17-year outcome of preterm infants with diverse neonatal morbidities: Part 1--Impact on physical, neurological, and psychological health status

A Systematic Review and Meta-analysis of Prenatal, Birth, and Postnatal Factors Associated with Attention-Deficit/Hyperactivity Disorder in Children

Previous studies have shown mixed results on the relationship between prenatal, birth, and postnatal ("pregnancy-related") risk factors and attention-deficit/hyperactivity disorder (ADHD). We conducted meta-analyses to identify potentially modifiable pregnancy-related factors associated with ADHD. A comprehensive search of PubMed, Web of Science, and EMBASE in 2014, followed by an updated search in January 2021, identified 69 articles published in English on pregnancy-related risk factors and ADHD for inclusion. Risk factors were included in the meta-analysis if at least three effect sizes with clear pregnancy-related risk factor exposure were identified. Pooled effect sizes were calculated for ADHD overall, ADHD diagnosis, inattention, and hyperactivity/impulsivity. Odds ratios (OR) were calculated for dichotomous measures and correlation coefficients (CC) for continuous measures. Prenatal factors (pre-pregnancy weight, preeclampsia, pregnancy complications, elevated testosterone exposure), and postnatal factors (Apgar score, neonatal illness, no breastfeeding) were positively associated with ADHD overall; the findings for ADHD diagnosis were similar with the exception that there were too few effect sizes available to examine pre-pregnancy weight and lack of breastfeeding. Prenatal testosterone was significantly associated with inattention and hyperactivity/impulsivity. Effect sizes were generally small (range 1.1-1.6 ORs, -0.16-0.11 CCs). Risk factors occurring at the time of birth (perinatal asphyxia, labor complications, mode of delivery) were not significantly associated with ADHD. A better understanding of factors that are consistently associated with ADHD may inform future prevention strategies. The findings reported here suggest that prenatal and postnatal factors may serve as potential targets for preventing or mitigating the symptoms of ADHD.

Small for gestational age preterm infants and later adiposity and height: A systematic review and meta-analysis

BACKGROUND

Overweight and obesity and their consequent morbidities are important worldwide health problems. Some research suggests excess adiposity origins may begin in fetal life, but unknown is whether this applies to infants born preterm.

OBJECTIVE

The objective of the study was to assess the association between small for gestational age (SGA) birth and later adiposity and height among those born preterm.

DATA SOURCES

MEDLINE, EMBASE and CINAHL until October 2022.

STUDY SELECTION AND DATA EXTRACTION

Studies were included if they reported anthropometric (adiposity measures and height) outcomes for participants born preterm with SGA versus non-SGA. Screening, data extraction and risks of bias assessments were conducted in duplicate by two reviewers.

SYNTHESIS

We meta-analysed across studies using random-effects models and explored potential heterogeneity sources.

RESULTS

Thirty-nine studies met the inclusion criteria. In later life, preterm SGA infants had a lower body mass index (-0.66 kg/m2 , 95% CI -0.79, -0.53; 32 studies, I2  = 16.7, n = 30,346), waist circumference (-1.20 cm, 95% CI -2.17, -0.23; 13 studies, I2  = 19.4, n = 2061), lean mass (-2.62 kg, 95% CI -3.45, 1.80; 7 studies, I2  = 0, n = 205) and height (-3.85 cm, 95% CI -4.73, -2.96; 26 studies, I2  = 52.6, n = 4174) compared with those preterm infants born non-SGA. There were no differences between preterm SGA and preterm non-SGA groups in waist/hip ratio, body fat, body fat per cent, truncal fat per cent, fat mass index or lean mass index, although power was limited for some analyses. Studies were rated at high risk of bias due to potential residual confounding and low risk of bias in other domains.

CONCLUSIONS

Compared to their preterm non-SGA peers, preterm infants born SGA have lower BMI, waist circumference, lean body mass and height in later life. No differences in adiposity were observed between SGA preterm infants and non-SGA preterm infants.

Preterm Birth, Developmental Smoke/Nicotine Exposure, and Life-Long Pulmonary Sequelae

This review delineates the main pulmonary issues related to preterm birth, perinatal tobacco/nicotine exposure, and its effects on offspring, focusing on respiratory health and its possible transmission to subsequent generations. We review the extent of the problem of preterm birth, prematurity-related pulmonary effects, and the associated increased risk of asthma later in life. We then review the impact of developmental tobacco/nicotine exposure on offspring asthma and the significance of transgenerational pulmonary effects following perinatal tobacco/nicotine exposure, possibly via its effects on germline epigenetics.

Safer Baby Bundle: study protocol for the economic evaluation of a quality improvement initiative to reduce stillbirths

INTRODUCTION

Stillbirth continues to be a public health concern in high-income countries, and with mixed results from several stillbirth prevention interventions worldwide the need for an effective prevention method is ever present. The Safer Baby Bundle (SBB) proposes five evidence-based care packages shown to reduce stillbirth when implemented individually, and therefore are anticipated to produce significantly better outcomes if grouped together. This protocol describes the planned economic evaluation of the SBB quality improvement initiative in Australia.

METHODS AND ANALYSIS

The implementation of the SBB will occur over three state-based health jurisdictions in Australia-New South Wales, Queensland and Victoria, from July 2019 onwards. The intervention is being applied at the state level, with sites opting to participate or not, and no individual woman recruitment. The economic evaluation will be based on a whole-of-population linked administrative dataset, which will include the data of all mothers, and their resultant children, who gave birth between 1 January 2016 and 31 December 2023 in these states, covering the preimplementation and postimplementation time period. The primary health outcome for this economic evaluation is late gestation stillbirths, with the secondary outcomes including but not limited to neonatal death, gestation at birth, mode of birth, admission to special care nursery and neonatal intensive care unit, and physical and mental health conditions for mother and child. Costs associated with all healthcare use from birth to 5 years post partum will be included for all women and children. A cost-effectiveness analysis will be undertaken using a difference-in-difference analysis approach to compare the primary outcome (late gestation stillbirth) and total costs for women before and after the implementation of the bundle.

ETHICS AND DISSEMINATION

Ethics approval for the SBB project was provided by the Royal Brisbane & Women's Hospital Human Research Ethics Committee (approval number: HREC/2019/QRBW/47709). Approval for the extraction of data to be used for the economic evaluation was granted by the New South Wales Population and Health Services Research Ethics Committee (approval number: 2020/ETH00684/2020.11), Australian Institute of Health and Welfare Human Research Ethics Committee (approval number: EO2020/4/1167), and Public Health Approval (approval number: PHA 20.00684) was also granted. Dissemination will occur via publication in peer reviewed journals, presentation at clinical and policy-focused conferences and meetings, and through the authors' clinical and policy networks.This study will provide evidence around the cost effectiveness of a quality improvement initiative to prevent stillbirth, identifying the impact on health service use during pregnancy and long-term health service use of children.

Sensory stimulation program improves developments of preterm infants in Southwest China: A randomized controlled trial

Preterm infants are prone to growth and developmental delay, especially social-emotional development. Sensory stimulation may benefit developmental outcomes for these vulnerable infants. This study aims to determine whether 5-integrated sensory stimulation (5-ISS) improves preterm infant social-emotional development. A randomized, parallel trial was conducted from November 2018 to January 2020 at three tertiary hospitals in Kunming, China. Preterm infants were eligible if gestational ages were from 28 to 36 weeks based on ultrasound results when discharged from neonatal wards. Two hundred preterm infants (male n = 110, female n = 90) were randomly allocated to the 5-ISS intervention group (n = 98) and the standard care group (n = 102). Social-emotional development was assessed with the Ages and Stages Questionnaires: Social-Emotional (ASQ:SE). Temperament was assessed with the Infant Behavior Questionnaire-Revised. Anthropometry, which included weight, length, and head circumference, was measured at corrected ages of 1, 3, and 6 months. Demographic and clinical characteristics were similar between the intervention and the standard care groups. At 1- and 3-month corrected age, no significant differences between the two groups were observed in terms of infant development and temperament. At 6 months, significant disparities were found in the social-emotional development scale (mean difference −0.29, 95% CI: −0.58, < -0.001, p = 0.01), infant length (mean difference 0.70, 95% CI: < 0.001, 1.4, p = 0.03), distress to limitation (p = 0.04), and sadness (p = 0.03). A mixed model revealed that the 5-ISS intervention positively affected social-emotional development, length, distress to limitation, and sadness for preterm infants. Integrated sensory stimulation has benefits on social-emotional development, temperament, and length for preterm infants. This program provides a feasible method to promote social-emotional development for preterm infants.

Health Economics and Equity in Preconception Health Care: A Systematic Review

Poor pregnancy outcomes affect a child's lifelong health and disadvantaged populations are at higher risk of poor pregnancy outcomes. Preconception care aims to improve pregnancy outcomes by managing conditions and risks prior to conception. Given known inequities in pregnancy outcomes, the adoption of preconception care may benefit disadvantaged populations. Health economics plays an important role in the implementation of interventions, as economic evaluations seek to identify the most efficient and equitable care options. This review aimed to identify the cost-effectiveness of preconception care and how equity has been considered in these evaluations. A systematic review of literature published between 2012-2022 was undertaken to identify studies that evaluate the economic outcomes of preconception care. Studies that met the inclusion criteria were manually searched for consideration of equity in the economic evaluation analysis. Costs were presented and a narrative synthesis of studies reporting on outcomes of equity was conducted. Eight studies met the inclusion criteria, and only two reported on aspects of equity, specifically ethnicity. Considering the significant disparities in pregnancy outcomes among disadvantaged populations, aspects of equity are important to consider when implementing and evaluating preconception interventions. Therefore, it is recommended that future research focuses on the cost-effectiveness of preconception care and that these evaluations incorporate aspects of equity.

Molding influences of prematurity: Interviews with adults born preterm

BACKGROUND

Tremendous medical advancements over the last several decades have supported the survival of younger and sicker newborns. Substantial quantitative research exists about health and developmental outcomes following preterm birth, however, limited published literature has explored what this experience means to the survivors.

AIM

The purpose was to describe, interpret and understand how adults born preterm perceive prematurity to have affected their lives.

STUDY DESIGN

Qualitative thematic analysis.

METHODS

Semi-structured interviews were conducted with 33 adults born preterm from the RHODĒ Study, a longitudinal preterm birth cohort. A cross-section of participants with high and low early life medical and environmental risk was interviewed. Data were analyzed using a constructionist method of latent theme analysis.

RESULTS

From the data, 3 themes were identified: 1) My parents call me their miracle, 2) It's not a big deal, I'm the same as everyone else, 3) I've overcome a lot. Themes represent a continuum of experience, from positive to neutral to negative. Common life experiences of family, education, friends, and health are subthemes that help to illuminate how participants assign meaning to their prematurity. Meaning was linked to how typical or not participants perceive their health, learning and friends compared to peers.

CONCLUSION

Perceptions about prematurity and adversity are influenced by the ways parents and families represent prematurity in shared stories and actions. These findings should inform future research with adult survivors of prematurity. Participants identified ongoing need for support and advocacy, particularly from healthcare and education communities.

Understanding early-life pain and its effects on adult human and animal emotionality: Translational lessons from rodent and zebrafish models

Critical for organismal survival, pain evokes strong physiological and behavioral responses in various sentient species. Clinical and preclinical (animal) studies markedly increase our understanding of biological consequences of developmental (early-life) adversity, as well as acute and chronic pain. However, the long-term effects of early-life pain exposure on human and animal emotional responses remain poorly understood. Here, we discuss experimental models of nociception in rodents and zebrafish, and summarize mounting evidence of the role of early-life pain in shaping emotional traits later in life. We also call for further development of animal models to probe the impact of early-life pain exposure on behavioral traits, brain disorders and novel therapeutic treatments.

Self-Recognition and Emotional Knowledge

Self-recognition emerges during the second year of life and represents the emergence of a reflective self, a metacognition which underlies self-conscious emotions such as embarrassment and shame, perspective taking, and emotional knowledge of others. In a longitudinal study of 171 children, two major questions were explored from an extant database: 1) Do early factors, including IQ, general environmental risk, mother-child attachment interaction, drug exposure, gender, and neonatal risk, relate to self-recognition?; 2) Does self-recognition, along with these earlier factors, predict the child's subsequent emotional knowledge? Consistent with previous data, 39% of children exhibited self-recognition by 18-months and few early factors explored were related to this ability. Moreover, path analysis revealed few effects of the earlier factors predicting self-recognition on children's emotional knowledge. Self-recognition did predict emotional knowledge at 4.5 years, such that children who showed early self-recognition showed greater emotional knowledge. Children from high risk environments also showed lower emotional knowledge. These findings indicate that self-recognition and environmental risk are related to children's later knowledge of emotions.

Using epidemiological and health economic measures to inform maternity staffing decisions: A guide

BACKGROUND

There is growing concern around unnecessary intervention (particularly caesarean section) at birth in high-income countries. Caseload midwifery care aims to offset this, but is perceived to be costly to health services.

AIM

To use epidemiological and health economic techniques to estimate health outcomes and cost-savings of different levels of equivalent full time (EFT) midwives working in caseload midwifery care.

METHODS

Two simulations were conducted - one assuming 10 EFT midwives working in a caseload model, with 35 women per caseload, and one assuming 50 EFT midwives working in a caseload model, with 45 women per caseload. Both were based on a sample of 5000 women. The main model inputs included rates of health outcomes for women (caesarean section, epidural anaesthesia, and episiotomy) and infants (low birthweight and admissions to special care nursery (SCN) or neonatal intensive care unit (NICU)), and the cost savings associated with health outcome avoidance.

FINDINGS

The first simulation estimated 27 fewer caesarean sections, 12 fewer epidurals, 12 fewer episiotomies, 10 fewer low birthweight births, and 23 fewer infants admitted to SCN or NICU annually, at a total cost saving of AU$1,874,715. The second simulation estimated 173 fewer caesarean sections, 76 fewer epidurals, 76 fewer episiotomies, 65 fewer low birthweight births, and 150 fewer infants admitted to SCN or NICU annually, at a total cost saving of AU$12,051,741.

CONCLUSION

This study provides local-level decision-makers with a decision-tool to calculate the potentially avoidable health outcomes and cost savings associated with implementing caseload midwifery care in their own service.

Next generation strategies for preventing preterm birth

Preterm birth (PTB) is defined as delivery before 37 weeks of gestation. Globally, 15 million infants are born prematurely, putting these children at an increased risk of mortality and lifelong health challenges. Currently in the U.S., there is only one FDA approved therapy for the prevention of preterm birth. Makena is an intramuscular progestin injection given to women who have experienced a premature delivery in the past. Recently, however, Makena failed a confirmatory trial, resulting the Center for Drug Evaluation and Research's (CDER) recommendation for the FDA to withdrawal Makena's approval. This recommendation would leave clinicians with no therapeutic options for preventing PTB. Here, we outline recent interdisciplinary efforts involving physicians, pharmacologists, biologists, chemists, and engineers to understand risk factors associated with PTB, to define mechanisms that contribute to PTB, and to develop next generation therapies for preventing PTB. These advances have the potential to better identify women at risk for PTB, prevent the onset of premature labor, and, ultimately, save infant lives.

Late adolescent & young adult functioning and participation outcomes after prematurity

There has been an increased emphasis on optimizing health, developmental, and behavioral outcomes over the life course after prematurity. An important framework for examining adolescent and young adult outcomes is the International Classification of Functioning Disability and Health Children (ICF) developed by the World Health Organization (WHO) in 2001 and expanded to children and youth (ICF-CY) under age 19 years in 2007. The ICF and the ICF-CY can be used as a statistical tool in population studies, a research tool to measure outcomes, quality of life, and environmental factors, a clinical tool for outcomes of rehabilitation and vocation training, and as a social policy-educational tool to raise awareness and promote social action for equity. In this review we describe how functioning and participation can help inform transitional outcomes at age 17 years and emerging adult independence at 23 years. We highlight outcomes in adolescence and adulthood of former preterm infants using the ICF domains of functioning and participation. We include current standardized adaptive assessments (Vineland Adaptive Behavior Scales-3rd Edition; VABS3) and Adaptive Behavior Assessment Scale-3; ABAS3) that measure self-care daily living skills, applied learning, and social functioning. We also emphasize that participation involves life activities of higher education attainment, completing vocational training, experiencing employment, living independently, and relationship experiences with partners as well as family formation.

The experiences of mothers with preterm infants within the first-year post discharge from NICU: social support, attachment and level of depressive symptoms

BACKGROUND

The estimated global premature birth rate for 2014 was 10.6%, equating to an estimate of 14.84 million live premature births. The experience of premature birth does not impact solely on the infant and mother as individuals but occurs in the context of a critical point in time when they are developing a relationship with one another. The aim of this study was to investigate the relationships between social support, mother to infant attachment, and depressive symptoms of mothers with preterm infants within the first 12 months' post discharge from the Neonatal Intensive Care Unit (NICU).

METHODS

A correlational cross-sectional study design was used. Data were collected using a four-part online survey which included the Perinatal Social Support Questionnaire (PICSS), Maternal Postnatal Attachment Scale (MPAS) and the Edinburgh Postnatal Depression Scale (EPDS) with mothers of preterm infants (n = 140).

RESULTS

The prevalence of postnatal depression was 37.9% (95% CI: 29.8 to 46.4%). In univariable analyses, history of depression (p = 0.005), aged 35-39 years (p = 0.006), no formal social support (p = 0.040), less informal social supports (p = 0.018), lower overall maternal attachment (p < 0.001) and lower overall functional social support (p < 0.001) were significantly associated with a higher level of depressive symptoms. Lower scores on two of the maternal attachment subscales (quality of attachment and absence of hostility) and all four of the functional social support subscales were significantly associated with a higher level of depressive symptoms (p < 0.001 for all). In the multivariable analysis, prior history of depression (p = 0.028), lower score of maternal attachment (p < 0.001) and lower emotional functional social support (p = 0.030) were significantly associated with a higher level of depressive symptoms.

CONCLUSION

Women who experience a premature birth, have a prior history of depression, poor infant attachment and poor emotional social support have a higher level of depressive symptoms. Results emphasise the need for professionals to encourage mobilisation of maternal formal and informal social supports. It is important to intervene early to address maternal emotional well-being and enhance the developing mother-preterm infant relationship.

The Effect of Donor Human Milk Fortification on The Adhesion of Probiotics In Vitro

Preterm delivery complications are the primary cause of death among children under the age of five. Preventive strategies include the use of pasteurized donor human milk (DHM), its fortification with human milk fortifiers (protein supplements), and supplementation with probiotics. Our aim was to examine the impact of DHM and fortified DHM (FDHM) on the mucus adhesion properties of two widely used probiotics. The study covered two forms of human milk fortifier, liquid and powdered, with or without probiotics and storage at 4 °C for 24 h. To test the adhesion properties of the probiotic strains, DHM+probiotics and FDHM+probiotics were prepared and added to immobilized mucus isolated from the stool of healthy Finnish infants. The probiotic adhesion was then measured by liquid scintillation. Our results suggest that addition of liquid or powdered human milk fortifier in donor human milk had no impact on probiotic adhesion. In addition, given the increased adhesion of probiotics suspended in buffer, other matrices should be further studied. These factors need to be considered when designing future intervention strategies using probiotics in preterm infants.

Novel method of measuring chronic stress for preterm infants: Skin cortisol

BACKGROUND AND OBJECTIVES

Infants who begin life in the medicalized environment of the neonatal intensive care unit (NICU) do so under stressful conditions. Environmental exposures are often abrasive to vulnerable infants, while invasive and noninvasive lifesaving interventions provide additional pain and/or stress. The most commonly selected biomarker to measure stress is cortisol. The skin is the barrier between the external environment and communicates with our neurological, endocrine and immune regulatory networks. To examine if skin cortisol may be a reliable biomarker of stress, NICU stress exposure and repeated measurements of skin cortisol in very preterm infants were examined retrospectively during the first 6 weeks of life. The temporal relationship between skin cortisol and NICU stress exposure was also analyzed.

MATERIALS AND METHODS

Participants included 82 preterm infants born weighing less than 1500 g, admitted to a level III NICU, with a mean gestational age of 28.5 weeks. Infants were studied from birth through 6 weeks of life. NICU stress data was collected using the Neonatal Infant Stressor Scale. Skin samples were collected using d-squame tape as soon after birth as possible and every two weeks thereafter.

RESULTS

On average, infants experienced approximately 43 stressful events per day during the first 6 weeks of life in the NICU. Stress level and cortisol reactivity varied by gestation age. Higher stress resulted in higher cortisol for infant >28 weeks; lower stress scores were associated with higher stress for infants <28 weeks. Stress exposure during 7 days prior to cortisol sampling yielded the highest AUC for the 2 groups. A statistically significant interaction was identified between gestational age and stress exposure during the previous 7 days (p < 0.01).

CONCLUSION

This is the first study to demonstrate skin cortisol as a preterm infant biomarker of chronic stress exposure. For infants with appropriate skin maturation, this non-invasive sampling method provides several benefits. Importantly, this method may be less intrusive and disruptive for preterm infants.

A Meta-Analysis of the Association Between Birth Weight and Attention Deficit Hyperactivity Disorder

A large body of work has investigated the association between birth weight and ADHD and has resulted in mixed findings with regard to the direction and magnitude of this association. Despite the vast amount of research on this topic, a comprehensive and systematic quantification of the association between birth weight and ADHD has yet to be undertaken. A meta-analysis of 88 unique studies (N = 4,645,482) was conducted to quantify the overall effect size of birth weight on ADHD symptoms. Several variables were examined as moderators that may contribute to systematic variation in effect sizes. Overall, birth weight was found to have a small, but significant, association with ADHD symptoms such that individuals born at lower birth weights manifested greater symptoms of ADHD (r = -0.15). Sample type, mean birth weight of the sample, geographic region, the informant of ADHD symptoms, ADHD symptom measurement method, and race were all found to contribute significantly to heterogeneity in effect sizes. Notably, several early life risk factors previously found to be associated with both ADHD and birth weight, gestational age and prenatal smoking exposure, were not found to contribute to heterogeneity in effect sizes. The findings of the current analyses align with the growing recognition that early life adversity contributes to neurodevelopmental difficulties, and the findings highlight the importance of a better understanding of the mechanisms underlying the association between early life risk factors and adverse neurodevelopmental sequela, such as that observed in ADHD.

Development of growth equations from longitudinal studies of body weight and height in the full term and preterm neonate: From birth to four years postnatal age

Physiologically based pharmacokinetic (PBPK) models are developed from compound-independent information to describe important anatomical and physiological characteristics of an individual or population of interest. Modeling pediatric populations is challenging because of the rapid changes that occur during growth, particularly in the first few weeks and months after birth. Neonates who are born premature pose several unique challenges in PBPK model development. To provide appropriate descriptions for body weight (BW) and height (Ht) for age and appropriate incremental gains in PBPK models of the developing preterm and full term neonate, anthropometric measurements collected longitudinally from 1,063 preterm and 158 full term neonates were combined with 2,872 cross-sectional measurements obtained from the NHANES 2007-2010 survey. Age-specific polynomial growth equations for BW and Ht were created for male and female neonates with corresponding gestational birth ages of 25, 28, 31, 34, and 40 weeks. Model-predicted weights at birth were within 20% of published fetal/neonatal reference standards. In comparison to full term neonates, postnatal gains in BW and Ht were slower in preterm subgroups, particularly in those born at earlier gestational ages. Catch up growth for BW in neonates born at 25, 28, 31, and 34 weeks gestational age was complete by 13, 8, 6, and 2 months of life (males) and by 10, 6, 5, and 2 months of life (females), respectively. The polynomial growth equations reported in this paper represent extrauterine growth in full term and preterm neonates and differ from the intrauterine growth standards that were developed for the healthy unborn fetus.

Prematurity and perinatal adversity effects hypothalamic-pituitary-adrenal axis reactivity to social evaluative threat in adulthood

This study examined the long-term effects of prematurity and perinatal adversity on individual differences in stress-related reactivity and regulation of the HPA axis. A prospective sample of 155 infants born preterm and healthy (n = 20), medical illness (n = 48), neurological illness (n = 26), and small for gestational age (n = 24) and full-term (n = 37) were recruited between 1985 and 1989. At age 23 years, multiple saliva samples were collected before and after participation in the Trier Social Stress Test and later assayed for cortisol. Results reveal that at age 23 years, infants born premature with neurological complications showed higher cortisol reactivity to social evaluative threat compared to either their full-term, small for gestation age, medically ill, or healthy preterm peers. Findings are discussed in terms of implications for contemporary theories that propose effects of early adversity on biological sensitivities and susceptibilities, which translate experience into developmental outcomes related to poor health and risk for disease.

Examining solutions to missing data in longitudinal nursing research

PURPOSE

Longitudinal studies are highly valuable in pediatrics because they provide useful data about developmental patterns of child health and behavior over time. When data are missing, the value of the research is impacted. The study's purpose was to (1) introduce a three-step approach to assess and address missing data and (2) illustrate this approach using categorical and continuous-level variables from a longitudinal study of premature infants.

METHODS

A three-step approach with simulations was followed to assess the amount and pattern of missing data and to determine the most appropriate imputation method for the missing data. Patterns of missingness were Missing Completely at Random, Missing at Random, and Not Missing at Random. Missing continuous-level data were imputed using mean replacement, stochastic regression, multiple imputation, and fully conditional specification (FCS). Missing categorical-level data were imputed using last value carried forward, hot-decking, stochastic regression, and FCS. Simulations were used to evaluate these imputation methods under different patterns of missingness at different levels of missing data.

RESULTS

The rate of missingness was 16-23% for continuous variables and 1-28% for categorical variables. FCS imputation provided the least difference in mean and standard deviation estimates for continuous measures. FCS imputation was acceptable for categorical measures. Results obtained through simulation reinforced and confirmed these findings.

PRACTICE IMPLICATIONS

Significant investments are made in the collection of longitudinal data. The prudent handling of missing data can protect these investments and potentially improve the scientific information contained in pediatric longitudinal studies.

UNPACKING THE BURDEN OF CARE FOR INFANTS IN THE NICU

Infants who begin early life in the medicalized environment of the neonatal intensive care unit (NICU) experience disruption to numerous fundamental expectancies. In the NICU, infants are exposed to chronic, extreme stressors that include painful medical procedures and parental separation. Due to their preverbal stage of development, infants are unable to fully express these experiences, and linking these experiences to long-term outcomes has been difficult. This clinical article proposes the terminology Infant Medical Trauma in the NICU (IMTN) to describe the infant experience. Following a discussion of the NICU as an adverse childhood event, the article has three sections: (a) the unique and critical factors that define the newborn period, (b) a review of the IMTN conceptual model, and (c) recommendations for supportive neuroprotective strategies to moderate the intensity of adverse NICU infant experiences.

Social Emotional Factors Increase Risk of Postpartum Depression in Mothers of Preterm Infants

OBJECTIVE

To examine the association of maternal mental health, perceptions of readiness at neonatal intensive care unit (NICU) discharge, and social risk factors with depressive symptoms 1 month postdischarge in mothers of early (<32 weeks), moderate (32-33 weeks), and late (34-36 weeks) preterm infants. A secondary objective was to compare depressive symptoms among mothers in all preterm groups.

STUDY DESIGN

Mothers (n = 734) of preterm infants cared for >5 days in the NICU and participating in a Transition Home Program completed the Fragile Infant Parent Readiness Evaluation prior to discharge for perceptions of NICU staff support, infant well-being, maternal well-being (emotional readiness/competency), and maternal comfort (worry about infant). Mental health history and social risk factors were obtained. At 1 month postdischarge the Edinburgh Postnatal Depression Scale was administered. Group comparisons and logistic regression analyses were run to predict possible depression (Edinburgh Postnatal Depression Scale  ≥10).

RESULTS

Mothers of early, moderate, and late preterm infants reported similar rates of possible depression (20%, 22%, and 18%, respectively) 1 month after NICU discharge. History of mental health disorder, decreased perception of maternal well-being, decreased maternal comfort regarding infant, and decreased perception of family cohesion were associated with possible depression at 1 month postdischarge.

CONCLUSIONS

Mothers with a previous mental health disorder and experiencing negative perceptions of self and infant at NICU discharge were at increased risk for depressive symptomatology 1 month postdischarge regardless of infant gestational age. Comprehensive mental health assessment prior to discharge is essential to identify women at risk and provide appropriate referral.

Infant Medical Trauma in the Neonatal Intensive Care Unit (IMTN): A Proposed Concept for Science and Practice

BACKGROUND

Trauma is an innately subjective experience ensuing from a deeply distressing event. Research has demonstrated that while the environment of the neonatal intensive care unit (NICU) is capable of providing extraordinary lifesaving measures following birth, the experience may be disruptive to several key aspects of early development, placing infants at risk for adverse behavioral, cognitive, and emotional outcomes.

PURPOSE

This article provides rationale for the concept of Infant Medical Trauma in the NICU (IMTN) as a means of describing this unique stress experience. A triad of cumulative early life NICU experiences (stress, parental separation, and pain) is proposed to influence an infant's swinging neurodevelopmental pendulum amid the potential outcomes of risk and resilience.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Creating language that describes the infant experience brings meaning and calls caregivers and parents to action to consider strategies that may improve long-term health. Actively seeking opportunities to decrease the allostatic load of at-risk infants may support an infant's pendulum to swing toward a path of resilience, thereby moderating his or her early life adverse experience.

A Framework of Complex Adaptive Systems: Parents As Partners in the Neonatal Intensive Care Unit

Advances in neonatal care are allowing for increased infant survival; however, neurodevelopmental complications continue. Using a complex adaptive system framework, a broad analysis of the network of agents most influential to vulnerable infants in the neonatal intensive care unit (NICU) is presented: parent, nurse, and organization. By exploring these interconnected relationships and the emergent behaviors, a model of care that increases parental caregiving in the NICU is proposed. Supportive parent caregiving early in an infant's NICU stay has the potential for more sensitive caregiving and enhanced opportunities for attachment, perhaps positively impacting neurodevelopment.

Exposure to Early Life Pain: Long Term Consequences and Contributing Mechanisms

From an evolutionary perspective, adaptations of an organism to its early environment are essential for survival. The occurrence of early life perturbation, coincident with increased developmental plasticity, provides a unique opportunity for such adaptations to become programmed and persist throughout life. However, adaptations that are beneficial to maintaining homeostasis in one's early environment may result in extreme response strategies that confer vulnerability or dysfunction later in life. This review summarizes recent findings in human and animal studies demonstrating that early life pain results in a hypo-/hyper-sensitive phenotype in response to acute and persistent pain and stress later in life. Changes in cognition and immune function in response to early life pain have also been observed. Recent data on the neural mechanisms underlying these long-term changes are discussed, as well as potential strategies to minimize the impact of early life pain.

Integrative Review of Genetic Factors Influencing Neurodevelopmental Outcomes in Preterm Infants

Preterm infants are at elevated risk for a host of neurodevelopmental problems, including disorders that appear later in life. Gene-environment interactions and prematurity may combine to increase the risk for poor neurodevelopmental outcomes. Increasing evidence supports a genetic link to risk for atypical development; however, no genomic risk profiles are currently used for infants without apparent genetic disorders. The purpose of this review was to synthesize recent evidence of genetic associations with atypical neurodevelopmental outcomes that may affect preterm infants who do not have a rare genetic disease. Electronic and hand-search strategies were used to find relevant articles that were English-language, peer-reviewed primary research or meta-analysis reports published between July 2009 and July 2014, involving human participants. Articles included in the analysis (N = 29) used a wide range of study designs and methodologies, complicating the analysis. An integrative-review design was used to synthesize the data. Numerous genes (n = 43) and additional large deletion copy number variants were associated with neurodevelopmental outcomes, including cognition, attention, perception, psychiatric disease, autism spectrum disorder, cerebral palsy, infant behavior, and alterations in brain architecture. The creation of genetic risk profiles for complex disorders of neurodevelopment is presently hindered by inconsistent genetic-association evidence, methodological considerations, reporting problems, and lack of replication. However, several avenues of investigation offer promise, including large (>100 kb) copy number variants and the candidate genes MET, NRG3, and SLC6A4, each of which were reported to have associations with neurodevelopmental outcomes in multiple, high-quality studies.

The long-term impact of early life pain on adult responses to anxiety and stress: Historical perspectives and empirical evidence

Approximately 1 in 6 infants are born prematurely each year. Typically, these infants spend 25 days in the Neonatal Intensive Care Unit (NICU) where they experience 10-18 painful and inflammatory procedures each day. Remarkably, pre-emptive analgesics and/or anesthesia are administered less than 25% of the time. Unalleviated pain during the perinatal period is associated with permanent decreases in pain sensitivity, blunted cortisol responses and high rates of neuropsychiatric disorders. To date, the mechanism(s) by which these long-term changes in stress and pain behavior occur, and whether such alterations can be prevented by appropriate analgesia at the time of insult, remains unclear. Work in our lab using a rodent model of early life pain suggests that inflammatory pain experienced on the day of birth blunts adult responses to stress- and pain-provoking stimuli, and dysregulates the hypothalamic pituitary adrenal (HPA) axis in part through a permanent upregulation in central endogenous opioid tone. This review focuses on the long-term impact of neonatal inflammatory pain on adult anxiety- and stress-related responses, and underlying neuroanatomical changes in the context of endogenous pain control and the HPA axis. These two systems are in a state of exaggerated developmental plasticity early in postnatal life, and work in concert to respond to noxious or aversive stimuli. We present empirical evidence from animal and clinical studies, and discuss historical perspectives underlying the lack of analgesia/anesthetic use for early life pain in the modern NICU.

Ritual circumcision and risk of autism spectrum disorder in 0- to 9-year-old boys: national cohort study in Denmark

OBJECTIVE

Based on converging observations in animal, clinical and ecological studies, we hypothesised a possible impact of ritual circumcision on the subsequent risk of autism spectrum disorder (ASD) in young boys.

DESIGN

National, register-based cohort study.

SETTING

Denmark.

PARTICIPANTS

A total of 342,877 boys born between 1994 and 2003 and followed in the age span 0-9 years between 1994 and 2013.

MAIN OUTCOME MEASURES

Information about cohort members' ritual circumcisions, confounders and ASD outcomes, as well as two supplementary outcomes, hyperkinetic disorder and asthma, was obtained from national registers. Hazard ratios (HRs) with 95% confidence intervals (CIs) associated with foreskin status were obtained using Cox proportional hazards regression analyses.

RESULTS

With a total of 4986 ASD cases, our study showed that regardless of cultural background circumcised boys were more likely than intact boys to develop ASD before age 10 years (HR = 1.46; 95% CI: 1.11-1.93). Risk was particularly high for infantile autism before age five years (HR = 2.06; 95% CI: 1.36-3.13). Circumcised boys in non-Muslim families were also more likely to develop hyperkinetic disorder (HR = 1.81; 95% CI: 1.11-2.96). Associations with asthma were consistently inconspicuous (HR = 0.96; 95% CI: 0.84-1.10).

CONCLUSIONS

We confirmed our hypothesis that boys who undergo ritual circumcision may run a greater risk of developing ASD. This finding, and the unexpected observation of an increased risk of hyperactivity disorder among circumcised boys in non-Muslim families, need attention, particularly because data limitations most likely rendered our HR estimates conservative. Considering the widespread practice of non-therapeutic circumcision in infancy and childhood around the world, confirmatory studies should be given priority.

The impact of preterm birth on participation in childhood occupation

Outcome studies of premature babies have focused their assessments predominately on neurodevelopmental impairments without relating these deficits to the impact they have on a child's everyday life. This study aims to determine whether very 'preterm birth alone' impacts on a child's ability to participate in and carry out childhood activities. Forty-four former premature infants between 6 months and 5 years 6 months, born in Galway University Hospital, Ireland, without physical or intellectual disability, were compared with 51 age-matched term-born infants. Study infants had an average gestation of 29 weeks and birth weight of 1,145 g. Functional skills were assessed using the Adaptive Behavior Assessment Scale-II and the Assessment of Preschool Children's Participation. Premature infants had significantly lower mean scores in overall adaptive behaviour compared to term infants, regardless of whether chronological (difference = 13.6, 95% (CI) = [8.2, 19.1]) or corrected (difference = 6.6, 95% CI = [1.4, 11.8]) age was used. Premature infants had lower mean scores in conceptual, social and practical skills, but no difference was found between the groups in intensity or diversity of participation.

CONCLUSION

Premature infants had significantly lower scores in adaptive behaviour than term infants. This measurable effect of preterm birth on 'childhood occupations' merits further investigation.

Neuroimmune mechanisms of stress: sex differences, developmental plasticity, and implications for pharmacotherapy of stress-related disease

The last decade has witnessed profound growth in studies examining the role of fundamental neuroimmune processes as key mechanisms that might form a natural bridge between normal physiology and pathological outcomes. Rooted in core concepts from psychoneuroimmunology, this review utilizes a succinct, exemplar-driven approach of several model systems that contribute significantly to our knowledge of the mechanisms by which neuroimmune processes interact with stress physiology. Specifically, we review recent evidence showing that (i) stress challenges produce time-dependent and stressor-specific patterns of cytokine/chemokine expression in the CNS; (ii) inflammation-related genes exhibit unique expression profiles in males and females depending upon individual, cooperative or antagonistic interactions between steroid hormone receptors (estrogen and glucocorticoid receptors); (iii) adverse social experiences incurred through repeated social defeat engage a dynamic process of immune cell migration from the bone marrow to brain and prime neuroimmune function and (iv) early developmental exposure to an inflammatory stimulus (carageenin injection into the hindpaw) has a lasting influence on stress reactivity across the lifespan. As such, the present review provides a theoretical framework for understanding the role that neuroimmune mechanisms might play in stress plasticity and pathological outcomes, while at the same time pointing toward features of the individual (sex, developmental experience, stress history) that might ultimately be used for the development of personalized strategies for therapeutic intervention in stress-related pathologies.

Perinatal complications and aging indicators by midlife

BACKGROUND

Perinatal complications predict increased risk for morbidity and early mortality. Evidence of perinatal programming of adult mortality raises the question of what mechanisms embed this long-term effect. We tested a hypothesis related to the theory of developmental origins of health and disease: that perinatal complications assessed at birth predict indicators of accelerated aging by midlife.

METHODS

Perinatal complications, including both maternal and neonatal complications, were assessed in the Dunedin Multidisciplinary Health and Development Study cohort (N = 1037), a 38-year, prospective longitudinal study of a representative birth cohort. Two aging indicators were assessed at age 38 years, objectively by leukocyte telomere length (TL) and subjectively by perceived facial age.

RESULTS

Perinatal complications predicted both leukocyte TL (β = -0.101; 95% confidence interval, -0.169 to -0.033; P = .004) and perceived age (β = 0.097; 95% confidence interval, 0.029 to 0.165; P = .005) by midlife. We repeated analyses with controls for measures of family history and social risk that could predispose to perinatal complications and accelerated aging, and for measures of poor health taken in between birth and the age-38 follow-up. These covariates attenuated, but did not fully explain the associations observed between perinatal complications and aging indicators.

CONCLUSIONS

Our findings provide support for early-life developmental programming by linking newborns' perinatal complications to accelerated aging at midlife. We observed indications of accelerated aging "inside," as measured by leukocyte TL, an indicator of cellular aging, and "outside," as measured by perceived age, an indicator of declining tissue integrity. A better understanding of mechanisms underlying perinatal programming of adult aging is needed.

Long-term dysregulation of brain corticotrophin and glucocorticoid receptors and stress reactivity by single early-life pain experience in male and female rats

Inflammatory pain experienced on the day of birth (postnatal day 0: PD0) significantly dampens behavioral responses to stress- and anxiety-provoking stimuli in adult rats. However, to date, the mechanisms by which early life pain permanently alters adult stress responses remain unknown. The present studies examined the impact of inflammatory pain, experienced on the day of birth, on adult expression of receptors or proteins implicated in the activation and termination of the stress response, including corticotrophin releasing factor receptors (CRFR1 and CRFR2) and glucocorticoid receptor (GR). Using competitive receptor autoradiography, we show that Sprague Dawley male and female rat pups administered 1% carrageenan into the intraplantar surface of the hindpaw on the day of birth have significantly decreased CRFR1 binding in the basolateral amygdala and midbrain periaqueductal gray in adulthood. In contrast, CRFR2 binding, which is associated with stress termination, was significantly increased in the lateral septum and cortical amygdala. GR expression, measured with in situ hybridization and immunohistochemistry, was significantly increased in the paraventricular nucleus of the hypothalamus and significantly decreased in the hippocampus of neonatally injured adults. In parallel, acute stress-induced corticosterone release was significantly attenuated and returned to baseline more rapidly in adults injured on PD0 in comparison to controls. Collectively, these data show that early life pain alters neural circuits that regulate responses to and neuroendocrine recovery from stress, and suggest that pain experienced by infants in the Neonatal Intensive Care Unit may permanently alter future responses to anxiety- and stress-provoking stimuli.

Structural and functional brain correlates of behavioral outcomes during adolescence

Several studies have described an association between very preterm birth and behavioral and psychiatric outcomes in childhood and adolescence. The exact mechanisms underlying this association are unknown, but impaired neurodevelopment has been proposed as a possible etiological factor. Existing research suggests a selective vulnerability of brain regions associated with a variety of behavioral and psychiatric outcomes following very preterm birth. This article reviews studies that have directly explored the structural and functional brain correlates of behavioral outcomes in ex-preterm individuals, with an emphasis on attentional problems, overall mental health functioning including internalizing and externalizing scores, and psychosocial adjustment. The focus here is on neuroimaging research conducted during adolescence, a period of life associated with the emergence and early expression of several psychiatric disorders. The neurodevelopmental hypothesis is used as a theoretical framework, according to which early brain lesions interact with the developing brain to increase later vulnerability to psychopathology.

17-year outcome of preterm infants with diverse neonatal morbidities: part 2, impact on activities and participation

PURPOSE

To examine functioning and participation in a diverse U.S. sample of 180 infants at age 17 years.

DESIGN AND METHODS

The World Health Organization International Classification of Functioning, Disability and Health model framed functioning and participation domains and contextual factors. Assessment included cognition, executive functioning, academic achievement, personal functioning, community participation, and social involvement.

RESULTS

Socioeconomic status, not prematurity, impacted cognitive and academic outcomes. Across neonatal morbidities, male gender and social disadvantage are key determinants of cognitive, academic, and social functioning.

PRACTICE IMPLICATIONS

Interventions addressing academic and social-behavioral competencies in early school years may potentially optimize long-term preterm outcomes.