Pain-related increase in serotonin transporter gene methylation associates with emotional regulation in 4.5-year-old preterm-born children.

AIM: The main goal of this study was to assess the association between pain-related increase in serotonin transporter gene (SLC6A4) methylation and emotional dysregulation in 4.5-year-old preterm children compared with full-term matched counterparts. METHODS: Preterm (n = 29) and full-term (n = 26) children recruited from two Italian hospitals were followed-up from October 2011 to December 2017. SLC6A4 methylation was assessed from cord blood at birth from both groups and peripheral blood at discharge for preterm ones. At 4.5 years, emotional regulation (ie, anger, fear and sadness) was assessed through an observational standardised procedure. RESULTS: Preterm children (18 females; mean age = 4.5, range = 4.3-4.8) showed greater anger display compared with full-term controls (14 females; mean age = 4.5, range = 4.4-4.9) in response to emotional stress. Controlling for adverse life events occurrence from discharge to 4.5 years and SLC6A4 methylation at birth, CpG-specific SLC6A4 methylation in the neonatal period was predictive of greater anger display in preterm children but not in full-term ones. CONCLUSION: These findings contribute to highlight how epigenetic regulation of serotonin transporter gene in response to NICU pain exposure contributes to long-lasting programming of anger regulation in preterm children.

Clinical safety of 3-T brain magnetic resonance imaging in newborns.

BACKGROUND: The effects and potential hazards of brain magnetic resonance imaging (MRI) at 3 T in newborns are debated. OBJECTIVE: Assess the impact of 3-T MRI in newborns on body temperature and physiological parameters. MATERIAL AND METHODS: Forty-nine newborns, born preterm and at term, underwent 3-T brain MRI at term-corrected age. Rectal and skin temperature, oxygen saturation and heart rate were recorded before, during and after the scan. RESULTS: A statistically significant increase in skin temperature of 0.6 °C was observed at the end of the MRI scan (P<0.01). There was no significant changes in rectal temperature, heart rate or oxygen saturation. CONCLUSION: Core temperature, heart rate and oxygen saturation in newborns were not affected by 3-T brain MR scanning.

From early stress to 12-month development in very preterm infants: Preliminary findings on epigenetic mechanisms and brain growth.

Very preterm (VPT) infants admitted to Neonatal Intensive Care Unit (NICU) are at risk for altered brain growth and less-than-optimal socio-emotional development. Recent research suggests that early NICU-related stress contributes to socio-emotional impairments in VPT infants at 3 months through epigenetic regulation (i.e., DNA methylation) of the serotonin transporter gene (SLC6A4). In the present longitudinal study we assessed: (a) the effects of NICU-related stress and SLC6A4 methylation variations from birth to discharge on brain development at term equivalent age (TEA); (b) the association between brain volume at TEA and socio-emotional development (i.e., Personal-Social scale of Griffith Mental Development Scales, GMDS) at 12 months corrected age (CA). Twenty-four infants had complete data at 12-month-age. SLC6A4 methylation was measured at a specific CpG previously associated with NICU-related stress and socio-emotional stress. Findings confirmed that higher NICU-related stress associated with greater increase of SLC6A4 methylation at NICU discharge. Moreover, higher SLC6A4 discharge methylation was associated with reduced anterior temporal lobe (ATL) volume at TEA, which in turn was significantly associated with less-than-optimal GMDS Personal-Social scale score at 12 months CA. The reduced ATL volume at TEA mediated the pathway linking stress-related increase in SLC6A4 methylation at NICU discharge and socio-emotional development at 12 months CA. These findings suggest that early adversity-related epigenetic changes might contribute to the long-lasting programming of socio-emotional development in VPT infants through epigenetic regulation and structural modifications of the developing brain.

Maternal Sensitivity Buffers the Association between SLC6A4 Methylation and Socio-Emotional Stress Response in 3-Month-Old Full Term, but not very Preterm Infants.

BACKGROUND: Very preterm (VPT) infants are hospitalized in Neonatal Intensive Care Units (NICUs) and are exposed to life-saving procedures eliciting pain-related stress. Recent research documented that pain-related stress might result in birth-to-discharge increased methylation of serotonin transporter gene (SLC6A4) in VPT infants, leading to poorer stress regulation at 3 months of age in VPT infants compared to their full-term (FT) counterparts. Maternal sensitivity is thought to support infants' stress response, but its role in moderating the effects of altered SLC6A4 methylation is unknown. MAIN AIM: To assess the role of maternal sensitivity in moderating the association between altered SLC6A4 methylation and stress response in 3-month-old VPT and FT infants. METHODS: 53 infants (27 VPTs, 26 FTs) and their mothers were enrolled. SLC6A4 methylation was obtained from peripheral blood samples at NICU discharge for VPT infants and from cord blood at birth for FT infants. At 3 months (age corrected for prematurity), both groups participated to the face-to-face still-face (FFSF) paradigm to measure both infants' stress response (i.e., negative emotionality) and maternal sensitivity. RESULTS: Maternal sensitivity did not significantly differ between VPT and FT infants' mothers. In VPT infants, higher SLC6A4 methylation at hospital discharge associates with higher negative emotionality during the FFSF. In FT infants, SLC6A4 methylation and maternal sensitivity significantly interacted to predict stress response: a positive significant association between SLC6A4 methylation and negative emotionality emerged only in FT infants of less-sensitive mothers. DISCUSSION: Although no differences emerged in caregiving behavior in the two groups of mothers, maternal sensitivity was effective in moderating the effects of SLC6A4 methylation in FT infants, but not in VPT infants at 3 months. Speculatively, the buffering effect of maternal sensitivity observed in FT infants was disrupted by the altered early mother-infant contact due to NICU stay of the VPT group. These findings indirectly support that the effects of maternal sensitivity on infants' socio-emotional development might be time dependent, and that mother-infant interventions in the NICU need to be provided precociously within a narrow sensitive period after VPT birth.

Very Preterm and Full-Term Infants' Response to Socio-Emotional Stress: The Role of Postnatal Maternal Bonding.

Very preterm (VPT) infants are at risk for altered socio-emotional stress regulation, even in the absence of perinatal complications. Moreover, becoming a mother of a VPT infant is a traumatic event, which might affect the establishment of a bonding relationship toward the infant during the postnatal period. The main aim of the present study was to assess the association between maternal postnatal bonding and socio-emotional stress response in 3-month-old VPT infants, compared to full-term (FT) controls. Thirty-three VPT and 28 FT infant-mother dyads underwent the maternal Face-to-Face Still-Face (FFSF) procedure to assess socio-emotional stress regulation. Maternal postnatal bonding was measured through the Maternal Post-Natal Attachment Scale (MPAS), which includes three scales: Quality of attachment, Absence of hostility, and Pleasure in interaction. The VPT infants exhibited less self-directed and other-directed regulatory behaviors during the Still-Face episode. Mothers of VPT infants reported lower Quality of attachment compared to FT counterparts. Importantly, higher levels of Quality of attachment were associated with more other-directed behaviors during the Still-Face episode in FT dyads, whereas this was not observed in VPT dyads. In conclusion, VPT infants might be exposed to a double-risk condition for socio-emotional development, encompassing both difficulties in stress response and the exposure to a less-than-optimal maternal bonding.

Fetal development of the corpus callosum: Insights from a 3T DTI and tractography study in a patient with segmental callosal agenesis.

Commissural embryology mechanisms are not yet completely understood. The study and comprehension of callosal dysgenesis can provide remarkable insights into embryonic or fetal commissural development. The diffusion tensor imaging (DTI) technique allows the in vivo analyses of the white-matter microstructure and is a valid tool to clarify the disturbances of brain connections in patients with dysgenesis of the corpus callosum (CC). The segmental callosal agenesis (SCAG) is a rare partial agenesis of the corpus callosum (ACC). In a newborn with SCAG the DTI and tractography analyses proved that the CC was made of two separate segments consisting respectively of the ventral part in the genu and body of the CC, connecting the frontal lobes, and the dorsal part in the CC splenium and the attached hippocampal commissure (HC), connecting the parietal lobes and the fornix. These findings support the embryological thesis of a separated origin of the ventral and the dorsal parts of the CC.

SLC6A4 promoter region methylation and socio-emotional stress response in very preterm and full-term infants.

AIM: The present study is part of a prospective micro-longitudinal research project and reports on the association between SLC6A4 methylation and socio-emotional stress response in very preterm (VPT) and full-term (FT) infants. MATERIALS & METHODS: SLC6A4 methylation was assessed at birth and discharge in 32 VPT infants, and at birth in 27 FT infants. Socio-emotional stress response (i.e., negative emotionality) was assessed at 3 months (corrected age). RESULTS: Negative emotionality was higher in VPTs compared with FT counterpart. In VPT infants only, stress response was associated with SLC6A4 methylation status at discharge, which was predictive of greater negative emotionality. CONCLUSION: The present study extends previous reports, suggesting that altered SLC6A4 methylation associates with greater socio-emotional stress sensitivity in 3-month-old VPT infants.

A Comparison of Maternal and Paternal Experiences of Becoming Parents of a Very Preterm Infant.

OBJECTIVE: To compare maternal and paternal experiences of very preterm (VPT) birth (gestational age < 32 weeks) and the NICU stay. DESIGN: Qualitative study. SETTING: Data collection took place at parents' homes 3 to 6 months after NICU discharge. PARTICIPANTS: Ten parental couples participated in the study (20 parents). All VPT infants were healthy, without any neonatal or postnatal complications or injuries. METHODS: Computer-assisted content analysis was used to highlight thematic clusters from parents' narratives, which were labeled through qualitative interpretation. RESULTS: Two main dimensions (Adjustment Process to Preterm Birth and Parental Role Assumption) and three main thematic clusters (Facing the Unexpected, Learning to Parent, and Finally Back Home) described the parental experience. Mothers focused mostly on the Finally Back Home cluster, which was characterized by moderate levels of adjustment to preterm birth and by awareness of their own maternal roles. Fathers focused mostly on the Learning to Parent cluster, which was characterized by low to moderate levels of adjustment to preterm birth and by a limited assumption of paternal role. CONCLUSION: To our knowledge, this study is unique in that we compared mothers and fathers who experienced the VPT births of their infants and described their experiences of the NICU stay. We found that the VPT birth experience for parents involves a dynamic adjustment. Differences in maternal and paternal experiences may indicate the need for tailored supportive interventions in the NICU.

Serotonin Transporter Gene (SLC6A4) Methylation Associates With Neonatal Intensive Care Unit Stay and 3-Month-Old Temperament in Preterm Infants.

Preterm birth and Neonatal Intensive Care Unit (NICU) stay are early adverse stressful experiences, which may result in an altered temperamental profile. The serotonin transporter gene (SLC6A4), which has been linked to infant temperament, is susceptible to epigenetic regulation associated with early stressful experience. This study examined a moderation model in which the exposure to NICU-related stress and SLC6A4 methylation moderated infant temperament at 3 months of age. SLC6A4 methylation at 20 CpG sites was quantified in preterm infants (N = 48) and full-term infants (N = 30) from Italian middle-class families. Results suggested that in preterm infants NICU-related stress might be associated with alterations of serotonergic tone as a consequence of SLC6A4 methylation, which in turn, might associate with temperamental difficulties assessed at 3 months of age.

The Impact of Twin Birth on Early Neonatal Outcomes.

OBJECTIVE: This study aims to describe the impact of twin birth, chorionicity, intertwin birth weight (BW) discordance and birth order on neonatal outcomes. STUDY DESIGN: We performed a hospital-based retrospective study on 2,170 twins (6.4% of all live births) and 2,217 singletons inborn 2007 to 2011. Data on neonatal characteristics, morbidities, and mortality were collected and compared. Univariate and multiple (adjusted for gestational age [GA] and gender) linear random intercept regression models were used. RESULTS: Overall, 62.3% of twins were born premature. At multiple regression, twins were similar to singletons for neonatal morbidities, but they were more likely to have lower BW and to be born by cesarean delivery. Monochorionic twins had lower GA and BW compared with dichorionic ones and were more likely to develop respiratory distress syndrome (odds ratio [OR], 1.7), hypoglycemia (OR, 3.3), need for transfusion, (OR, 3.4) but not brain abnormalities. Moderate and severe BW discordance were associated with longer length of stay and increased risk for morbidities but not for death. Birth order had no effects. CONCLUSION: Prematurity was the most common outcome in twins and accounted for the apparently increased risk in morbidities. Monochorionicity was confirmed as risk factor for lower GA and neonatal morbidities. BW discordance may play a role in developing neonatal complications and needs to be further investigated.

Survival rate and neurodevelopmental outcome of extremely premature babies: an 8-year experience of an Italian single neonatal tertiary care center.

Extremely preterm babies are at major risk for adverse neurodevelopmental outcome, being the gestational age (GA) the main determinant for a good-quality survival. Aim of this retrospective study was to investigate the neurodevelopmental outcome in a population of extremely preterm babies admitted to a single neonatal tertiary care unit over an 8-year period. All babies born between 23+0 and 25+6 weeks of GA from January 2003 until December 2010 were retrospectively enrolled. Perinatal and neonatal variables were recorded. Motor and cognitive development was assessed using the neurofunctional scale (NFS) and the Griffith's scales at 2 years. Fifty-five out of 122 infants survived to discharge. Survival rates doubled for each additional gestational week from 23 to 25: 16%, 38% and 74% at 23, 24 and 25 weeks GA respectively. Forty-six infants were evaluated at 2 years. A poor cognitive and motor outcome was observed in all babies born at 23 weeks. Griffith's general quotient (GQ) was ≥76 in 62% and ≥88 in 33% of babies born between 24 and 25 weeks. No severe motor disabilities were found in 81% of babies born between 24 and 25 weeks. Preterm premature rupture of membranes, absence of prenatal steroids, intrauterine growth restriction, male, lower GA and major brain abnormalities at magnetic resonance imaging (MRI) were significantly associated with worse NFS and lower mean GQ at 2 years of age. GA, gender and abnormal MRI findings remained significantly associated with impaired NFS at the multivariate analysis. Survival rates and neurodevelopmental outcome improved with each week of GA. These results are relevant for clinicians counselling families facing an unavoidable extremely preterm birth.

Cranial ultrasound findings in late preterm infants and correlation with perinatal risk factors.

BACKGROUND: Late preterm infants are the most represented premature babies. They are exposed to a wide spectrum of brain lesions which are often clinically silent, supporting a possible role of cerebral ultrasound screening. Aim of the study is to describe the pattern of cranial ultrasound abnormalities in late preterm infants and to define the need for cranial ultrasound according to perinatal risk factors. METHODS: A hospital-based cranial ultrasound screening was carried out by performing two scans (at 1 and 5 weeks). Unfavorable cranial ultrasound at 5 weeks was defined as either persistent periventricular hyperechogenicity or severe abnormalities. RESULTS: One thousand one hundred seventy-two infants were included. Periventricular hyperechogenicity and severe abnormalities were observed in, respectively, 19.6 % and 1 % of late preterms at birth versus 1.8 % and 1.4 % at 5 weeks. Periventricular hyperechogenicity resolved in 91.3 %. At the univariate analysis gestational age (OR 0.5, 95 % CI 0.32-0.77), Apgar score <5 at 5' (OR 15.3, 1.35-173) and comorbidities (OR 4.62, 2.39-8.98) predicted unfavorable ultrasound at 5 weeks. At the multivariate analysis the accuracy in predicting unfavorable ultrasound, estimated by combined gestational age/Apgar/comorbidities ROC curve, was fair (AUC 74.6) and increased to excellent (AUC 89.4) when ultrasound at birth was included. CONCLUSION: Gestational age and comorbitidies are the most important risk factors for detecting brain lesions. The combination of being born at 34 weeks and developing RDS represents the strongest indication to perform a cranial ultrasound. Differently from other studies, twin pregnancy doesn't represent a risk factor.

Pain-related stress during the Neonatal Intensive Care Unit stay and SLC6A4 methylation in very preterm infants.

Very preterm (VPT) infants need long-lasting hospitalization in the Neonatal Intensive Care Unit (NICU) during which they are daily exposed to pain-related stress. Alterations of DNA methylation at the promoter region of the SLC6A4 have been associated with early adverse experiences in infants. The main aim of the present work was to investigate the association between level of exposure to pain-related stress during hospitalization and changes in SLC6A4 DNA methylation at NICU discharge in VPT infants. In order to exclude the potential effect of birth status (i.e., preterm vs. full-term birth) on SLC6A4 methylation, we preliminarily assessed SLC6A4 epigenetic differences between VPT and full-term (FT) infants at birth. Fifty-six VPT and thirty-two FT infants participated in the study. The level of exposure to pain-related stress was quantified on the basis of the amount of skin-breaking procedures to which they were exposed. VPT infants were divided in two sub-groups: low-pain exposure (LPE, N = 25) and high-pain exposure (HPE, N = 31). DNA methylation was evaluated at birth for both VPT and FT infants, assessing 20 CpG sites within the SLC6A4 promoter region. The same CpG sites were re-evaluated for variations in DNA methylation at NICU discharge in LPE and HPE VPT infants. No differences in SLC6A4 CpG sites' methylation emerged between FT and VPT infants at birth. Methylation at CpG sites 5 and 6 significantly increased from birth to NICU discharge only for HPE VPT infants. Findings show that preterm birth per se is not associated with epigenetic alterations of the SLC6A4, whereas higher levels of pain-related stress exposure during NICU stay might alter the transcriptional functionality of the serotonin transporter gene.

From germinal matrix to cerebellar haemorrhage.

For many years cerebellar development after preterm birth has been poorly investigated and has been studied without taking germinal matrix-intraventricular haemorrhage into account. Advanced neuroimaging techniques like magnetic resonance imaging, as well as the use of various acoustic windows (mastoid fontanelle, occipital foramen) have allowed for in vivo diagnosis of acquired focal haemorrhagic lesions in the cerebellum of very preterm babies. The vulnerability of the cerebellum also seems to be related to specific gestational ages, i.e., between 23 and 27 weeks, when rapid growth in cerebellar volume occurs and at a much faster rate than mean brain volume increase. In this paper, the contribution of the cerebellum in long-term motor cognitive, learning and behavioural functions, including psychiatric ones, is discussed.

Intracranial haemorrhage: an incidental finding at magnetic resonance imaging in a cohort of late preterm and term infants.

BACKGROUND: Intracranial haemorrhage (ICH) in term newborns has been increasingly recognised but the occurrence in late preterm infants and the clinical presentation are still unclear. OBJECTIVE: To investigate the appearance of intracranial haemorrhage at MRI in a cohort of infants born at 34 weeks' gestation or more and to correlate MRI findings with neonatal symptoms. MATERIALS AND METHODS: We retrospectively reviewed neonatal brain MRI scans performed during a 3-year period. We included neonates ≥34 weeks' gestation with intracranial haemorrhage and compared findings with those in babies without intracranial haemorrhage. Babies were classified into three groups according to haemorrhage location: (1) infratentorial, (2) infra- and supratentorial, (3) infra- and supratentorial + parenchymal involvement. RESULTS: Intracranial haemorrhage was observed in 36/240 babies (15%). All of these 36 had subdural haemorrhage. Sixteen babies were included in group 1; 16 in group 2; 4 in group 3. All infants in groups 1 and 2 were asymptomatic except one who was affected by intraventricular haemorrhage grade 3. Among the infants in group 3, who had intracranial haemorrhage with parenchymal involvement, three of the four (75%) presented with acute neurological symptoms. Uncomplicated spontaneous vaginal delivery was reported in 20/36 neonates (56%), vacuum extraction in 4 (11%) and caesarean section in 12 (33%). Babies with intracranial haemorrhage had significantly higher gestational age (38 ± 2 weeks vs. 37 ± 2 weeks) and birth weight (3,097 ± 485 g vs. 2,803 ± 741 g) compared to babies without intracranial haemorrhage and were more likely to be delivered vaginally than by caesarian section. CONCLUSION: Mild intracranial haemorrhage (groups 1 and 2) is relatively common in late preterm and term infants, although it mostly represents an incidental finding in clinically asymptomatic babies; early neurological symptoms appear to be related to parenchymal involvement.