Prenatal Exposure to the Major DDT Metabolite DDE and Longitudinal Measures of Body Mass Index in Boys from Southern Mexico

Abstract

ISEE-0160 Background and Objectives: Recent data suggest that in utero exposure to DDE may reduce height and increase body mass index (BMI) in childhood, thus potentially raising the risk of adult health problems. The association between prenatal DDE exposure and growth was evaluated in 786 boys from Chiapas, a highly exposed area of Mexico. (Due to an initial study hypothesis regarding effects on other outcomes mediated by androgen-blocking, no girls were enrolled.) Median DDE levels in maternal serum at birth were 2.7 μg/g lipids. Methods: 2,629 measurements of recumbent length (cm) and weight (kg) were obtained in 2004–2005. Length and BMI (kg/m2) were age-standardized and reported as standard deviation scores (SDS). Multivariate random-effect models for longitudinal data with an unstructured covariance matrix were fitted. Models included child's age at measurement and interaction terms between age and each variable to estimate the association with rate of change (Singer & Willett, 2003. Applied Longitudinal Data Analysis, p.664). Results: Median age during follow-up was 18 months (range: 5–38); median number of measurements per subject was 3, taken 3.2 months apart (median). After adjusting for child, maternal and socioeconomic variables, and using DDE ≤ 3 μg/g as the reference, those with >9 μg/g had an increase of 0.009 SDS (standard error, SE = 0.008) in length per month (equivalent to 0.29 mm at 18 mo); the corresponding coefficient for BMI was − 0.002 (SE = 0.01) (−0.003 kg/m2 at 18 mo). Conclusion: Our results do not support the prior findings of an association of childhood length or BMI with DDE exposure.