0000000000263814
AUTHOR
Mercedes Espada
Thyroid Function in Early Pregnancy, Child IQ, and Autistic Traits: A Meta-Analysis of Individual Participant Data
Context: Low maternal free T4 (FT4) has been associated with poor child neurodevelopment in some single-center studies. Evidence remains scarce for the potential adverse effects of high FT4 and whether associations differ in countries with different iodine status. Objective: To assess the association of maternal thyroid function in early pregnancy with child neurodevelopment in countries with a different iodine status. Design, Setting, and Participants: Meta-analysis of individual participant data from 9036 mother–child pairs from three prospective population-based birth cohorts: INMA [Infancia y Medio Ambiente (Environment and Childhood project) (Spain)], Generation R (Netherlands), and AL…
Maternal Perfluoroalkyl Substances, Thyroid Hormones, and DIO Genes: A Spanish Cross-sectional Study
Results of studies on perfluoroalkyl substances (PFASs) and thyroid hormones (THs) are heterogeneous, and the mechanisms underlying the action of PFASs to target THs have not been fully characterized. We examined the relation between first-trimester maternal PFAS and TH levels and the role played by polymorphisms in the iodothyronine deiodinase 1 (DIO1) and 2 (DIO2) genes in this association. Our sample comprised 919 pregnant Spanish women (recruitment = 2003-2008) with measurements of perfluorohexanesulfonic acid (PFHxS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), thyroid-stimulating hormone (TSH), total triiodothyronine (TT3), and fr…
Factors associated with second-hand smoke exposure in non-smoking pregnant women in Spain: self-reported exposure and urinary cotinine levels.
The aim of this study was to evaluate the main sources of and sociodemographic factors associated with second-hand smoke (SHS) exposure, assessed both by questionnaire and by urinary cotinine (UC) levels, in non-smoking pregnant women. We conducted a cross-sectional study in pregnant women from 4 different regions in Spain. A total of 1783 non-smoking pregnant women completed a questionnaire about their previous smoking habit and SHS exposure in their 3rd trimester of pregnancy and provided a urine sample for measuring UC levels. We used logistic regression models to assess the relationship between several sociodemographic variables and some potential sources of SHS exposure. In addition, w…
Determinants of self-reported smoking and misclassification during pregnancy, and analysis of optimal cut-off points for urinary cotinine: a cross-sectional study
10 p. Objectives: To estimate the prevalence and factors associated with smoking and misclassification in pregnant women from INMA (INfancia y Medio Ambiente, Environment and Childhood) project, Spain, and to assess the optimal cut-offs for urinary cotinine (UC) that best distinguish daily and occasional smokers with varying levels of second-hand smoke (SHS) exposure.-- Design: We used logistic regression models to study the relationship between sociodemographic variables and self-reported smoking and misclassification (self-reported non-smokers with UC >50 ng/ml). Receiver operating characteristic (ROC) curves were used to calculate the optimal cut-off point for discriminating smokers. The…
Associations of maternal circulating 25-hydroxyvitamin D3 concentration with pregnancy and birth outcomes
Objective To investigate the association of maternal circulating 25-hydroxyvitamin D3 [25(OH)D3] concentration with pregnancy and birth outcomes. Design Prospective cohort study. Setting Four geographical areas of Spain, 2003–2008. Population Of 2382 mother–child pairs participating in the INfancia y Medio Ambiente (INMA) Project. Methods Maternal circulating 25(OH)D3 concentration was measured in pregnancy (mean [SD] 13.5 [2.2] weeks of gestation). We tested associations of maternal 25(OH)D3 concentration with pregnancy and birth outcomes. Main outcome measures Gestational diabetes mellitus (GDM), preterm delivery, caesarean section, fetal growth restriction (FGR) and small-for-gestational…
Second-hand smoke exposure in 4-year-old children in Spain: Sources, associated factors and urinary cotinine
Introduction Second-hand smoke exposure (SHS) in children remains as a major pollution problem, with important consequences for children's health. This study aimed to identify the sources of exposure to SHS among 4-year-old children, comparing self-reports to a urinary biomarker of exposure, and characterize the most important variables related to SHS exposure in this population. Methods 4-year-old children's exposure to SHS was assessed by a parental-reported questionnaire and by urinary cotinine (UC) measurements in 1757 participants from 4 different areas of the Spanish INMA (INfancia y Medio Ambiente – Environment and Childhood) Project. The questionnaire about SHS included information …
Association of Maternal Iodine Status With Child IQ: A Meta-Analysis of Individual Participant Data
Abstract Context Although the consequences of severe iodine deficiency are beyond doubt, the effects of mild to moderate iodine deficiency in pregnancy on child neurodevelopment are less well established. Objective To study the association between maternal iodine status during pregnancy and child IQ and identify vulnerable time windows of exposure to suboptimal iodine availability. Design Meta-analysis of individual participant data from three prospective population-based birth cohorts: Generation R (Netherlands), INMA (Spain), and ALSPAC (United Kingdom); pregnant women were enrolled between 2002 and 2006, 2003 and 2008, and 1990 and 1992, respectively. Setting General community. Participa…
Association between exposure to organochlorine compounds and maternal thyroid status: Role of the iodothyronine deiodinase 1 gene.
Introduction: Exposure to organochlorine compounds (OCs) may interfere with thyroid hormone (TH) homeostasis. The disruption of the deiodinase (DIO) enzymes has been proposed as a mechanism of action. Aim: To evaluate the association between exposure to OCs and TH status in pregnant women, as well as to explore the role of genetic variations in the DIO1 and DIO2 genes. Methods: The study population (n = 1128) was composed of pregnant women who participated in the INMA Project (Spain, 2003–2006). Hexachlorobenzene (HCB), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4´-DDE), b-hexachlorocyclohexane (b-HCH), polychlorobiphenyl (PCB) congeners 138, 153 and 180, thyroid stimulating hormone (T…
Iodine intake from supplements and diet during pregnancy and child cognitive and motor development: the INMA Mother and Child Cohort Study
BackgroundThe effect of mild-to-moderate maternal iodine deficiency on the neuropsychological development of their offspring is uncertain. We aimed to assess the association between iodine status during pregnancy and the cognitive and motor development of children at 4–5 years.MethodsWe conducted a prospective cohort study in four Spanish regions with recruitment of pregnant women between 2003 and 2008 and follow-up of their children up to 4–5 years (mean (SD)=4.8 (0.6)). Cognitive and motor function was assessed in 1803 children using the McCarthy Scales of Children’s Abilities. Dietary iodine and supplementation were measured through questionnaires twice during pregnancy. Urinary iodine c…
Vitamin D Status in Pregnancy and Determinants in a Southern European Cohort Study
Background Population-based data on vitamin D status in pregnancy in southern European countries are scarce. We assessed the prevalence and determinants of vitamin D insufficiency and deficiency in pregnancy in Spain. Methods Plasma 25-hydroxyvitamin D3 (25(OH)D3) concentration was measured at the first trimester of gestation in 2,036 pregnant women from several geographical areas of Spain (latitude 39–42°N). Uni- and multivariable regression models were conducted to identify predictors of circulating 25(OH)D3 concentration and vitamin D insufficiency (20–30 ng/mL) and deficiency (<20 ng/mL). Results Thirty-one per cent and 18% of women were vitamin D insufficient and deficient, respectivel…
Synergism between exposure to mercury and use of iodine supplements on thyroid hormones in pregnant women
Objective: To evaluate the association between mercury exposure and thyroid-stimulating hormone (TSH), total triiodothyronine (TT3) and free thyroxine (FT4) levels during pregnancy as well as to explore if there is any synergic action between mercury and intake of iodine from different sources. Methods: The study population was 1407 pregnant women participating in the Spanish INMA birth cohort study. Total mercury concentrations were analyzed in cord blood. Thyroid hormones (THs) were measured in serum samples collected at 13.2 +/- 1.5 weeks of gestation. The association between mercury and TH levels was evaluated with multivariate linear regression models. Effect modification caused by iod…