Early life Phthalate Exposure and Obesity and Cardiometabolic Traits in Childhood.

Abstract

Introduction: Phthalates are industrial chemicals with endocrine disrupting properties. Human evidence on the effects of early life phthalate exposure on obesity and cardiovascular risks is limited to a few cross-sectional studies. We evaluated the associations between early life phthalate exposure with offspring obesity and cardiometabolic risk factors in 500 mother-child pairs from the RHEA pregnancy cohort in Crete, Greece. Methods: Seven phthalate metabolites were measured in spot urine samples collected from mothers (1st trimester) and their children at 4 years of age. We calculated the sum of DEHP metabolites (MEHP, MEHHP, and MEOHP) and combined high and low molecular-weight phthalate metabolites as ΣHMWPm (ΣDEHPm and MBzP) and ΣLMWPm (MEP, MiBP, and MnBP) respectively. We measured child weight, height, waist circumference, skinfold thicknesses, blood pressure (BP) and blood levels of lipids and C-reactive protein (CRP) at 4 and 6 years. Adjusted associations were obtained via multivariable regression analyses. Results: DEHP exposure during pregnancy was associated with higher CRP (β=0.41 mg/dL; 95% CI: 0.21, 0.61) at 4 years of age but was not associated with child adiposity measures at 4 and 6 years of age. Higher levels of ΣHMWPm at 4 years corresponded with 2.46 mm greater waist circumference and 8.07 mm greater sum of skinfolds gain during follow up only in girls (p for interaction <0.05). Similarly, ΣHMWPm at 4 years was associated with lower BMI z-scores in boys (β= -0.37; 95% CI: -0.70, -0.03) and with higher BMI z-scores in girls at 6 years (β= 0.56; 95% CI: 0.06, 1.07; p for sex interaction = 0.001). Phthalate exposure in pregnancy or childhood was not associated with child blood levels of lipids or blood pressure. Conclusions: Our findings suggest that early life phthalate exposure may affect child growth and adiposity in a sex-specific manner.