Table 3.
Associations between pregnancy exposures and change in behavioral problems, showing exposures selected into the multiple-exposure modelsa (out of 88 candidate exposures, N = 1287).
|
Internalizing scale |
Externalizing scale |
ADHD index |
|||||
|---|---|---|---|---|---|---|---|
| Exposure (IQR or reference category) | Exposure family | aMR [95%CI]b | p-value | aMR [95%CI]b | p-value | aMR [95%CI]b | p-value |
| Traffic density on nearest road (3598 vehicles/day) | Road traffic | 1.07 [1.00; 1.14] | 0.050 | 1.10 [1.03; 1.17] | 0.004 | ||
| Green spaces (300 m) | Natural spaces | 1.15 [1.01; 1.31] | 0.034 | ||||
| Meat intake | Lifestyle/Diet | ||||||
| Medium (vs. low) | 0.96 [0.84; 1.10] | 0.578 | 1.02 [0.87; 1.20] | 0.808 | |||
| High (vs. low) | 1.11 [0.97; 1.27] | 0.131 | 1.16 [0.99; 1.36] | 0.060 | |||
| Fish and seafood | Lifestyle/Diet | ||||||
| Medium (vs. low) | 1.15 [0.99; 1.33] | 0.064 | |||||
| High (vs. low) | 1.12 [0.95; 1.32] | 0.191 | |||||
| Fastfood intake | Lifestyle/Diet | ||||||
| Medium (vs. low) | 0.84 [0.67; 1.04] | 0.113 | |||||
| High (vs. low) | 0.93 [0.75; 1.14] | 0.467 | |||||
| Moderate physical activity, t3 | Lifestyle/Physical activity | ||||||
| Often (vs. none or sometimes) | 1.10 [0.94; 1.29] | 0.244 | 1.09 [0.91; 1.29] | 0.347 | |||
| Very often (vs. none or sometimes) | 0.91 [0.78; 1.07] | 0.253 | 0.93 [0.78; 1.11] | 0.406 | |||
| Smoking in pregnancy | Tobacco smoking | ||||||
| Second-hand smoking (vs. none) | 1.28 [1.12; 1.45] | <0.001 | 1.25 [1.09; 1.44] | 0.002 | |||
| Active smoking (vs. none) | 1.20 [1.03; 1.39] | 0.020 | 1.31 [1.09; 1.59] | 0.005 | |||
| Cotinine (µg/L) | Tobacco smoking | ||||||
| 18.4–50 (vs. < 18.4) | 1.05 [0.96; 1.15] | 0.262 | |||||
| >50 (vs. < 18.4) | |||||||
| Bisphenol-A (4.96 µg/g) | Phenol | 1.06 [0.98; 1.15] | 0.152 | ||||
| Caesium (0.97 µg/L) | Metal | 0.94 [0.83; 1.06] | 0.281 | ||||
| Dimethyl phosphate (11.37 µg/g) | Organophosphate pesticides | 1.07 [1.00; 1.15] | 0.067 | ||||
| Perfluorooctanoate (1.96 µg/L) | Perfluoroalkyl substances (PFAS) | 0.95 [0.86; 1.05] | 0.301 | ||||
| Perfluoroundecanoate (0.18 µg/L) | Perfluoroalkyl substances (PFAS) | 0.93 [0.84; 1.03] | 0.162 | ||||
The selection of exposures was determined by the least absolute shrinkage and selection operator (LASSO) algorithm applying log link function.
The change in behavioral problems was modelled with negative binomial regression which model the ratio of the mean score for one unit change in the exposure (the coefficients obtained needed to be exponentiated). The results are presented as adjusted mean ratios (aMR) with corresponding 95% confidence intervals (CIs). In all of these models, the exposure estimate was reported for one interquartile range (IQR) increase in exposure levels—for example, a ratio of mean score of 1.25 for an IQR increase in the exposure meant that those with an exposure at the 75th percentile had a 25% higher mean score, compared with those with an exposure at the 25th percentile. These coefficients are adjusted for the other exposures and for cohort, maternal age, maternal education level, maternal pre-pregnancy body mass index, parity, parental country of birth, child age, child sex, and child height. Abbreviations: CI = confidence interval; IQR, interquartile range; cat., categories.