Ο ρόλος της φλεγμονής και της πρώιμης έκθεσης σε επίμονους οργανικούς ρύπους στη νευροανάπτυξη παιδιών στην ηλικία των 4, 6 και 11 ετών: μελέτη Μητέρας Παιδιού Κρήτης, Μελέτη ΡΕΑ

Introduction: Persistent organic pollutants (POPs) are considered to be neurotoxic, influencing the synthesis and activity of neurotransmitters and the organization of the developing brain through alterations in basic cellular signaling processes and endocrine function. Human studies on a longitudinal and/or cross-sectional level have associated exposure to POPs in utero and in early childhood with adverse neurodevelopmental outcomes, such as reduced intelligence, ADHD, decreased performance in memory, autism spectrum disorders and other behavioral problems. Inflammation is a complex natural defense mechanism by body tissues in response to injurious stimuli. This response may stop being protective for the organism and become harmful if it occurs chronically. Inflammatory markers, such as cytokines, are proteins involved in normal aspects of neurodevelopment and there is growing evidence associating them in complex, higher order neurological functions, such as cognition and memory. Imbalanced cytokine production, signaling and regulation may have various neurological consequences. A body of research has evolved around the role of prenatal cytokines as markers of risk for cognitive dysfunction in special and vulnerable populations and extensive research findings report that cytokine levels in plasma and/ or sera are altered in neurodevelopmental disorders, e.g. Autism Spectrum Disorders.The specific objectives of this thesis are the following:•To explore the role of high concentration levels of prenatal exposure to HCB, DDE and PCBs in offspring cognitive development at 4, 6 and 11 years of age.•To explore the role of high concentration levels of prenatal exposure to HCB, DDE and PCBs in offspring behavioral and emotional difficulties at 4, 6 and 11 years of age. •To explore the role of high concentration levels of several inflammatory markers (IFN-γ, IL-1β, IL-6, IL-8, IL-10, IL-17α, MΙP-1α, TNF-α) measured in child serum at 4 years of age in child cognitive development at 4, 6 and 11 years of age.•To explore the role of high concentration levels of several inflammatory markers (IFN-γ, IL-1β, IL-6, IL-8, IL-10, IL-17α, MΙP-1α, TNF-α) measured in child serum at 4 years of age in child behavioral and emotional difficulties at 4, 6 and 11 years of age.Methods: This study uses data from the Rhea Study, a prospective mother-child cohort established in 2007 in Crete, Greece. Pregnant women were recruited in the study at the time of the first ultrasound examination, around the 12th gestational week, from two public and two private prenatal clinics in Heraklion, during a twelve-month period, from 02/2007 until 02/2008. Trained midwives described in detail the study to pregnant women, obtained written informed consent, measured height, weight, and blood pressure, collected urine and blood samples, and completed a thorough questionnaire concerning participants’ diet, sociodemographic and lifestyle characteristics, and exposure to various environmental agents. Mother-child pairs were invited to participate in child follow-up assessments when the children were 18 months, 4, 6 and 11 years of age.POPs: Maternal serum samples were collected at the first prenatal visit around the 3rd and 4th month of pregnancy, in 10 ml Silicone gel separator vacutainer tubes (Becton Dickinson, UK). Tubes were centrifuged within 2 hours from blood collection at 2500rpm for 10min and were then stored in aliquots at -80°C until assayed. The POP analyses were performed in the National Institute for Health and Welfare, Chemicals and Health Unit, Kuopio, Finland with an Agilent 7000B gas chromatograph triple quadrupole mass spectrometer (GC-MS/MS). Serum concentrations of six individual PCB congeners (IUPAC numbers: 118, 138, 153, 156, 170 and 180), HCB, and DDE were determined. All the results were reported on whole weight and expressed in pg/ml serum, while samples below the limit of quantification (LOQ) were assigned the value 0.5×LOQ. LOQ was 6 pg/ml for PCB118 and PCB156; 10 pg/ml for HCB, DDE, PCB138, PCB153, PCB170, PCB180. We chose to use wet-weight levels for the POPs but adjusted for maternal serum triglycerides and cholesterol as continuous variables in all multivariable models to minimize potential biases associated with automatic lipid adjustment. POPs were treated as categorical variables. We calculated total PCB concentrations by summing the concentrations of the 6 individual PCB congeners and studied the associations of interest for the sum of PCBs. Inflammatory markers: At the 4-year-follow-up assessment, blood samples were collected by venipuncture for each child (10ml) in SST gel separator vacutainer (BD vacutainers, UK), after written parental consent. For the reduction of pain and discomfort of the children, anesthetic cream 5% EMLA with composition 2.5% lidocaine and 2.5% prilocaine (AstraZeneca, UK) was used. Analyses were performed in the Laboratory of Clinical Nutrition and Epidemiology of Diseases of Medical School, University of Crete. Blood samples were centrifuged (Kubota 4000, Japan) at 2500rpm 10min within 2 hours after collection and stored at -80o C until assayed. The Milliplex Map human high sensitivity T cell magnetic bead panel (Cat. # HSTCMAG-28SK) from Millipore (Billerica, MA) was used for the simultaneous quantification of IFN-γ IL-1β, IL-6, IL-8, IL-10, IL-17α, MIP-1α and TNF-α in the supernatants. The principle of the assay is based on the quantification of multiple bio-molecules concurrently employing fluorescent-coded magnetic beads (MagPlex-C microspheres). The microspheres were incubated with the samples and then were allowed to pass rapidly through laser systems that distinguish the different sets of microspheres and the fluorescent dyes on the reporter bio-molecules. The sensitivity of the assay for every bio-molecule was: 0.3 pg/ml IFN-γ, 0.1 pg/ml IL-1β, 0.1 pg/ml IL-6, 0.1 pg/ml IL-8, 0.6 pg/ml IL-10, 0.3 pg/ml IL-17α, 0.9 pg/ml MIP-1α and 0.2 pg/ml TNF-α. We used a limit of 4 SD based on the statistical convention that observations 4 or more SD from the expected mean can be considered to be “extreme outliers” and thus, excluded from the statistical analyses. The intra-assay precision (%CV) for all biomolecules was <5%. The inter-assay precision (%CV) for IFNγ, IL-6, IL-10 and IL-17α was <20%, for IL-1β, IL-8, MIP-1α and TNF-α was <15%. The above analyses were performed on an automated analyzer Luminex 100 connected with the Luminex xPONENT software.Cognitive development assessment at 4 years was conducted using the McCarthy Scales of Children’s Abilities (MSCA), which evaluate child development across five domains: verbal, perceptual, quantitative, memory, and motor and offers a composite index of general cognitive development. Cognitive development assessment at 6 years of age was carried out using the Raven’s Colored Progressive Matrices (RCPM), which assess non-verbal general intelligence, the Finger Tapping Test (FTT), which assess motor speed, and the Trail Making Test part A & part B (TMT-Part A & TMT-Part B), which assess visual search, speed of processing, mental flexibility, and executive functions. Cognitive ability at 11 years was carried out using the Wechsler Intelligence Scale for Children, fifth edition (WISC-V), assessing intellectual functioning in children across five Primary Index Scales [including Verbal Comprehension Index (VCI); Visual Spatial Index (VSI); Fluid Reasoning Index (FRI); Working Memory Index (WMI); and Processing Speed Index (PSI)] and the four Ancillary Index Scales [including Quantitative Reasoning Index (QRI); Nonverbal Index (NI); General Ability Index (GAI) and Cognitive Proficiency Index (CPI)]. Behavioral and emotional development were overall assessed through the parent-report questionnaires. At 4 years of age the Attention Deficit Hyperactivity Disorder Test (ADHDT) and the Strengths and Difficulties Questionnaire (SDQ) were completed by participants’ parents. The ADHDT is based on ADHD criteria of DSM-IV and provides 4 indexes, corresponding to 3 subscales (hyperactivity, inattention, impulsivity) and a total ADHD difficulties index. The SDQ is a brief screening questionnaire designed to assess behavioral strengths and difficulties in children and evaluates emotional symptoms, conduct problems, hyperactivity and inattention, peer-relationship problems, and prosocial behaviour. SDQ provides two additional composite indexes of internalizing and externalizing problems. Behavioral and emotional problems at 6and 11 years of age were assessed through Child Behaviour Checklist – Parent Report Form (CBCL) and the Conner’s Parent Rating Scale, Revised, Short Form (CPRS-R: S). The CBCL includes 6 scales that correspond to different diagnostic categories of the DSM-IV: affective problems, anxiety problems, somatic problems, attention deficit/hyperactivity problems, oppositional defiant problems, and conduct problems, and two composite indexes of internalizing and externalizing problems. The CPRS-R: S assess oppositional problems, cognitive problems/inattention, and hyperactivity, and provides an index of total ADHD symptoms.Descriptive analyses on the characteristics of the population, and the distribution of the exposures, and the outcomes were conducted. Generalized additive models were used to assess the linearity of the associations of interest. Multiple linear and logistic regression models were used to explore the associations of interest, accordingly.Results:POPs•High prenatal HCB exposure was associated with decreased performance in i) cognitive, perceptual, executive and working memory functions at the age of 4, ii) non-verbal general intelligence, processing speed and mental flexibility and motor speed at 6 years of age and iii) visual spatial, fluid reasoning, working memory, quantitative reasoning, nonverbal, general ability and cognitive proficiency functions at 11 years of age.•High maternal serum levels of PCBs were associated with offspring decreased performance in working memory tasks at preschool age, increased response time in TMT Part A and lower speed scores in FFT (non-dominant hand) at 6 years of age and lower scores in several WISC-V index scores (working memory, processing speed, quantitative reasoning, nonverbal, general ability and cognitive proficiency) at 11 years of age.•At 11 years of age we found statistically significant positive associations between high HCB levels and three behavioral scales scores in the basic models. However, in the adjusted models the estimates were weakened and it may be possible there is residual confounding implicated in the direction of the results,•No association was demonstrated between high prenatal POPs levels with behavioral outcomes at any age-time point, with the sole exception of the association of high prenatal HCB levels with child peer problems in SDQ at 4 years. •No associations were found between maternal DDE concentrations and neurodevelopmental and behavioral scores at 4 and 11 years of age. Regarding 6 years of assessment, we only found one associations of high prenatal DDE levels with increased response time in TMT Part B.•No indication for effect modification by child sex, maternal pre-pregnancy body mass index (BMI) and maternal TSH during pregnancy was found.Inflammatory Markers•Preschoolers with elevated TNF-α concentrations in serum demonstrated decreased scores in memory, memory span and working memory and preschoolers with high IFN-γ serum levels showed lower scores in memory span scale. Children at 4 years with high levels of IL-8 showed lower prosocial behavior scores. •Children with elevated levels of IFN-γ at 4 years showed increased scores in oppositional and hyperactivity scales, as well as in internalized and externalized CBCL scores at 6 years of age; high IL-1β levels at 4 years were associated with more oppositional symptoms and externalized problems at 6 years of age. We also found that increased TNF-a/IL10 ratio was related with lower inattention and ADHD scores at 6 years.•Children with high levels of IL-8 at 4 years showed increased scores in processing speed; children with high levels of IL6/IL-10 ratio at 4 years showed increased scores in visual spatial performance at 11 years. High levels of the anti-inflammatory IL-10 at 4 years were associated with increased cognitive proficiency scores; high IL6/IL-10 ratio were related to increased general ability scores at 11 years. We also found that children with high levels of IFN-γ at 4 years demonstrated increased scores in hyperactivity and ADHD scales. High IL-17α levels at 4 years were associated with increased internalized problems scales at 11 years.•Our results showed greater risk for reduced verbal performance scores for boys with high IL-17α serum concentration levels, as well as lower motor scores at 4 years for boys with high IL-6 serum concentrations. We also found greater risk for lower scores in memory and memory span scales at 4 years for overweight/obese children with high TNF-α serum concentrations. Conclusions: To conclude, the present thesis supports and extends previous knowledge that prenatal exposure to high levels of POPs can be associated with reduced offspring cognitive development. This is actually the first study highlighting the association between prenatal POPs concentration levels and child neurodevelopment across three different time points, at 4, 6 and 11 years of age, strengthening the evidence for this association. We conclude that those findings raise the possibility that exposure to HCB and PCBs may play a more crucial role in child cognition than previously considered and show new directions for research in birth cohort studies. A deeper understanding of environmental risk factors for impaired cognitive development could be of considerable public health importance because of their potential modifiability. While tens of thousands of industrial chemicals are still in use, evidence on their potential neurodevelopmental effects remains inadequate for the vast majority. Studies like the current one may signify a valuable initial step towards exploring environmental risk factors for cognitive disorders. To our best of knowledge, this the first study conducted in a general population sample of children which highlights the significant role of increased inflammatory levels during preschool years in child cognitive performance across multiple time points. In fact, whilst some studies have examined the possible link between child inflammatory biomarkers and neurodevelopment, most of them were carried out with samples of extremely premature infants or with clinical samples of children with autism spectrum disorders. Moreover, most of those studies have focused on the relationship between maternal inflammatory cytokines during pregnancy and their children's neurodevelopmental outcomes. As there are no studies to this date that explored how inflammatory biomarkers relate to measures of neurodevelopmental scores in a general population sample, these results may shed some light in new pathways of investigation. Our findings reinforce the existing evidence that elevated inflammatory activity may be involved in early pathophysiological processes, such as memory deficits at a cross-sectional level, and in behavioral difficulties at a longitudinal level. An increased understanding of the interactions between pro-and-anti-inflammatory cytokine patterns and levels, and cognitive functions could allow us to identify early at-risk children for targeted interventions and allow every child to meet their full developmental potential. Inflammatory biomarkers could also even serve as indicators and possibly lead to prognosis and therapy in order to prevent developmental delays and behavioral problems in at-risk children.Εισαγωγή: Οι Επίμονοι Οργανικοί Ρύποι (ΕΟΡ) θεωρούνται νευροτοξικοί, επηρεάζοντας τη σύνθεση και τη δραστηριότητα των νευροδιαβιβαστών και την οργάνωση του αναπτυσσόμενου εγκεφάλου μέσω μεταβολών στις βασικές διαδικασίες κυτταρικής σηματοδότησης και στην λειτουργία του ενδοκρινικού συστήματος. Μελέτες σε ανθρώπους σε διαχρονικό και/ή συγχρονικό επίπεδο έχουν συσχετίσει την έκθεση σε ΕΟΡ εντός της μήτρας και κατά την πρώιμη παιδική ηλικία με δυσμενείς νευροαναπτυξιακές εκβάσεις, όπως μειωμένη νοημοσύνη, ΔΕΠ-Υ, μειωμένη μνημονική επίδοση, διαταραχές του φάσματος του αυτισμού και άλλα συμπεριφορικά προβλήματα. Η φλεγμονή είναι ένας σύνθετος φυσικός αμυντικός μηχανισμός των ιστών του σώματος ως απόκριση σε επιβλαβή ερεθίσματα. Αυτή η απόκριση μπορεί να πάψει να είναι προστατευτική για τον οργανισμό και να γίνει επιβλαβής εάν σημειώνεται σε χρόνιο επίπεδο. Οι δείκτες φλεγμονής, όπως οι κυτοκίνες, είναι πρωτεΐνες που εμπλέκονται σε φυσιολογικές πτυχές της νευροανάπτυξης και υπάρχουν ολοένα και αυξανόμενα στοιχεία που τους συνδέουν με σύνθετες, ανώτερης τάξης νευρολογικές λειτουργίες, όπως η γνωστική λειτουργία και η μνήμη. Η μη ισορροπημένη παραγωγή, σηματοδότηση και ρύθμιση των κυτοκινών μπορεί να επιφέρει ποικίλες νευρολογικές επιπτώσεις. Ένα σύνολο ερευνών έχει εξελιχθεί γύρω από το ρόλο των προγεννητικών κυτοκινών ως δεικτών κινδύνου για γνωστική δυσλειτουργία σε ειδικούς και ευάλωτους πληθυσμούς και εκτεταμένα ερευνητικά ευρήματα αναφέρουν ότι τα επίπεδα κυτοκινών στο πλάσμα και/ή τους ορούς μεταβάλλονται στις νευροαναπτυξιακές διαταραχές, π.χ. Διαταραχές Αυτιστικού Φάσματος.Οι ειδικοί στόχοι της παρούσας διατριβής είναι οι εξής:• Η διερεύνηση του ρόλου των προγεννητικά υψηλών επιπέδων συγκέντρωσης HCB, DDE και PCBs στη γνωστική ανάπτυξη των παιδιών σε ηλικία 4, 6 και 11 ετών.• Η διερεύνηση του ρόλου των προγεννητικά υψηλών επιπέδων συγκέντρωσης HCB, DDE και PCBs στις συμπεριφορικές και συναισθηματικές δυσκολίες των παιδιών σε ηλικία 4, 6 και 11 ετών.• Η διερεύνηση του ρόλου των υψηλών επιπέδων συγκέντρωσης δεικτών φλεγμονής (IFN-γ, IL-1β, IL-6, IL-8, IL-10, IL-17α, MΙP-1α, TNF-α) οι οποίοι μετρώνται στον ορό των παιδιών στην ηλικία των 4 ετών στη γνωστική τους ανάπτυξη σε ηλικία 4, 6 και 11 ετών.• Η διερεύνηση του ρόλου των υψηλών επιπέδων συγκέντρωσης δεικτών φλεγμονής (IFN-γ, IL-1β, IL-6, IL-8, IL-10, IL-17α, MΙP-1α, TNF-α) που μετρώνται στον ορό των παιδιών στην ηλικία των 4 ετών στις συμπεριφορικές και συναισθηματικές δυσκολίες τους σε ηλικία 4, 6 και 11 ετών.Μέθοδος: Η παρούσα μελέτη χρησιμοποιεί δεδομένα από τη Μελέτη Ρέα, μια προοπτική μελέτη κοόρτης μητέρας-παιδιού που ξεκίνησε το 2007 στην Κρήτη. Στη μελέτη προσεγγίστηκαν έγκυες γυναίκες κατά την επίσκεψή τους για την πρώτη εξέταση υπερήχου, περίπου κατά την 12η εβδομάδα κύησης, σε δύο δημόσιες και δύο ιδιωτικές μαιευτικές κλινικές του Ηρακλείου, κατά τη διάρκεια δωδεκάμηνης περιόδου, από 02/2007 έως 02/2008. Εκπαιδευμένες μαίες περιέγραψαν λεπτομερώς τη μελέτη στις έγκυες γυναίκες, έλαβαν γραπτή συγκατάθεση, μέτρησαν ύψος, βάρος και αρτηριακή πίεση, συνέλεξαν δείγματα ούρων και αίματος και συμπλήρωσαν ένα περιεκτικό ερωτηματολόγιο σχετικά με τη διατροφή των συμμετεχουσών, τα κοινωνικοδημογραφικά χαρακτηριστικά και τα χαρακτηριστικά του τρόπου ζωής και την έκθεση σε ποικίλους περιβαλλοντικούς παράγοντες. Τα ζεύγη μητέρας-παιδιού προσκλήθηκαν να συμμετάσχουν σε αξιολογήσεις παρακολούθησης της ανάπτυξης των παιδιών όταν εκείνα ήταν 18 μηνών, 4, 6 και 11 ετών.POPs: Δείγματα μητρικού ορού κατά την πρώτη προγεννητική επίσκεψη γύρω στον 3ο και 4ο μήνα της εγκυμοσύνης συνελέχθησαν, σε φιαλίδια των 10 ml με γέλη σιλικόνης για διαχωρισμό (Becton Dickinson, UK). Τα φιαλίδια φυγοκεντρήθηκαν εντός 2 ωρών από τη συλλογή αίματος στα 2500 rpm για 10 λεπτά και στη συνέχεια αποθηκεύτηκαν σε δείγματα στους -80°C μέχρι την ανάλυσή τους. Οι αναλύσεις των ΕΟΡ πραγματοποιήθηκαν στο National Institute for Health and Welfare, Chemicals and Health Unit, στο Kuopio της Φινλανδίας με φασματογράφο μάζας τριπλού τετραπόλου αερίου χρωματογράφου Agilent 7000B (GC-MS/MS). Προσδιορίστηκαν οι συγκεντρώσεις στον ορό έξι μεμονωμένων ισομερών PCBs (IUPAC numbers: 118, 138, 153, 156, 170 και 180), HCB και DDE. Όλα τα αποτελέσματα περιγράφηκαν σε ολικό βάρος και εκφράστηκαν σε pg/ml ορού, ενώ στα δείγματα κάτω από το όριο ποσοτικοποίησης (LOQ) αποδόθηκε η τιμή 0,5×LOQ. Το LOQ ήταν 6 pg/ml για τα PCB118 και PCB156, 10 pg/ml για HCB, DDE, PCB138, PCB153, PCB170, PCB180. Επιλέξαμε να χρησιμοποιήσουμε επίπεδα νωπού βάρους για τους ΕΟΡ, αλλά προσαρμοσμένα για τα τριγλυκερίδια και τη χοληστερόλη του μητρικού ορού ως συνεχείς μεταβλητές σε όλα τα πολυπαραγοντικά μοντέλα προκειμένου να ελαχιστοποιήσουμε πιθανά σφάλματα μεροληψίας που σχετίζονται με την αυτόματη προσαρμογή των λιπιδίων. Οι ΕΟΡ αντιμετωπίστηκαν ως κατηγορικές μεταβλητές. Υπολογίσαμε τις συνολικές συγκεντρώσεις PCB αθροίζοντας τις συγκεντρώσεις των 6 μεμονωμένων PCB ισομερών και μελετήσαμε τις σχέσεις που μας ενδιαφέρουν για το άθροισμα των PCBs.Δείκτες φλεγμονής: Στην αξιολόγηση παρακολούθησης των 4 ετών, συνελέχθησαν δείγματα αίματος με φλεβοκέντηση για κάθε παιδί (10 ml) σε φιαλίδια SST με γέλη σιλικόνης για διαχωρισμό (BD vacutainers, UK), μετά από γραπτή συγκατάθεση των γονέων. Για τη μείωση του πόνου και της δυσφορίας των παιδιών χρησιμοποιήθηκε αναισθητική κρέμα 5% EMLA με σύνθεση 2,5% λιδοκαΐνη και 2,5% πριλοκαΐνη (AstraZeneca, UK). Οι αναλύσεις έλαβαν χώρα στο Εργαστήριο Κλινικής Διατροφής και Επιδημιολογίας Νοσημάτων της Ιατρικής Σχολής του Πανεπιστημίου Κρήτης. Τα δείγματα αίματος φυγοκεντρήθηκαν (Kubota 4000, Ιαπωνία) στα 2500 rpm για 10 λεπτά εντός 2 ωρών μετά τη συλλογή και φυλάχθηκαν στους -80°C έως ότου αναλυθούν. To Milliplex Map human high sensitivity T cell magnetic bead panel (Cat. # HSTCMAG-28SK) από το Millipore (Billerica, MA) χρησιμοποιήθηκε για τον ταυτόχρονο ποσοτικό προσδιορισμό των IFN-γ IL-1β, IL-6, IL-8, IL- 10, IL-17α, ΜΙΡ-1α και TNF-α στα υπερκείμενα υγρά. Η αρχή της ανάλυσης βασίζεται στον ποσοτι

Maternal depression and personality traits in association with child neuropsychological and behavioral development in preschool years: Mother-child cohort (Rhea Study) in Crete, Greece

Background: Poor perinatal maternal mental health has been linked with negative outcomes on early child development; however, the importance of maternal personality has been neglected thus far. We aimed to examine the effects of antenatal and postnatal maternal mental health, including assessment of maternal personality characteristics, on child neuropsychological and behavioral development at preschool years in a population based mother-child cohort (Rhea Study) in Crete, Greece. Method: Self-reported measures of maternal depression (EPDS), trait anxiety (STAI-Trait) and personality traits (EPQ-R) were assessed in a sample of 288 women at 28-32 weeks of gestation. A larger sample of 642 mothers completed the EPDS scale at 8 weeks postpartum. Children&apos;s neuropsychological (MSCA) and behavioral (ADHDT and SDQ) development were assessed at 4 years of age. Linear regression analyses were used to estimate the associations between the exposures and outcomes of interest after adjustment for potential confounders. Results: Regarding child neuropsychological development, increased postnatal depressive symptoms were associated with child&apos;s perceptual performance, whereas increased maternal psychoticism was linked with child&apos;s motor ability at 4 years of age. Furthermore, elevated levels of maternal depression during pregnancy and postpartum, and the predisposing personality characteristics of trait anxiety and neuroticism, were associated With children&apos;s behavioral difficulties. Limitations: A clinical diagnostic instrument for maternal mental health was not used and assessment of children&apos;s behavior was based on maternal report. Conclusion: These findings suggest that poor perinatal maternal mental health and an adverse personality profile may be associated with impaired child neuropsychological and behavioral development at preschool years

Effect of parental obesity and gestational diabetes on child neuropsychological and behavioral development at 4 years of age: the Rhea mother-child cohort, Crete, Greece

Studies have suggested an association between maternal obesity pre-pregnancy and gestational diabetes (GDM) with impaired offspring neurodevelopment, but it is not clear if these associations are explained by shared familiar characteristics. We aimed to assess the associations of maternal and paternal obesity, maternal glucose intolerance in early pregnancy and GDM, with offspring neurodevelopment at 4 years of age. We included 772 mother-child pairs from the "Rhea" Mother-Child cohort in Crete, Greece. Data on maternal/paternal body mass index (BMI) and maternal fasting serum samples for glucose and insulin measurements were collected at 12 weeks of gestation. GDM screening was performed at 24-28 weeks. Neurodevelopment at 4 years was assessed using the McCarthy Scales of Children's Abilities. Behavioral difficulties were assessed by Strengths and Difficulties Questionnaire and Attention Deficit Hyperactivity Disorder Test. Multivariate linear regression analyses showed that maternal obesity was associated with a significant score reduction in general cognitive ability (beta-coeff -4.03, 95% CI: -7.08, -0.97), perceptual performance (beta-coeff -4.60, 95% CI: -7.74, -1.47), quantitative ability (beta-coeff -4.43, 95% CI: -7.68, -1.18), and executive functions (beta-coeff -4.92, 95% CI: -8.06, -1.78) at 4 years of age, after adjustment for several confounders and paternal BMI. Maternal obesity was also associated with increased behavioral difficulties (beta-coeff 1.22, 95% CI: 0.09, 2.34) and ADHD symptoms (beta-coeff 4.28, 95% CI: 1.20, 7.36) at preschool age. Paternal obesity maternal glucose intolerance in early pregnancy and GDM was not associated with child neurodevelopment. These findings suggest that maternal obesity may impair optimal child neurodevelopment at preschool age independently of family shared characteristics

Maternal mild thyroid dysfunction and offspring cognitive and motor development from infancy to childhood: the Rhea mother-child cohort study in Crete, Greece

BACKGROUND: Maternal thyroid hormones’ supply is crucial for fetal neurodevelopment; however, the role of maternal mild thyroid dysfunction is not clear. We aimed to assess the association of maternal mild thyroid dysfunction with child neuropsychological development from infancy to early childhood. METHODS: We included 757 mother-child pairs from the prospective “Rhea” cohort on Crete, Greece. Maternal thyroid functioning was assessed by quantitative analysis of serum thyroid stimulating hormone (TSH), free thyroxine (fT4), thyroid peroxidase antibodies (TPO-Abs), and thyroglobulin antibodies (Tg-Abs) at early gestation (mean=14 weeks). Neuropsychological assessment was based on Bayley Scales of Infant Development (18 months of age), McCarthy Scales of Children’s Abilities (4 years of age), Raven’s Coloured Progressive Matrices, Trail Making Test, and Finger Tapping Test (6 years of age). RESULTS: In multivariate adjusted linear regression analyses maternal hypothyroxinemia was associated with decreased verbal scores at 4 years and reduced motor speed at 6 years of age. Maternal thyroid autoimmunity was associated with decreased child perceptual and motor ability at 4 years of age. Four trajectories of longitudinal non-verbal cognitive development were identified and children exposed to maternal thyroid autoimmunity had increased risk for belonging to an adverse trajectory (“Low”: adjusted-RRR = 2.7 95%CI: [1.4, 5.2], “High-decreasing”: adjusted-RRR = 2.2 95%CI: [1.2, 4.0], “Low-increasing”: adjusted-RRR = 1.8 95%CI: [1.0, 3.2]). CONCLUSION: Maternal hypothyroxinemia is associated with reduced offspring verbal and motor ability. Maternal thyroid autoimmunity is associated with decreased offspring perceptual performance and motor ability and increased risk for adverse non-verbal cognitive development from infancy to childhood

Cord Leptin is Associated with Neuropsychomotor Development in Childhood

Objective: Leptin is critical for central nervous system development and maturation. This study aimed to evaluate the potential regulatory role of cord leptin in the neuropsychomotor development of children ages 18 months to 6 years. Methods: This study included 424 children from a prospective mother-child cohort (Rhea Study; Crete, Greece) with available cord leptin levels and data on neurodevelopmental outcomes at 18 months (Bayley Scales of Infant and Toddler Development, Third Edition), 4 years (McCarthy Scales of Children&apos;s Abilities), and 6 years (Raven&apos;s Coloured Progressive Matrices and Trail Making Test). Multivariable linear regression models were used to explore the associations. Results: Each 10-ng/mL increase in the cord leptin level was associated with increased scores on the gross motor scale at 18 months (β coefficient: 3.8; 95% CI: 0.0-7.5), with decreased scores in the general cognitive performance (β coefficient: −3.0; 95% CI: −5.5 to −0.4), perceptual performance (β coefficient: −3.4; 95% CI: −6.0 to −9.9), working memory (β coefficient: −3.1; 95% CI: −5.7 to −0.4), executive function (β coefficient −3.1; 95% CI: −5.7 to −0.5), and functions of the posterior cortex (β coefficient: −2.7; 95% CI: −5.2 to −0.1) scales at 4 years, and with a 3.7-unit decrease in the Raven&apos;s Coloured Progressive Matrices score at 6 years (β coefficient: −3.7; 95% CI: −6.9 to −0.5). Conclusions: Increased cord leptin levels are associated with enhanced gross motor development at 18 months but decreased cognitive performance in early and middle childhood. © 2019 The Obesity Societ

Impact of prenatal exposure to cadmium on cognitive development at preschool age and the importance of selenium and iodine

The evidence regarding a potential link of low-to-moderate iodine deficiency, selenium status, and cadmium exposure during pregnancy with neurodevelopment is either contradicting or limited. We aimed to assess the prenatal impact of cadmium, selenium, and iodine on children’s neurodevelopment at 4 years of age. The study included 575 mother-child pairs from the prospective “Rhea” cohort on Crete, Greece. Exposure to cadmium, selenium and iodine was assessed by concentrations in the mother’s urine during pregnancy (median 13 weeks), measured by ICPMS. The McCarthy Scales of Children’s Abilities was used to assess children’s general cognitive score and seven different sub-scales. In multivariable-adjusted regression analysis, elevated urinary cadmium concentrations (ae&lt;yen&gt;0.8 A mu g/L) were inversely associated with children’s general cognitive score [mean change: -6.1 points (95 % CI -12; -0.33) per doubling of urinary cadmium; corresponding to similar to 0.4 SD]. Stratifying by smoking status (p for interaction 0.014), the association was restricted to smokers. Urinary selenium was positively associated with children’s general cognitive score [mean change: 2.2 points (95 % CI -0.38; 4.8) per doubling of urinary selenium; similar to 0.1 SD], although the association was not statistically significant. Urinary iodine (median 172 A mu g/L) was not associated with children’s general cognitive score. In conclusion, elevated cadmium exposure in pregnancy of smoking women was inversely associated with the children’s cognitive function at pre-school age. The results indicate that cadmium may adversely affect neurodevelopment at doses commonly found in smokers, or that there is an interaction with other toxicants in tobacco smoke. Additionally, possible residual confounding cannot be ruled out

Impact of prenatal exposure to cadmium on cognitive development at preschool age and the importance of selenium and iodine

The evidence regarding a potential link of low-to-moderate iodine deficiency, selenium status, and cadmium exposure during pregnancy with neurodevelopment is either contradicting or limited. We aimed to assess the prenatal impact of cadmium, selenium, and iodine on children's neurodevelopment at 4 years of age. The study included 575 mother-child pairs from the prospective "Rhea" cohort on Crete, Greece. Exposure to cadmium, selenium and iodine was assessed by concentrations in the mother's urine during pregnancy (median 13 weeks), measured by ICPMS. The McCarthy Scales of Children's Abilities was used to assess children's general cognitive score and seven different sub-scales. In multivariable-adjusted regression analysis, elevated urinary cadmium concentrations (≥0.8 µg/L) were inversely associated with children's general cognitive score [mean change: -6.1 points (95 % CI -12; -0.33) per doubling of urinary cadmium; corresponding to ~0.4 SD]. Stratifying by smoking status (p for interaction 0.014), the association was restricted to smokers. Urinary selenium was positively associated with children's general cognitive score [mean change: 2.2 points (95 % CI -0.38; 4.8) per doubling of urinary selenium; ~0.1 SD], although the association was not statistically significant. Urinary iodine (median 172 µg/L) was not associated with children's general cognitive score. In conclusion, elevated cadmium exposure in pregnancy of smoking women was inversely associated with the children's cognitive function at pre-school age. The results indicate that cadmium may adversely affect neurodevelopment at doses commonly found in smokers, or that there is an interaction with other toxicants in tobacco smoke. Additionally, possible residual confounding cannot be ruled out.The “Rhea” project was financially supported by European projects (EU FP6-2003-Food-3-NewGeneris, EU FP6. STREP Hiwate, EU FP7 ENV.2007.1.2.2.2. Project No 211250 Escape, EU FP7-2008-ENV-1.2.1.4 Envirogenomarkers, EU FP7-HEALTH-2009-single stage CHICOS, EU FP7 ENV.2008.1.2.1.6. Proposal No 226285 ENRIECO, EU-FP7-HEALTH-2012 Proposal No 308333 HELIX) and the Greek Ministry of Health (Program of Prevention of obesity and neurodevelopmental disorders in preschool children, in Heraklion district, Crete, Greece: 2011–2014; “Rhea Plus”: Primary Prevention Program of Environmental Risk Factors for Reproductive Health, and Child Health: 2012–2015). The present study was also funded by Karolinska Institutet, the Swedish Research Council Formas (Project No. 210-2013-751), and Swedish Research Counci