Table 4.
Conditional logistic regression models to estimate the association between quintiles of PBDEs and PBB-153 plasma levels expressed in ng/L and breast cancer risk: adjusted odds ratios (ORs) and 95% confidence intervals (CIs) (E3N cohort, N = 394)
| ng/L plasma | Model 0 | P trend | Model 1 | P trend | Model 2 | P trend | ||
|---|---|---|---|---|---|---|---|---|
| Number (%) controls |
Number (%) cases | OR [95% CI] | OR [95% CI] | OR [95% CI] | ||||
| PBDE sum | 197 | 197 | ||||||
| Q1 | 39(19.80) | 37(18.78) | Reference | 0.97 | Reference | 0.66 | Reference | 0.59 |
| Q2 | 39(19.80) | 36(18.27) | 0.99 [0.53; 1.84] | 1.09 [0.52; 2.26] | 1.14 [0.54; 2.41] | |||
| Q3 | 40(20.30) | 38(19.29) | 1.01 [0.56; 1.82] | 1.00 [0.51; 1.94] | 1.02 [0.52; 2.00] | |||
| Q4 | 39(19.80) | 44 (22.34) | 1.18 [0.64; 2.18] | 1.20 [0.59; 2.44] | 1.20 [0.59; 2.46] | |||
| Q5 | 40(20.30) | 42 (21.32) | 1.10 [0.58; 2.08] | 1.13 [0.54; 2.39] | 1.21 [0.57; 2.58] | |||
| log-PBDE sum | 0.98 [0.67; 1.42] | 0.9 | 0.95 [0.62; 1.46] | 0.83 | 0.97 [0.63; 1.50] | 0.88 | ||
| BDE-28 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 34 (17.26) | Reference | 0.32 | Reference | 0.47 | Reference | 0.54 |
| Q2 | 39(19.80) | 40 (20.30) | 1.16 [0.62–2.18] | 1.39 [0.67–2.90] | 1.36 [0.65–2.85] | |||
| Q3 | 40(20.30) | 34 (17.26) | 0.99 [0.51–1.91] | 0.92 [0.43–1.97] | 0.99 [0.46–2.14] | |||
| Q4 | 39(19.80) | 41 (20.81) | 1.18 [0.62–2.26] | 1.29 [0.61–2.72] | 1.32 [0.63–2.80] | |||
| Q5 | 40(20.30) | 48 (24.37) | 1.36 [0.72–2.53] | 1.33 [0.65–2.70] | 1.27 [0.62–2.60] | |||
| log-BDE-28 | 1.04 [0.80; 1.37] | 0.75 | 1.00 [0.74; 1.35] | 0.98 | 0.97 [0.72; 1.33] | 0.87 | ||
| BDE-47 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 41 (20.81) | Reference | 0.72 | Reference | 0.81 | Reference | 0.72 |
| Q2 | 39(19.80) | 34 (17.26) | 0.82 [0.43–1.56] | 0.71 [0.35–1.47] | 0.73 [0.35–1.53] | |||
| Q3 | 40(20.30) | 38 (19.29) | 0.91 [0.50–1.67] | 0.98 [0.49–1.95] | 1.01 [0.50–2.05] | |||
| Q4 | 39(19.80) | 40 (20.30) | 0.97 [0.53–1.79] | 0.84 [0.42–1.67] | 0.83 [0.41–1.69] | |||
| Q5 | 40(20.30) | 44 (22.34) | 1.06 [0.57–1.95] | 1.05 [0.52–2.11] | 1.11 [0.54–2.26] | |||
| log-BDE-47 | 0.94 [0.70; 1.25] | 0.66 | 0.92 [0.66; 1.29] | 0.64 | 0.94 [0.67; 1.32] | 0.72 | ||
| BDE-99 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 31 (15.74) | Reference | 0.55 | Reference | 0.66 | Reference | 0.66 |
| Q2 | 39(19.80) | 45 (22.84) | 1.50 [0.77–2.90] | 1.30 [0.62–2.73] | 1.23 [0.57–2.62] | |||
| Q3 | 40(20.30) | 38 (19.29) | 1.27 [0.64–2.50] | 1.26 [0.59–2.71] | 1.32 [0.60–2.90] | |||
| Q4 | 39(19.80) | 41 (20.81) | 1.38 [0.70–2.72] | 1.20 [0.56–2.56] | 1.09 [0.50–2.38] | |||
| Q5 | 40(20.30) | 42 (21.32) | 1.36 [0.69–2.66] | 1.28 [0.59–2.75] | 1.29 [0.59–2.83] | |||
| log-BDE-99 | 1.04 [0.78; 1.39] | 0.79 | 1.06 [0.76; 1.48] | 0.72 | 1.07 [0.77; 1.49] | 0.69 | ||
| BDE-100 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 49 (24.87) | Reference | 0.53 | Reference | 0.41 | Reference | 0.46 |
| Q2 | 39(19.80) | 36 (18.27) | 0.71 [0.38–1.33] | 0.56 [0.27–1.17] | 0.59 [0.28–1.27] | |||
| Q3 | 40(20.30) | 29 (14.72) | 0.54 [0.28–1.05] | 0.42 [0.19–0.92] | 0.42 [0.19–0.93] | |||
| Q4 | 39(19.80) | 46 (23.35) | 0.93 [0.51–1.70] | 0.91 [0.46–1.80] | 0.87 [0.44–1.74] | |||
| Q5 | 40(20.30) | 37 (18.78) | 0.68 [0.35–1.30] | 0.53 [0.24–1.17] | 0.58 [0.26–1.28] | |||
| Log-BDE100 | 0.89 [0.65; 1.20] | 0.44 | 0.95 [0.53; 1.70] | 0.85 | 0.97 [0.54; 1.75] | 0.91 | ||
| BDE-153 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 43 (21.83) | Reference | 0.92 | Reference | 0.73 | Reference | 0.78 |
| Q2 | 39(19.80) | 45 (22.84) | 1.08 [0.58–2.01] | 1.30 [0.63–2.68] | 1.28 [0.62–2.67] | |||
| Q3 | 40(20.30) | 22 (11.17) | 0.52 [0.26–1.01] | 0.40 [0.17–0.90] | 0.42 [0.18–0.98] | |||
| Q4 | 39(19.80) | 44 (22.34) | 1.02 [0.56–1.87] | 1.10 [0.55–2.22] | 1.12 [0.55–2.29] | |||
| Q5 | 40(20.30) | 43 (21.83) | 0.96 [0.52–1.76] | 0.85 [0.42–1.74] | 0.87 [0.43–1.79] | |||
| log-BDE-153 | 1.02 [0.62; 1.68] | 0.94 | 0.95 [0.53; 1.70] | 0.85 | 0.97 [0.54; 1.75] | 0.91 | ||
| BDE-154 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 35 (17.77) | Reference | 0.47 | Reference | 0.86 | Reference | 0.86 |
| Q2 | 39(19.80) | 38 (19.29) | 1.09 [0.56–2.11] | 0.93 [0.44–1.97] | 0.91 [0.43–1.96] | |||
| Q3 | 40(20.30) | 38 (19.29) | 1.08 [0.57–2.07] | 1.04 [0.50–2.15] | 1.06 [0.51–2.21] | |||
| Q4 | 39(19.80) | 43 (21.83) | 1.26 [0.66–2.43] | 1.14 [0.54–2.41] | 1.13 [0.53–2.40] | |||
| Q5 | 40(20.30) | 43 (21.83) | 1.24 [0.64–2.40] | 1.00 [0.47–2.13] | 1.00 [0.46–2.15] | |||
| log-BDE-154 | 0.99 [0.75; 1.31] | 0.95 | 0.97 [0.70; 1.33] | 0.83 | 0.96 [0.70; 1.33] | 0.82 | ||
| PBB-153 | 197 | 197 | ||||||
| Q1 | 39(19.80) | 47 (23.86) | Reference | 0.31 | Reference | 0.33 | Reference | 0.29 |
| Q2 | 39(19.80) | 41 (20.81) | 0.90 [0.50–1.61] | 0.73 [0.38–1.41] | 0.67 [0.34–1.31] | |||
| Q3 | 40(20.30) | 29 (14.72) | 0.58 [0.31–1.11] | 0.49 [0.23–1.07] | 0.48 [0.22–1.06] | |||
| Q4 | 39(19.80) | 51 (25.89) | 1.06 [0.57–1.97] | 0.96 [0.47–1.96] | 0.92 [0.45–1.90] | |||
| Q5 | 40(20.30) | 29 (14.72) | 0.58 [0.29–1.13] | 0.53 [0.24–1.17] | 0.50 [0.22–1.13] | |||
| log-PBB-153 | 1.02 [0.62; 1.68] | 0.94 | 0.95 [0.53; 1.70] | 0.85 | 0.97 [0.54; 1.75] | 0.91 |
Model 0: crude estimates;
Model 1: adjusted for total plasma lipid content (ng/L, continuous), smoking status (never vs. ever), physical activity measured in metabolic equivalent tasks (MET)-hour/week (< 35 vs. ≥35), education (≤ 12 years, 12 to 14 years, > 14 years), personal history of benign breast disease (no vs. yes), and family history of breast cancer (none, in first-degree relatives, in extended relatives), parity and age at first full-term pregnancy (FFTP) (no children, 1 or 2 children and < 30 years old at FFTP, ≥3 children and < 30 years old at FFTP, ≥ 30 years old at FFTP), total breastfeeding duration (never, ≤6 or > 6 months), age at menarche (< 13 years vs. ≥ 13 years), current use of menopausal hormone therapy (pre-menopausal, yes, no), and use of oral contraceptives (ever vs. never), menopausal status and age at menopause (pre-menopausal, menopause before age 51, menopause at age 51 or later);
Model 2: Model 1 + adherence score to the Healthy and the Western dietary patterns (above vs. below the median)