Prenatal exposure to endocrine disrupting chemicals is associated with altered DNA methylation in cord blood.

Prenatal exposure to endocrine disrupting chemicals can interfere with development, and has been associated with social-cognitive functioning and adverse health outcomes later in life. Exposure-associated changes of DNA methylation (DNAm) patterns have been suggested as a possible mediator of this relationship. This study investigated whether prenatal low-dose exposure to polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) is associated with altered DNAm patterns across the genome in a Western urban-industrial population. In 142 mother-infant pairs from the Duisburg Birth Cohort Study, PCBs and PCDD/Fs levels were quantified from maternal blood during late pregnancy and associated with DNAm levels in cord blood using the Illumina EPIC beadchip. The epigenome-wide association studies (EWAS) identified 32 significantly differentially methylated positions (DMPs) and eight differentially methylated regions (DMRs) associated with six congeners of PCB and PCDD in females or males (FDRs < 0.05). DMPs and DMRs mapped to genes involved in neurodevelopment, gene regulation, and immune functioning. Weighted gene correlation network analysis (WGCNA) showed 31 co-methylated modules (FDRs < 0.05) associated with one congener of PCDF levels in females. Results of both analytical strategies indicate that prenatal exposure to PCBs and PCDD/Fs is associated with altered DNAm of genes involved in neurodevelopment, gene expression and immune functioning. DNAm and gene expression levels of several of these genes were previously associated with EDC exposure in rodent models. Follow-up studies will clarify whether these epigenetic changes might contribute to the origin for adverse mental and health outcomes.

Reduction of the event-related potential P3 in preterm born 5-year-old healthy children.

OBJECTIVES: An abbreviated gestational period may interrupt intrauterine brain development and constitutes a serious risk factor. Many preterm children show some form of attention deficits in later life. However, there is ambiguity about the nature and extent of these attention deficits in the literature. Moreover, the majority of studies investigated attention functions in preterm children on a symptom based level or using neuropsychological tasks. In contrast, neurophysiological studies have been comparatively scarce which will be addressed in the current study. METHODS: We investigated attention functioning in 27 low risk preterm children and 20 term children of 5-6 years of age by using EEG recording in an attention driven task (oddball task). RESULTS: Compared with term children, preterm children showed no attention deficits on a symptom level, but failed to show an increased oddball P3. CONCLUSION: Current results suggest subclinical attentional changes in preterm children on the electrophysiological level in contrast to normal performance in attentional behavioral tests. SIGNIFICANCE: Our results emphasize to have a closer look at preterm children early in preschool age even though clinically relevant symptoms seem to be absent.

The relationship between attention and deferred imitation in 12-month-old infants.

Imitation is a frequent behavior in the first years of life, and serves both a social function (e.g., to interact with others) and a cognitive function (e.g., to learn a new skill). Infants differ in their temperament, and temperament might be related to the dominance of one function of imitation. In this study, we investigated whether temperament and deferred imitation are related in 12-month-old infants. Temperament was measured via the Infant Behavior Questionnaire Revised (IBQ-R) and parts of the Laboratory Temperament Assessment Battery (Lab-TAB). Deferred imitation was measured via the Frankfurt Imitation Test for 12-month-olds (FIT-12). Regression analyses revealed that the duration of orienting (IBQ-R) and the latency of the first look away in the Task Orientation task (Lab-TAB) predicted the infants' imitation score. These results suggest that attention-related processes may play a major role when infants start to imitate.

ATTENTION FUNCTIONING IN CHILDREN WITH PRENATAL DRUG EXPOSURE.

Children born to drug abusers are exposed to teratogenic influences on intrauterine brain development and undergo postnatal withdrawal. We investigated the interplay of different domains and levels of attention functioning in 24 prenatally exposed and 25 nonexposed children who were 5 to 6 years old. Assessment included parent ratings and neuropsychological and electrophysiological methods. Exposed children had a higher prevalence of attention deficit hyperactivity symptoms, tended to have poorer performance in an attention test battery, and showed EEG alterations in P3 and N2c. Findings suggest long-term effects of prenatal drug exposure on specific domains and on different levels of attention functioning.

Influence of Low-Level Prenatal Exposure to PCDD/Fs and PCBs on Empathizing, Systemizing and Autistic Traits: Results from the Duisburg Birth Cohort Study.

BACKGROUND: Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) are assumed to act as endocrine disruptor chemicals. Prenatal exposure to these pollutants might influence fetal steroid hormone levels, which are thought to be related to sex-typical development and autistic traits. OBJECTIVES: We examined associations of prenatal levels of PCDD/Fs and PCBs with autism traits and sex-typical behaviour in childhood. METHODS: We measured levels of PCDD/Fs and PCBs in maternal blood samples during pregnancy using gas chromatography/high-resolution mass spectrometry. Sex-typical behaviour was assessed at 9 years of age (n = 96) and autistic traits at 10 years of age using the Social Responsiveness Scale (SRS; n = 100). Multiple regression analyses were conducted to estimate the associations between prenatal exposure and outcome variables. RESULTS: Blood concentrations (WHO2005-TEq) of Æ©PCDD/Fs ranged from 2.93-46.45 pg/g lipid base (median = 12.91 pg/g lipid base) and concentrations of Æ©PCBs were in the range of 1.24-25.47 pg/g lipid base (median = 6.85 pg/g lipid base) which is within the range of German background exposure. We found significant negative associations between PCDD/F levels in maternal blood and SRS scores in the whole group (ß = -6.66, p < .05), in girls (ß = -10.98, p < .05) and, in one SRS subscale, in boys (ß = -6.86, p < .05). For PCB levels, associations with one SRS subscale were significant for the whole study group as were associations with two subscales in girls. We did not find significant associations between PCDD/F or PCB levels and sex-typical behaviour for either sex. CONCLUSIONS: In an earlier part of this study, prenatal exposure to PCDD/Fs and PCBs was found to be associated with lower testosterone levels, therefore, our findings are consistent with the idea that autism spectrum conditions are related to fetal androgen levels. Several possible mechanisms, through which PCDD/Fs and PCBs might influence autistic behaviour, are discussed.

The influence of low level pre- and perinatal exposure to PCDD/Fs, PCBs, and lead on attention performance and attention-related behavior among German school-aged children: results from the Duisburg Birth Cohort Study.

BACKGROUND: Prenatal exposure to polychlorinated biphenyls (PCBs) and lead are thought to be risk factors for attention-deficit hyperactivity disorder (ADHD), whereas the prenatal influence of polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs) on attention performance has been less studied. OBJECTIVES: Within the Duisburg Birth Cohort Study, we investigated low-level exposure to these compounds in relation to children's attention. METHODS: We measured blood levels of PCDD/Fs, PCBs and lead from pregnant mothers (32(nd) week of pregnancy) and PCDD/Fs and PCBs in breast milk (2 weeks after delivery). The attention of school-aged children (N=117) was investigated with a computer-based test battery of attention performance (KITAP) and a parent rating questionnaire of behaviors related to ADHD (FBB-ADHS). Influences of the exposure on attention were analyzed by multiple regression analyses. RESULTS: Increasing prenatal PCDD/F and PCB concentrations were significantly (p<0.05) associated with a higher number of omission errors in the subtest Divided Attention (47% and 42%; 95% confidence intervals (95%-CI): 1.08-2.00 and 1.07-1.89, respectively). Prenatal lead concentrations had few significant associations with attention performance (e.g., a 23% higher number of omission errors in the subtest Distractibility; 95%-CI: 1.00-1.51), whereas ADHD-related behavior (questionnaire based) was increased with increasing lead exposure (Overall-ADHD: 9%; 95%-CI: 1.01-1.17). ADHD-related behavior was negatively associated with prenatal PCDD/F or PCB exposures (e.g., for PCB exposure: -10%; 95%-CI: 0.82-0.99). CONCLUSIONS: Pre- and perinatal PCDD/F and PCB exposure may have subtle influences on attention performance in healthy children at low environmental levels, while behavior changes are negatively associated. Furthermore, we provide additional evidence for the impact of prenatal lead exposure on attention deficits.

Effects of attachment quality on caregiving of a parent with dementia.

OBJECTIVES: The purpose of the current study was to examine the moderating role of attachment quality on the relationship between dementia-specific stressors and: (a) caregiver distress and (b) caregiver satisfaction. METHOD: Caregivers (N = 91) of a parent with dementia completed questionnaires that assessed caregiving stressors (parental cognitive impairment and behavioral problems), attachment (early and present-day attachment) and measures of caregiver distress and satisfaction. A series of regression analyses were conducted to test the hypothesis that better attachment quality may buffer the effects of cognitive impairment and behavioral problems on the caregiver's experience of distress and enhance caregiver satisfaction. RESULTS: Results did suggest that present-day attachment moderates the effects of both cognitive impairment and behavioral problems on global distress but, contrary to our hypotheses, attachment security did not buffer the negative impact associated with these demands. Instead, secure present-day attachment was positively associated with an increased risk for emotional distress at mild levels of care-recipient cognitive impairment. Most analyses indicated no significant relationship between caregiving stressors and caregiver distress or satisfaction and few interactions based on attachment quality were found. CONCLUSIONS: Our study indicates that attachment security does not always have a protective or stress-buffering function but may amplify the effect of stressors under certain conditions. Different ways of understanding the obtained pattern of findings are discussed and additional work is required to test if secure attachment may be associated with increased resilience when the disease is more advanced. Clinical implications of the present findings are discussed.

Breast feeding initiation and duration: comparison of French and German mothers.

BACKGROUND: approximately 56% of babies in France are breast fed at birth compared with approximately 91% in Germany. Few studies have compared these neighbouring countries despite the similarities in their social systems. OBJECTIVES: to compare breast-feeding initiation and duration from birth to 3 months post partum between French and German mothers, as well as reasons for breast-feeding cessation in the first 3 months. DESIGN: mothers were contacted twice during the study: immediately after childbirth and at 3 months post partum. PARTICIPANTS: 126 French mothers were recruited during their maternity stay in hospital, and 80 German women were recruited by their midwives and contacted via regular mail. All women were primiparous. METHODS: breast-feeding rates at birth and 3 months post partum were collected and compared. In addition, reasons for breast-feeding cessation in the first 3 months were explored and analysed. RESULTS: 96% of German women initiated breast feeding at birth and 83% were still breast feeding at 3 months post partum. In comparison, 67% of French women initiated breast feeding at birth and 34% were still breast feeding at 3 months post partum. CONCLUSION: there is a need for postnatal follow-up care for French mothers who breast feed. Follow-up care available for German mothers shows encouraging results.