Table 1. Characteristics of sisters in the New York site of the BCFR.
| Characteristics | Affected | Unaffected | ||
| Sisters, N (%) | Sisters, N (%) | |||
| Age at blood donation, Mean (SD) | 49.2 (11.5) | 47.4 (11.2) | ||
| Race/Ethnicity | White | 208 (63.0) | 236 (57.8) | |
| Hispanic | 84 (25.5) | 121 (29.7) | ||
| Other | 38 (11.5) | 51 (12.5) | ||
| Menopausal status | Pre- | 116 (35.6) | 257 (66.1) | |
| Post- | 210 (64.4) | 132 (33.9) | ||
| BMI, Mean (SD) | 25.5 (5.0) | 25.5 (4.9) | ||
| BMI status | <25 | 172 (52.1) | 217 (53.7) | |
| ≥25 | 158 (47.9) | 187 (46.3) | ||
| Number of cigarettes per day*, Mean (SD) | 13.9 (10.0) | 13.0 (10.7) | ||
| Smoking pack years*, Mean (SD) | 13.3 (16.2) | 10.9 (12.7) | ||
| Smoking status | Never | 196 (58.9) | 235 (57.5) | |
| Former | 121 (36.3) | 123 (30.1) | ||
| Current | 16 (4.8) | 51 (12.4) | ||
| Ever drink alcohol | No | 189 (57.1) | 230 (56.4) | |
| Yes | 142 (42.9) | 178 (43.6) | ||
| HRT# use | Never | 281 (85.9) | 322 (81.3) | |
| Ever | 46 (14.1) | 74 (18.7) | ||
| Duration of HRT# use (years) | 5.3 (7.1) | 5.4 (7.3) | ||
| OC use** | Never | 126 (37.9) | 158 (39.0) | |
| Ever | 206 (62.1) | 247 (61.0) | ||
| Duration of OC** use (years) | 4.8 (4.6) | 5.0 (4.5) | ||
| Benign breast disease | Never | 196 (60.9) | 255 (64.6) | |
| Ever | 126 (39.1) | 140 (35.4) | ||
*
Among ever smokers;
#HRT: Hormone replacement therapy;
**
OC: Oral contraceptive.