TABLE 3.
Incidence Rates per 1000 Person-Years and Rate Ratios for Uterine Leiomyomata Confirmed by Hysterectomy According to Measures of Body Size and Body Fat Distribution
| Anthropometric Variable | No. of Cases | Person-Years | Crude IR | Multivariate IRR (95% CI)* |
|---|---|---|---|---|
| BMI, current (kg/m2) | ||||
| <20.0 | 3 | 4033 | 0.7 | 1.00† |
| 20.0–22.4 | 22 | 10,297 | 2.1 | 2.22 (0.66–7.45) |
| 22.5–24.9 | 44 | 13,297 | 3.3 | 2.90 (0.90–9.37) |
| 25.0–27.4 | 54 | 12,606 | 4.3 | 3.20 (1.00–10.29) |
| 27.5–29.9 | 42 | 8085 | 5.2 | 3.73 (1.15–12.09) |
| 30.0–32.4 | 37 | 6778 | 5.5 | 3.73 (1.14–12.17) |
| 32.5+ | 59 | 15,250 | 3.9 | 2.67 (0.83–8.57) |
| BMI at age 18 (kg/m2) | ||||
| <18.5 | 52 | 12,500 | 4.2 | 1.00† |
| 18.5–19.9 | 54 | 13,877 | 3.9 | 1.02 (0.69–1.49) |
| 20.0–22.4 | 87 | 21,104 | 4.1 | 1.13 (0.79–1.60) |
| 22.5–24.9 | 41 | 10,899 | 3.8 | 1.08 (0.71–1.64) |
| 25.0–27.4 | 15 | 5884 | 2.6 | 0.75 (0.42–1.34) |
| 27.5–29.9 | 6 | 2469 | 2.4 | 0.76 (0.32–1.78) |
| 30.0+ | 6 | 3613 | 1.7 | 0.58 (0.24–1.35) |
| Weight gain since age 18 (kg) | ||||
| <5 | 19 | 12,900 | 1.5 | 1.00† |
| 5–9 | 21 | 10,994 | 1.9 | 1.06 (0.57–1.97) |
| 10–14 | 48 | 12,021 | 4.0 | 1.93 (1.13–3.31) |
| 15–24 | 83 | 18,016 | 4.6 | 1.79 (1.08–2.97) |
| 25+ | 90 | 16,414 | 5.5 | 1.84 (1.11–3.05) |
| Height (feet and inches) | ||||
| ≤5′2″ | 47 | 12,709 | 3.7 | 1.00† |
| 5′3″–5′4″ | 60 | 17,721 | 3.4 | 0.95 (0.65–1.40) |
| 5′5″–5′6″ | 78 | 18,872 | 4.1 | 1.19 (0.83–1.71) |
| 5′7″–5′8″ | 53 | 13,397 | 4.0 | 1.26 (0.85–1.87) |
| 5′9″+ | 23 | 7647 | 3.0 | 1.07 (0.64–1.77) |
| Waist circumference (inches)‡ | ||||
| < 27 | 27 | 10,317 | 2.6 | 1.00† |
| 27–29 | 37 | 14,146 | 2.6 | 0.73 (0.44–1.21) |
| 30–32 | 64 | 12,951 | 4.9 | 1.02 (0.62–1.67) |
| 33–35 | 38 | 8,182 | 4.6 | 0.85 (0.48–1.49) |
| 36+ | 54 | 12,938 | 4.2 | 0.74 (0.41–1.34) |
| Hip circumference (inches)‡ | ||||
| <36 | 23 | 10,226 | 2.2 | 1.00† |
| 36–37 | 29 | 10,198 | 2.8 | 1.05 (0.60–1.83) |
| 38–40 | 66 | 14,869 | 4.4 | 1.21 (0.73–1.99) |
| 41–44 | 62 | 12,779 | 4.8 | 1.15 (0.67–1.98) |
| 45+ | 40 | 10,463 | 3.8 | 0.92 (0.50–1.71) |
| Waist-to-hip ratio‡ | ||||
| <0.71 | 39 | 11,838 | 3.3 | 1.00† |
| 0.71–0.75 | 38 | 11,611 | 3.3 | 0.97 (0.62–1.51) |
| 0.76–0.79 | 50 | 11,993 | 4.2 | 1.09 (0.71–1.66) |
| 0.80–0.85 | 53 | 11,521 | 4.6 | 1.17 (0.77–1.78) |
| 0.86+ | 40 | 11,571 | 3.5 | 0.83 (0.52–1.31) |
Adjusted for age (1-yr intervals), time period (1997–1999 vs. 1999–2001), age at menarche (years), parity (number of births), age at first birth (years), years since last birth (linear term + 2 spline terms), ever use of oral contraceptives, education (≤12, 13–15, 16, 17+), living in the West, current alcohol consumption (<1, 1–6, 7+ per week), and smoking (never, former, current). Models of waist, hip, and waist-to-hip ratio measures are further adjusted for BMI in 1995 (<20, 20–24, 25–29, 30+).
Reference category.
Limited to 17,876 women with complete data on waist and hip circumference in 1995.