Polybrominated Diphenyl Ether Exposure In Utero May Increase Anxiety Risk

Gestational serum polybrominated diphenyl ether (PBDE) concentrations may be a marker for anxiety risk in early adolescence, according to study results published in Depression & Anxiety.

Researchers sourced data from the Health Outcomes and Measures of the Environment (HOME) study, which was an ongoing prospective pregnancy and birth study. Pregnant women (N=468) were recruited between 2003 and 2006 at 9 prenatal clinics in Ohio at 16±3 weeks gestation. The outcome of interest for this study was Screen for Child Anxiety Related Emotional Disorders (SCARED) scores at age 12 years among the resulting 236 children on the basis of maternal PBDE concentrations.

The children’s mean age was 12.4 (SD, 0.7) years at the time of the study. A total of 55.9% of the participants were girls, their mothers had given birth at age 29.3 (SD, 5.7) years, 30.8% were college graduates, and the median household income was $55,000 (interquartile range [IQR], $27,500-$85,000).

Most PBDE congeners were detected in maternal serum (87%-99.2%). The most abundant congener was PBDE-47 (geometric mean concentration [GMC], 20.8 ng/g lipid).

At follow-up, the study participants had an average SCARED score of 21.1 (SD, 12.5) points. In general, SCARED scores were higher among girls than boys (mean, 23.2 vs 18.4 points), respectively. A total of 38% of participants met the clinical criteria for separation anxiety, 28% for panic symptoms, 28% for school avoidance, 24% for social anxiety, and 17% for generalized anxiety.

In the adjusted analysis, each doubling of maternal serum PBDE-28 associated with SCARED total score (β, 2.1; 95% CI, 0.7-3.5; P =.004) and panic (β, 0.8; 95% CI, 0.3-1.2; P =.002), separation anxiety (β, 0.4; 95% CI, 0.1-0.8; P =.018), and school avoidance (β, 0.2; 95% CI, 0.02-0.4; P =.029) subscores.

For PBDE-47, each doubling associated with SCARED total scores (β, 1.6; 95% CI, 0.4-2.8; P =.008) and panic (β, 0.7; 95% CI, 0.3-1.1; P <.001) and separation anxiety (β, 0.4; 95% CI, 0.1-0.7; P =.007) subscores; PBDE-99 doubling was associated with SCARED total scores (β, 1.7; 95% CI, 0.5-2.9; P =.004) and panic (β, 0.7; 95% CI, 0.3-1.1; P =0.000) and separation anxiety (β, 0.4; 95% CI, 0.1-0.7; P =.003) subscores; PBDE-100 doubling was associated with panic subscores (β, 0.4; 95% CI, 0.1-0.8; P =.022); and ∑PBDE associated with panic (β, 0.6; 95% CI, 0.2-1.0; P =.007) and separation anxiety (β, 0.4; 95% CI, 0.04-0.7; P =.027) subscores.

Similar trends were observed for the relationship between PBDE congener concentrations and clinically significant SCARED scores.

For adolescent Children’s Depression Inventory (CDI) scores, PDBE-28 was associated with CDI total score and emotional problem, negative mood, functional problems, and ineffectiveness subscores (all P ≤.028) and PBDE-99 was associated with negative mood subscores (P =.038) in the adjusted analysis.

The major limitation of this study was the reliance on self-reported measures.

Study authors conclude, “We found that gestational PBDE concentrations are significantly associated with increased anxiety symptoms in young adolescents. Moreover, the effects may be stronger for specific anxiety symptoms, including panic and separation anxiety. Due to the environmental persistence of PBDEs and ubiquitous exposure, more research is needed to understand the mechanisms by which exposure produce these effects and whether these associations persist later into adolescence.”

Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.