Are Extremely Low Gestational Age Newborns Born to Obese Women at Increased Risk of Cerebral Palsy at 2 Years?

Genetic pathways in cerebral palsy: a review of the implications for precision diagnosis and understanding disease mechanisms

ABSTRACT

Cerebral palsy is a diagnostic term utilized to describe a group of permanent disorders affecting movement and posture. Patients with cerebral palsy are often only capable of limited activity, resulting from non-progressive disturbances in the fetal or neonatal brain. These disturbances severely impact the child's daily life and impose a substantial economic burden on the family. Although cerebral palsy encompasses various brain injuries leading to similar clinical outcomes, the understanding of its etiological pathways remains incomplete owing to its complexity and heterogeneity. This review aims to summarize the current knowledge on the genetic factors influencing cerebral palsy development. It is now widely acknowledged that genetic mutations and alterations play a pivotal role in cerebral palsy development, which can be further influenced by environmental factors. Despite continuous research endeavors, the underlying factors contributing to cerebral palsy remain are still elusive. However, significant progress has been made in genetic research that has markedly enhanced our comprehension of the genetic factors underlying cerebral palsy development. Moreover, these genetic factors have been categorized based on the identified gene mutations in patients through clinical genotyping, including thrombosis, angiogenesis, mitochondrial and oxidative phosphorylation function, neuronal migration, and cellular autophagy. Furthermore, exploring targeted genotypes holds potential for precision treatment. In conclusion, advancements in genetic research have substantially improved our understanding of the genetic causes underlying cerebral palsy. These breakthroughs have the potential to pave the way for new treatments and therapies, consequently shaping the future of cerebral palsy research and its clinical management. The investigation of cerebral palsy genetics holds the potential to significantly advance treatments and management strategies. By elucidating the underlying cellular mechanisms, we can develop targeted interventions to optimize outcomes. A continued collaboration between researchers and clinicians is imperative to comprehensively unravel the intricate genetic etiology of cerebral palsy.

Association of maternal pre-pregnancy or first trimester body mass index with neurodevelopmental impairment or death in extremely low gestational age neonates

OBJECTIVE

To compare the rates of death or survival with severe neurodevelopmental impairment (sNDI) at 2 years among extremely preterm infants in relation to pre-pregnancy or first-trimester maternal body mass index (BMI).

METHODS

This retrospective cohort study included extremely preterm infants (gestational age 220/7-266/7 weeks). The study was conducted at National Institute of Child Health and Human Development Neonatal Research Network sites. The primary outcome was death or sNDI at 2 years.

RESULTS

Data on the primary outcome were available for 1208 children. Death or sNDI was not different among the three groups: 54.9% in normal, 56.1% in overweight, and 53.4% in obese group (p = 0.39). There was no significant difference in mortality, sNDI, moderate/severe cerebral palsy, Bayley Scales of Infant Development (BSID)-III cognitive composite score <70, BSID-III language composite score <70 in adjusted models.

CONCLUSION

Neurodevelopmental outcome was not significantly associated with maternal pre-pregnancy BMI among extreme preterm infants.

The association of maternal overweight on long-term neurodevelopmental outcomes in premature infants (< 29 weeks) at 18-24 months corrected age

OBJECTIVE

To determine the association of maternal pre-pregnancy body mass index (BMI) and neurodevelopmental impairment (NDI) at 18-24 months corrected age (CA) in infants born < 29 weeks gestation.

STUDY DESIGN

Infants born between 2005 and 2015 at < 29 weeks gestation were included. BMI was categorized into BMI1 [18.5-24.9 kg/m2], BMI2 [25-29.9 kg/m2], BMI3 [ ≥ 30 kg/m2]. Primary outcome was death or NDI (Bayley-III scores < 85, cerebral palsy, hearing or visual impairment). Univariate and multivariate analysis were used.

RESULTS

There were 315 infants in BMI1, 235 in BMI2, and 147 in BMI3 groups. Adjusted odds ratio (aOR) of death or NDI in BMI2 vs. BMI1 and BMI3 vs BMI1 groups were 1.33 (95% CI 0.86-2.06) and 0.76 (95% CI 0.47-1.22). Adjusted odds ratio of Bayley-III language composite < 85 was 2.06 (95% CI 1.28-3.32).

CONCLUSION

Pre-pregnancy BMI was not associated with death or NDI in extremely preterm infants. Infants born to overweight mothers had higher odds of low language scores.

Early Growth and Cognitive Development in Children Born Preterm: Relevance of Maternal Body Mass Index

OBJECTIVE

Maternal prepregnancy body mass index (BMI) represents a surrogate marker of fetal exposures to the maternal metabolism during pregnancy. Yet, it remains poorly understood whether this marker indicates risk of altered trajectories in postnatal growth and development in children born preterm. This study aimed to determine whether maternal prepregnancy BMI is associated with altered growth and development in children born preterm.

STUDY DESIGN

A retrospective cohort study evaluated prepregnancy BMI as the exposure for childhood outcomes using linear regression and mixed effects models. The 38 children included in this follow-up evaluation originally participated in a prospective, observational cohort study to determine longitudinal levels of lipid species in preterm human milk expressed by women who delivered prior to 32 weeks. Childhood outcomes in this study were anthropometric measures during hospitalization (n = 38), after discharge through 36 months (n = 34) and Bayley-III developmental scores through 18 months corrected age (n = 26).

RESULTS

In 38 children born prior to 32 weeks, higher maternal prepregnancy BMI was independently associated with higher preterm infant growth velocity during hospitalization, but not associated with in-hospital change in length or head circumference and/or postdischarge growth. In univariate linear regression models, higher maternal BMI was associated with lower cognitive scores at 18 months corrected age. This significant association remained in an adjusted model accounting for relevant influences on early childhood development.

CONCLUSION

Increasing maternal prepregnancy BMI may reflect risk of altered growth and cognitive development in children born preterm.

KEY POINTS

· Maternal BMI was associated with early preterm infant weight gain.. · Maternal BMI was not associated with postdischarge growth.. · Increased maternal BMI may be associated with lower cognitive function scores in offspring..

Pre-pregnancy BMI-associated miRNA and mRNA expression signatures in the placenta highlight a sexually-dimorphic response to maternal underweight status

Pre-pregnancy body mass index (BMI) is associated with adverse pregnancy and neonatal health outcomes, with differences in risk observed between sexes. Given that the placenta is a sexually dimorphic organ and critical regulator of development, examining differences in placental mRNA and miRNA expression in relation to pre-pregnancy BMI may provide insight into responses to maternal BMI in utero. Here, genome-wide mRNA and miRNA expression levels were assessed in the placentas of infants born extremely preterm. Differences in expression were evaluated according to pre-pregnancy BMI status (1) overall and (2) in male and female placentas separately. Overall, 719 mRNAs were differentially expressed in relation to underweight status. Unexpectedly, no genes were differentially expressed in relation to overweight or obese status. In male placentas, 572 mRNAs were associated with underweight status, with 503 (70%) overlapping genes identified overall. Notably, 43/572 (8%) of the mRNAs associated with underweight status in male placentas were also gene targets of two miRNAs (miR-4057 and miR-128-1-5p) associated with underweight status in male placentas. Pathways regulating placental nutrient metabolism and angiogenesis were among those enriched in mRNAs associated with underweight status in males. This study is among the first to highlight a sexually dimorphic response to low pre-pregnancy BMI in the placenta.

Placental programming, perinatal inflammation, and neurodevelopment impairment among those born extremely preterm

Individuals born extremely preterm are at significant risk for impaired neurodevelopment. After discharge from the neonatal intensive care, associations between the child's well-being and factors in the home and social environment become increasingly apparent. Mothers' prenatal health and socioeconomic status are associated with neurodevelopmental outcomes, and emotional and behavioral problems. Research on early life risk factors and on mechanisms underlying inter-individual differences in neurodevelopment later in life can inform the design of personalized approaches to prevention. Here, we review early life predictors of inter-individual differences in later life neurodevelopment among those born extremely preterm. Among biological mechanisms that mediate relationships between early life predictors and later neurodevelopmental outcomes, we highlight evidence for disrupted placental processes and regulated at least in part via epigenetic mechanisms, as well as perinatal inflammation. In relation to these mechanisms, we focus on four prenatal antecedents of impaired neurodevelopment, namely, (1) fetal growth restriction, (2) maternal obesity, (3) placental microorganisms, and (4) socioeconomic adversity. In the future, this knowledge may inform efforts to detect and prevent adverse outcomes in infants born extremely preterm. IMPACT: This review highlights early life risk factors and mechanisms underlying inter-individual differences in neurodevelopment later in life. The review emphasizes research on early life risk factors (fetal growth restriction, maternal obesity, placental microorganisms, and socioeconomic adversity) and on mechanisms (disrupted placental processes and perinatal inflammation) underlying inter-individual differences in neurodevelopment later in life. The findings highlighted here may inform efforts to detect and prevent adverse outcomes in infants born extremely preterm.

Early life antecedents of positive child health among 10-year-old children born extremely preterm

BACKGROUND

To identify modifiable antecedents during pre-pregnancy and pregnancy windows associated with a positive child health at 10 years of age.

METHODS

Data on 889 children enrolled in the Extremely Low Gestational Age Newborn (ELGAN) study in 2002-2004 were analyzed for associations between potentially modifiable maternal antecedents during pre-pregnancy and pregnancy time windows and a previously described positive child health index (PCHI) score at 10 years of age. Stratification by race was also investigated for associations with investigated antecedents.

RESULTS

Factors associated with higher PCHI (more positive health) included greater gestational age, birth weight, multiple gestation, and medical interventions, including assisted reproduction and cervical cerclage. Factors associated with lower PCHI included correlates of lower socioeconomic status, pre-pregnancy chronic medical disorders in the mother such as pre-pregnancy body mass index (BMI), and maternal asthma. When stratified by race, variation in significant results was observed.

CONCLUSIONS

Among children born extremely preterm, medical interventions and higher socioeconomic status were associated with improved PCHI, while chronic illness and high BMI in the mother is associated with lower PCHI at 10 years of age. Knowledge of such antecedent factors could inform efforts to develop interventions that promote positive child health outcomes in future pregnancies.

Maternal Overweight, Inflammation and Neurological Consequences for the Preterm Child: Results of the ELGAN Study

Maternal overweight and obesity are prenatal risk factors for obstetrical complications, preterm birth, neonatal morbidity as well as cognitive and behavioural developmental disorders in children. Paediatric morbidity and mortality as well as child development disorders are significantly associated with maternal obesity. Particularly in the neurodevelopmental and psychiatric area, it is becoming increasingly clear that, in children of mothers with an increased body mass index (BMI), there is a high correlation with childhood cognitive disabilities, attention disorders, and diseases on the autistic spectrum. The ELGAN (Extremely Low Gestational Age Newborn) study is a multicentre study which has been supported since 2000 by the National Institutes of Health (NIH) and whose objective is to research predictors for neonatal brain damage and neurological-cognitive sequelae in premature infants. The areas of focus are the connection between maternal overweight and obesity and pregnancy complications, APGAR scores and systemic inflammatory markers. In this overview, our aim is to summarise the work in this area and discuss it critically on the basis of current literature. We will examine the hypothesis whether maternal overweight and obesity in terms of a chronic inflammatory state is associated with neonatal inflammation which in turn is associated with an unfavourable development prognosis.

The complex aetiology of cerebral palsy

Cerebral palsy (CP) is the most prevalent, severe and costly motor disability of childhood. Consequently, CP is a public health priority for prevention, but its aetiology has proved complex. In this Review, we summarize the evidence for a decline in the birth prevalence of CP in some high-income nations, describe the epidemiological evidence for risk factors, such as preterm delivery and fetal growth restriction, genetics, pregnancy infection and other exposures, and discuss the success achieved so far in prevention through the use of magnesium sulfate in preterm labour and therapeutic hypothermia for birth-asphyxiated infants. We also consider the complexities of disentangling prenatal and perinatal influences, and of establishing subtypes of the disorder, with a view to accelerating the translation of evidence into the development of strategies for the prevention of CP.