scholarly journals Association of Maternal Iodine Status With Child IQ: A Meta-Analysis of Individual Participant Data

2019 ◽  
Vol 104 (12) ◽  
pp. 5957-5967 ◽  
Author(s):  
Deborah Levie ◽  
Tim I M Korevaar ◽  
Sarah C Bath ◽  
Mario Murcia ◽  
Mariana Dineva ◽  
...  
Keyword(s):  
Iodine Deficiency ◽  
Meta Analysis ◽  
Urinary Iodine ◽  
First Trimester ◽  
Individual Participant Data ◽  
Verbal Iq ◽  
Iodine Status ◽  
Child Neurodevelopment ◽  
Individual Participant ◽  
In Pregnancy

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. Participants 6180 mother-child pairs with measures of urinary iodine and creatinine concentrations in pregnancy and child IQ. Exclusion criteria were multiple pregnancies, fertility treatment, medication affecting the thyroid, and preexisting thyroid disease. Main Outcome Measure Child nonverbal and verbal IQ assessed at 1.5 to 8 years of age. Results There was a positive curvilinear association of urinary iodine/creatinine ratio (UI/Creat) with mean verbal IQ only. UI/Creat <150 µg/g was not associated with lower nonverbal IQ (−0.6 point; 95% CI: −1.7 to 0.4 points; P = 0.246) or lower verbal IQ (−0.6 point; 95% CI: −1.3 to 0.1 points; P = 0.082). Stratified analyses showed that the association of UI/Creat with verbal IQ was only present up to 14 weeks of gestation. Conclusions Fetal brain development is vulnerable to mild to moderate iodine deficiency, particularly in the first trimester. Our results show that potential randomized controlled trials investigating the effect of iodine supplementation in women with mild to moderate iodine deficiency on child neurodevelopment should begin supplementation not later than the first trimester.

scholarly journals Thyroid Function in Early Pregnancy, Child IQ, and Autistic Traits: A Meta-Analysis of Individual Participant Data

2018 ◽  
Vol 103 (8) ◽  
pp. 2967-2979 ◽  
Author(s):  
Deborah Levie ◽  
Tim I M Korevaar ◽  
Sarah C Bath ◽  
Albert Dalmau-Bueno ◽  
Mario Murcia ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Early Pregnancy ◽  
Meta Analysis ◽  
Autistic Traits ◽  
Individual Participant Data ◽  
Thyroid State ◽  
Verbal Iq ◽  
Iodine Status ◽  
Child Neurodevelopment ◽  
Individual Participant

Abstract 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 ALSPAC (Avon Longitudinal Study of Parents and Children, United Kingdom). The exclusion criteria were multiple pregnancies, fertility treatments, thyroid-interfering medication usage, and known thyroid disease. Main Outcomes Child nonverbal IQ at 5 to 8 years of age, verbal IQ at 1.5 to 8 years of age, and autistic traits within the clinical range at 5 to 8 years of age. Results FT4 &lt;2.5th percentile was associated with a 3.9-point (95% CI, −5.7 to −2.2) lower nonverbal IQ and a 2.1-point (95% CI, −4.0 to −0.1) lower verbal IQ. A suggestive association of hypothyroxinemia with a greater risk of autistic traits was observed. FT4 &gt;97.5th percentile was associated with a 1.9-fold (95% CI, 1.0 to 3.4) greater risk of autistic traits. No independent associations were found with TSH. Conclusions Low maternal FT4 was consistently associated with a lower IQ across the cohorts. Further studies are needed to replicate the findings of autistic traits and investigate the potential modifying role of maternal iodine status. FT4 seems a reliable marker of fetal thyroid state in early pregnancy, regardless of the type of immunoassay.

scholarly journals Diet and physical activity in pregnancy to prevent gestational diabetes: a protocol for an individual participant data (IPD) meta-analysis on the differential effects of interventions with economic evaluation

BMJ Open ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. e048119
Author(s):  
Dyuti Coomar ◽  
Jonathan M Hazlehurst ◽  
Frances Austin ◽  
Charlie Foster ◽  
Graham A Hitman ◽  
...  
Keyword(s):  
Physical Activity ◽  
Cost Effectiveness ◽  
Gestational Diabetes ◽  
Systematic Reviews ◽  
Meta Analysis ◽  
Individual Participant Data ◽  
Randomised Trials ◽  
Diet And Physical Activity ◽  
Individual Participant ◽  
In Pregnancy

IntroductionMothers with gestational diabetes mellitus (GDM) are at increased risk of pregnancy-related complications and developing type 2 diabetes after delivery. Diet and physical activity-based interventions may prevent GDM, but variations in populations, interventions and outcomes in primary trials have limited the translation of available evidence into practice. We plan to undertake an individual participant data (IPD) meta-analysis of randomised trials to assess the differential effects and cost-effectiveness of diet and physical activity-based interventions in preventing GDM and its complications.MethodsThe International Weight Management in Pregnancy Collaborative Network database is a living repository of IPD from randomised trials on diet and physical activity in pregnancy identified through a systematic literature search. We shall update our existing search on MEDLINE, Embase, BIOSIS, LILACS, Pascal, Science Citation Index, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects and Health Technology Assessment Database without language restriction to identify relevant trials until March 2021. Primary researchers will be invited to join the Network and share their IPD. Trials including women with GDM at baseline will be excluded. We shall perform a one and two stage random-effect meta-analysis for each intervention type (all interventions, diet-based, physical activity-based and mixed approach) to obtain summary intervention effects on GDM with 95% CIs and summary treatment–covariate interactions. Heterogeneity will be summarised using I2 and tau2 statistics with 95% prediction intervals. Publication and availability bias will be assessed by examining small study effects. Study quality of included trials will be assessed by the Cochrane Risk of Bias tool, and the Grading of Recommendations, Assessment, Development and Evaluations approach will be used to grade the evidence in the results. A model-based economic analysis will be carried out to assess the cost-effectiveness of interventions to prevent GDM and its complications compared with usual care.Ethics and disseminationEthics approval is not required. The study is registered on the International Prospective Register of Systematic Reviews (CRD42020212884). Results will be submitted for publication in peer-reviewed journals.

scholarly journals Moderate Iodine Deficiency Is Common in Pregnancy but Does Not Alter Maternal and Neonatal Thyroid Function Tests

2020 ◽  
Vol 11 ◽  
Author(s):  
Tal Schiller ◽  
Arnon Agmon ◽  
Viviana Ostrovsky ◽  
Gabi Shefer ◽  
Hilla Knobler ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Thyroid Function ◽  
Iodine Deficiency ◽  
Urinary Iodine ◽  
Iodine Content ◽  
First Trimester ◽  
Thyroid Function Tests ◽  
Neonatal Thyroid Function ◽  
Iodine Deficiency In Pregnancy ◽  
In Pregnancy

IntroductionAn Israeli national survey found that 85% of pregnant women had urinary iodine content (UIC) levels below the adequacy range (&lt;150 µg/L). Widespread desalinated water usage and no national fortification plan are possible causes. Studies assessing relationships between iodine status and maternal and neonatal thyroid function provided varying results. Our aims were to determine whether iodine deficiency was associated with altered maternal or neonatal thyroid function and the factors leading to iodine deficiency.MethodsA cross-sectional study including 100 healthy women without prior thyroid disease, in their first trimester of a singleton pregnancy were recruited from an HMO clinic in central Israel. The women were followed from their first trimester. All women completed a 24-h dietary recall and life habits questionnaires. We tested for UIC, maternal and neonatal thyroid function, maternal autoantibodies, and neonatal outcomes.ResultsMedian UIC in our cohort was 49 µg/L [25%–75% interquartile range (IQR) 16-91.5 µg/L], with 84% below adequacy range. No correlation was found between iodine deficiency and maternal or neonatal thyroid function which remained within normal ranges. Antibody status did not differ, but thyroglobulin levels were significantly higher in iodine insufficient subjects. UIC was higher in women consuming an iodine containing supplement. There was no association between UIC and dietary iodine content or water source.ConclusionsModerate iodine deficiency is common in our healthy pregnant women population. Our data imply that moderate iodine deficiency in pregnancy seem sufficient to maintain normal maternal and neonatal thyroid function.

scholarly journals Indicators of Iodine Status in Pregnancy and Postpartum in a Group of Pregnant Women from Perimarine Area of Romania

2020 ◽  
Vol 26 (2) ◽  
pp. 63-69
Author(s):  
Scrinic Olesea ◽  
Delia Corina Elena ◽  
Toma Geanina Mirela ◽  
Circo Eduard
Keyword(s):  
Pregnant Women ◽  
Iodine Deficiency ◽  
Urinary Iodine ◽  
Iodine Concentration ◽  
Iodine Intake ◽  
Iodized Salt ◽  
Urinary Iodine Concentration ◽  
Urinary Creatinine ◽  
Iodine Status ◽  
In Pregnancy

Abstract Objective: Assessment of iodine nutritional status in pregnant women in the perimarine area of Romania, a region without iodine deficiency. Adequate iodine intake is the main source for normal thyroid function, ensuring the need for maternal thyroid hormones during pregnancy, but also for the development and growth of children in the fetal and postpartum period. Material and method: Prospective study performed on 74 pregnant women in the first 2 trimesters of pregnancy, originating from the perimarin area. The following indicators of iodine status were analyzed: urinary iodine concentration (UIC), the ratio between urinary iodine concentration and urinary creatinine (UIC/UCr), the prevalence of maternal goiter and the value of neonatal TSH (thyroid stimulating hormone). Results: The mean gestational age was 11 weeks. The ways of iodine intake are: iodized salt - 59.4%, iodized salt and iodine supplements- 23%, only iodine supplements -10.8% and 6.8% consume only non-iodized salt. The median of UIC was 133.03 mcg/l considered insufficient iodine intake (normal in pregnancy UIC >150 mcg/l), but the adjustment of UIC to urinary creatinine reveals a median of 152.83 mcg/g, a value that reflects an adequate iodine intake. The prevalence of goiter was 25.6% characteristic for a moderate iodine deficiency. The prevalence of neonatal TSH >5 mIU/L was registered in 18.8% characteristic of mild iodine deficiency. Conclusions: Monitoring of the iodine nutritional status is recommended for the prevention of disorders due to iodine deficiency under the conditions of universal salt iodization. Perimarine areas considered sufficient in iodine may show variations in iodine status in subpopulations under certain physiological conditions, such as pregnancy. An indicator of iodine status of the population is UIC, but the UIC/UCr ratio may be a more optimal indicator for pregnant women, to avoid possible overestimated results of iodine deficiency in pregnancy.

scholarly journals Maternal iodine status in a multi-ethnic UK birth cohort: associations with autism spectrum disorder

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Kirsten Jade Cromie ◽  
Diane Erin Threapleton ◽  
Charles Jonathan Peter Snart ◽  
Elizabeth Taylor ◽  
Dan Mason ◽  
...  
Keyword(s):  
Autism Spectrum Disorder ◽  
Thyroid Hormones ◽  
Iodine Deficiency ◽  
Urinary Iodine ◽  
Fetal Brain ◽  
First Trimester ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Iodine Status ◽  
Increased Risk

Abstract Background Maternal iodine requirements increase during pregnancy to supply thyroid hormones essential for fetal brain development. Maternal iodine deficiency can lead to hypothyroxinemia, a reduced fetal supply of thyroid hormones which, in the first trimester, has been linked to an increased risk of autism spectrum disorder (ASD) in the child. No study to date has explored the direct link between maternal iodine deficiency and diagnosis of ASD in offspring. Methods Urinary iodine concentrations (UIC) and iodine/creatinine ratios (I:Cr) were measured in 6955 mothers at 26–28 weeks gestation participating in the Born in Bradford (BiB) cohort. Maternal iodine status was examined in relation to the probability of a Read (CTV3) code for autism being present in a child’s primary care records through a series of logistic regression models with restricted cubic splines. Results Median (inter-quartile range) UIC was 76 μg/L (46, 120) and I:Cr was 83 μg/g (59, 121) indicating a deficient population according to WHO guidelines. Ninety two children (1·3%) in our cohort had received a diagnosis of ASD by the census date. Overall, there was no evidence to support an association between I:Cr or UIC and ASD risk in children aged 8–12 years (p = 0·3). Conclusions There was no evidence of an increased clinical ASD risk in children born to mothers with mild-to-moderate iodine deficiency at 26 weeks gestation. Alternative functional biomarkers of exposure and a wider range of conditions may provide further insight.

scholarly journals The Effect of Tetanus-Diphtheria-Acellular-Pertussis Immunization During Pregnancy on Infant Antibody Responses: Individual-Participant Data Meta-Analysis

2021 ◽  
Vol 12 ◽  
Author(s):  
Bahaa Abu-Raya ◽  
Kirsten Maertens ◽  
Flor M. Munoz ◽  
Petra Zimmermann ◽  
Nigel Curtis ◽  
...  
Keyword(s):  
Meta Analysis ◽  
Geometric Mean ◽  
Individual Participant Data ◽  
Primary Immunization ◽  
Booster Immunization ◽  
Vaccine Responses ◽  
Chi Squared ◽  
Tdap Vaccine ◽  
Individual Participant ◽  
In Pregnancy

BackgroundImmunization with tetanus-diphtheria-acellular pertussis (Tdap) vaccine in pregnancy is increasingly recommended. We determined the effect of Tdap immunization in pregnancy on infants’ vaccine responses.MethodsIndividual-participant data meta-analysis of ten studies (n=1884) investigating infants’ antibody response to routine immunizations following Tdap immunization in pregnancy was performed. Geometric mean ratios (GMRs) of antigen-specific immunoglobulin G (IgG) levels were calculated using mixed-effects models. Seroprotection rates were compared using chi-squared tests.ResultsInfants of Tdap-immunized women had significantly lower IgG against pertussis toxin (GMR 0.65; 95%CI 0.57-0.74), filamentous haemagglutinin (FHA) (0.68; 0.53-0.87), pertactin (0.65; 0.58-0.72) and fimbria 2/3 (FIM2/3) (0.41; 0.32-0.52) after primary immunization, compared with infants of unimmunized women. These lower levels persisted after booster immunization for FHA (0.72; 0.61-0.84) and FIM2/3 (0.53; 0.29-0.96). After primary immunization, infants of Tdap-immunized women had lower seroprotection rates against diphtheria (90% [843/973] vs 98% [566/579]; p&lt;0.001) and invasive pneumococcal disease (IPD) caused by 5 Streptococcus pneumoniae (SPN) serotypes (SPN5, SPN6B, SPN9V, SPN19A, SPN23F), and higher seroprotection rates against Haemophilus influenzae type b (short-term and long-term seroprotection rates, 86%[471/547] vs 76%[188/247] and 62%[337/547] vs 49%(121/247), respectively, all p=0.001). After booster immunization, seroprotection rates against diphtheria and tetanus were 99% (286/288) and (618/619) in infants of Tdap-immunized women, respectively.ConclusionsInfants of Tdap-immunized women in pregnancy had lower IgG levels against pertussis, diphtheria and some SPN serotypes after their immunization compared with infants of unimmunized women. Enhanced surveillance of pertussis, diphtheria and IPD in infants is needed to determine the clinical significance of these findings.Systematic Review RegistrationCRD42017079171.

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