Feeding-Induced Cortisol Response in Newborn Infants

Randomized Controlled Trial on the Effect of the Neonatal Nurse Navigator Program on Maternal Stress and Neonatal Cortisol Levels

OBJECTIVE

To assess the effect of the Neonatal Nurse Navigator Program (NNNP) compared to usual care on maternal stress and neonatal salivary cortisol level (SCL) in the NICU.

DESIGN

Randomized control trial.

SETTING

NICU in a tertiary health care hospital in Manipal, Udupi District, Karnataka, India.

PARTICIPANTS

Neonates between 34 and 36 weeks gestation and their mothers (N = 120 dyads).

METHODS

We used block randomization to assign dyads to the intervention or control group. We measured maternal stress using the Parental Stress Scale: Neonatal Intensive Care Unit, and we estimated neonatal stress by measuring SCLs within 24 hours of NICU admission and before discharge from the unit. We conducted a descriptive analysis on participant characteristics and reported maternal stress levels using means and standard deviations. We used the analysis of covariance change score test to determine the difference in maternal and neonatal stress levels between the intervention and control groups.

RESULTS

The NNNP group exhibited significantly lower maternal stress scores before discharge than the control group, and we observed reductions across all three subscales of the Parental Stress Scale: Neonatal Intensive Care Unit. Mean neonatal salivary cortisol levels were significantly lower in the interventional group than in the control group, F(1.117) = 24.03, 95% confidence interval [7.9, 18.6], p < .001.

CONCLUSION

Use of the NNNP reduced maternal stress SCLs in high-risk neonates by actively engaging mothers in the care of their neonates in the NICU. We recommend adoption of the NNNP model as a standard care policy in NICUs throughout India.

Association of Plasma Cortisol Levels with Gestational Age and Anthropometric Values at Birth in Preterm Infants

There are no study reports to clarify the association between gestational age (GA) or anthropometric values at birth, and plasma cortisol levels in the blood of preterm infants at birth and at one month of age. This hospital-based retrospective cohort study included infants born at <37 weeks' gestation between 2019 and 2021. First, the association between plasma cortisol level and GA or anthropometric values at birth (birth weight standard deviation score [SDS], birth length SDS, and birth head circumference SDS) was identified by regression and multiple regression analyses. Second, plasma cortisol levels in the umbilical cord at birth and at one month of age were compared between small-for-gestational age (SGA) and non-SGA infants. Sixty-one preterm infants were enrolled (SGA: 24 and non-SGA: 37). Plasma cortisol levels at birth were significantly associated with GA. Plasma cortisol levels at one month of age were associated with GA and birth head circumference SDS. Plasma cortisol levels at birth were significantly higher in SGA than non-SGA (p = 0.010). GA was an independent determinant of plasma cortisol levels at birth. SGA infants had a high plasma cortisol level at birth; resulting in speculation that a high plasma cortisol level at birth may predict abnormal neurological outcomes.

Promoting sound development of preterm infants in the name of developmental neuroscience: Beyond advanced life support and neuroprotection

Despite the increased survival opportunities for extremely preterm infants, their long-term cognitive outcomes remain poor, with increased incidence of cognitive impairments in childhood and reduced opportunities to attend higher education in young adulthood compared to their term-born peers. Given that a considerable fraction of preterm infants develop cognitive impairments even without apparent sentinel events at birth and cerebral lesions on MRI assessed at term equivalent age, future strategies to improve the outcome may need to address cerebral dysfunction, which cannot be explained by the classical understanding of the injury cascade triggered by hypoxia-ischaemia around birth. Developmental care has been proposed to minimize neurodevelopmental impairments related to preterm birth. However, considerable modes of cares, environmental settings and procedures provided by the developmental care of current style appear to offer little benefit to the sound development of infants. Although it is obvious that advanced life support and neuroprotective treatments fall far short in compensating for the burden of preterm birth, researchers need to make further effort to fill the knowledge gap in the cerebral function of foetuses and newborn infants before establishing evidence-based developmental care. Clinicians need to develop an ability to translate the findings from basic and translational studies incorporating their potential biases and limitations. Care for newborn infants needs to be reassessed, including but not limited to developmental care, in the context that any sensory input and motor reaction of preterm infants may ultimately affect their cognitive functioning.

Neonatal irritable sleep-wake rhythm as a predictor of autism spectrum disorders

Recently, it has been suggested that sleep problems in autism spectrum disorder (ASD) not only are associated symptoms, but may be deeply related to ASD pathogenesis. Common clinical practice relating to developmental disorders, has shown that parents of children with ASD have often stated that it is more difficult to raise children in the neonatal period because these children exhibit sleep problems. This study investigated the possibility that abnormal neonatal sleep-wake rhythms are related to future ASD development.

We administered questionnaires to assess parent(s) of children with ASD and controls. A retrospective analysis was conducted among 121 children with ASD (94 male and 27 female children) recruited from the K-Development Support Center for Children (K-ASD), 56 children with ASD (40 male and 16 female children) recruited from the H-Children's Sleep and Development Medical Research Center (H-ASD) and 203 children (104 male and 99 female children) recruited from four nursery schools in T-city (control).

Irritable/over-reactive types of sleep-wake rhythms that cause difficulty in raising children, such as 1) frequently waking up, 2) difficulty falling asleep, 3) short sleep hours, and 4) continuous crying and grumpiness, were observed more often in ASD groups than in the control group. Additionally, the number of the mothers who went to bed after midnight during pregnancy was higher in the ASD groups than in the control group.

Sleep-wake rhythm abnormalities in neonates may be considerable precursors to future development of ASD. Formation of ultradian and postnatal circadian rhythms should be given more attention when considering ASD development. Although this is a retrospective study, the results suggest that a prospective study regarding this issue may be important in understanding and discovering intervention areas that may contribute to preventing and/or properly treating ASD.

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Neonatal irritable-type sleep-wake rhythmabnormalities are important precursors for futureASD development.

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Maternal lack of sleep and irregular lifestyle isrelated to increased risk of possibly developingfuture ASD.

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There is a possibility that proper intervention toabnormal sleep-wake rhythm may prevent thesubsequent onset of ASD.

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It is more logical to understand and interpret ASD,based on circadian rhythm and pineal glandfunction.

Intrauterine growth and the maturation process of adrenal function

Backgrounds

Environmental factors during early life alter the hypothalamus-pituitary-adrenal (HPA) axis regulation and increase the risk of diseases in later life. However, adrenal function at each developmental stage has not fully been investigated in relation to pathological antenatal conditions. Cortisol levels of newborns with intrauterine growth restriction (IUGR) are elevated during the neonatal period; however, when studied during early childhood, cortisol levels are reduced compared with their peers, suggesting that the HPA axis regulation might be altered from activation to suppression, the timing of which remains uncertain.

Aim

The aim of this study was to assess the presence of an interaction between intrauterine growth and postnatal age on cortisol levels in newborns hospitalised at a neonatal intensive care unit.

Methods

We performed a secondary analysis using a dataset from saliva samples of 62 newborns collected between 30 and 40 weeks corrected age. Interactions between postnatal age and clinical variables with regard to cortisol levels were assessed.

Results

The z-score of the birth weight and IUGR showed significant interactions with postnatal age on cortisol levels; cortisol levels were higher ≤5 days of birth and lower >14 days of birth than those in their peers without IUGR.

Conclusion

The adrenal function of newborns with IUGR might be altered from activation to suppression within the first several weeks of life. Longitudinal studies need to address when/how IUGR alters adrenal functions, and how these responses are associated with diseases during adulthood.