A combined cohort analysis of prenatal exposure to phthalate mixtures and childhood asthma

Abstract

Background: Previous studies of prenatal phthalate exposure and childhood asthma are inconsistent. These studies typically model phthalates as individual, rather than co-occurring, exposures. We investigated whether prenatal phthalates are associated with childhood wheeze and asthma using a mixtures approach. Methods: We studied dyads from two prenatal cohorts in the ECHO-PATHWAYS consortium: CANDLE, recruited 2006–2011 and TIDES, recruited 2011–2013. Parents reported child respiratory outcomes at age 4–6 years: ever asthma, current wheeze (symptoms in past 12 months) and current asthma (two affirmative responses from ever asthma, recent asthma-specific medication use, and/or current wheeze). We quantified 11 phthalate metabolites in third trimester urine and estimated associations with child respiratory outcomes using weighted quantile sum (WQS) logistic regression, using separate models to estimate protective and adverse associations, adjusting for covariates. We examined effect modification by child sex and maternal asthma. Results: Of 1481 women, most identified as White (46.6%) or Black (44.6%); 17% reported an asthma history. Prevalence of ever asthma, current wheeze and current asthma in children was 12.3%, 15.8% and 12.3%, respectively. Overall, there was no adverse association with respiratory outcomes. In sex-stratified analyses, boys’ phthalate index was adversely associated with all outcomes (e.g., boys’ ever asthma: adjusted odds ratio per one quintile increase in WQS phthalate index (AOR): 1.42; 95% confidence interval (CI): 1.08, 1.85, with mono-ethyl phthalate (MEP) weighted highest). Adverse associations were also observed in dyads without maternal asthma history, driven by MEP and mono-butyl phthalate (MBP), but not in those with maternal asthma history. We observed protective associations between the phthalate index and respiratory outcomes in analysis of all participants (e.g., ever asthma: AOR; 95% CI: 0.81; 0.68, 0.96), with di(2-ethylhexyl)phthalate (DEHP) metabolites weighted highest. Conclusions: Results suggest effect modification by child sex and maternal asthma in associations between prenatal phthalate mixtures and child asthma and wheeze.

Second-Trimester Placental and Thyroid Hormones Are Associated With Cognitive Development From Ages 1 to 3 Years

“…In the full cohort only, female infants had slightly higher mean scores in infant cognitive development and communication. In the pilot study, maternal BMI was 1.25-fold higher in women carrying females vs women carrying males, and there was a higher incidence of childhood asthma as compared to the full cohort (40% vs 15%) [ 46 ]. hCG was slightly higher in women carrying females, consistent with previous knowledge [ 39 , 47 ].…”

Maternal exposure to PM2.5 during pregnancy and asthma risk in early childhood

“…Child asthma was reported via the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire and other study questionnaires that assessed respiratory health at the age 4–6 study visit in each cohort. 14 , 15 The primary outcome, ever asthma, reflected an affirmative response to the question “Has your child ever had asthma?” Two secondary outcomes were also examined: current wheeze and current asthma. Current wheeze was defined as an affirmative response to “Has your child had wheezing or whistling in the chest in the last 12 months?” Current asthma was defined as having at least 2 of the following 3: ever asthma, current wheeze, and asthma-specific medication use.…”

A Comprehensive Assessment of Associations between Prenatal Phthalate Exposure and the Placental Transcriptomic Landscape

“…Detailed methods of phthalate measurements within this cohort have been described previously ( Adgent et al. 2020 ).…”

“…Specific gravity was determined using a handheld refractometer. Phthalate measurements were adjusted for specific gravity, and the log concentration (in nanograms per milliliter) was used in our models, as was described previously ( Adgent et al. 2020 ).…”

“…2005 ). Recent studies also suggest increased odds of negative childhood outcomes, including eczema development, asthma development in males ( Adgent et al. 2020 ), decreased mental and motor development scores and increased internalizing behaviors ( Whyatt et al.…”