| Age (mean ± SD) | 52.7±10.9 | 54.4±10.5 | <0.001 | 56.8±10.2 | 50.4±10.7 | <0.001 |
| Race | ||||||
| Non-Hispanic white | 1951 (72.5) | 1961 (82.2) | 690 (84.2) | 1251 (81.1) | ||
| Non-Hispanic black | 663 (24.6) | 345 (14.5) | <0.001 | 108 (13.2) | 234 (15.2) | 0.124 |
| Other | 79 (2.9) | 78 (3.3) | 21 (2.6) | 57 (3.7) | ||
| Education | ||||||
| ≤High school | 988 (36.7) | 756 (31.7) | 289 (35.3) | 459 (29.8) | ||
| Some college | 705 (26.2) | 649 (27.3) | <0.001 | 233 (28.4) | 409 (26.5) | 0.001 |
| ≥College | 998 (37.1) | 978 (41.0) | 297 (36.3) | 674 (43.7) | ||
| Income per annum (US$) | ||||||
| ≤20,000 | 380 (14.1) | 195 (8.2) | 96 (11.7) | 98 (6.4) | ||
| 20,001–40,000 | 513 (19.0) | 388 (16.3) | 147 (18.2) | 236 (15.3) | ||
| 40,001–60,000 | 542 (20.1) | 553 (23.2) | <0.001 | 194 (23.7) | 351 (22.8) | <0.001 |
| >60,000 | 1159 (43.0) | 1183 (49.6) | 354 (43.2) | 822 (53.3) | ||
| Missing data | 100 (3.71) | 65 (2.7) | 26 (3.2) | 35 (2.3) | ||
| Postmenopausal | 1751 (65.3) | 1477 (62.1) | 0.019 | 645 (79.0) | 814 (52.9) | <0.001 |
| Major risk factors | ||||||
| Age at menarche (yrs, mean ± SD) | 12.6±1.6 | 12.5±1.6 | 0.181 | 12.5±1.6 | 12.7±1.6 | 0.007 |
| Parity | ||||||
| 0 | 421 (15.7) | 380 (16.0) | 121 (14.5) | 252 (16.3) | ||
| 1 | 489 (18.2) | 431 (18.1) | 140 (17.1) | 289 (18.7) | ||
| 2 | 988 (36.7) | 886 (37.2) | 0.958 | 284 (34.7) | 594 (38.5) | 0.005 |
| ≥3 | 791 (29.4) | 686 (28.8) | 274 (33.5) | 407 (26.4) | ||
| Age at first live birth (yrs) a | ||||||
| ≤20 | 766 (33.8) | 561 (28.0) | 246 (35.2) | 313 (24.3) | ||
| 21–25 | 743 (32.8) | 721 (36.0) | 254 (36.4) | 460 (35.7) | ||
| 26–30 | 486 (21.4) | 482 (24.1) | <0.001 | 139 (19.9) | 338 (26.2) | <0.001 |
| >30 | 273 (12.0) | 239 (11.9) | 59 (8.5) | 179 (13.9) | ||
| Ever use of hormone replacement therapy | 1134 (42.2) | 946 (39.7) | 0.076 | 442 (54.0) | 493 (32.0) | <0.001 |
| BMI (kg/m2) | ||||||
| <25 | 967 (36.0) | 999 (42.0) | 265 (32.4) | 722 (46.9) | ||
| ≥25 | 1718 (64.0) | 1380 (58.0) | <0.001 | 553 (67.6) | 817 (53.1) | <0.001 |
| Regular exercise | 1365 (50.8) | 1343 (56.4) | <0.001 | 451 (55.1) | 883 (57.3) | 0.298 |
| Regular alcohol consumption | 479 (17.8) | 471 (19.8) | 0.071 | 176 (21.5) | 292 (19.0) | 0.149 |
| Ever cigarette smoking | 1117 (41.5) | 975 (40.9) | 0.668 | 381 (46.5) | 585 (37.9) | <0.001 |
| Family history of breast cancer | 541 (20.1) | 332 (13.9) | <0.001 | 106 (12.9) | 224 (14.5) | 0.291 |
| Personal history of benign breast disease | 1186 (44.1) | 775 (32.5) | <0.001 | 298 (36.4) | 468 (30.4) | 0.003 |
a
Among parous women.