Change in Volumes and Location of Preterm White Matter Injury over a Period of 15 Years.

OBJECTIVE: To evaluate whether white matter injury (WMI) volumes and spatial distribution, which are important predictors of neurodevelopmental outcomes in preterm infants, have changed over a period of 15 years. STUDY DESIGN: Five hundred and twenty-eight infants born <32 weeks' gestational age from 2 sequential prospective cohorts (cohort 1: 2006 through 2012; cohort 2: 2014 through 2019) underwent early-life (median 32.7 weeks postmenstrual age) and/or term-equivalent-age MRI (median 40.7 weeks postmenstrual age). WMI were manually segmented for quantification of volumes. There were 152 infants with WMI with 74 infants in cohort 1 and 78 in cohort 2. Multivariable linear regression models examined change in WMI volume across cohorts while adjusting for clinical confounders. Lesion maps assessed change in WMI location across cohorts. RESULTS: There was a decrease in WMI volume in cohort 2 compared with cohort 1 (ß = -0.6, 95% CI [-0.8, -0.3], P < .001) with a shift from more central to posterior location of WMI. There was a decrease in clinical illness severity of infants across cohorts. CONCLUSIONS: We found a decrease in WMI volume and shift to more posterior location in very preterm infants over a period of 15 years. This may potentially reflect more advanced maturation of white matter at the time of injury which may be related to changes in clinical practice over time.

Neurodevelopmental outcomes at 18 months of children diagnosed with CHD compared to children born very preterm.

OBJECTIVE: To compare neurodevelopmental outcomes and parent behaviour ratings of children born term with CHD to children born very preterm. METHODS: A clinical research sample of 181 children (CHD [n = 81]; very preterm [≤32 weeks; n = 100]) was assessed at 18 months. RESULTS: Children with CHD and born very preterm did not differ on Bayley-III cognitive, language, or motor composite scores, or on expressive or receptive language, or on fine motor scaled scores. Children with CHD had lower ross motor scaled scores compared to children born very preterm (p = 0.047). More children with CHD had impaired scores (<70 SS) on language composite (17%), expressive language (16%), and gross motor (14%) indices compared to children born very preterm (6%; 7%; 3%; ps < 0.05). No group differences were found on behaviours rated by parents on the Child Behaviour Checklist (1.5-5 years) or the proportion of children with scores above the clinical cutoff. English as a first language was associated with higher cognitive (p = 0.004) and language composite scores (p < 0.001). Lower median household income and English as a second language were associated with higher total behaviour problems (ps < 0.05). CONCLUSIONS: Children with CHD were more likely to display language and motor impairment compared to children born very preterm at 18 months. Outcomes were associated with language spoken in the home and household income.

Preterm Neurodevelopmental Trajectories from 18 Months to 4.5 Years.

OBJECTIVE: To assess the longitudinal trajectory of cognitive, language, and motor outcomes from 18 months to 4.5 years of age in children born very preterm. STUDY DESIGN: This was a prospective cohort study of 163 infants born very preterm (born 24-32 weeks of gestation) followed longitudinally and assessed with neurodevelopmental scales and magnetic resonance imaging of the brain. Outcomes at 18 months and 3 years were assessed with the Bayley Scales of Infant and Toddler Development, 3rd Edition, and at 4.5 years with the Wechsler Preschool and Primary Scale of Intelligence-III and the Movement Assessment Battery for Children. Cognitive, language, and motor outcomes were categorized as below-average, average, and above-average, and compared across time. Clinical data were analyzed using ANOVA, χ2 tests, and linear regression. RESULTS: Cognitive and language trajectories were stable from 18 months to 4.5 years for all outcome groups. Motor impairment increased over time, with a greater proportion of children having motor deficits at 4.5 years. Children with below-average cognitive and language outcomes at 4.5 years had more clinical risk factors, greater white matter injury, and lower maternal education. Children with severe motor impairment at 4.5 years were born earlier, had more clinical risk factors, and demonstrated greater white matter injury. CONCLUSIONS: Children born preterm have stable cognitive and language trajectories, while motor impairment increased at 4.5 years. These results highlight the importance of continued developmental surveillance for children born preterm into preschool age.

Early-life exposure to analgesia and 18-month neurodevelopmental outcomes in very preterm infants.

BACKGROUND: We assessed variability of analgesic use across three tertiary neonatal intensive care units (NICUs) accounting for early-life pain, quantified as number of invasive procedures. We also determined whether analgesia exposure modifies associations between early-life pain and neurodevelopment. METHODS: Multicenter prospective study of 276 very preterm infants (born <24-32 weeks' gestational age [GA]). Detailed data of number of invasive procedures and duration of analgesia exposure were collected in initial weeks after birth. Eighteen-month neurodevelopmental assessments were completed in 215 children with Bayley Scales for Infant Development-Third edition. RESULTS: Multivariable linear regressions revealed significant differences in morphine use across sites, for a given exposure to early-life pain (interaction p < 0.001). Associations between early-life pain and motor scores differed by duration of morphine exposure (interaction p = 0.01); greater early-life pain was associated with poorer motor scores in infants with no or long (>7 days) exposure, but not short exposure (≤7 days). CONCLUSIONS: Striking cross-site differences in morphine exposure in very preterm infants are observed even when accounting for early-life pain. Negative associations between greater early-life pain and adverse motor outcomes were attenuated in infants with short morphine exposure. These findings emphasize the need for further studies of optimal analgesic approaches in preterm infants. IMPACT: In very preterm neonates, both early-life exposure to pain and analgesia are associated with adverse neurodevelopment and altered brain maturation, with no clear guidelines for neonatal pain management in this population. We found significant cross-site variability in morphine use across three tertiary neonatal intensive care units in Canada. Morphine use modified associations between early-life pain and motor outcomes. In infants with no or long durations of morphine exposure, greater early-life pain was associated with lower motor scores, this relationship was attenuated in those with short morphine exposure. Further trials of optimal treatment approaches with morphine in preterm infants are warranted.

Prenatal serotonin reuptake inhibitor antidepressant exposure, SLC6A4 genetic variations, and cortisol activity in 6-year-old children of depressed mothers: A cohort study.

Prenatal exposure to maternal depression and serotonin reuptake inhibitor (SRI) antidepressants both affect the development of the hypothalamic-pituitary-adrenal (HPA) system, possibly via the neurotransmitter serotonin (5HT). In a community cohort, we investigated the impact of two factors that shape prenatal 5HT signaling (prenatal SRI [pSRI] exposure and child SLC6A4 genotype) on HPA activity at age 6 years. Generalized estimating equation (GEE) models were used to study associations between cortisol reactivity, pSRI exposure, and child SLC6A4 genotype, controlling for maternal depression, child age, and sex (48 pSRI exposed, 74 nonexposed). Salivary cortisol levels were obtained at five time points during a laboratory stress challenge: arrival at the laboratory, following two sequential developmental assessments, and then 20 and 40 min following the onset of a stress-inducing cognitive/social task. Cortisol decreased from arrival across both developmental assessments, and then increased across both time points following the stress challenge in both groups. pSRI-exposed children had lower cortisol levels across all time points. In a separate GEE model, we observed a lower cortisol stress response among children with LG /S alleles compared with children with La/La alleles, and this was particularly evident among children of mothers reporting greater third trimester depressed mood. Our findings suggest that pSRI exposure and a genetic factor associated with modulating 5HT signaling shaped HPA reactivity to a laboratory stress challenge at school age.

Ventricular Volume in Infants Born Very Preterm: Relationship with Brain Maturation and Neurodevelopment at Age 4.5 Years.

OBJECTIVE: To evaluate the relationship of quantitative ventricular volume with brain maturation and neurodevelopmental outcomes at age 4.5 years in children born very preterm. STUDY DESIGN: T1-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy were performed shortly after birth (n = 212) and at term-equivalent age (TEA) (n = 194). Intraventricular hemorrhage (IVH) grade and white matter injury (WMI) volume were measured on early T1-weighted magnetic resonance imaging (MRI) scans. Total cerebral volume and ventricular volume were quantified using the Multiple Automatically Generated Templates-Brain pipeline. At age 4.5 years, 178 children (84%) underwent cognitive and motor assessments. Multivariable linear regression was used to examine the relationships between ventricular volume and neurodevelopmental outcomes. Generalized estimating equations were used to account for repeated measures when analyzing neonatal MRI data. All models accounted for sex, postmenstrual age at scan, WMI volume, IVH grade, and total cerebral volume and were corrected for multiple comparisons. RESULTS: On early MRI, 97 infants had IVH (grade 1, n = 22; grade 2, n = 66; grade 3, n = 9), and 68 had WMI (median, 44 mm3; IQR, 21-296 mm3). IQ at 4.5 years was associated with MRI ventricular volume at the early (ß = -0.64; P < .001) and TEA (ß = -0.44, P < .001) time points. Motor outcomes were associated with ventricular volume at TEA (ß = -0.84, P = .01). Greater ventricular volume independently predicted lower fractional anisotropy in corpus callosum (genu: ß = -0.0008, P = .002; splenium: ß = -0.003, P < .001) and optic radiations (ß = -0.001, P = .004); ventricular volume did not predict the N-acetylaspartate/choline ratio. CONCLUSIONS: In children born very preterm, neonatal ventricular size was associated with 4.5-year neurodevelopmental outcomes. Our findings suggest that white matter maturation may be abnormal in the setting of enlarged ventricular size beyond that expected from concurrent brain injuries.

Lower Maternal Chronic Physiological Stress and Better Child Behavior at 18 Months: Follow-Up of a Cluster Randomized Trial of Neonatal Intensive Care Unit Family Integrated Care.

OBJECTIVE: To assess whether Family Integrated Care (FICare) in the neonatal intensive care unit improves maternal chronic physiological stress and child behavior at 18 months of corrected age for infants born preterm. STUDY DESIGN: Follow-up of a multicenter, prospective cluster-randomized controlled trial comparing FICare and standard care of children born at <33 weeks of gestation and parents, stratified by tertiary neonatal intensive care units, across Canada. Primary outcomes at 18 months of corrected age were maternal stress hormones (cortisol, ie, hair cumulative cortisol [HCC], dehydroepiandrosterone [DHEA]) assayed from hair samples. Secondary outcomes included maternal reports of parenting stress, child behaviors (Internalizing, Externalizing, Dysregulation), and observer-rated caregiving behaviors. Outcomes were analyzed using multilevel modeling. RESULTS: We included 126 mother-child dyads from 12 sites (6 FICare sites, n = 83; 6 standard care sites, n = 43). FICare intervention significantly lowered maternal physiological stress as indicated by HCC (B = -0.22 [-0.41, -0.04]) and cortisol/DHEA ratio (B = -0.25 [-0.48, -0.02]), but not DHEA (B = 0.01 [-0.11, 0.14]). Enrollment in FICare led to lower child Internalizing (B = -0.93 [-2.33, 0.02]) and Externalizing behavior T scores (B = -0.91 [-2.25, -0.01]) via improvements to maternal HCC (mediation). FICare buffered the negative effects of high maternal HCC on child Dysregulation T scores (B = -11.40 [-23.01, 0.21]; moderation). For mothers reporting high parenting stress at 18 months, FICare was related to lower Dysregulation T scores via maternal HCC; moderated mediation = -0.17 (-0.41, -0.01). CONCLUSIONS: FICare has long-term beneficial effects for mother and child, attenuating maternal chronic physiological stress, and improving child behavior in toddlerhood. CLINICAL TRIAL REGISTRATION: NCT01852695.

Interaction between Preterm White Matter Injury and Childhood Thalamic Growth.

OBJECTIVE: The purpose of this study was to determine how preterm white matter injury (WMI) and long-term thalamic growth interact to predict 8-year neurodevelopmental outcomes. METHODS: A prospective cohort of 114 children born at 24 to 32 weeks' gestational age (GA) underwent structural and diffusion tensor magnetic resonance imaging early in life (median 32 weeks), at term-equivalent age and at 8 years. Manual segmentation of neonatal WMI was performed on T1-weighted images and thalamic volumes were obtained using the MAGeT brain segmentation pipeline. Cognitive, motor, and visual-motor outcomes were evaluated at 8 years of age. Multivariable regression was used to examine the relationship among neonatal WMI volume, school-age thalamic volume, and neurodevelopmental outcomes. RESULTS: School-age thalamic volumes were predicted by neonatal thalamic growth rate, GA, sex, and neonatal WMI volume (p < 0.0001). After accounting for total cerebral volume, WMI volume remained associated with school-age thalamic volume (ß = -0.31, p = 0.005). In thalamocortical tracts, fractional anisotropy (FA) at term-equivalent age interacted with early WMI volume to predict school-age thalamic volumes (all p < 0.02). School-age thalamic volumes and neonatal WMI interacted to predict full-scale IQ (p = 0.002) and adverse motor scores among those with significant WMI (p = 0.01). Visual-motor scores were predicted by thalamic volumes (p = 0.04). INTERPRETATION: In very preterm-born children, neonatal thalamic growth and WMI volume predict school-age thalamic volumes. The emergence at term of an interaction between FA and WMI to impact school-age thalamic volume indicates dysmaturation as a mechanism of thalamic growth failure. Cognition is predicted by the interaction of WMI and thalamic growth, highlighting the need to consider multiple dimensions of brain injury in these children. ANN NEUROL 2021;90:584-594.

Location and Size of Preterm Cerebellar Hemorrhage and Childhood Development.

OBJECTIVE: To examine the association between cerebellar hemorrhage (CBH) size and location and preschool-age neurodevelopment in very preterm neonates. METHODS: Preterm magnetic resonance images of 221 very preterm neonates (median gestational age = 27.9 weeks) were manually segmented for CBH quantification and location. Neurodevelopmental assessments at chronological age 4.5 years included motor (Movement Assessment Battery for Children, 2nd Edition [MABC-2]), visuomotor integration (Beery-Buktenica Developmental Test of Visual-Motor Integration, 6th Edition), cognitive (Wechsler Primary and Preschool Scale of Intelligence, 3rd Edition), and behavioral (Child Behavior Checklist) outcomes. Multivariable linear regression models examined the association between CBH size and 4.5-year outcomes accounting for sex, gestational age, and supratentorial injury. Probabilistic maps assessed CBH location and likelihood of a lesion to predict adverse outcome. RESULTS: Thirty-six neonates had CBH: 14 (6%) with only punctate CBH and 22 (10%) with ≥1 larger CBH. CBH occurred mostly in the inferior aspect of the posterior lobes. CBH total volume was independently associated with MABC-2 motor scores at 4.5 years (ß = -0.095, 95% confidence interval = -0.184 to -0.005), with a standardized ß coefficient (-0.16) that was similar to that of white matter injury volume (standardized ß = -0.22). CBH size was similarly associated with visuomotor integration and externalizing behavior but not cognition. Voxelwise odds ratio and lesion-symptom maps demonstrated that CBH extending more deeply into the cerebellum predicted adverse motor, visuomotor, and behavioral outcomes. INTERPRETATION: CBH size and location on preterm magnetic resonance imaging were associated with reduced preschool motor and visuomotor function and more externalizing behavior independent of supratentorial brain injury in a dose-dependent fashion. The volumetric quantification and localization of CBH, even when punctate, may allow opportunity to improve motor and behavioral outcomes by providing targeted intervention. ANN NEUROL 2020;88:1095-1108.

Longitudinal neurodevelopmental outcomes in preterm twins.

BACKGROUND: Several factors contribute to neurodevelopmental outcomes in preterm infants. The aim of this study was to examine the genetic and environmental influences on long-term outcomes in preterm twins. METHODS: From a prospective cohort of 225 preterm neonates studied with MRI, 24 monozygotic and 52 dizygotic twins were included. Neurodevelopmental outcomes at 1.5 and 3 years were assessed with the Bayley-III and at 4.5 years with The Movement Assessment Battery for Children and The Wechsler Preschool and Primary Scale of Intelligence-III. RESULTS: Preterm monozygotic and dizygotic twin pairs (N = 76 neonates) had similar neurodevelopmental outcomes at all time points. Monozygotic twins (N = 24) did not show greater agreement for outcomes relative to dizygotic twins (N = 52). Twin pairs who were discordant in development (N = 12) were born at a lower gestational age and had a higher incidence of bronchopulmonary dysplasia and retinopathy of prematurity. Discordant twins become more similar in cognitive and language outcomes over time. CONCLUSIONS: Neurodevelopmental outcomes in preterm twins may relate more strongly to environmental factors than genetics. Discordant twins were born earlier and had more perinatal morbidities. Despite the initial discordance, these twin pairs become similar in outcomes over time, which may reflect the positive impact of home environment or early intervention programs. IMPACT: Neurodevelopmental outcomes in preterm twins relate more strongly to environmental factors than genetics. Monozygotic twins did not show greater agreement in outcomes relative to dizygotic twins suggesting a stronger environmental, rather than genetic, influence on development. Twin pairs who were discordant in development were born at a lower gestational age and had a higher incidence of perinatal morbidities. Despite the initial discordance, these twin pairs become more similar in cognitive and language outcomes over time, which may reflect the positive impact of early intervention programs or home environment. Neurodevelopmental outcomes in preterm twins are influenced by exposure to early-life insults or environmental stressors. The initial variability in outcomes among preterm infants is not fixed, and efforts made post-discharge from the neonatal intensive care unit can have a substantial impact on long-term outcomes.

Sensory processing and cortisol at age 4 years: Procedural pain-related stress in children born very preterm.

Children born preterm display altered sensory processing, which may manifest as hyper- and/or hypo-sensitivity to sensory information. In this vulnerable population, exposure to neonatal pain-related stress is associated with altered stress regulation, as indexed by alterations in cortisol levels. It is unknown whether sensory processing behaviors are also affected by early life adversity, and whether dysregulated cortisol is related to sensory processing problems in preterm children. We examined relationships between neonatal pain-related stress, sensory processing profiles and cortisol levels at age 4 years, and whether pathways were sex-specific. In a longitudinal prospective cohort study, N = 146 infants born 24-32 weeks gestational age were recruited from BC Women's Hospital, Vancouver, BC, Canada; neonatal factors were collected from daily chart review. At age 4 years, saliva to assay cortisol was collected three times across cognitive assessment (pre-test, during, end) and parents completed the Short Sensory Profile questionnaire. Using generalized linear modeling, independent of other neonatal factors, higher number of invasive procedures (pain/stress) was associated with more sensory processing problems (total, hypo- and hyper-sensitivity) for girls only. After accounting for neonatal factors, greater cortisol output across the assessment was associated with more total sensory processing problems in girls only, and hypersensitivity to sensory input in both boys and girls. Findings suggest that in children born very preterm, how a child responds to sensory input and cortisol reactivity to stress are related but may have different precursors. Girls may be somewhat more susceptible to neonatal pain-related stress exposure in relation to sensory processing at preschool age.

Prenatal antidepressant exposure and sex differences in neonatal corpus callosum microstructure.

Prenatal exposure to selective serotonin reuptake inhibitor (SSRI) antidepressants may influence white matter (WM) development, as previous studies report widespread microstructural alterations and reduced interhemispheric connectivity in SSRI-exposed infants. In rodents, perinatal SSRIs had sex-specific disruptions in corpus callosum (CC) axon architecture and connectivity; yet it is unknown whether SSRI-related brain outcomes in humans are sex specific. In this study, the neonate CC was selected as a region-of-interest to investigate whether prenatal SSRI exposure has sex-specific effects on early WM microstructure. On postnatal day 7, diffusion tensor imaging was used to assess WM microstructure in SSRI-exposed (n = 24; 12 male) and nonexposed (n = 48; 28 male) term-born neonates. Fractional anisotropy was extracted from CC voxels and a multivariate discriminant analysis was used to identify latent patterns differing between neonates grouped by SSRI-exposure and sex. Analysis revealed localized variations in CC fractional anisotropy that significantly discriminated neonate groups and correctly predicted group membership with an 82% accuracy. Such effects were identified across three dimensions, representing sex differences in SSRI-exposed neonates (genu, splenium), SSRI-related effects independent of sex (genu-to-rostral body), and sex differences in nonexposed neonates (isthmus-splenium, posterior midbody). Our findings suggest that CC microstructure may have a sex-specific, localized, developmental sensitivity to prenatal SSRI exposure.

Sex differences in brain connectivity and male vulnerability in very preterm children.

Evidence indicates better cognitive and behavioral outcomes for females born very preterm (≤32 weeks gestation) compared to males, but the neurophysiology underlying this apparent resiliency of the female brain remains poorly understood. Here we test the hypothesis that very preterm males express more pronounced connectivity alterations as a reflection of higher male vulnerability. Resting state MEG recordings, neonatal and psychometric data were collected from 100 children at age 8 years: very preterm boys (n = 27), very preterm girls (n = 34), full-term boys (n = 15) and full-term girls (n = 24). Neuromagnetic source dynamics were reconstructed from 76 cortical brain regions. Functional connectivity was estimated using inter-regional phase-synchronization. We performed a series of multivariate analyses to test for differences across groups as well as to explore relationships between deviations in functional connectivity and psychometric scores and neonatal factors for very preterm children. Very preterm boys displayed significantly higher (p < .001) absolute deviation from average connectivity of same-sex full-term group, compared to very preterm girls versus full-term girls. In the connectivity comparison between very preterm and full-term groups separately for boys and girls, significant group differences (p < .05) were observed for boys, but not girls. Sex differences in connectivity (p < .01) were observed in very preterm children but not in full-term groups. Our findings indicate that very preterm boys have greater alterations in resting neurophysiological network communication than girls. Such uneven brain communication disruption in very preterm boys and girls suggests that stronger connectivity alterations might contribute to male vulnerability in long-term behavioral and cognitive outcome.

Mechanical Ventilation Duration, Brainstem Development, and Neurodevelopment in Children Born Preterm: A Prospective Cohort Study.

OBJECTIVES: To determine, in children born preterm, the association of mechanical ventilation duration with brainstem development, white matter maturation, and neurodevelopmental outcomes at preschool age. STUDY DESIGN: This prospective cohort study included 144 neonates born at <30 weeks of gestation (75 male, mean gestational age 27.1 weeks, SD 1.6) with regional brainstem volumes automatically segmented on magnetic resonance imaging at term-equivalent age (TEA). The white matter maturation was assessed by diffusion tensor imaging and tract-based spatial statistics. Neurodevelopmental outcomes were assessed at 4.5 years of age using the Movement Assessment Battery for Children, 2nd Edition, and the Wechsler Primary and Preschool Scale of Intelligence, 4th Edition, full-scale IQ. The association between the duration of mechanical ventilation and brainstem development was validated in an independent cohort of children born very preterm. RESULTS: Each additional day of mechanical ventilation predicted lower motor scores (0.5-point decrease in the Movement Assessment Battery for Children, 2nd Edition, score by day of mechanical ventilation, 95% CI -0.6 to -0.3, P < .0001). Prolonged exposure to mechanical ventilation was associated with smaller pons and medulla volumes at TEA in 2 independent cohorts, along with widespread abnormalities in white matter maturation. Pons and medulla volumes at TEA predicted motor outcomes at 4.5 years of age. CONCLUSIONS: In neonates born very preterm, prolonged mechanical ventilation is associated with impaired brainstem development, abnormal white matter maturation, and lower motor scores at preschool age. Further research is needed to better understand the neural pathological mechanisms involved.

Early Procedural Pain Is Associated with Regionally-Specific Alterations in Thalamic Development in Preterm Neonates.

Very preterm human neonates are exposed to numerous invasive procedures as part of life-saving care. Evidence suggests that repetitive neonatal procedural pain precedes long-term alterations in brain development. However, to date the link between pain and brain development has limited temporal and anatomic specificity. We hypothesized that early exposure to painful stimuli during a period of rapid brain development, before pain modulatory systems reach maturity, will predict pronounced changes in thalamic development, and thereby cognitive and motor function. In a prospective cohort study, 155 very preterm neonates (82 males, 73 females) born 24-32 weeks' gestation underwent two MRIs at median postmenstrual ages 32 and 40 weeks that included structural, metabolic, and diffusion imaging. Detailed day-by-day clinical data were collected. Cognitive and motor abilities were assessed at 3 years, corrected age. The association of early (skin breaks, birth-Scan 1) and late pain (skin breaks, Scans 1-2) with thalamic volumes and N-acetylaspartate (NAA)/choline (Cho), and fractional anisotropy of white-matter pathways was assessed. Early pain was associated with slower thalamic macrostructural growth, most pronounced in extremely premature neonates. Deformation-based morphometry analyses confirmed early pain-related volume losses were localized to somatosensory regions. In extremely preterm neonates early pain was associated with decreased thalamic NAA/Cho and microstructural alterations in thalamocortical pathways. Thalamic growth was in turn related to cognitive and motor outcomes. We observed regionally-specific alterations in the lateral thalamus and thalamocortical pathways in extremely preterm neonates exposed to more procedural pain. Findings suggest a sensitive period leading to lasting alterations in somatosensory-system development.SIGNIFICANCE STATEMENT Early exposure to repetitive procedural pain in very preterm neonates may disrupt the development of regions involved in somatosensory processing, leading to poor functional outcomes. We demonstrate that early pain is associated with thalamic volume loss in the territory of the somatosensory thalamus and is accompanied by disruptions thalamic metabolic growth and thalamocortical pathway maturation, particularly in extremely preterm neonates. Thalamic growth was associated with cognitive and motor outcome at 3 years corrected age. Findings provide evidence for a developmentally sensitive period whereby subcortical structures in young neonates may be most vulnerable to procedural pain. Furthermore, results suggest that the thalamus may play a key role underlying the association between neonatal pain and poor neurodevelopmental outcomes in these high-risk neonates.

Atypical resting state neuromagnetic connectivity and spectral power in very preterm children.

BACKGROUND: Children born very preterm often display selective cognitive difficulties at school age even in the absence of major brain injury. Alterations in neurophysiological activity underpinning such difficulties, as well as their relation to specific aspects of adverse neonatal experience, remain poorly understood. In the present study, we examined interregional connectivity and spectral power in very preterm children at school age, and their relationship with clinical neonatal variables and long-term outcomes (IQ, executive functions, externalizing/internalizing behavior, visual-motor integration). METHODS: We collected resting state magnetoencephalographic (MEG) and psychometric data from a cohort at the age of 8 years followed prospectively since birth, which included three groups: Extremely Low Gestational Age (ELGA, 24-28 weeks GA n = 24, age 7.7 ± 0.38, 10 girls), Very Low Gestational Age (VLGA, 29-32 weeks GA n = 37, age 7.7 ± 0.39, 24 girls), and full-term children (38-41 weeks GA n = 39, age 7.9 ± 1.02, 24 girls). Interregional phase synchrony and spectral power were tested for group differences, and associations with neonatal and outcome variables were examined using mean-centered and behavioral Partial Least Squares (PLS) analyses, respectively. RESULTS: We found greater connectivity in the theta band in the ELGA group compared to VLGA and full-term groups, primarily involving frontal connections. Spectral power analysis demonstrated overall lower power in the ELGA and VLGA compared to full-term group. PLS indicated strong associations between neurophysiological connectivity at school age, adverse neonatal experience and cognitive performance, and behavior. Resting spectral power was associated only with behavioral scores. CONCLUSIONS: Our findings indicate significant atypicalities of neuromagnetic brain activity and connectivity in very preterm children at school age, with alterations in connectivity mainly observed only in the ELGA group. We demonstrate a significant relationship between connectivity, adverse neonatal experience, and long-term outcome, indicating that the disruption of developing neurophysiological networks may mediate relationships between neonatal events and cognitive and behavioral difficulties at school age.

Hub distribution of the brain functional networks of newborns prenatally exposed to maternal depression and SSRI antidepressants.

BACKGROUND: Prenatal maternal depression (PMD) and selective serotonin reuptake inhibitor (SSRI) antidepressants are associated with increased developmental risk in infants. Reports suggest that PMD is associated with hyperconnectivity of the insula and the amygdala, while SSRI exposure is associated with hyperconnectivity of the auditory network in the infant brain. However, associations between functional brain organization and PMD and/or SSRI exposure are not well understood. METHODS: We examined the relation between PMD or SSRI exposure and neonatal brain functional organization. Infants of control (n = 17), depressed SSRI-treated (n = 20) and depressed-only (HAM-D ≥ 8) (n = 16) women, underwent resting-state functional magnetic resonance imaging at postnatal Day 6. At 6 months, temperament was assessed using Infant Behavioral Questionnaire (IBQ). We applied GTA and partial least square regression (PLSR) to the resting-state time series to assess group differences in modularity, and connector and provincial hubs. RESULTS: Modularity was similar across all groups. The depressed-only group showed higher connector hub values in the left anterior cingulate, insula, and caudate as well as higher provincial hub values in the amygdala compared to the control group. The SSRI group showed higher provincial hub values in Heschl's gyrus relative to the depressed-only group. PLSR showed that newborns' hub values predicted 10% of the variability in infant temperament at 6 months, suggesting different developmental patterns between groups. CONCLUSIONS: Prenatal exposures to maternal depression and SSRIs have differential impacts on neonatal functional brain organization. Hub values at 6 days predict variance in temperament between infant groups at 6 months of age.

Concurrent Validity of the Bayley-III and the Peabody Developmental Motor Scales-2 at 18 Months.

Aim: To determine concurrent validity between the Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) and the Peabody Developmental Motor Scales, 2nd edition (PDMS-2). Methods: Both assessments were administered to 184 preterm children at 18 months corrected age; standard scores for total score, gross motor, and fine motor were calculated for each child. Cross-tabulation and Pearson correlation coefficient (r) determined concurrent validity between the Bayley-III and the PDMS-2 motor domains. Results: High correlations were found between total motor (r = 0.88), gross motor (r = 0.88), and fine motor scores (r = 0.79). Both assessments had 93% agreement on classification for motor impairment; 23 children were identified by both assessments as having motor impairments, but 12 children were identified differently on each assessment (7 as impaired on PDMS-2 but average on Bayley-III; 5 as impaired on Bayley-III but average on PDMS-2). Most children with motor impairments were identified as 1SD below the mean on the PDMS-2 (27/30) and Bayley-III (18/28); however, the Bayley-III identified more children 2SD below the mean (10/28) compared to the PDMS-2 (3/30). Conclusions: Both the Bayley-III and PDMS-2 identify motor delays in children; however, clinicians should be aware of the concurrent validity as each assessment may lead to differing results.

Multiple Postnatal Infections in Newborns Born Preterm Predict Delayed Maturation of Motor Pathways at Term-Equivalent Age with Poorer Motor Outcomes at 3 Years.

OBJECTIVES: To evaluate whether the number of postnatal infections is associated with abnormal white matter maturation and poorer motor neurodevelopmental outcomes at 36 months of corrected age. STUDY DESIGN: A prospective longitudinal cohort study was undertaken of 219 newborns born preterm at 24-32 weeks of gestational age recruited between 2006 and 2013 with magnetic resonance imaging of the brain both early in life and at term-equivalent age. Postnatal infection was defined as any clinical infection or positive culture ≥72 hours after birth. White matter maturation was assessed by magnetic resonance spectroscopic imaging, magnetic resonance diffusion tensor imaging, and tract-based spatial statistics. Neurodevelopmental outcomes were assessed in 175 (82% of survivors) infants with Bayley Scales of Infant and Toddler Development-III composite scores and Peabody Developmental Motor Scales at 35 months of corrected age (IQR 34-37 months). Infection groups were compared via the Fisher exact test, Kruskal-Wallis test, and generalized estimating equations. RESULTS: Of 219 neonates born preterm (median gestational age 27.9 weeks), 109 (50%) had no postnatal infection, 83 (38%) had 1 or 2 infections, and 27 (12%) had ≥3 infections. Infants with postnatal infections had more cerebellar hemorrhage. Infants with ≥3 infections had lower N-acetylaspartate/choline in the white matter and basal ganglia regions, lower fractional anisotropy in the posterior limb of the internal capsule, and poorer maturation of the corpus callosum, optic radiations, and posterior limb of the internal capsule on tract-based spatial statistics analysis as well as poorer Bayley Scales of Infant and Toddler Development-III (P = .02) and Peabody Developmental Motor Scales, Second Edition, motor scores (P < .01). CONCLUSIONS: In newborns born preterm, ≥3 postnatal infections predict impaired development of the motor pathways and poorer motor outcomes in early childhood.

Plasma Betaine Is Positively Associated with Developmental Outcomes in Healthy Toddlers at Age 2 Years Who Are Not Meeting the Recommended Adequate Intake for Dietary Choline.

Background: Choline is an important nutrient during development. However, there are limited data on dietary choline intake and status in toddlers and the relation to neurodevelopmental outcomes. Objective: This study assessed dietary choline intake and status in healthy toddlers at ages 1 and 2 y and determined the relation to neurodevelopmental outcomes. Methods: This is a secondary analysis of data from healthy toddlers enrolled in a double-blind, randomized controlled trial of long-chain polyunsaturated fatty acid supplementation between ages 1 and 2 y. Dietary intakes of betaine and choline were estimated by 3-d food records; plasma free choline, betaine, and dimethylglycine were quantified by liquid chromatography-tandem mass spectrometry. Developmental outcomes were assessed at age 2 y with the use of the Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III), Cognitive and Language composites, and the Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery-VMI). Results: The mean ± SD daily intake for total choline at age 1 y was 174 ± 56.2 mg/d and increased (P < 0.001) to 205 ± 67.5 mg/d at age 2 y. At ages 1 and 2 y, 71.8% and 55.8%, respectively, of toddlers did not meet the recommended 200-mg/d Adequate Intake (AI) for dietary choline. At age 1 y, mean ± SD plasma free choline, betaine, and dimethylglycine concentrations were 10.4 ± 3.3, 41.1 ± 15.4, and 4.1 ± 1.9 µmol/L, respectively. Plasma free choline (8.5 ± 2.3 µmol/L) and dimethylglycine (3.2 ± 1.3 µmol/L) concentrations were lower (P < 0.001) at age 2 y. Plasma betaine concentrations were positively associated with the Beery-VMI (ß = 0.270; 95% CI: 0.026, 0.513; P = 0.03) at age 2 y. Conclusions: These findings suggest that most toddlers are not meeting the recommended AI for dietary choline and that higher plasma betaine concentrations are associated with better visual-motor development at age 2 y. Further work is required to investigate choline metabolism and its role in neurodevelopment in toddlers. The trial is registered at clinicaltrials.gov as NCT01263912.