Table 3.
Crude rates per 1000 person years, 8-year cumulative risk, crude and adjusted* hazard ratios for breast cancer in relation to BMI
| Persons | Cases | Person years | Crude rate per 1000 person years (95% CI) | 8-year cumulative risk (95% CI) | Crude HR (95% CI) | Adjusted HR (95% CI) | |
|---|---|---|---|---|---|---|---|
| BMI | |||||||
| < 18.5 | 320 | 5 | 2260 | 2.21 (0.72–5.16) | 1.56% (0.59%-3.43%) | 0.76 (0.31–1.83) | 0.72 (0.30–1.74) |
| ≥ 18.5– < 25 | 16 233 | 346 | 119 000 | 2.91 (2.61–3.24) | 2.23% (1.99%-2.48%) | 1 (reference) | 1 (reference) |
| ≥ 25– < 30 | 10 809 | 275 | 78 800 | 3.49 (3.09–3.93) | 2.61% (2.31%-2.93%) | 1.20 (1.02–1.40) | 1.19 (1.01–1.40) |
| ≥ 30 | 4148 | 100 | 30 000 | 3.33 (2.71–4.05) | 2.48% (2.03%-3.00%) | 1.14 (0.91–1.43) | 1.19 (0.94–1.50) |
*Adjusted for reproductive factors (age at menarche, use of HRT and oral contraceptives, age at first child birth, number of births, co-medications (insulin, metformin, and statins), heredity, and life-style factors (smoking and alcohol)