Dataset Information

Similar names, different results: Consistency of the associations between prenatal exposure to phthalates and parent-ratings of behavior problems in preschool children.

ABSTRACT:

Background

Environmental health research has reported mixed findings on the associations between prenatal exposure to phthalates and parent-ratings of child behavioral problems.

Objective

We examined the consistency of the associations between prenatal urinary phthalate concentrations and child behavior scores across two standardized instruments - the Behavior Assessment System for Children-Second Edition (BASC-2) and the Child Behavior Checklist (CBCL) - using two analytical approaches used to correct for urine dilution.

Method

A sample of 351 mother-child pairs were selected from a prospective birth cohort of pregnant women enrolled between 2009 and 2012. Women provided spot urine samples during the second trimester of pregnancy, which were analyzed for levels of nine urinary phthalate metabolites. When their typically developing children were 3-4 years of age, mothers completed the BASC-2 and CBCL on the same day. Adjusted regression analyses examined the associations between maternal prenatal phthalate concentrations and child behavior scores on the BASC-2 and CBCL. To correct for urine dilution, primary regression analyses included urinary creatinine concentration as a separate independent variable (i.e., covariate). In the secondary regression analyses, creatinine-adjusted phthalate concentrations were used.

Results

Primary logistic regression analyses that included urinary creatinine as a covariate showed that higher prenatal phthalate concentrations were related to increased odds of scores falling into the borderline or clinical range on the Hyperactivity, Aggression, Anxiety, Depression, Withdrawal, Externalizing Problems, Internalizing Problems, and Behavioral Symptoms Index scales on the BASC-2 (ORs from 1.39 to 2.07), but only the Anxious/Depressed and Externalizing Problems scales on the CBCL (ORs from 1.80 to 3.28). Primary linear regression analyses showed that higher prenatal phthalate concentrations were related to higher scores on the Externalizing Problems (β's = 0.16), Internalizing Problems (β's from 0.16 to 0.20), and Behavioral Symptoms Index (β's from 0.18 to 0.21) scales on the BASC-2, but not related to any CBCL scales. Sex-stratified analyses found that many associations were only significant for male children. Secondary analyses using creatinine-adjusted phthalate concentrations revealed that some of the associations from the primary analyses remained significant; however, a number of unique associations were observed.

Conclusion

Prenatal phthalate exposure was associated with preschool behavioral development; however, findings were not consistent for the BASC-2 and CBCL, especially related to the clinical/syndrome scales and Internalizing Problems scale. Further, many findings differed based on the analytical approach used to correct for urine dilution. Future work is needed to delineate the similarities and differences between similarly named child behavior constructs assessed by different neurodevelopmental assessments. Also, research is needed to better understand why and how different analytical approaches influence the reported associations between maternal prenatal phthalate concentrations and children's behavior problems.

SUBMITTER: England-Mason G

PROVIDER: S-EPMC7493743 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundPrevious research reports associations between prenatal exposure to phthalates and childhood behavior problems; however, the neural mechanisms that may underlie these associations are relatively unexplored.ObjectiveThis study examined microstructural white matter as a possible mediator of the associations between prenatal phthalate exposure and behavior problems in preschool-aged children.MethodsData are from a subsample of a prospective pregnancy cohort, the Alberta Pregnancy Outcomes and Nutrition (APrON) study (n = 76). Mother-child pairs were included if mothers provided a second trimester urine sample, if the child completed a successful magnetic resonance imaging (MRI) scan at age 3-5 years, and if the Child Behavior Checklist was completed within 6 months of the MRI scan. Molar sums of high (HMWP) and low molecular weight phthalates (LMWP) were calculated from levels in urine samples. Associations between prenatal phthalate concentrations, fractional anisotropy (FA) and mean diffusivity (MD) in 10 major white matter tracts, and preschool behavior problems were investigated.ResultsMaternal prenatal phthalate concentrations were associated with MD of the right inferior fronto-occipital fasciculus (IFO), right pyramidal fibers, left and right uncinate fasciculus (UF), and FA of the left inferior longitudinal fasciculus (ILF). Mediation analyses showed that prenatal exposure to HMWP was indirectly associated with Internalizing (path ab = 0.09, CI.95 = 0.02, 0.20) and Externalizing Problems (path ab = 0.09, CI.95 = 0.01, 0.19) through MD of the right IFO, and to Internalizing Problems (path ab = 0.11, CI.95 = 0.01, 0.23) through MD of the right pyramidal fibers.DiscussionThis study provides the first evidence of childhood neural correlates of prenatal phthalate exposure. Results suggest that prenatal phthalate exposure may be related to microstructural white matter in the IFO, pyramidal fibers, UF, and ILF. Further, MD of the right IFO and pyramidal fibers may transmit childhood risk for behavioral problems.

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