Table 2.
Odds ratios (OR) and 95% confidence interval (CI) for associations between anthropometric measures at inclusion (continuous and tertiles) and risk of breast cancer, overall.
| Cases/controls | Model 1 - matcheda | Model 2 - fully adjustedb | Model 3 - residualsc | |
|---|---|---|---|---|
| OR (95% CI) | OR (95% CI) | OR (95% CI) | ||
| Height (m) | ||||
| Continuous, per 10 cm | 403/403 | 1.27 (1.01–1.59) | 1.00 (0.75–1.34) | |
| <1.54 | 116/138 | 1.00 (ref.) | 1.00 (ref.) | |
| 1.54–1.59 | 126/130 | 1.18 (0.83–1.67) | 1.05 (0.67–1.63) | |
| ≥1.60 | 161/135 | 1.47 (1.03–2.10) | 1.11 (0.71–1.73) | |
| P-trend | 0.03 | 0.66 | ||
| Weight (kg) | ||||
| Continuous, per 10 kg | 405/405 | 0.79 (0.71–0.87) | 0.73 (0.63–0.85) | |
| <63.9 | 186/135 | 1.00 (ref.) | 1.00 (ref.) | |
| 63.9–75.8 | 137/132 | 0.77 (0.55–1.07) | 0.59 (0.37–0.94) | |
| ≥75.9 | 82/138 | 0.45 (0.31–0.64) | 0.33 (0.20–0.54) | |
| P-trend | <0.01 | <0.01 | ||
| Waist circumference (cm) | ||||
| Continuous, per 10 cm | 400/400 | 0.83 (0.73–0.93) | 0.81 (0.69–0.96) | 1.38 (0.98–1.94) |
| <86 | 149/132 | 1.00 (ref.) | 1.00 (ref.) | |
| 86–98.9 | 155/136 | 0.97 (0.69–1.36) | 1.09 (0.69–1.71) | |
| ≥99 | 96/132 | 0.59 (0.40–0.87) | 0.66 (0.40–1.09) | |
| P-trend | 0.01 | 0.12 | ||
| Hip circumference (cm) | ||||
| Continuous, per 10 cm | 401/401 | 0.82 (0.72–0.93) | 0.80 (0.67–0.95) | 1.66 (1.13–2.45) |
| <100 | 147/132 | 1.00 (ref.) | 1.00 (ref.) | |
| 100–108.7 | 157/135 | 1.05 (0.74–1.49) | 1.15 (0.73–1.82) | |
| ≥109 | 97/134 | 0.64 (0.45–0.92) | 0.68 (0.42–1.10) | |
| P-trend | 0.01 | 0.09 | ||
| BMI (kg/m2) | ||||
| Continuous, per 1 unit | 403/403 | 0.92 (0.90–0.95) | 0.93 (0.89–0.96) | 0.92 (0.89–0.96) |
| <25.6 | 191/134 | 1.00 (ref.) | 1.00 (ref.) | |
| 25.6–30.1 | 140/136 | 0.71 (0.51–0.98) | 0.66 (0.43–1.01) | |
| ≥30.2 | 72/133 | 0.36 (0.25–0.53) | 0.36 (0.22–0.59) | |
| P-trend | <0.01 | <0.01 | ||
| Waist-to-hip ratio | ||||
| Continuous, per 0.1 unit | 400/400 | 0.90 (0.72–1.13) | 0.90 (0.68–1.20) | |
| <0.84 | 141/133 | 1.00 (ref.) | 1.00 (ref.) | |
| 0.84–0.90 | 124/133 | 0.86 (0.60–1.25) | 0.88 (0.55–1.41) | |
| ≥0.91 | 135/134 | 0.92 (0.61–1.40) | 0.99 (0.58–1.70) | |
| P-trend | 0.65 | 0.91 | ||
| Combined BMI and WCe | ||||
| Normal weight/Normal WC | 116/90 | 1.00 (ref.) | 1.00 (ref.) | |
| Normal weight/High WC | 45/12 | 2.84 (1.44–5.61) | 3.60 (1.47–8.79) | |
| Overweight/Normal WC | 46/52 | 0.68 (0.41–1.13) | 0.65 (0.34–1.27) | |
| Overweight/High WC | 105/93 | 0.89 (0.58–1.37) | 1.02 (0.59–1.77) | |
Abbreviations: BMI, body mass index; CI, confidence interval; OR, odds ratio.
aOdds ratios were estimated by logistic regression conditioned on age (±3 years), city district of residence, and health insurance institution.
bAdditionally adjusted for education (≤primary/secondary/>secondary), history of benign breast disease (yes/no), family history of breast cancer (yes/no), total physical activity (tertiles), number of full-term pregnancies (0/1/≥2), age at first full-term pregnancy (tertiles/nulliparous/missing), cumulated duration of breastfeeding (</≥12 months), age at menarche (</≥12 years old), smoking status (current/former/never), diabetes (yes/no), daily alcohol intake (tertiles/non-consumer). Except for height and leg length, models were additionally adjusted for height (tertiles), thus only women with available information on height were included in the analyses for model 2.
cIn model 3, BMI, residuals of waist circumference regressed on BMI and residuals of hip circumference regressed on BMI were included simultaneously, in addition to adjustment variables of model 2.
dFor test of linear trend across tertiles, participants were assigned the median value in each tertile and the corresponding variable was modelled as a continuous term.
eOnly women with a BMI ≥ 18.5 kg/m2 were included in this analysis. BMI was categorized as normal weight (18.5–24.9), overweight (25–29.9) and obese (≥30) and WC was categorized as normal (≤88 cm) and high (>88 cm).