Table 2.
Distribution at baseline of selected characteristics by quintiles of DXA-derived whole body fat mass among non-cases (N = 10,457).
| Quintiles of whole body fat mass | |||||
|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | |
| N | 2113 | 2098 | 2095 | 2086 | 2065 |
| Age, mean | 63.5 | 63.7 | 64.0 | 63.3 | 61.8 |
| Family history of breast cancer (%) | 15.9 | 15.7 | 16.6 | 15.2 | 15.6 |
| History of diabetes (%) | 2.8 | 3.6 | 6.5 | 10.0 | 16.4 |
| Age at menarche (% <12 yrs) | 15.3 | 19.3 | 20.1 | 23.2 | 26.3 |
| Age at first full-term pregnancy (% ≥30 yrs) | 8.7 | 7.6 | 6.7 | 6.6 | 7.7 |
| Parity (mean) | 2.4 | 2.5 | 2.7 | 2.8 | 2.8 |
| Age at menopause, mean | 47.3 | 46.3 | 46.4 | 46.1 | 45.4 |
| Oral contraceptive use (% ever) | 38.1 | 37.3 | 35.9 | 36.7 | 38.3 |
| Hormone therapy (% ever) | 58.7 | 57.7 | 53.0 | 50.5 | 44.5 |
| Alcohol intake—drink/wk (mean) | 2.3 | 2.0 | 1.8 | 1.4 | 1.0 |
| Physical activity (MET), mean | 15.7 | 11.2 | 10.2 | 7.7 | 6.2 |
| Pack-years of smoking, mean | 8.7 | 9.4 | 8.9 | 8.4 | 9.5 |
| Total energy intake (Kcal/day), mean | 1528 | 1585 | 1632 | 1709 | 1848 |
| Total carbohydrate intake (g/day), mean | 198 | 199 | 201 | 207 | 217 |
| Education (% post-college) | 29.1 | 22.5 | 19.5 | 19.3 | 17.6 |
| Ethnicity, % | |||||
| Non-Hispanic white | 86.6 | 81.4 | 77.6 | 73.9 | 67.9 |
| Black | 7.6 | 10.6 | 13.5 | 15.8 | 22.6 |
| Hispanic | 3.7 | 6.6 | 7.2 | 7.9 | 6.7 |
| Other | 2.1 | 1.4 | 1.7 | 2.4 | 2.8 |