Table 2.
Multivariable relative risks (RRs) of incident endometrial cancer (EC) according to categories of Waist Circumference (WC), Hip Circumference (HC) and Waist to Hip Ratio (WHR) in the Nurses’ Health Study
| Median | Number of cases | Age-adjusted RR* | Multivariable RR1† | Multivariable RR2‡ | ||
|---|---|---|---|---|---|---|
| WC (inch) | ≤27 | 26 | 47 | 1.0 (Ref) | 1.0 (Ref) | 1.0 (Ref) |
| 28-29 | 28 | 47 | 0.82 (0.54-1.23) | 0.83 (0.55-1.25) | 0.75 (0.50-1.13) | |
| 30-32 | 31 | 81 | 0.95 (0.66-1.37) | 0.98 (0.68-1.41) | 0.77 (0.53-1.12) | |
| 33-37 | 35 | 129 | 1.31 (0.93-1.85) | 1.38 (0.97-1.95) | 0.88 (0.61-1.28) | |
| ≥38 | 40 | 145 | 2.30 (1.63-3.24) | 2.44 (1.72-3.45) | 1.08 (0.69-1.67) | |
| p for trend | <0.001 | <0.001 | 0.23 | |||
| HC (inch) | ≤38 | 35 | 49 | 1.0 (Ref) | 1.0 (Ref) | 1.0 (Ref) |
| 37-38 | 38 | 67 | 1.09 (0.75-1.57) | 1.07 (0.74-1.56) | 0.96 (0.66-1.39) | |
| 39-40 | 39 | 86 | 1.39 (0.98- 1.98) | 1.37 (0.96-1.96) | 1.06 (0.73-1.52) | |
| 41-44 | 42 | 136 | 1.71 (1.23-2.38) | 1.69 (1.21- 2.36) | 1.04 (0.73-1.50) | |
| ≥45 | 47 | 111 | 2.82 (2.00-3.97) | 2.85 (2.01-4.02) | 1.06 (0.66-1.69) | |
| p for trend | <0.001 | <0.001 | 0.78 | |||
| WHR | <0.73 | 0.71 | 52 | 1.0 (Ref) | 1.0 (Ref) | 1.0 (Ref) |
| 0.73-<0.77 | 0.75 | 73 | 1.08 (0.75-1.54) | 1.11 (0.77-1.59) | 1.05 (0.73-1.51) | |
| 0.77-<0.81 | 0.79 | 83 | 1.13 (0.79-1.60) | 1.19 (0.83-1.69) | 0.98 (0.69-1.40) | |
| 0.81-<0.88 | 0.84 | 121 | 1.29 (0.92-1.80) | 1.38 (0.98-1.92) | 1.04 (0.74-1.46) | |
| ≥0.88 | 0.93 | 120 | 1.56 (1.11-2.20) | 1.69 (1.20-2.40) | 1.15 (0.81-1.64) | |
| p for trend | 0.002 | <0.001 | 0.37 |
Model was stratified by age in months at start of follow-up and calendar year of the current questionnaire cycle.
Model was stratified by age in months at start of follow up and calendar year of the current questionnaire cycle and was simultaneously adjusted for pack-years of smoking (0, 0.1-20, 20.1-40, >40 pack-years), race (White, Black, others), age at menarche (7-11, 12, 13, 14-18 years), oral contraceptive use (no use, <1, 1-3, 36, >6 years), menopausal status (premenopausal, postmenopausal), postmenopausal hormone use (no use, oral conjugated estrogen, oral estrogen and progesterone, others), and parity (0, 1, 2, 3, >3).
Model was adjusted for variables in multivariable model 1 and BMI (kg/m2, continuous).