Table 1.
Patient Characteristics
| Characteristic | Aspirin Non-Users N = 20889 |
Aspirin Users N = 5111 |
P * |
|---|---|---|---|
| Age, mean (SD) | 55.3 (10.2) | 65.3 (9.8) | <0.0001 |
| Age categories, no. (%) | |||
| 40-49 | 7425 (35.6) | 359 (7.0) | |
| 50-59 | 6824 (32.7) | 1120 (21.9) | <0.0001 |
| 60-69 | 4718 (22.6) | 1940 (38.0) | |
| ≥70 | 1922 (9.2) | 1692 (33.11) | |
| BMI, mean (SD) | 28.5 (7.2) | 30.4 (7.6) | <0.0001 |
| BMI, categories, no. (%) | |||
| <18.5 | 351 (1.7) | 48 (0.9) | |
| 18.5-24 | 7462 (35.7) | 1282 (25.1) | |
| 25-29 | 5774 (27.6) | 1509 (29.5) | <0.0001 |
| 30-34 | 3745 (17.9) | 1076 (21.1) | |
| ≥35 | 3557 (17.0) | 1196 (23.4) | |
| Race | |||
| White | 11125 (53.3) | 2394 (46.8) | |
| African American | 8158 (39.1) | 2504 (49.0) | <0.0001 |
| Other | 1606 (7.7) | 213 (4.2) | |
| Breast density, no. (%) | |||
| BI-RADS 1 | 2006 (9.6) | 861 (16.9) | |
| BI-RADS 2 | 9346 (44.7) | 2859 (55.9) | <0.0001 |
| BI-RADS 3 | 8480 (40.6) | 1312 (25.7) | |
| BI-RADS 4 | 1057 (5.1) | 79 (1.6) |
*
Student’s t-test was used for continuous variables, and the chi-squared test for categorical variables. All tests were two-sided.