Scoping Review of Early Toxic Stress and Epigenetic Alterations in the Neonatal Intensive Care Unit

Early Life Stress, DNA Methylation of NR3C1 and HSD11B2 , and Oral Feeding Skill Development in Preterm Infants : A Pilot Study

BACKGROUND

Early life stress exposure in preterm infants may alter DNA methylation of NR3C1 and HSD11B2 , disrupting neurobehaviors needed for oral feeding (PO) skill development.

PURPOSE

To (1) examine the feasibility of the study protocol; (2) describe early life stress, DNA methylation of NR3C1 and HSD11B2 , and PO skill development; and (3) explore the association between DNA methylation of NR3C1 and HSD11B2 and infant characteristics, early life stress, and PO skill development.

METHOD

We employed a longitudinal descriptive pilot study (N = 10). Infant characteristics were collected from the infant's electronic medical record. Early life stress was assessed via the modified Neonatal Infant Stressor Scale. DNA methylation of NR3C1 exon 1F and HSD11B2 promoter regions was analyzed from the infant's buccal samples. PO skill development was evaluated using the Early Feeding Skills Assessment.

RESULTS

Infants who experienced more acute and chronic stress during their neonatal intensive care unit hospitalization demonstrated higher DNA methylation at CpG 17 and 31 of the NR3C1 exon 1F and at CpG 4 and 28 of the HSD11B2 promoter regions. Infants with higher DNA methylation at these CpG sites also exhibited less optimal PO skill development and experienced longer transition from first to full PO.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Our findings revealed relationships among early life stress, DNA methylation of NR3C1 and HSD11B2 , and PO skill development in preterm infants. Future research is warranted to examine the multiomics pathways whereby early life stress influences the phenotypes of infant outcomes.

Validity and use of the Neonatal Infant Stressor Scale: An integrative review

BACKGROUND

Stress exposure, operationalized as a count of painful or skin-breaking breaking procedures, is an important concept for inclusion in studies of preterm infants. The Neonatal Infant Stressor Scale (NISS) was developed to also account for nonpainful and environmental stressors; however, validity of this measure is unknown.

AIMS

The purpose of this review was to define the breadth of use of the NISS in neonatal research studies and determine its predictive and concurrent validity.

METHODS

Using the methods for integrative review, a systematic search of the literature was conducted using PubMed, CINAHL, PsycINFO, and Embase with keywords "NISS" OR "Neonatal Infant Stressor Scale". Study findings were narratively synthesized.

RESULTS

Twenty-nine articles were retained for the review and included two cross-sectional studies describing development or adaptation of the measure, two protocols for empirical studies, and 25 empirical studies of preterm infants. Modifications to the original NISS were common and included addition or exclusion of specific stressors and use of unweighted scores. Although findings were inconsistent across studies, limited data support the predictive validity of the NISS, as higher NISS scores have been associated with abnormal brain development and cognitive, motor, and behavioral deficits. Two studies found concurrent associations between NISS scores and cortisol.

CONCLUSION

The NISS may be a useful tool to quantify stressors experienced by preterm infants; however, there are only limited data to support its predictive or concurrent validity. The NISS may be particularly useful as a method to bring awareness to the infant's stress burden in clinical practice. Additional research is needed to validate inclusion of specific stressors in the NISS.

Genetic association of SLC6A3 (dopamine transporter) gene polymorphisms with personality disorders and substance abuse disorders: a systematic review and meta-analysis

INTRODUCTION

Personality disorders (PD) are characterized by socially dysfunctional behavioral patterns that affect patients and show higher incidence rates within families. Substance abuse disorders (SAD) are exemplified by extensive and prolonged use of substances, including alcohol, nicotine, or illegal drugs. Genetic predisposition for both PD and SAD has been reported to involve gene variants regulating dopaminergic pathways. Yet, discrepancy among reported results necessitates further elucidation of potential hereditary-related risk factors. Because both disorders impose a societal burden, knowledge on the impact of certain genetic backgrounds on these diseases could help develop evidence-based strategies for efficacious treatment approaches.

MATERIALS AND METHODS

In the present study a systematic review was performed, and the association between dopamine transporter gene polymorphism (SLC6A3), particularly rs28363170 entailing a 40-bp variable number tandem repeat, and PD as well as SAD was investigated recruiting meta-analysis approach.

RESULTS

Initial literature search for PD yielded 1577, from which nine fulfilled eligibility criteria to be used in a meta-analysis including 729 cases and 2113 controls. From the 934 studies retrieved for SAD, only 29 articles with 5221 cases and 4822 controls were used for meta-analysis. A statistically significant association was seen between rs28363170 (for the 9-repeat allele) and PD in European populations according to the co-dominant mode of inheritance. For SAD no statistically significant correlation under any mode of inheritance was observed. There was no indication of time-trend phenomena.

CONCLUSION

Our findings demonstrate the association of SLC6A3 gene polymorphism with PD, thus underling the need to understand neurobiological mechanisms inherent to the above disorders to guide treatment strategies under the perspective of personalized medicine.

Multiple Attempts of Peripheral Intravenous Catheter Insertion in a Preterm Infant Provoke Toxic Stress: A Case Report

Premature infants admitted to the NICU often require intravenous (IV) therapy. Peripheral intravenous catheter (PIVC) insertion is a common painful/stressful/invasive procedure. Repeated exposure to stressors produces toxic stress: a prolonged, frequent activation of the body's stress response that occurs when buffering relationships, that is, mother/supportive adult, are absent. This article presents an exemplar case study of a PIVC insertion to describe toxic stress responses a premature infant experienced during the procedure. The infant was admitted for extreme prematurity and respiratory failure. Twenty-nine days later, the infant developed possible necrotizing enterocolitis that necessitated cessation of enteral feedings, gastric decompression, IV administration of fluids, parenteral nutrients, and antibiotics. The PIVC insertion procedure was monitored and observed. The infant showed physiologic dysregulation, including bradycardia, tachycardia, oxygen desaturation, and high skin conductance responses, resulting from the stress exposure and insufficient nonpharmacologic/pharmacologic stress interventions. Education and practice change are needed to promote pain/stress management.

Early life epigenetics and childhood outcomes: a scoping review

Epigenetics is the study of changes in gene expression, without a change in the DNA sequence that are potentially heritable. Epigenetic mechanisms such as DNA methylation, histone modifications, and small non-coding RNA (sncRNA) changes have been studied in various childhood disorders. Causal links to maternal health and toxin exposures can introduce epigenetic modifications to the fetal DNA, which can be detected in the cord blood. Cord blood epigenetic modifications provide evidence of in-utero stressors and immediate postnatal changes, which can impact both short and long-term outcomes in children. The mechanisms of these epigenetic changes can be leveraged for prevention, early detection, and intervention, and to discover novel therapeutic modalities in childhood diseases. We report a scoping review of early life epigenetics, the influence of maternal health, maternal toxin, and drug exposures on the fetus, and its impact on perinatal, neonatal, and childhood outcomes. IMPACT STATEMENT: Epigenetic changes such as DNA methylation, histone modification, and non-coding RNA have been implicated in the pathophysiology of various disease processes. The fundamental changes to an offspring's epigenome can begin in utero, impacting the immediate postnatal period, childhood, adolescence, and adulthood. This scoping review summarizes current literature on the impact of early life epigenetics, especially DNA methylation on childhood health outcomes.

Predictive role of NICU-related stress, postpartum depression trajectory and family coping on growth trajectory of moderate-to-late preterm infants: A longitudinal study

AIMS

To describe the changes in moderate-to-late preterm infants' (MLPIs) growth during 12 months of corrected age (CA) and to examine the predictive role of NICU-related stress, postpartum depression trajectory and family coping ability on the physical developmental trajectory of MLPIs.

DESIGN

A prospective longitudinal study.

METHODS

There were 237 mother-infant dyads with at least two follow-up data records included. General characteristics and NICU-related stress were recorded from medical records at baseline. Infants' physical growth was measured at 40 weeks, 1, 3, 6, 9 and 12 months CA during outpatient follow-up. Maternal postpartum depressive symptoms and family coping ability were assessed by questionnaires at 1, 3, 6, 9 and 12 months CA and 1 month CA respectively. We investigated the modifiable factors inside and outside of NICU on the trajectories of physical growth in the first year in MLPIs, mainly by using latent growth curve models with time-varying covariates.

RESULTS

The curved trajectories of weight, length and head circumference in the first year in MLPIs demonstrated gradually slowed growth rates and these infants were above the WHO growth standards for the same age and sex. The latent growth curve models indicated that more NICU-related stress was negatively associated with the weight and length at 40 weeks CA, and family coping ability (parent-child relationship) at 1 month CA was associated with the growth rate of weight. Besides, more NICU-related stress predicted faster length growth rate. The infants of mothers who were in the group of high-level postpartum depression trajectory had a slower growth rate of head circumference.

CONCLUSIONS

Our study identified the modifiable factors along the care continuum influencing the trajectory of MLPIs' physical growth. Nurses should receive more training about infant stress measurement and family-centred care to work in partnership with parents so that MLPIs can reach their full developmental potential. Also, multidisciplinary interventions including stress reduction strategies, close psychological monitoring and education improving parent-infant relationships should be further developed to achieve optimizing growth in the first year of MLPIs.

IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE

It is recommended that nurses pay attention to the long-term physical growth status of MLPIs, and closely support their families. Quantifying NICU-related stress and developing reduction strategies should be the priority for clinical staff during hospitalization. After discharge, persistent screening of depressive symptoms, psychological intervention and education about the parent-child relationship need to be included in the follow-up visits.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution. The study only included patients who were research participants.

Comparing conventional and modified Seldinger techniques using a micro-insertion kit for PICC placement in neonates: a retrospective cohort study

Objective

This study aims to assess the comparative effectiveness of a conventional splitting needle or a peelable cannula vs. the modified Seldinger technique (MST) by utilizing a dedicated micro-insertion kit across various clinically significant metrics, including insertion success, complications, and catheter-related infections.

Methods

We conducted a retrospective observational cohort study using an anonymized data set spanning 3 years (2017-2019) in a large tertiary-level neonatal intensive care unit in Qatar.

Results

A total of 1,445 peripherally inserted central catheter (PICC) insertion procedures were included in the analysis, of which 1,285 (89%) were successful. The primary indication for insertion was mainly determined by the planned therapy duration, with the saphenous vein being the most frequently selected blood vessel. The patients exposed to MST were generally younger (7 ± 15 days vs. 11 ± 26 days), but exhibited similar mean weights and gestational ages. Although not statistically significant, the MST demonstrated slightly higher overall and first-attempt insertion success rates compared to conventional methods (91 vs. 88%). However, patients undergoing conventional insertion techniques experienced a greater incidence of catheter-related complications (p < 0.001). There were 39 cases of catheter-related bloodstream infections (CLABSI) in the conventional group (3.45/1,000 catheter days) and eight cases in the MST group (1.06/1,000 catheter days), indicating a statistically significant difference (p < 0.001). Throughout the study period, there was a noticeable shift toward the utilization of the MST kit for PICC insertions.

Conclusion

The study underscores the viability of MST facilitated by an all-in-one micro kit for neonatal PICC insertion. Utilized by adept and trained inserters, this approach is associated with improved first-attempt success rates, decreased catheter-related complications, and fewer incidences of CLABSI. However, while these findings are promising, it is imperative to recognize potential confounding factors. Therefore, additional prospective multicenter studies are recommended to substantiate these results and ascertain the comprehensive benefits of employing the all-in-one kit.

Effect of music-based interventions on physiologic stability of hospitalized preterm infants. A pilot study

BACKGROUND AND OBJECTIVE

Hospitalized preterm infants experience reduced meaningful auditory exposures during a critical period of brain development. Music-based interventions (MBI) may be beneficial, though it remains unclear which stimuli optimally enhance infant stabilization. We investigated the relationship between three conceptually-different MBIs and short-term responses in hospitalized preterm infants.

STUDY DESIGN

This is a case-crossover pilot study including 21 preterm infants between 30 and 35 weeks postmenstrual age. Participants listened to three MBIs and 'no music'; each condition was provided three times in random order. We monitored physiologic and behavioral parameters around each exposure and analyzed results using linear mixed models.

RESULTS

Respiratory rates decreased after each MBI compared with 'no music' (p = 0.02). The most notable decrease occurred following exposure to a low, repetitive musical pattern resembling a lullaby (p = 0.01). We noted no significant changes for the remaining parameters.

CONCLUSION

Specific MBI characteristics may preferentially enhance physiologic stabilization in hospitalized preterm infants.

Feasibility of Stress Research in Premature Infant-Maternal Dyads During and After Neonatal Intensive Care Unit Hospitalization

BACKGROUND

Stress from preterm infant admission to the neonatal intensive care unit (NICU) is associated with infant and maternal physiologic changes, including endocrine and epigenetic alterations. Little is known about the mechanisms connecting NICU stress to biologic changes, and whether preterm infant and maternal stress are reciprocal. As a preliminary step, feasibility and acceptability of measuring indicators of stress are required.

PURPOSE

This study evaluated the feasibility and acceptability of research examining perceptions and biologic markers of stress in premature infant-maternal dyads during and after NICU hospitalization.

METHODS

We evaluated study feasibility using a longitudinal descriptive design. Acceptability was measured via a maternal questionnaire. Exploratory data regarding hospitalization, perceptions of stress, social support and social determinants of health, and biologic markers of stress were collected during the first week of life and again 3 months after NICU.

RESULTS

Forty-eight mothers were eligible for the study, 36 mothers were approached, 20 mothers consented to participate, and 14 mothers completed data collection. Mothers reported high levels of study acceptability despite also voicing concern about the sharing of genetic data. Exploration of DNA methylation of SLC6A4 in preterm infants was significant for a strong correlation with perception of total chronic stress.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Clinical practice at the bedside in the NICU should include standardized screening for and early interventions to minimize stress. Complex research of stress is feasible and acceptable. Future research should focus on linking early life stress with epigenetic alterations and evaluation of the dyad for reciprocity.