Table 2.
Results of testing early postnatal physical health measures as mediators of childhood health outcomes among two contrasts, children with any PTE (pre + post-knowledge) compared to no exposure, and children with longer duration of PTE (post-knowledge only) compared to lesser PTE (none-to-Pre-knowledge).
| ANY PTE vs. No Exposure | |||||||||
| DV | n | Total Effect | Average Direct Effect | Average Indirect Effect | 95 % CI | Proportion Mediated (%) | |||
| LL | UL | ||||||||
| Total Cortical Area | Birthweight | 8,118 | −0.06 (p = 0.05) |
−0.06 (p = 0.05) |
−0.01 | −0.02 | 0.00 | 0.14 | NS (p = 0.17) |
| SGA b | 5,440 | −0.04 (p = 0.33) |
−0.03 (p = 0.43) |
−0.007 | −0.02 | 0.00 | 0.10 | NS (p = 0.38) |
|
| Breastfeeding (months) | 8,158 | −0.13 (p = 0.04) |
−0.05 (p = 0.18) |
−0.01 | −0.01 | 0.00 | <0.001 | NS (p = 0.13) |
|
| Total Cortical Area | Birthweight | 8,118 | −0.06 (p = 0.13) |
−0.06 (p = 0.08) |
−0.01 | −0.01 | 0.00 | <0.001 | NS (p = 0.06) |
| SGA b | 5,440 | −0.04 (p = 0.27) |
−0.12 (p = 0.06) |
−0.01 | −0.01 | 0.00 | 0.08 | NS (p = 0.34) |
|
| Breastfeeding (months) | 8,158 | −0.13 (p = 0.04) |
−0.06 (p = 0.08) |
−0.01 | −0.01 | 0.00 | <0.001 | NS (p = 0.05) |
|
| Cognition a | Birthweight | 5,357 | −0.06 (p = 0.05) |
−1.32 (p = 0.01) |
−0.02 | −0.06 | 0.02 | 0.41 | NS (p = 0.40) |
| SGA b | 3,553 | −1.30 (p = 0.03) |
−1.20 (p = 0.03) |
−0.03 | −0.11 | 0.01 | 0.26 | NS (p = 0.26) |
|
| Breastfeeding (months) | 5,392 | −1.80 (p = 0.14) |
−1.12 (p = 0.01) |
−0.15 | −0.25 | −0.07 | < 0.001 | 11% (p = 0.006) |
|
| Obesity b | Birthweight | 5,851 | 0.01 (p = 0.55) |
0.01 (p = 0.40) |
−0.003 | −0.01 | 0.00 | 0.02 | NS (p = 0.55) |
| SGA b | 5,851 | 0.01 (p = 0.47) |
0.01 (p = 0.40) |
−0.003 | −0.003 | 0.00 | 0.04 | NS (p = 0.50) |
|
| Breastfeeding (months) | 5,880 | 0.01 (p = 0.60) |
0.005 (p = 0.71) |
0.002 | 0.001 | 0.00 | 0.006 | NS (p = 0.60) |
|
| Longer Duration of PTE vs. Lesser Exposure (none-to-Pre-knowledge) | |||||||||
| DV | n | Total Effect | Average Direct Effect | Average Indirect Effect | 95 % CI | Proportion Mediated (%) | |||
| LL | UL | ||||||||
| Total Cortical Area | Birthweight | 8,118 | −0.11 (p = 0.03) |
−0.07 (p = 0.18) |
−0.05 | −0.07 | −0.03 | <0.001 | 39% (p = 0.03) |
| SGA b | 5,440 | −0.13 (p = 0.04) |
−0.11 (p = 0.07) |
−0.01 | −0.03 | 0.00 | 0.03 | NS (p = 0.07) |
|
| Breastfeeding (months) | 8,158 | −0.11 (p = 0.02) |
−0.10 (p = 0.04) |
−0.01 | −0.014 | 0.00 | <0.001 | 7% (p = 0.02) |
|
| Total Volume | Birthweight | 8,118 | −0.10 (p = 0.07) |
−0.05 (p = 0.30) |
−0.04 | −0.07 | −0.02 | <0.001 | NS (p = 0.07) |
| SGA b | 5,440 | −0.13 (p = 0.04) |
−0.12 (p = 0.06) |
−0.01 | −0.03 | 0.00 | 0.04 | NS (p = 0.07) |
|
| Breastfeeding (months) | 8,158 | 0.004 (p < 0.001) |
−0.11 (p < 0.001) |
−0.01 | −0.012 | −0.01 | <0.001 | 8% (p < 0.001) |
|
| Cognition a | Birthweight | 5,357 | −1.95 (p = 0.032) |
−1.86 (p = 0.01) |
−0.09 | −0.20 | −0.01 | 0.01 | 4% (p = 0.03) |
| SGA b | 3,553 | −1.80 (p = 0.14) |
−1.70 (p = 0.16) |
−0.07 | −0.26 | 0.02 | 0.19 | NS (p = 0.31) |
|
| Breastfeeding (months) | 5,392 | −2.15 (p = 0.02) |
−1.98 (p = 0.02) |
−0.17 | −0.33 | −0.03 | 0.02 | 8% (p = 0.04) |
|
| Obesity b | Birthweight | 5,851 | 0.06 (p = 0.001) |
0.08 (p =0.004) |
−0.01 | −0.02 | −0.01 | < 0.001 | −18% (p = 0.01) |
| SGA b | 5,851 | 0.06 (p = 0.01) |
0.07 (p = 0.01) |
−0.003 | −0.01 | 0.00 | 0.008 | −5% (p = 0.02) |
|
| Breastfeeding (months) | 5,880 | 0.004 (p = 0.01) |
0.05 (p = 0.036) |
0.004 | 0.001 | 0.00 | 0.008 | 7% (p = 0.036) |
|
a
Models tested in high SES sample due to SES X PTE interaction.
b
Models include only singletons (no siblings) to allow for logistic model convergence. SGA: small for gestational age; CI: confidence interval; LL: lower limit; UL: upper limit; NS: non-significant.