Sleep and prematurity: sleep outcomes in preterm children and influencing factors

Impact of daily music on comfort scores in preterm infants: a randomized controlled trial

BACKGROUND

Premature birth heightens neurodevelopmental risks, theorized to partly stem from altered sensory inputs and disrupted sleep patterns. Modifying the acoustic milieu through music intervention (MI) offers promise to improve neonatal comfort, reduce sleep disturbances, and stabilize physiological parameters. This study explores the impact of non-pharmacological MI on these health indicators within the Neonatal Intensive Care Unit (NICU).

METHODS

A single-blinded RCT was conducted. Premature infants (34 > GA > 29 wks) were randomly assigned to either receive 8 min of daily MI or placebo for up to 15 days. Validated behavioral comfort scores were visually obtained by a blinded observer before and after intervention. Additionally, physiological signs (HR, RR, SatO2) were recorded. Differences between the groups were analyzed using χ² tests and t-tests.

RESULTS

In total 56 preterm infants were included. After intervention, comfort levels increased significantly in the MI compared to placebo group (p = 0.000). Neonates receiving MI transitioned from wakefulness to a state of sleep significantly more compared to placebo (p = 0.002). Physiological parameters remained stable.

CONCLUSIONS

This study adds to existing literature demonstrating that a music intervention in a NICU setting can enhance comfort and sleep of premature infants without adversely affecting physiological parameters.

IMPACT

The study demonstrates that music interventions (MI) in a Neonatal Intensive Care Unit (NICU) setting can significantly increase comfort levels and positively impact the sleep of premature infants without negatively impacting their physiological parameters. This research increases evidence for non-pharmacological interventions, specifically music, as beneficial for the well-being of premature infants in NICU settings. It replicates and expands upon previous methodological designs, providing more robust evidence of MI's positive effects on this vulnerable population. The positive outcomes of music intervention could influence hospital policies by integrating non-pharmacological practices into standard neonatal care protocols to enhance developmental support for premature infants.

Associations of Infant Sleep Characteristics with Childhood Cognitive Outcomes

OBJECTIVE

The objective of this study was to quantify associations of infant 24-hour sleep duration and nighttime sleep consolidation with later child cognition.

METHODS

This study included children from Project Viva, a prospective cohort in Massachusetts with (1) sleep measures in infancy (median age 6.4 months) and (2) child cognition in early childhood (median age 3.2 years) or mid-childhood (median age 7.7 years). Main exposures were parental reports of infant 24-hour sleep duration and nighttime sleep consolidation (% of total daily sleep occurring at nighttime). Cognitive outcomes were (1) early childhood vocabulary and visual-motor abilities and (2) mid-childhood verbal and nonverbal intelligence quotient (IQ), memory, and visual-motor abilities. We examined associations of infant sleep with childhood cognition using linear regression models adjusted for child sex, age, and race or ethnicity; maternal age, education, and parity; and household income.

RESULTS

Early and mid-childhood analyses included 1102 and 969 children, respectively. Most mothers reported infant race or ethnicity as White (69%) and were college graduates (71%). The mean infant 24-hour sleep duration was 12.2 ± 2.0 hours, and the mean nighttime sleep consolidation was 76.8% ± 8.8%. Infant 24-hour sleep duration was not associated with any early or mid-childhood outcomes. Higher infant nighttime sleep consolidation was associated with higher mid-childhood verbal intelligence (β: 0.12 points per % nighttime sleep; 95% CI, 0.01-0.22), but not with any early childhood cognitive measures.

CONCLUSION

In this cohort, higher infant nighttime sleep consolidation was associated with higher verbal IQ in mid-childhood. Future studies should investigate causal relationships of infant sleep consolidation with child cognition among diverse populations.

Sleep as a driver of pre- and postnatal brain development

In 1966, Howard Roffwarg proposed the ontogenic sleep hypothesis, relating neural plasticity and development to rapid eye movement (REM) sleep, a hypothesis that current fetal and neonatal sleep research is still exploring. Recently, technological advances have enabled researchers to automatically quantify neonatal sleep architecture, which has caused a resurgence of research in this field as attempts are made to further elucidate the important role of sleep in pre- and postnatal brain development. This article will review our current understanding of the role of sleep as a driver of brain development and identify possible areas for future research. IMPACT: The evidence to date suggests that Roffwarg's ontogenesis hypothesis of sleep and brain development is correct. A better understanding of the relationship between sleep and the development of functional connectivity is needed. Reliable, non-invasive tools to assess sleep in the NICU and at home need to be tested in a real-world environment and the best way to promote healthy sleep needs to be understood before clinical trials promoting and optimizing sleep quality in neonates could be undertaken.

Combining developmental and sleep health measures for autism spectrum disorder screening: an ECHO study

BACKGROUND

Sleep problems are reported for up to 80% of autistic individuals. We examined whether parsimonious sets of items derived from the Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) and the Brief Infant Sleep Questionnaire (BISQ) are superior to the standard M-CHAT-R in predicting subsequent autism spectrum disorder (ASD) diagnoses.

METHODS

Participants from 11 Environmental influences on Child Health Outcomes (ECHO) cohorts were included. We performed logistic LASSO regression models with 10-fold cross-validation to identify whether a combination of items derived from the M-CHAT-R and BISQ are superior to the standard M-CHAT-R in predicting ASD diagnoses.

RESULTS

The final sample comprised 1552 children. The standard M-CHAT-R had a sensitivity of 44% (95% CI: 34, 55), specificity of 92% (95% CI: 91, 94), and AUROC of 0.726 (95% CI: 0.663, 0.790). A higher proportion of children with ASD had difficulty falling asleep or resisted bedtime during infancy/toddlerhood. However, LASSO models revealed parental reports of sleep problems did not improve the accuracy of the M-CHAT-R in predicting ASD diagnosis.

CONCLUSION

While children with ASD had higher rates of sleep problems during infancy/toddlerhood, there was no improvement in ASD developmental screening through the incorporation of parent-report sleep metrics.

IMPACT

Parental-reported sleep problems are common in autism spectrum disorder (ASD). We investigated whether the inclusion of parental-reports of infant/toddler sleep patterns enhanced the effectiveness of developmental screening for autism. We reported higher rates of difficulty falling asleep and resisting bedtime during infancy and toddlerhood among children later diagnosed with ASD; however, we did not find an improvement in ASD developmental screening through the incorporation of parent-report sleep metrics. In our sample, the standard M-CHAT-R had a sensitivity of 39% among children of mothers with government insurance compared with a sensitivity of 53% among children of mothers with employer-based insurance.

Polysomnographically Defined Restless Sleep Disorder and Periodic Limb Movements during Sleep in Children Born Prematurely

INTRODUCTION

Children born prematurely (<37 weeks' gestation) are at increased risk of perinatal complications, comorbidities, and iron deficiency. Iron deficiency is associated with restless legs syndrome and periodic limb movement disorder. In this study, we assessed the prevalence of restless sleep disorder (RSD) and elevated periodic limb movements during sleep (PLMS) in children born prematurely who underwent polysomnography.

METHODS

A retrospective chart review of sleep studies was conducted in children aged 1-18 years (median age 4 years) with a history of premature birth. Children with genetic syndrome, airway surgery, or tracheostomy were excluded. Three groups were compared: children with PLMS index >5, children with RSD, and children with neither elevated PLMS index nor RSD.

RESULTS

During the study, 2577 sleep studies were reviewed. Ninety-two studies fit our criteria and were included in the analysis. The median age at birth was 31 weeks, and the interquartile range (IQR) was 27-34 weeks. A total of 32 (34.8%) children were referred for restless sleep and 55 (59.8%) for snoring. After polysomnography, 18% were found to have a PLMS index >5/h, and 14% fit the criteria for restless sleep disorder (RSD). There were no statistically significant differences in PSG parameters among the children with RSD, PLMS, and the remaining group, except for lower obstructive apnea/hypopnea index (Kruskal-Wallis ANOVA 8.621, p = 0.0135) in the RSD group (median 0.7, IQR 0.3-0.9) than in the PLMS (median 1.7, IQR 0.7-3.5) or the non-RSD/non-PLMS (median 2.0, IQR 0.8-4.5) groups.

CONCLUSIONS

There was an elevated frequency of RSD and elevated PLMS in our cohort of children born prematurely. Children born prematurely are at higher risk of iron deficiency which can be a contributor factor to sleep -related movement disorders. These results add new knowledge regarding the prevalence of RSD and PLMS in these children.

Effects of caffeine therapy for apnea of prematurity on sleep and neurodevelopment of preterm infants at 6 months of corrected age

STUDY OBJECTIVES

To determine the differences in sleep patterns between preterm infants who received caffeine and those who did not and to evaluate the effects of caffeine therapy on early neurodevelopment. Secondarily, actigraphy and polysomnography were compared to evaluate the sleep of preterm infants.

METHODS

Twenty-eight preterm infants ages 28-34 weeks admitted to a single-center Level III neonatal intensive care unit between May 2020 and May 2021 were included. Sleep was assessed by actigraphy for 72 hours with Respironics Mini-Mitter® Actiwatch-2 and Brief Infant Sleep Questionnaire at 6 months corrected age. On the first day of actigraphy, infants underwent polysomnography between 10:00 am and 3:00 pm. Neurodevelopment was evaluated by the Bayley Scales of Infant and Toddler Development-III, the Ages & Stages Questionnaire, and the Hammersmith Infant Neurological Examination.

RESULTS

There were no significant differences in sleep parameters measured by actigraphy, the Brief Infant Sleep Questionnaire, and polysomnography between infants in the caffeine group (n = 12) and no-caffeine group (n = 16). Sensitivity (91.07%) and agreement rate (77.21%) for the actigraphy against polysomnography were highest at the automatic threshold. No significant differences were observed in the neurodevelopment of infants in the caffeine group compared to the no-caffeine group.

CONCLUSIONS

Sleep parameters and neurodevelopmental outcomes were not different in infants at 6 months of corrected age with regard to caffeine therapy. Actigraphy at the automatic threshold can be used in infants for sleep pattern assessment.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Influence of Caffeine Therapy in Preterm Infants; URL: https://www.clinicaltrials.gov/ct2/show/NCT04376749; Identifier: NCT04376749.

CITATION

Atalah YEY, Barış HE, Akdere SK, et al. Effects of caffeine therapy for apnea of prematurity on sleep and neurodevelopment of preterm infants at 6 months of corrected age. J Clin Sleep Med. 2023;19(12):2075-2085.

Multisensory stimulation bundles on sleep and neurobehavioral development in the first year after birth in very preterm infants: a randomized crossover controlled study protocol

BACKGROUND

Disrupted sleep is believed to contribute to short- and long-term neurodevelopmental problems in very preterm infants (VPIs). This study presents a protocol for an evaluator-blinded, randomized crossover trial. It aims to assess the sleep efficiency of hospitalized VPIs by providing multisensory stimulation bundles. Furthermore, it aims to observe the intervention impacts on sleep during hospitalization of the VPIs and their sleep and neurodevelopmental outcomes during the first year of post-discharge follow-up.

METHODS

The study will be conducted in the neonatology department of a tertiary pediatric teaching hospital. All the eligible VPIs will undergo two types of care in random order: "standard care" (2 weeks) and "standard care plus multisensory stimulation bundles," each lasting 2 weeks. A generated list of random numbers will be used for case sequence allocation. Sleep outcomes will be evaluated using the Actiwatch-2 Actigraph. Moreover, the amplitude-integrated electroencephalography and the Griffiths Mental Development Scales will be used to measure the neurodevelopmental outcomes during hospitalization and in the first year of follow-up of the VPIs.

DISCUSSION

The intervention protocol of this study differs from that of other traditional interventions by producing precise and consistent supportive stimulations, similar to maternal tactile, auditory, posture, and visual effects for hospitalized VPIs. This protocol could be an effective measure to facilitate sleep and early neurodevelopment of VPIs. The expected outcomes will help confirm the implementation and generalization of the multisensory stimulation bundles' care protocol in neonatology departments. We expect that the study will positively impact hospitalized VPIs, especially in their sleep and early neurodevelopmental outcomes. It will also provide a new perspective regarding parent and infant interaction strategies, particularly for newborn intensive care units that limit visits because of the global spread of COVID-19.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR 2200059099. Registered on 25 April 2022, https://www.chictr.org.cn/showproj.html?proj=166980 ; the Hospital Research Ethics Committee (approval number: SCMCIRB-K2021086-1, Version 01), approved on 21 January 2022.

Sleep disturbances are associated with feeding practices and age in preterm infants

BACKGROUND

Preterm infants are under risk of several shortcomings including sleep disturbances (SD). This cross-sectional study evaluated factors associated with SD in preterm and low birth weight infants in a reference center for preterm children at a University Hospital, southeastern Brazil.

METHODS

A hundred-four dyads of mothers-infants 0-3 years participated. Mothers answered an online questionnaire (Google Forms®) evaluating childbirth characteristics, gestational age, breastfeeding, bottle feeding, non-nutritive sucking habits and sociodemographic information. The Brazilian version of the Brief Infant Sleep Questionnaire (BISQ) evaluated SD. Bivariate and Logistic Regression analyses were performed (p < 0.05).

RESULTS

SD was present in 45.2% of the sample. Multivariate Logistic Regression Model showed that infants breastfed ≥3 times at night had 5.006 more chances to have SD (CI 95% = 1.229-20.400) compared to those who did not breastfeed at night. Infants who were bottle-fed 3 ≥ times at night had 6.952 more chances to have SD (CI = 95% = 1.364-35.427) compared to those who were bottle fed less frequently. The chance of SD decreased 6.6% (CI 95% = 0.889-0.982) for each increase of a month in infant's age, and infants from families with higher income had 3.535 more chances to have SD (CI 95% = 1.006-12.416).

CONCLUSION

The younger the child, a higher frequency of night feeding and belonging to higher income families were associated with SD. Recognizing the associated factors with SD in newborns and infants can aid families to better deal with this issue, promote better sleep quality and individualized counseling.

Small vulnerable newborns-big potential for impact

Despite major achievements in child survival, the burden of neonatal mortality has remained high and even increased in some countries since 1990. Currently, most neonatal deaths are attributable to being born preterm, small for gestational age (SGA), or with low birthweight (LBW). Besides neonatal mortality, these conditions are associated with stillbirth and multiple morbidities, with short-term and long-term adverse consequences for the newborn, their families, and society, resulting in a major loss of human capital. Prevention of preterm birth, SGA, and LBW is thus critical for global child health and broader societal development. Progress has, however, been slow, largely because of the global community's failure to agree on the definition and magnitude of newborn vulnerability and best ways to address it, to frame the problem attractively, and to build a broad coalition of actors and a suitable governance structure to implement a change. We propose a new definition and a conceptual framework, bringing preterm birth, SGA, and LBW together under a broader umbrella term of the small vulnerable newborn (SVN). Adoption of the framework and the unified definition can facilitate improved problem definition and improved programming for SVN prevention. Interventions aiming at SVN prevention would result in a healthier start for live-born infants, while also reducing the number of stillbirths, improving maternal health, and contributing to a positive economic and social development in the society.

Sleep and 24-hour rhythm characteristics in preschool children born very preterm and full term

STUDY OBJECTIVES

Sleep impacts the quality of life and is associated with cardiometabolic and neurocognitive outcomes. Little is known about the sleep of preterm-born children at preschool age. We, therefore, studied sleep and 24-hour rhythms of preschool children born very preterm compared with full-term children.

METHODS

This was a prospective cohort study comparing sleep quality and quantity of children born very preterm (gestational age [GA] < 30 weeks) with full-term children at the (corrected) age of 3 years, using (1) 2 parent-reported questionnaires (Brief Infant Sleep Questionnaire and The Munich Chronotype Questionnaire) and (2) at least 3 days of triaxial wrist actigraphy combined with sleep diary. We performed regression analyses with adjustment for sex (corrected), age, and birth weight standard deviation (SD) score.

RESULTS

Ninety-seven very-preterm-born (median GA 27+5; interquartile range 26 + 3;29 + 0 weeks) and 92 full-term children (GA 39 + 3; 38 + 4;40 + 4 weeks) were included. Sleep problems and other reported sleep parameters were not different between groups. As measured with actigraphy, sleep and 24-hour rhythm were similar between groups, except for very-preterm born children waking up 21 minutes (4;38) minutes later than full-term children (adjusted P = .001).

CONCLUSIONS

Based on parent reports and actigraphy, very-preterm-born children sleep quite similar to full-term controls at the corrected age of 3 years. Reported sleep problems were not different between groups. Actigraphy data suggest that preterm-born children may wake up later than children born full term. Further studies are needed to explore how sleep relates to cardiometabolic and neurodevelopmental outcomes after preterm birth and whether early interventions are useful to optimize 24-hour rhythm and sleep.

CITATION

Bijlsma A, Beunders VAA, Dorrepaal DJ, et al. Sleep and 24-hour rhythm characteristics in preschool children born very preterm and full term. J Clin Sleep Med. 2023;19(4):685-693.

Fetal and infant growth patterns, sleep, and 24-h activity rhythms: a population-based prospective cohort study in school-age children

The study objective was to explore associations of fetal and infant weight patterns and preterm birth with sleep and 24-h activity rhythm parameters at school-age. In our prospective population-based study, 1327 children were followed from birth to age 10-15 years. Fetal weight was estimated using ultrasound in the second and third trimester of pregnancy. Birth weight and gestational age were available from midwife registries. Infant weight was measured at 6, 12 and 24 months. Fetal and infant weight acceleration or deceleration were defined as a change of >0.67 standard deviation between the corresponding age intervals. At school-age, sleep duration, sleep efficiency, wake after sleep onset, social jetlag, inter-daily stability, and intra-daily variability were assessed using tri-axial wrist actigraphy for 9 consecutive nights. We observed that low birth weight (<2500 g) was associated with 0.24 standard deviation (95% confidence interval [CI] 0.04; 0.43) longer sleep duration compared to normal weight. Compared to normal growth, growth deceleration in fetal life and infancy was associated with 0.40 standard deviation (95% CI 0.07; 0.73) longer sleep duration, 0.44 standard deviation (95% CI 0.14; 0.73) higher sleep efficiency, and -0.41 standard deviation (95% CI -0.76; -0.07) shorter wake after sleep onset. A pattern of normal fetal growth followed by infant growth acceleration was associated with -0.40 standard deviation (95% CI -0.61; -0.19) lower inter-daily stability. Preterm birth was not associated with any sleep or 24-h rhythm parameters. Our findings showed that children with fetal and infant growth restriction had longer and more efficient sleep at school-age, which may be indicative of an increased need for sleep for maturational processes and development after a difficult start in life.

Sleep assessment in preterm infants: Use of actigraphy and aEEG

OBJECTIVE

Objective methods to monitor the sleep of preterm infants at the neonatal intensive care unit (NICU) are required to prevent potentially adverse neurodevelopmental outcomes. This study aimed to determine the concordance of actigraphy and amplitude-integrated electroencephalogram (aEEG) against gold standard direct observation (DO) in assessing sleep/wake states of typically developing preterm infants.

METHODS

This prospective observational study was conducted in a single center level III NICU. Sleep variables were measured using Philips Respironics Mini-Mitter® Actiwatch-2 for 24 h and compared with 8-h matched data of aEEG and DO. Sensitivity-specificity analysis, Cohen's kappa, prevalence-adjusted and bias-adjusted kappa (PABAK), and Bland Altman plots were generated.

RESULTS

Seventeen preterm infants were recruited. A total of 11252 epochs were studied. Sensitivity (86.4%), agreement rate (67.9%), and predictive value for wake (47.9%) for the actigraphy were highest at the automatic activity threshold whereas specificity (54.5%) and predictive value for sleep (75.5%) were highest at low threshold. The sensitivity of aEEG was 79.3% and the specificity was 54.3%. At all thresholds, the agreement was largely equivalent with low kappas (0.14-0.17) and PABAK coefficients (0.22-0.35) for actigraphy and DO. Moderate agreement was observed between aEEG and DO according to the PABAK coefficient (0.44). Mean differences in sleep parameters were not different between DO and aEEG as well as DO/aEEG and actigraphy at medium threshold (p > 0.05).

CONCLUSIONS

Actigraphy at medium threshold can be used in depicting sleep in typically developing preterm infants at NICU. aEEG may be an alternative adjunctive method to actigraphy for the evaluation of sleep/wake states in the NICU setting.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04145362.

Precision caffeine therapy for apnea of prematurity and circadian rhythms: New possibilities open up

Caffeine is the globally consumed psychoactive substance and the drug of choice for the treatment of apnea of prematurity (AOP), but its therapeutic effects are highly variable among preterm infants. Many of the molecular underpinnings of the marked individual response have remained elusive yet. Interestingly, the significant association between Clock gene polymorphisms and the response to caffeine therapy offers an opportunity to advance our understanding of potential mechanistic pathways. In this review, we delineate the functions and mechanisms of human circadian rhythms. An up-to-date advance of the formation and ontogeny of human circadian rhythms during the perinatal period are concisely discussed. Specially, we summarize and discuss the characteristics of circadian rhythms in preterm infants. Second, we discuss the role of caffeine consumption on the circadian rhythms in animal models and human, especially in neonates and preterm infants. Finally, we postulate how circadian-based therapeutic initiatives could open new possibilities to promote precision caffeine therapy for the AOP management in preterm infants.

Comparison of the Effect of Nesting and Swaddling on Sleep Duration and Arousal Frequency among Preterm Neonates: A Randomized Clinical Trial

Introduction: Sleep contributes a pivotal part in neurological improvement of new borns. New-borns admitted to neonatal intensive care unit (NICU) perceive many sounds of monitors and this disturb their rest period. To enhance the sleep duration of neonates many non-pharmacological methods are available like placing newborn in a nest made with rolled cotton bed sheet and wrapping the baby with white cotton cloth. In this research effect of these two positions were assessed.

Methods: A randomized clinical trial was carried out on 76 preterm neonates in NICU of a tertiary care center. Neonates were included in the study by random method. Sleep duration and frequency of arousal was assessed through direct observation. Physiological parameters were assessed by using cardiac monitor. The information collected were analyzed using SPSS version 21.

Results: Sleep duration of nesting group showed significantly higher than swaddling group, which mean (SD) was 206.4 (28), 183.1 (34.78) minutes, respectively. Additionally, waking up was observed less frequency in the nesting group.

Conclusion: Nesting enhances the duration of sleep among preterm neonates and hence this can be given priority in NICU.

Prevalence of Sleep Problems and Its Association With Preterm Birth Among Kindergarten Children in a Rural Area of Shanghai, China

INTRODUCTION

Healthy sleep in children is critical for their physical and mental health. Although growing evidence indicates the linkage between preterm birth and neural network that regulates sleep architecture, findings on the association between preterm birth and sleep problems among children are still contradictory. In this study, we aimed to understand the prevalence of sleep problems in children aged 3-6 years and to explore the association between sleep problems and preterm birth among children in Shanghai, China.

METHODS

We selected 8,586 kindergarten children aged 3-6 years and their mothers in a rural area of Shanghai. Data were collected by questionnaire interview among mothers with informed consent that was signed ahead. Six types of sleep problems (i.e., insufficient sleep, sleepwalk, nightmare, snore, grind teeth, and cry in sleep) were selected in this study. SAS 9.4 was used for data analysis, and p < 0.05 was considered statistically significant.

RESULTS

In this study, the prevalence of preterm birth was 9.88% (848/8,586), with a higher prevalence in boys (10.62%) than girls (9.01%). The prevalence of sleep problems was 89.81% among kindergarten children, with 62.50% for snore, 50.35% for grind teeth, 49.20% for cry in sleep, 41.18% for nightmare, 11.67% for insufficient sleep, and 4.44% for sleepwalk. The age of children, family income, and mother's education were associated with the prevalence of sleep problems in children. Logistic regression indicated that sleep problems in preterm children were comparable with the full-term children [odds ratio = 1.13, 95% confidence interval (0.89-1.45)].

CONCLUSION

Sleep problems were prevalent among children aged 3-6 years in the rural area of Shanghai, and preterm birth was not associated with sleep problems in kindergarten children. We recommend that parents should create limit setting in the home, cultivate similar child-rearing attitudes and beliefs among family members, and encourage children to go to bed earlier.

Heart rate variability in neonatal seizures: Investigation and implications for management

Many factors acting during the neonatal period can affect neurological development of the infant. Neonatal seizures (NS) that frequently occur in the immature brain may influence autonomic maturation and lead to detectable cardiovascular signs. These autonomic manifestations can also have significant diagnostic and prognostic value. The analysis of Heart Rate Variability (HRV) represents the most used and feasible method to evaluate cardiac autonomic regulation. This narrative review summarizes studies investigating HRV dynamics in newborns with seizures, with the aim of highlighting the potential utility of HRV measures for seizure detection and management. While HRV analysis in critically ill newborns is influenced by many potential confounders, we suggest that it can enhance the ability to better diagnose seizures in the clinical setting. We present potential applications of the analysis of HRV, which could have a useful future role, beyond the research setting.

A Review on the Vagus Nerve and Autonomic Nervous System During Fetal Development: Searching for Critical Windows

The autonomic nervous system (ANS) is one of the main biological systems that regulates the body's physiology. Autonomic nervous system regulatory capacity begins before birth as the sympathetic and parasympathetic activity contributes significantly to the fetus' development. In particular, several studies have shown how vagus nerve is involved in many vital processes during fetal, perinatal, and postnatal life: from the regulation of inflammation through the anti-inflammatory cholinergic pathway, which may affect the functioning of each organ, to the production of hormones involved in bioenergetic metabolism. In addition, the vagus nerve has been recognized as the primary afferent pathway capable of transmitting information to the brain from every organ of the body. Therefore, this hypothesis paper aims to review the development of ANS during fetal and perinatal life, focusing particularly on the vagus nerve, to identify possible "critical windows" that could impact its maturation. These "critical windows" could help clinicians know when to monitor fetuses to effectively assess the developmental status of both ANS and specifically the vagus nerve. In addition, this paper will focus on which factors-i.e., fetal characteristics and behaviors, maternal lifestyle and pathologies, placental health and dysfunction, labor, incubator conditions, and drug exposure-may have an impact on the development of the vagus during the above-mentioned "critical window" and how. This analysis could help clinicians and stakeholders define precise guidelines for improving the management of fetuses and newborns, particularly to reduce the potential adverse environmental impacts on ANS development that may lead to persistent long-term consequences. Since the development of ANS and the vagus influence have been shown to be reflected in cardiac variability, this paper will rely in particular on studies using fetal heart rate variability (fHRV) to monitor the continued growth and health of both animal and human fetuses. In fact, fHRV is a non-invasive marker whose changes have been associated with ANS development, vagal modulation, systemic and neurological inflammatory reactions, and even fetal distress during labor.

Prospective Validation of the Preschool Confusion Assessment Method for the ICU to Screen for Delirium in Infants Less Than 6 Months Old

OBJECTIVES

ICU delirium is a predictor of greater morbidity and higher mortality in the pediatric population. The diagnostic obstacles and validity of delirium monitoring among neonates and young infants have yet to be fully delineated. We sought to validate the Preschool Confusion Assessment Method for the ICU in neonates and young infants and determine delirium prevalence in this young population.

DESIGN

Prospective cohort study to validate the Preschool Confusion Assessment Method for the ICU for the assessment of ICU delirium in neonates and young infants compared with the reference standard, Child and Adolescent Psychiatry.

SETTING

Tertiary medical center PICU, including medical, surgical, and cardiac patients.

PARTICIPANTS

Infants less than 6 months old admitted to the PICU regardless of admission diagnosis.

MEASUREMENTS AND MAIN RESULTS

We enrolled 49 patients with a median age of 1.8 months (interquartile range, 0.7-4.1 mo), 82% requiring mechanical ventilation. Enrolled patients were assessed for delirium in blinded-fashion by the research team using the Preschool Confusion Assessment Method for the ICU and independently assessed by the psychiatry reference rater using Diagnostic and Statistical Manual of Mental Disorders-5 criteria. A total of 189 paired assessments were completed, and the Preschool Confusion Assessment Method for the ICU performed with a sensitivity of 95% (95% CI, 89-100%), specificity of 81% (68-90%), "negative and positive predictive values" of 97% (94-100%) and 69% (55-79%), respectively, compared with the reference rater. Delirium prevalence was 47%, with higher rates of 61% observed among neonates (< 1 mo old) and 39% among infants 1-6 months old.

CONCLUSIONS

The Preschool Confusion Assessment Method for the ICU is a valid screening tool for delirium monitoring in infants less than 6 months old. Delirium screening was feasible in this population despite evolving neurocognition and arousal architecture. ICU delirium was prevalent among infants. The consequence of acute brain dysfunction during crucial neurocognitive development remains unclear. Future studies are necessary to determine the long-term impact of ICU delirium and strategies to reduce associated harm in critically ill infants.

Association Between Sleep Duration and Intelligence Quotient in 6-Year-Old Children

BACKGROUND

Sufficient sleep during childhood is important for cognitive functions such as learning and successful school performance. This study aimed to investigate the effects of sleep duration on the intelligence quotient (IQ) of 6-year-old children and aimed to analyze whether these effects differed by sex.

METHODS

The IQ of 538 6-year-old Korean participants from the cohort study, "The Environment and Development of Children," was measured during follow-up using the Korean Educational Developmental Institute's Wechsler Intelligence Scale for Children. The total, verbal, and performance IQ scores were evaluated. The relationship between sleep duration and IQ scores after adjusting for maternal age, maternal educational level, maternal occupation, maternal IQ, exposure to secondhand smoking, gestational age, and monthly age and birth season was also assessed.

RESULTS

Longer sleep duration was significantly associated with improved verbal IQ measures (β 0.55; p value 0.030). After stratifying participants by sex, a significant association was observed between sleep duration and total, verbal, and performance IQ scores in boys (total IQ 2.49, p value 0.012; verbal IQ 0.75, p value: 0.037; performance IQ 0.73, p value 0.048), but not in girls.

CONCLUSIONS

The results indicated that only boys show a significant association between IQ scores and sleep duration. These findings support the hypothesis that sleep duration is associated with IQ, in a sex dependent manner. Future studies are needed for a thorough evaluation of the connection between sleep duration and health outcome in young children.

Preterm infants with severe brain injury demonstrate unstable physiological responses during maternal singing with music therapy: a randomized controlled study

Preterm infants with severe brain injury are at high risk for poor outcomes and, therefore, may benefit from developmental care modalities such as music therapy (MT). In this prospective, randomized intervention, preterm infants with severe brain injury (grade 3 or 4 intraventricular hemorrhage or periventricular leukomalacia) who underwent skin-to-skin contact (SSC) with or without maternal singing during MT were evaluated for physiological responses, including autonomic nervous system stability (low frequency (LF)/high frequency (HF) power), heart rate, respiratory rate, oxygen saturation, and behavioral state. Maternal anxiety state and physiological data were also evaluated. A total of 35 preterm infants with severe brain injuries were included in the study analysis. Higher mean ± standard deviation (SD) LF/HF ratio (1.8 ± 0.7 vs. 1.1 ± 0.25, p = 0.01), higher mean ± SD heart rate (145 ± 15 vs. 132 ± 12 beats per minute, p = 0.04), higher median (interquartile range) infant behavioral state (NIDCAP manual for naturalistic observation and the Brazelton Neonatal Behavioral Assessment) score (3 (2-5) vs. 1 (1-3), p = 0.03), and higher mean ± SD maternal anxiety (state-trait anxiety inventory) score (39.1 ± 10.4 vs. 31.5 ± 7.3, p = 0.04) were documented in SSC combined with maternal singing during MT, as compared to SSC alone.Conclusion: Maternal singing during MT for preterm infants with severe brain injury induces physiological and behavioral instability and increases maternal anxiety during NICU hospitalization. A unique MT intervention should be designed for preterm infants with severe brain injury and their mothers. What is Known: • Preterm infants with severe brain injury are at high risk for poor outcomes. • Music therapy benefits brain development of preterm infants without severe brain injury, however it is unknown whether maternal singing during music therapy for preterm infants with severe brain injury is beneficial. What is New: • Maternal singing during music therapy for preterm infants with severe brain injury induces physiological and behavioral instability and increases maternal anxiety during NICU hospitalization. • A unique music therapy intervention should be designed for preterm infants with severe brain injury and their mothers.

Behavioral-state development and sleep-state differentiation during early ontogenesis

Sleep is a key process in neurodevelopment and essential for the maturation of fundamental brain functions. Premature birth can disturb the initial steps of sleep maturation, which may contribute to the impairment of neurodevelopment. It is thus fundamental to understand the maturation of the various sleep states and the quality of cerebral function in each vigilance state, as well as the development of sleep cyclicity, in at-risk neonatal infants, particularly those born premature. The objective of this review is to provide a precise description of sleep states and cycles and their rhythmic organization in premature and term newborns according to their gestational age. Technical aspects of polysomnography, which requires a high level of expertise in neonates, are also described. Principles of the visual interpretation of polysomnography, including the simultaneous analysis of behavioral (spontaneous motricity and eye movements), polysomnographic parameters (electro-oculogram, electrocardiogram, respiration), and electroencephalography patterns are presented. The neurophysiology of sleep ontogenesis and its interaction with brain maturation are discussed, highlighting the crucial role of sleep states and their duration in premature newborns. In particular, the involvement of myoclonic twitches in functional connectivity in sensorimotor development is discussed. Indeed, sleep quality, determined by combined polysomnographic parameters, reflects either normal or pathological developmental processes during the neonatal period. The fundamental place of neurophysiological explorations in the early detection of sleep disorders is discussed, as well as their potential consequences on neurodevelopmental care to improve the prevention of neurodevelopmental impairment.

Comparison of sleep problems between term and preterm born preschool children

OBJECTIVES

Sleep disorders are common problems among all age groups. If sleep problems detected in childhood are not resolved successfully, they become sleep disorders and a chronic state. In this study, we aimed to compare sleep problems between preterm-born and term-born preschool-age children.

METHODS

In the cross-sectional study, children were grouped according to whether they were born preterm or at term. The preterm group included 137 children aged four to six years. The control group comprised 145 age-matched term-born preschool children. The prenatal, natal, demographical, and clinical characteristics of preterm- and term-born preschool-age children were compared. The Children's Sleep Habits Questionnaire (CSHQ) was used to identify sleep problems. The total score and subscores of the CSHQ were compared between the groups.

RESULTS

The percentage of gastroesophageal reflux (GER) symptoms and obstructive sleep apnea (OSA) symptoms were significantly higher in the preterm group. According to the cutoff point of the CSHQ, 97 children in the preterm group (70.8%) and 88 children in the control group (60.7%) had a sleep disorder. The total score of the CSHQ was significantly higher in the preterm group compared with the control group; however, the scores of the subscales were similar between the groups. In the regression analysis, a significant association was found between being born preterm and having sleep disorder (β = 0.308, OR = 1.36, p = 0.04).

CONCLUSIONS

Our study reported a high percentage of sleep problems in preterm-born preschool children. We suggest that prematurity is associated with sleep problems even if the etiology of sleep problems is heterogeneous. Symptoms regarding GER and OAS should be investigated, and precautions, such as prohibiting maternal cigarette smoking, should be taken in preterm infants.

Impact of prematurity on neurodevelopment

The consequences of prematurity on brain functional development are numerous and diverse, and impact all brain functions at different levels. Prematurity occurs between 22 and 36 weeks of gestation. This period is marked by extreme dynamics in the physiologic maturation, structural, and functional processes. These different processes appear sequentially or simultaneously. They are dependent on genetic and/or environmental factors. Disturbance of these processes or of the fine-tuning between them, when caring for premature children, is likely to induce disturbances in the structural and functional development of the immature neural networks. These will appear as impairments in learning skills progress and are likely to have a lasting impact on the development of children born prematurely. The level of severity depends on the initial alteration, whether structural or functional. In this chapter, after having briefly reviewed the neurodevelopmental, structural, and functional processes, we describe, in a nonexhaustive manner, the impact of prematurity on the different brain, motor, sensory, and cognitive functions.