TABLE 3.
Associations between prenatal PCB and DDE exposure in quartiles and BMI in children 5 and 7 y of age and the change in BMI from 5 to 7 y of age according to maternal prepregnancy BMI, Faroese Cohort 1996–20011
| Girls (regression coefficient) |
Boys (regression coefficient) |
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| Normal-weight mothers |
Overweight mothers |
Normal-weight mothers |
Overweight mothers |
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| PCBs and DDE in quartiles | Estimate (95% CI) | P | Estimate (95% CI) | P | Estimate (95% CI) | P | Estimate (95% CI) | P |
| BMI 5 y of age [n = 561 (girls: n = 271; overweight mothers: n = 89) (boys: n = 290; overweight mothers: n = 98)] | ||||||||
| PCBs | ||||||||
| Second quartile (0.75–1.18 μg/g lipid) | 0.10 (−0.53, 0.74) | 0.95 | 0.19 (−0.81, 1.20) | 0.76 | 0.39 (−0.10, 0.89) | 0.23 | −0.60 (−1.47, 0.27) | 0.18 |
| Third quartile (1.19–1.95 μg/g lipid) | 0.10 (−0.52, 0.72) | 0.79 | 0.13 (−1.06, 1.32) | 0.64 | 0.40 (−0.12, 0.92) | 0.13 | 0.12 (−0.72, 0.96) | 0.70 |
| Fourth quartile (>1.95 μg/g lipid) | −0.12 (−0.82, 0.58) | 0.33 | 0.59 (−0.47, 1.65) | 0.31 | −0.01 (−0.53, 0.51) | 0.74 | 0.01 (−0.84, 0.87) | 0.92 |
| Continuous | −0.10 (−0.43, 0.22) | 0.23 | 0.32 (−0.26, 0.89) | 0.35 | −0.08 (−0.35, 0.20) | 0.53 | −0.06 (−0.46, 0.33) | 0.78 |
| DDE | ||||||||
| Second quartile (0.34–0.56 μg/g lipid) | 0.48 (−0.13, 1.09) | 0.18 | −0.66 (−1.65, 0.34) | 0.16 | 0.40 (−0.09, 0.89) | 0.09 | −0.54 (−1.45, 0.37) | 0.35 |
| Third quartile (0.57–0.92 μg/g lipid) | 0.40 (−0.18, 0.97) | 0.41 | −0.27 (−1.51, 0.98) | 0.70 | 0.16 (−0.33, 0.64) | 0.45 | −0.03 (−0.89, 0.83) | 0.89 |
| Fourth quartile (>0.92 μg/g lipid) | −0.18 (−0.82, 0.45) | 0.29 | 0.15 (−0.90, 1.20) | 0.67 | −0.25 (−0.77, 0.27) | 0.41 | 0.33 (−0.51, 1.16) | 0.42 |
| Continuous | 0.01 (−0.28, 0.30) | 0.67 | 0.10 (−0.34, 0.55) | 0.64 | −0.12 (−0.34, 0.11) | 0.39 | −0.06 (−0.27, 0.39) | 0.76 |
| BMI at 7 y of age [n = 539 (girls: n = 259; overweight mothers: n = 87) (boys: n = 280; overweight mothers: n = 92)] | ||||||||
| PCBs | ||||||||
| Second quartile (0.75–1.18 μg/g lipid) | 0.33 (−0.55, 1.20) | 0.46 | 0.76 (−0.63, 2.15) | 0.28 | 0.51 (−0.15, 1.18) | 0.14 | −0.79 (−1.86, 0.28) | 0.15 |
| Third quartile (1.19–1.95 μg/g lipid) | 0.14 (−0.71, 0.99) | 0.75 | 0.66 (−0.98, 2.29) | 0.43 | 0.11 (−0.58, 0.81) | 0.73 | 0.26 (−0.78, 1.30) | 0.62 |
| Fourth quartile (>1.95 μg/g lipid) | 0.04 (−0.93, 1.01) | 0.93 | 2.07 (0.59, 3.55) | 0.007 | −0.33 (−1.03, 0.36) | 0.42 | 0.04 (−1.02, 1.11) | 0.94 |
| Continuous | −0.04 (−0.49, 0.40) | 0.85 | 1.13 (0.33, 1.93) | 0.006 | −0.28 (−0.64, 0.08) | 0.16 | −0.15 (−0.64, 0.34) | 0.54 |
| DDE | ||||||||
| Second quartile (0.34–0.56 μg/g lipid) | 0.30 (−0.56, 1.15) | 0.49 | −0.06 (−1.49, 1.38) | 0.94 | 0.47 (−0.11, 1.21) | 0.13 | −1.21 (−2.34, 0.09) | 0.17 |
| Third quartile (0.57–0.92 μg/g lipid) | 0.45 (−0.36, 1.26) | 0.28 | −0.09 (−1.91, 1.74) | 0.92 | −0.09 (−0.74, 0.57) | 0.65 | −0.04 (−1.13, 1.05) | 0.95 |
| Fourth quartile (>0.92 μg/g lipid) | −0.18 (−1.08, 0.71) | 0.69 | 1.29 (−0.24, 2.81) | 0.10 | −0.37 (−1.09, 0.34) | 0.21 | −0.24 (−1.31, 0.83) | 0.66 |
| Continuous | 0.05 (−0.35, 0.46) | 0.80 | 0.61 (−0.03, 1.24) | 0.06 | −0.23 (−0.54, 0.07) | 0.09 | −0.12 (−0.55, 0.30) | 0.56 |
| Change in BMI from 5 to 7 y of age [n = 515 (girls: n = 250; overweight mothers: n = 83) (boys: n = 265; overweight mothers: n = 89)] | ||||||||
| PCBs | ||||||||
| Second quartile (0.75–1.18 μg/g lipid) | 0.21 (−0.27, 0.70) | 0.39 | 0.28 (−0.49, 1.04) | 0.47 | 0.34 (−0.09, 0.77) | 0.12 | −0.28 (−0.93, 0.38) | 0.40 |
| Third quartile (1.19–1.95 μg/g lipid) | 0.09 (−0.39, 0.57) | 0.71 | 0.56 (−0.34, 1.46) | 0.22 | 0.01 (−0.46, 0.45) | 0.95 | −0.01 (−0.64, 0.64) | 0.99 |
| Fourth quartile (>1.95 μg/g lipid) | 0.17 (−0.37, 0.71) | 0.53 | 1.23 (0.42, 2.05) | 0.003 | −0.05 (−0.50, 0.39) | 0.98 | −0.06 (−0.70, 0.59) | 0.87 |
| Continuous | 0.06 (−0.19, 0.31) | 0.62 | 0.70 (0.26, 1.14) | 0.002 | −0.08 (−0.32, 0.15) | 0.63 | −0.12 (−0.41, 0.16) | 0.40 |
| DDE | ||||||||
| Second quartile (0.34–0.56 μg/g lipid) | −0.27 (−0.59, 0.06) | 0.11 | 0.51 (−0.26, 1.29) | 0.19 | 0.32 (−0.11, 0.75) | 0.26 | −0.51 (−1.19, 0.18) | 0.15 |
| Third quartile (0.57–0.92 μg/g lipid) | −0.06 (−0.37, 0.25) | 0.70 | 0.14 (0.82, 1.10) | 0.77 | −0.04 (−0.46, 0.38) | 0.65 | 0.10 (−0.54, 0.74) | 0.75 |
| Fourth quartile (>0.92 μg/g lipid) | 0.09 (−0.25, 0.43) | 0.61 | 1.11 (0.30, 1.92) | 0.008 | 0.15 (−0.30, 0.61) | 0.70 | −0.40 (−1.03, 0.23) | 0.21 |
| Continuous | 0.05 (−0.11, 0.20) | 0.57 | 0.46 (0.12, 0.80) | 0.008 | −0.04 (−0.23, 0.16) | 0.63 | −1.13 (−0.38, 0.12) | 0.31 |
PCB and DDE concentrations (in μg/g lipid) were measured in maternal serum and log transformed. The PCB concentration was based on the sum of PCB congeners 138, 153, and 180. Sex interactions between PCB and DDE concentrations and BMI at 7 y of age and the change in BMI from 5 to 7 y of age were significant at P < 0.10. Maternal normal weight was defined as maternal prepregnancy BMI (in kg/m2) <25, and maternal overweight was defined as maternal prepregnancy BMI ≥25. Interactions with maternal prepregnancy BMI between the PCB concentration and BMI at 7 y of age, the change in BMI from 5 to 7 y of age, and between the DDE concentration and change in BMI from 5 to 7 y of age were significant at P < 0.10. Regression coefficients were derived by using a multiple linear regression model adjusted for parity (pregnancies before the current one) and maternal age. Continuous estimated coefficients are the absolute change in BMI expected when the log-transformed PCB variable was multiplied by 10. DDE, p,p′-dichlorodiphenyldichloroethylene; PCB, polychlorinated biphenyl.