Table 3.
Body Mass Index and Breast Cancer Risk, Multiethnic Cohort, 1993-2010a
| Characteristic | Category | Cases with T2D | Models without T2D | T2D Included | ||
|---|---|---|---|---|---|---|
| HR | 95% CI | HR | 95% CI | |||
| All women | <20 kg/m2 | 18 | 0.94 | 0.85, 1.03 | 0.94 | 0.85, 1.03 |
| ≥20-<25 kg/m2 | 140 | 1.00 | 1.00 | |||
| ≥25-<30 kg/m2 | 314 | 1.22 | 1.15, 1.29 | 1.21 | 1.14, 1.29 | |
| ≥30 kg/m2 | 424 | 1.33 | 1.24, 1.43 | 1.31 | 1.22, 1.41 | |
| Obesity (>30 kg/m2) as compared to 20-<25 kg/m2 | ||||||
| Postmenopausal women | 728 | 1.34 | 1.17, 1.45 | 1.32 | 1.22, 1.43 | |
| Ethnicity | White | 116 | 1.27 | 1.06, 1.66 | 1.33 | 1.15, 1.53 |
| African American | 227 | 1.24 | 1.06, 1.44 | 1.21 | 1.04, 1.41 | |
| Native Hawaiian | 107 | 1.33 | 1.08, 1.65 | 1.35 | 1.09, 1.67 | |
| Japanese American | 239 | 1.43 | 1.22, 1.69 | 1.46 | 1.23, 1.73 | |
| Latina | 207 | 1.22 | 1.04, 1.44 | 1.17 | 0.99, 1.38 | |
| US-born | 130 | 1.36 | 1.10, 1.69 | 1.32 | 1.06, 1.64 | |
| Foreign-born | 77 | 0.98 | 0.76, 1.29 | 0.94 | 0.72, 1.23 | |
| T2D | No | 5,703 | 1.30 | 1.20, 1.41 | NA | |
| Yes | 896 | 1.41 | 1.16, 1.71 | NA | ||
a
Hazard ratios (HR) and 95% confidence intervals (CI) obtained by Cox regression with ethnicity as strata and age as time metric and adjusted for age at cohort entry, education, family history of breast cancer, alcohol intake, physical activity, age at menarche, parity, age at first live birth, postmenopausal hormone use, and ethnicity and T2D depending on the model.