Antenatal and early postnatal antecedents of parent-reported attention problems at 2 years of age

Trajectories of attention problems in preschoolers born very preterm

BACKGROUND

Children born preterm are at heightened risk for neurodevelopmental impairment, including specific deficits in attention. Few studies have investigated change over time in attention problems prior to school entry. The current study aims to describe trajectories of attention problems from age 2 through 5 years in a cohort of children born <30 weeks of gestational age (GA), identify sociodemographic, medical, and neurobehavioral characteristics associated with attention trajectories, and test whether attention problem trajectories predict the risk of a reported attention-deficit/hyperactivity disorder (ADHD) diagnosis.

METHODS

We studied 608 infants from the Neonatal Neurobehavior and Outcomes in Very Preterm Infants (NOVI) Study, a prospective, multisite study of infants born <30 weeks of GA. Parents reported on child attention problems at ages 2, 3, 4, and 5 years using the Child Behavior Checklist and the Behavior Assessment System for Children. Sociodemographic and medical characteristics were assessed via maternal interview and medical record review. Neurobehavioral characteristics were determined using neonatal and 2-year assessments. Parent report of child ADHD diagnosis was obtained. We used latent growth curve (LGC) modeling to test our study aims.

RESULTS

A linear LGC model provided the best fit to the data. The average trajectory of attention problems evidenced low initial levels of symptoms and little change over time, yet there was significant heterogeneity in both initial levels and change over time. Individual differences in trajectory parameters were associated with sociodemographic, medical, environmental, and neurobehavioral characteristics. Children with higher initial levels of attention problems as well as steeper increases in attention problems over time were more likely to have a reported ADHD diagnosis.

CONCLUSIONS

There is significant heterogeneity in trajectories of attention problems from age 2 to 5 in children born <30 weeks of GA and these differences have clinical relevance. These data could inform follow-up guidelines for preterm infants.

Pre- and postnatal antibiotic exposure and risk of developing attention deficit hyperactivity disorder-A systematic review and meta-analysis combining evidence from human and animal studies

This study investigated the effects of early antibiotic exposure on ADHD risk by (1) integrating meta-analytical evidence from human observational studies examining the association between prenatal or early postnatal antibiotic exposure on the risk of developing ADHD; and (2) reviewing evidence from experimental animal studies on the effects of early antibiotic exposure on behavior. Sixteen human studies and five rodent studies were reviewed. A quantitative meta-analysis with 10 human studies indicated an increased risk for ADHD after prenatal antibiotic exposure (summary effect estimate Hazard Ratio (HR) 1.23, 95% CI 1.09-1.38; N = 2,398,475 subjects) but not after postnatal exposure within the first two years of life (summary effect estimate HR 1.12, 95% CI 0.95-1.32; N = 1,863,867 subjects). The rodent literature suggested that peri-natal antibiotic exposure has effects on social behavior, anxiety and aggression, alongside changes in gut microbial composition. Human and rodent findings thus suggest prenatal antibiotic exposure as a possible risk factor for ADHD, and suggest that an early disruption of the gut microbiome by antibiotics may interfere with neurodevelopment.

Psychiatric Outcomes, Functioning, and Participation in Extremely Low Gestational Age Newborns at Age 15 Years

OBJECTIVE

To evaluate the prevalence, co-occurrence, sex differences, and functional correlates of DSM-5 psychiatric disorders in 15-year-old adolescents born extremely preterm.

METHOD

The Extremely Low Gestational Age Newborns (ELGAN) Study is a longitudinal study of children born <28 weeks gestation. At age 15, 670 adolescents completed the Mini-International Neuropsychiatric Interview for Children and Adolescents (MINI-KID), the Youth Self-Report, a disability scale of participation in social roles, and cognitive testing. Parents completed a family psychiatric history questionnaire.

RESULTS

The most prevalent psychiatric disorders were anxiety, attention-deficit/hyperactivity disorder, and major depression. More girls met criteria for anxiety than boys. Though 66% of participants did not meet criteria for a psychiatric disorder, 15% met criteria for 1, 9% for 2, and 8% for ≥3 psychiatric disorders. Participants with ≥2 psychiatric disorders were more likely to have repeated a grade, to have an individualized educational program, and to have a lower nonverbal IQ than those with no psychiatric disorders. Participants with any psychiatric disorder were more likely to use psychotropic medications; to have greater cognitive and functional impairment; and to have mothers who were single, were on public health insurance, and had less than a high school education. Finally, a positive family psychiatric history was identified more frequently among adolescents with ≥3 psychiatric disorders.

CONCLUSION

Among adolescents born extremely preterm, anxiety, major depression, and attention-deficit/hyperactivity disorder were the most prevalent psychiatric disorders at age 15. Adolescents with >1 psychiatric disorder were at increased risk for multiple functional and participatory challenges.

Extreme prematurity: Risk and resiliency

Individuals born extremely preterm (before 28 weeks of gestation) comprise only about 0.7% of births in the United States and an even lower proportion in other high resource countries. However, these individuals account for a disproportionate number of children with cerebral palsy, intellectual deficit, autism spectrum disorder, attention deficit hyperactivity disorder, and epilepsy. This review describes two large multiple center cohorts comprised of individuals born extremely preterm: the EPICURE cohort, recruited 1995 in the United Kingdom and the Republic of Ireland, and the Extremely Low Gestational Age Newborn (ELGAN), recruited 2002-2004 in five states in the United States. The primary focus of these studies has been neurodevelopmental disorders, but also of interest are growth, respiratory illness, and parent- and self-reported global health and well-being. Both of these studies indicate that among individuals born extremely preterm the risks of most neurodevelopmental disorders are increased. Early life factors that contribute to this risk include perinatal brain damage, some of which can be identified using neonatal head ultrasound, bronchopulmonary dysplasia, and neonatal systemic inflammation. Prenatal factors, particularly the family's socioeconomic position, also appear to contribute to risk. For most adverse outcomes, the risk is higher in males. Young adults born extremely preterm who have neurodevelopmental impairment, as compared to those without such impairment, rate their quality of life lower. However, young adults born extremely preterm who do not have neurodevelopmental impairments rate their quality of life as being similar to that of young adults born at term. Finally, we summarize the current state of interventions designed to improve the life course of extremely premature infants, with particular focus on efforts to prevent premature birth and on postnatal efforts to prevent adverse neurodevelopmental outcomes.

Family Integrated Care (FICare): Positive impact on behavioural outcomes at 18 months

BACKGROUND

Children born very preterm demonstrate behavioural challenges due to clinical factors, exposure to the high stress environment of intensive care, and separation from parents during neonatal hospitalization at a critical stage in development. Family Integrated Care (FICare) significantly reduced parent stress and anxiety, and improved neonatal outcomes.

AIMS

To examine the impact of FICare on behavioural outcomes at 18-21 months corrected age (CA), and assess possible mediation through parenting or infant growth.

STUDY DESIGN AND METHODS

A prospective cohort study enrolling infants under 33 weeks gestation and parents from the FICare cluster randomized controlled trial. Primary outcome was behaviour assessed by the Infant Toddler Social Emotional Assessment (ITSEA). Parent child variables were measured with the Nursing Child Assessment Satellite Training (NCAST), Parenting Stress Index (PSI) and infant growth.

RESULTS

Subjects included 123 FICare infants and 62 standard care controls evaluated at 18-21 months CA. FICare infants demonstrated lower ITSEA Dysregulation, indicating better self-regulation skills, compared with the control group (T-score 41.7 vs 46.6, p < 0.01). At 12 months CA, the NCAST Child subtotal score was higher and the PSI-Child Domain score was lower in FICare infants than non-FICare infants. The PSI-Child domain was identified as a possible mediator of FICare on child behaviour (mediation effect 1.28, -2.96-0.02, p = 0.044).

CONCLUSION

FICare in the NICU has a sustained effect on child behaviour, improving self-regulation at 18-21 months CA.

Genetic and epigenetic factors and early life inflammation as predictors of neurodevelopmental outcomes

Among individuals born very preterm, perinatal inflammation, particularly if sustained or recurring, is highly likely to contribute to adverse neurodevelopmental outcomes, including cerebral white matter damage, cerebral palsy, cognitive impairment, attention-deficit/hyperactivity disorder, and autism spectrum disorder. Antecedents and correlates of perinatal inflammation include socioeconomic disadvantage, maternal obesity, maternal infections, fetal growth restriction, neonatal sepsis, necrotizing enterocolitis, and prolonged mechanical ventilation. Genetic factors can modify susceptibility to perinatal inflammation and to neurodevelopmental disorders. Preliminary evidence supports a role of epigenetic markers as potential mediators of the presumed effects of preterm birth and/or its consequences on neurodevelopment later in life. Further study is needed of factors such as sex, psychosocial stressors, and environmental exposures that could modify the relationship of early life inflammation to later neurodevelopmental impairments. Also needed are pharmacological and non-pharmacological interventions to attenuate inflammation towards the goal of improving the neurodevelopment of individuals born very preterm.

N-acetylcysteine inhibits bacterial lipopeptide-mediated neutrophil transmigration through the choroid plexus in the developing brain

The etiology of neurological impairments associated with prematurity and other perinatal complications often involves an infectious or pro-inflammatory component. The use of antioxidant molecules have proved useful to protect the neonatal brain from injury. The choroid plexuses-CSF system shapes the central nervous system response to inflammation at the adult stage, but little is known on the neuroimmune interactions that take place at the choroidal blood-CSF barrier during development. We previously described that peripheral administration to neonatal mice of the TLR2 ligand PAM3CSK4 (P3C), a prototypic Gram-positive bacterial lipopeptide, induces the migration of innate immune cells to the CSF. Here we showed in neonatal rats exposed to P3C that the migration of neutrophils into the CSF, which occurred through the choroid plexuses, is abolished following administration of the antioxidant drug N-acetylcysteine. Combining light sheet microscopy imaging of choroid plexus, a differentiated model of the blood-CSF barrier, and multiplex cytokine assays, we showed that the choroidal epithelium responds to the bacterial insult by a specific pattern of cytokine secretion, leading to a selective accumulation of neutrophils in the choroid plexus and to their trafficking into CSF. N-acetylcysteine acted by blocking neutrophil migration across both the endothelium of choroidal stromal vessels and the epithelium forming the blood-CSF barrier, without interfering with neutrophil blood count, neutrophil tropism for choroid plexus, and choroidal chemokine-driven chemotaxis. N-acetylcysteine reduced the injury induced by hypoxia-ischemia in P3C-sensitized neonatal rats. Overall, the data show that a double endothelial and epithelial check point controls the transchoroidal migration of neutrophils into the developing brain. They also point to the efficacy of N-acetylcysteine in reducing the deleterious effects of inflammation-associated perinatal injuries by a previously undescribed mechanism, i.e. the inhibition of innate immune cell migration across the choroid plexuses, without interfering with the systemic inflammatory response to infection.

Cohort profile: the Neonatal Intensive Care Unit Hospital Exposures and Long-Term Health (NICU-HEALTH) cohort, a prospective preterm birth cohort in New York City

PURPOSE

The Neonatal Intensive Care Unit Hospital Exposures and Long-Term Health (NICU-HEALTH) longitudinal preterm birth cohort studies the impact of the NICU exposome on early-life development. NICU-HEALTH collects multiple biospecimens, complex observational and survey data and comprehensive multisystem outcome assessments to allow measurement of the impact of modifiable environmental exposures during the preterm period on neurodevelopmental, pulmonary and growth outcomes.

PARTICIPANTS

Moderately preterm infants without genetic or congenital anomalies and their mothers are recruited from an urban academic medical centre level IV NICU in New York City, New York, USA. Recruitment began in 2011 and continues through multiple enrolment phases to the present with goal enrolment of 400 infants. Follow-up includes daily data collection throughout the NICU stay and six follow-up visits in the first 2 years. Study retention is 77% to date, with the oldest patients turning age 8 in 2019.

FINDINGS TO DATE

NICU-HEALTH has already contributed significantly to our understanding of phthalate exposure in the NICU. Phase I produced the first evidence of the clinical impact of phthalate exposure in the NICU population. Further study identified specific sources of exposure to clinically relevant phthalate mixtures in the NICU.

FUTURE PLANS

Follow-up from age 3 to 12 is co-ordinated through integration with the Environmental Influences on Child Health Outcomes (ECHO) programme. The NICU-HEALTH cohort will generate a wealth of biomarker, clinical and outcome data from which future studies of the impact of early-life chemical and non-chemical environmental exposures can benefit. Findings from study of this cohort and other collaborating environmental health cohorts will likely translate into improvements in the hospital environment for infant development.

TRIAL REGISTRATION NUMBERS

This observational cohort is registered with ClinicalTrials.gov (NCT01420029 and NCT01963065).

Antenatal and Postnatal Determinants of Behavioural Difficulties in Early Childhood: Evidence from Growing Up in New Zealand

Behavioural difficulties during early childhood have significant implications for multiple outcomes later in life. Child behavioural difficulties at 2 years of age (N = 6246) were assessed by mothers enrolled in a longitudinal, population-based New Zealand cohort study. 10.1% of children had total difficulties scores in the abnormal range on the preschool version of the Strengths and Difficulties Questionnaire. After controlling for maternal education, poverty, and child's birth age/weight, several antenatal and postnatal maternal health and family risk factors were significant for: (i) emotional problems (antenatal maternal perceived stress, lack of periconceptional folate, and moderate to severe maternal postnatal anxiety); (ii) hyperactivity-inattention (antenatal maternal perceived stress, mothers' antenatal exposure to secondhand smoke, moderate to severe maternal postnatal anxiety, and low maternal self-evaluation); (iii) conduct problems and total difficulties (antenatal maternal perceived stress, verbal inter-parental conflict and low maternal self-evaluation). The identification of risk and protective factors associated with early childhood difficulties are vital for guiding intervention and prevention efforts.

Stability and Change in Longitudinal Associations between Child Behavior Problems and Maternal Stress in Families with Preterm Born Children, Follow-Up after a RCT-Study

The Tromsø Intervention Study on Preterms (TISP) randomized 146 preterm-born children either to the Mother-Infant Transaction Program (MITP) or to a preterm control group. Previously, significant reductions of child behavior problems and maternal stress have been reported in the intervention group. This follow-up study examines whether the MITP may have affected the longitudinal adaptation between mothers and their children from two until nine years, expressed as associations between different behavioral problems and parenting stress reported by mothers. Associations between internalizing, attentional, and social problems and different dimensions of parenting stress were analyzed in separate models that included effects of time and group status. The MITP did not influence the development of longitudinal associations as no significant three-way interaction (stress*group*time) was found. Significant stress by group interactions was only found in reports on children's attentional problems when analyzed with parent- or interaction-related stress. Mothers who had participated in the MITP reported weaker stress⁻behavior associations than control mothers. This effect was moderated by two independent variables, namely children's birthweight and years of maternal education for the parent⁻child difficult interaction stress.

Neonatal intensive care unit phthalate exposure and preterm infant neurobehavioral performance

Every year in the United States, more than 300,000 infants are admitted to neonatal intensive care units (NICU) where they are exposed to a chemical-intensive hospital environment during a developmentally vulnerable period. The neurodevelopmental impact of environmental exposure to phthalates during the NICU stay is unknown. As phthalate exposure during the third trimester developmental window has been implicated in neurobehavioral deficits in term-born children that are strikingly similar to a phenotype of neurobehavioral morbidity common among children born premature, the role of early-life phthalate exposure on the neurodevelopmental trajectory of premature infants may be clinically important. In this study, premature newborns with birth weight <1500g were recruited to participate in a prospective environmental health cohort study, NICU-HEALTH (Hospital Exposures and Long-Term Health), part of the DINE (Developmental Impact of NICU Exposures) cohort of the ECHO (Environmental influences on Child Health Outcomes) program. Seventy-six percent of eligible infants enrolled in the study. Sixty-four of 81 infants survived and are included in this analysis. 164 urine specimens were analyzed for phthalate metabolites using high-performance liquid chromatography/tandem mass spectrometry. The NICU Network Neurobehavioral Scale (NNNS) was performed prior to NICU discharge. Linear and weighted quantile sum regression quantified associations between phthalate biomarkers and NNNS performance, and between phthalate biomarkers and intensity of medical intervention. The sum of di(2-ethylhexyl) phthalate metabolites (∑DEHP) was associated with improved performance on the Attention and Regulation scales. Specific mixtures of phthalate biomarkers were also associated with improved NNNS performance. More intense medical intervention was associated with higher ∑DEHP exposure. NICU-based exposure to phthalates mixtures was associated with improved attention and social response. This suggests that the impact of phthalate exposure on neurodevelopment may follow a non-linear trajectory, perhaps accelerating the development of certain neural networks. The long-term neurodevelopmental impact of NICU-based phthalate exposure needs to be evaluated.

The antecedents and correlates of necrotizing enterocolitis and spontaneous intestinal perforation among infants born before the 28th week of gestation

OBJECTIVE

To identify antecedents of "medical" necrotizing enterocolitis (mNEC), "surgical" NEC (sNEC), and spontaneous intestinal perforation (SIP) in newborns delivered before 28 weeks gestation.

STUDY DESIGN

Prospective multicenter cohort study. During study period, 2002- 2004, women delivering before 28 weeks gestation at one of 14 participating institutions were enrolled. Well defined antenatal and postnatal variables were collected. Bivariate analyses were performed to identify candidates for developing multinomial multivariable time-oriented logistic regression models.

RESULTS

Of the 1320 infants, 5% had mNEC, 6% had sNEC, and 4% had SIP. Antecedents of mNEC included mother's identification as Black, consumption of aspirin during the pregnancy, and vaginal bleeding after the 12th week of gestation. For sNEC the antecedents were maternal self- support, obesity and anemia during the pregnancy, birth before the 24th week, birth weight ≤750gm, and receipt of fresh frozen plasma (FFP) during the first postnatal week. An infant was at increased risk of SIP if the placenta had increased syncytial knots, birth occurred before the 24th week, and received FFP during the first week.

CONCLUSIONS

Maternal and neonatal characteristics might help identify at-risk ELGANs for NEC and SIP, who then may potentially benefit from targeted preventive strategies.

Systemic inflammation on postnatal days 21 and 28 and indicators of brain dysfunction 2years later among children born before the 28th week of gestation

BACKGROUND

Systemic inflammation during the first two postnatal weeks in extremely preterm newborns (<28weeks gestation) has been associated with an increased risk of neurodevelopmental dysfunctions. Little is known, however, about the relationship between systemic inflammation during the third and fourth postnatal weeks and subsequent development.

METHODS

We measured the concentrations of 16 inflammation-related proteins in blood spots collected on postnatal days 21 (N=749) and 28 (N=697) from infants born before the 28th week of gestation and assessed at age 2years. We then sought the developmental correlates of top quartile concentrations for gestational age and day the specimen was collected. Odds ratios and 95% confidence intervals were calculated from regular or multinomial logistic regression models (as appropriate).

RESULTS

Top quartile concentrations of CRP, IL-1β, IL-6, IL-6R, TNF-R2, IL-8, ICAM-1, and TSH on both days 21 and 28 were associated with ventriculomegaly (when in the NICU) and microcephaly at age 2years. Top quartile concentrations of CRP, SAA, IL-6, TNF-R2, IL-8, and ICAM-1 were associated with mental development index (MDI) of the Bayley-II<55, while top quartile concentrations of CRP, TNF-α (inversely), IL-8, and ICAM-1 were associated with psychomotor development index (PDI)<55 CONCLUSION: Extremely preterm newborns who had systemic inflammation during the third and fourth postnatal weeks were at increased risk of ventriculomegaly during the months after birth, and of microcephaly, and low Bayley Scale scores at 2years old.