Sleeping like a baby--does gender influence infant arousability?

Evaluating the evolution and inter-individual variability of infant functional module development from 0 to 5 yr old

The segregation and integration of infant brain networks undergo tremendous changes due to the rapid development of brain function and organization. In this paper, we introduce a novel approach utilizing Bayesian modeling to analyze the dynamic development of functional modules in infants over time. This method retains inter-individual variability and, in comparison with conventional group averaging techniques, more effectively detects modules, taking into account the stationarity of module evolution. Furthermore, we explore gender differences in module development under awake and sleep conditions by assessing modular similarities. Our results show that female infants demonstrate more distinct modular structures between these 2 conditions, possibly implying relative quiet and restful sleep compared with male infants.

Is it a Match? Yawn Contagion and Smile Mimicry in Toddlers

Automatic behavioral matching includes Rapid Facial Mimicry (RFM) and Yawn Contagion (YC) that occur when the facial expression of an individual acts as a 'mirror social releaser' and induces the same facial expression in the observer (within 1 s for RFM, and minutes for YC). Motor replication has been linked to coordination and emotional contagion, a basic form of empathy. We investigated the presence and modulating factors of Rapid Smile Mimicry (RSM) and YC in infants/toddlers from 10 to 36 months at the nursery 'Melis' (Turin, Italy). In February-May 2022, we gathered audio and/or video of all occurrences data on affiliative behaviors, smiling during play, and yawning during everyday activities. Both RSM and YC were present, as toddlers were most likely to smile (within 1 s) or yawn (within three-min) after perceiving a smile/yawn from another toddler. Sex, age, and parents' country of origin did not influence RSM and YC occurrence, probably because gonadal maturation was long to come, the age range was skewed towards the early developmental phase, and toddlers had been in the same social group for months. RSM and YC showed social modulation, thus possibly implying more than just motor resonance. Both phenomena were inversely related to affiliation levels (a social bond proxy). Because literature reports that in adults RSM and YC may increase with familiarity, our reversed result suggests that in certain toddler cohorts the same phenomena may help increase socio-emotional coordination and that the function of motoric resonance may be experience- and context-dependent.

The Changing Epidemiology of Sudden Infant Death Syndrome: A 15-Year Overview Comparing Italian and European Data

Background and Aims

Sudden Infant Death Syndrome (SIDS) represents a prominent cause of infant death in many countries. Epidemiological data has been variable over time because the related International Classification of Diseases (ICD) code is not consistent throughout countries and has changed over the years. The prevalence of SIDS is unclear, with estimates that do not reflect the number of patients who actually died from SIDS. This paper aims to assess the trend of SIDS in Italy and Europe during 2011-2018, and factors contributing to epidemiological data. Data for Italy were also integrated with an individual-level analysis over the period 2003-2018.

Methods

A two-pronged analysis was performed starting from the Italian National Institute of Statistics and experimental data. The individual characteristics of SIDS infants were detailed in association with biomedical, socioeconomic, and cultural variables.

Results

Total infant mortality has been continuously declining in Italy, from 4.15‰ in 2003 to 3.05‰ in 2018 (-26.5%) with rates significantly lower than the European average in the same period (mean Italy 3.05‰ vs. mean Europe 4.11‰). Considering only SIDS, the 28 European countries show an average value of 0.15/1000 deaths/births (2011-2018), with a decreasing temporal trend. Italy displays an average rate 75% lower (0.04/1000 births). The seasonality of the syndrome highlights a prevalence during cold months (60.7%) and no evidence of a significant effect of mother's age at birth was found. The mean age at death is prevalent in the postneonatal period. No statistically significant effects on Italian SIDS mortality have been found regarding economical, educational, and cultural aspects related to the care of infants.

Conclusion

The data suggest a likely effect of different ways of classification of SIDS-related deaths, although a different approach to the prevention campaigns could be responsible for data variability among countries. Results also suggest an urgent need to get insight into previously unexplored aspects, such as neuroanatomical, genetic, metabolic, and proteomic aspects, focusing especially on high-risk groups to further clarify the etiopathogenesis of this syndrome.

Obstructive Sleep Apnea in Pediatrics and Adolescent Women: A Systematic Review of Sex-Based Differences Between Girls and Boys

BACKGROUND/OBJECTIVES

Obstructive sleep apnea (OSA) is marked by repetitive occurrences of upper airway (UA) obstruction during sleep. Morbidities impacting the metabolic, cardiovascular (CV) and neurological systems are correlated with OSA. Only a few studies have described the existence of different characteristics depending on sex and, to date, the girl phenotype in OSA pediatrics is not well known. The objective of this systematic review is to identify the specific phenotype of OSA in pediatric and adolescent females compared to males.

METHODS

A systematic review was performed. The terms "pediatric sleep apnea" and "sex differences" were used to look for publications using PubMed, the Cochrane Library and Web of Science.

INCLUSION CRITERIA

(1) peer-reviewed journal articles written in English; (2) investigations conducted on individuals diagnosed with OSA; and (3) investigations providing information about sex differences.

EXCLUSION CRITERIA

(1) studies carried out with individuals aged 18 years and older; (2) studies involving a sample size of fewer than 10 patients; and (3) editorials, letters and case reports.

RESULTS

Fifteen studies were included and classified in sections related to sex-based differences.

CONCLUSIONS

Limited information related to sex-based OSA differences in the pediatric population exists. These differences are conditioned by hormonal status, and are minimal in the premenarcheal period. Moreover, adolescent women present a lower prevalence of obesity and craniofacial alterations, lower OSA severity related to higher UA area and earlier tonsil regression. Hyperactivity is more frequent in boys. Some studies pointed to a higher risk of high diastolic blood pressure in girls than in boys.

Sleep Disorders in Women: What Should a Gynecologist Know?

Women often face sleep disturbances during key life stages such as adolescence, pregnancy, postpartum period, and perimenopause, influenced by hormonal fluctuations and conditions like polycystic ovary syndrome (PCOS) and premenstrual syndrome (PMS). The goal is to explore women's sleep disorders as classified in the International Classification of Sleep Disorders-3 (ICSD-3). Through a literature review, this study assesses the management of sleep disorders in women, particularly focusing on the link between gynecological disease and sleep disorders. It scrutinizes landmark research in diagnosing and treating women's sleep disorders. Observations indicate that physiological changes during adolescence, pregnancy, postpartum, and perimenopause can cause sleep issues, commonly addressed by gynecologists. Conditions like PCOS and PMS are notably linked to increased sleep disorder occurrences. The conclusion underscores the importance of gynecologists' awareness of the heightened risk of sleep disturbances in women, who often present these issues during consultations.

National SIDS Trends in the United States From 2000 to 2019: A Population-Based Study on 80 Million Live Births

Sudden infant death syndrome (SIDS) is the most common cause of death for infants between 1 month and 1 year of age in the United States. The objective was to examine recent trends in SIDS in the United States, over time and by sex and race. A population-based cross-sectional study was conducted on 80 710 348 live births using data from the Center for Disease Control and Prevention's (CDC) "Birth Data" and "Mortality Multiple Cause" files from 2000 to 2019. Logistic regression examined the effects of sex and race on the risk of SIDS and examined temporal changes in risk across sex and race over the study period. Incidence of SIDS decreased from 6.3 to 3.4/10 000 births from 2000 to 2019, with an overall incidence of 4.9/10 000 births (95% confidence interval [CI] = 4.4-5.3). Male infants were at the greatest risk of SIDS as were black and American Indian infants. Although SIDS incidence decreased by sex and race over time, the decline was smaller among Hispanic and American Indian infants.

Death from Failed Protection? An Evolutionary-Developmental Theory of Sudden Infant Death Syndrome

Sudden infant death syndrome (SIDS) has been mainly described from a risk perspective, with a focus on endogenous, exogenous, and temporal risk factors that can interact to facilitate lethal outcomes. Here we discuss the limitations that this risk-based paradigm may have, using two of the major risk factors for SIDS, prone sleep position and bed-sharing, as examples. Based on a multipronged theoretical model encompassing evolutionary theory, developmental biology, and cultural mismatch theory, we conceptualize the vulnerability to SIDS as an imbalance between current physiologic-regulatory demands and current protective abilities on the part of the infant. From this understanding, SIDS appears as a developmental condition in which competencies relevant to self-protection fail to develop appropriately in the future victims. Since all of the protective resources in question are bound to emerge during normal infant development, we contend that SIDS may reflect an evolutionary mismatch situation-a constellation in which certain modern developmental influences may overextend the child's adaptive (evolutionary) repertoire. We thus argue that SIDS may be better understood if the focus on risk factors is complemented by a deeper appreciation of the protective resources that human infants acquire during their normal development. We extensively analyze this evolutionary-developmental theory against the body of epidemiological and experimental evidence in SIDS research and thereby also address the as-of-yet unresolved question of why breastfeeding may be protective against SIDS.

Vaccines and sudden infant death: An analysis of the VAERS database 1990-2019 and review of the medical literature

Although there is considerable evidence that a subset of infants has an increased risk of sudden death after receiving vaccines, health authorities eliminated "prophylactic vaccination" as an official cause of death, so medical examiners are compelled to misclassify and conceal vaccine-related fatalities under alternate cause-of-death classifications. In this paper, the Vaccine Adverse Event Reporting System (VAERS) database was analyzed to ascertain the onset interval of infant deaths post-vaccination. Of 2605 infant deaths reported to VAERS from 1990 through 2019, 58 % clustered within 3 days post-vaccination and 78.3 % occurred within 7 days post-vaccination, confirming that infant deaths tend to occur in temporal proximity to vaccine administration. The excess of deaths during these early post-vaccination periods was statistically significant (p < 0.00001). A review of the medical literature substantiates a link between vaccines and sudden unexplained infant deaths. Several theories regarding the pathogenic mechanism behind these fatal events have been proposed, including the role of inflammatory cytokines as neuromodulators in the infant medulla preceding an abnormal response to the accumulation of carbon dioxide; fatal disorganization of respiratory control induced by adjuvants that cross the blood-brain barrier; and biochemical or synergistic toxicity due to multiple vaccines administered concurrently. While the findings in this paper are not proof of an association between infant vaccines and infant deaths, they are highly suggestive of a causal relationship.

Environmental Tobacco Smoke During the Early Postnatal Period of Mice Interferes With Brain 18 F-FDG Uptake From Infancy to Early Adulthood - A Longitudinal Study

Exposure to environmental tobacco smoke (ETS) is associated with high morbidity and mortality, mainly in childhood. Our aim was to evaluate the effects of postnatal ETS exposure in the brain 2-deoxy-2-[¹⁸F]-fluoro-D-glucose (¹⁸F-FDG) uptake of mice by positron emission tomography (PET) neuroimaging in a longitudinal study. C57BL/6J mice were exposed to ETS that was generated from 3R4F cigarettes from postnatal day 3 (P3) to P14. PET analyses were performed in male and female mice during infancy (P15), adolescence (P35), and adulthood (P65). We observed that ETS exposure decreased ¹⁸F-FDG uptake in the whole brain, both left and right hemispheres, and frontal cortex in both male and female infant mice, while female infant mice exposed to ETS showed decreased ¹⁸F-FDG uptake in the cerebellum. In addition, all mice showed reduced ¹⁸F-FDG uptake in infancy, compared to adulthood in all analyzed VOIs. In adulthood, ETS exposure during the early postnatal period decreased brain ¹⁸F-FDG uptake in adult male mice in the cortex, striatum, hippocampus, cingulate cortex, and thalamus when compared to control group. ETS induced an increase in ¹⁸F-FDG uptake in adult female mice when compared to control group in the brainstem and cingulate cortex. Moreover, male ETS-exposed animals showed decreased ¹⁸F-FDG uptake when compared to female ETS-exposed in the whole brain, brainstem, cortex, left amygdala, striatum, hippocampus, cingulate cortex, basal forebrain and septum, thalamus, hypothalamus, and midbrain. The present study shows that several brain regions are vulnerable to ETS exposure during the early postnatal period and these effects on ¹⁸F-FDG uptake are observed even a long time after the last exposure. This study corroborates our previous findings, strengthening the idea that exposure to tobacco smoke in a critical period interferes with brain development of mice from late infancy to early adulthood.

The Sudden Infant Death Syndrome mechanism of death may be a non-septic hyper-dynamic shock

BACKGROUND

Sudden Infant Death Syndrome (SIDS) mechanisms of death remains obscured. SIDS' Triple Risk Model assumed coexistence of individual subtle vulnerability, critical developmental period and stressors. Prone sleeping is a major risk factor but provide no clues regarding the mechanism of death. The leading assumed mechanisms of death are either an acute respiratory crisis or arrhythmias but neither one is supported with evidence, hence both are eventually speculations. Postmortem findings do exist but are inconclusive to identify the mechanism of death. WHAT DOES THE PROPOSED HYPOTHESIS BASED ON?: 1. The stressors (suggested by the triple risk model) share a unified compensatory physiological response of decrease in systemic vascular resistant (SVR) to facilitate a compensatory increase in cardiac output (CO). 2. The cardiovascular/cardiorespiratory control of the vulnerable infant during a critical developmental period may be impaired. 3. A severe decrease in SVR is associated with hyper-dynamic state, high output failure and distributive shock.

THE HYPOTHESIS

Infant who is exposed to one or more stressors responds normally by decrease in SVR which increases CO. In normal circumstances once the needs are met both SVR and CO are stabilized on a new steady state. The incompetent cardiovascular control of the vulnerable infant fails to stabilize SVR which decreases in an uncontrolled manner. Accordingly CO increases above the needs to hyper-dynamic state, high output heart failure and hyper-dynamic shock.

CONCLUSIONS

The proposed hypothesis provides an appropriate alternative to either respiratory crises or arrhythmia though both speculations cannot be entirely excluded.

Sleep in Women Across the Life Span

There are many ways in which women experience sleep differently from men. Women contending with distinct sleep challenges respond differently to sleep disorders, as well as sleep deprivation and deficiency, and face particular health outcomes as a result of poor sleep. Idiosyncrasies, including changes that occur with the biological life cycles of menstruation, pregnancy, and menopause, make the understanding of sleep in women an important topic to study. Each phase of a woman's life, from childhood to menopause, increases the risk of sleep disturbance in unique ways that may require distinct management. Indeed, new research is unraveling novel aspects of sleep pathology in women and the fundamental role that sex hormones play in influencing sleep regulation and arousals and possibly outcomes of sleep conditions. Moreover, studies indicate that during times of hormonal change, women are at an increased risk for sleep disturbances such as poor sleep quality and sleep deprivation, as well as sleep disorders such as OSA, restless legs syndrome, and insomnia. This article reviews sleep changes in female subjects from neonatal life to menopause.

Maternal and infant factors associated with reasons for introducing solid foods

The current UK Department of Health advice is to introduce solid foods to infants at around 6 months of age, when the infant is showing signs of developmental readiness for solid foods. However, many mothers introduce solid foods before this time, and for a wide variety of reasons, some of which may not promote healthy outcomes. The aim of the current study was to examine infant and maternal characteristics associated with different reasons for introducing solid foods. Seven hundred fifty-six mothers with an infant aged 6-12 months old completed a questionnaire describing their main reason for introducing solid foods alongside demographic questions, infant weight, gender, breast/formula feeding and timing of introduction to solid foods. The majority of mothers introduced solid foods for reasons explicitly stated in the Department of Health advice as not signs of readiness for solid foods. These reasons centred on perceived infant lack of sleep, hunger or unsettled behaviour. Maternal age, education and parity, infant weight and gender and breast/formula feeding choices were all associated with reasons for introduction. A particular association was found between breastfeeding and perceiving the infant to be hungrier or needing more than milk could offer. Male infants were perceived as hungry and needing more energy than female infants. Notably, signs of readiness may be misinterpreted with some stating this reason for infants weaned prior to 16 weeks. The findings are important for those working to support and educate new parents with the introduction of solid foods in understanding the factors that might influence them.

[A prospective study of the development of nocturnal sleep patterns in infants]

OBJECTIVE

To investigate the development of nocturnal sleep pattern in infants.

METHODS

Fifty healthy full-term newborns born in Chongqing Maternal and Child Health Care Hospital were chosen for a prospective longitudinal study. A non-invasive sleep monitor, Actiwatch, was used to monitor infants' 12 sleep parameters on the 10th day, 28th day, the first Tuesday at the 2nd, 3rd, 4th, 5th, 6th, 9th and 12th month after birth, each monitoring time lasting 60 hours. All sleep parameters were analyzed by two-level mixed effect model.

RESULTS

Twenty-two boys and 25 girls completed the whole follow-up study. From birth to the 12th month after birth, the nocturnal sleep onset latency (NSOL) decreased by about 48% at 3 months of age and by 83% at 6 months of age. The nocturnal sleep efficiency (NSE%) increased from 66% to 87%, the nocturnal total sleep time (NTST) increased from 416 minutes to 517 minutes, and the longest nocturnal continuous sleeping time (L-NCST) increased from 197 minutes to 327 minutes. NSE%, NTST and L-NCST increased with age (P<0.01). The 3rd to 12th month ratios of NSE%, NTST and L-NCST were 86%, 84% and 72%, respectively, and the 6th to 12th month ratios of those were 97%, 91% and 94%, respectively. The nocturnal total wake time (NTWT) and longest nocturnal continuous waking times (L-NCWT) decreased with age (P<0.01). The decline speeds in the first half year were 5-6 times of those in the second half year after birth (P<0.05). NTST, nocturnal continuous sleeping ability and NSE% in boys were lower than those in girls (P<0.05).

CONCLUSIONS

Infantile nocturnal sleep patterns develop rapidly during the first 6 months, especially within the first 3 months after birth. Partial infantile sleep parameters are related to gender.

[A prospective study of the development of nocturnal sleep patterns in infants]

OBJECTIVE

To investigate the development of nocturnal sleep pattern in infants.

METHODS

Fifty healthy full-term newborns born in Chongqing Maternal and Child Health Care Hospital were chosen for a prospective longitudinal study. A non-invasive sleep monitor, Actiwatch, was used to monitor infants' 12 sleep parameters on the 10th day, 28th day, the first Tuesday at the 2nd, 3rd, 4th, 5th, 6th, 9th and 12th month after birth, each monitoring time lasting 60 hours. All sleep parameters were analyzed by two-level mixed effect model.

RESULTS

Twenty-two boys and 25 girls completed the whole follow-up study. From birth to the 12th month after birth, the nocturnal sleep onset latency (NSOL) decreased by about 48% at 3 months of age and by 83% at 6 months of age. The nocturnal sleep efficiency (NSE%) increased from 66% to 87%, the nocturnal total sleep time (NTST) increased from 416 minutes to 517 minutes, and the longest nocturnal continuous sleeping time (L-NCST) increased from 197 minutes to 327 minutes. NSE%, NTST and L-NCST increased with age (P<0.01). The 3rd to 12th month ratios of NSE%, NTST and L-NCST were 86%, 84% and 72%, respectively, and the 6th to 12th month ratios of those were 97%, 91% and 94%, respectively. The nocturnal total wake time (NTWT) and longest nocturnal continuous waking times (L-NCWT) decreased with age (P<0.01). The decline speeds in the first half year were 5-6 times of those in the second half year after birth (P<0.05). NTST, nocturnal continuous sleeping ability and NSE% in boys were lower than those in girls (P<0.05).

CONCLUSIONS

Infantile nocturnal sleep patterns develop rapidly during the first 6 months, especially within the first 3 months after birth. Partial infantile sleep parameters are related to gender.

Associations between infant temperament, maternal stress, and infants' sleep across the first year of life

Effects of temperament and maternal stress on infant sleep behaviors were explored longitudinally. Negative temperament was associated with sleep problems, and with longer sleep latency and night wakefulness, whereas maternal stress was associated with day sleep duration, suggesting infant and maternal characteristics affect sleep differentially.

Pacifier use does not alter sleep and spontaneous arousal patterns in healthy term-born infants

AIM

Impaired arousal from sleep has been implicated in sudden infant death syndrome (SIDS). Sleeping in the prone position is a major risk factor for SIDS. Epidemiological studies have shown that pacifier use decreases the risk of SIDS, even when infants sleep prone. We examined spontaneous arousability in infants slept prone and supine over the first 6 months of life and hypothesised that spontaneous arousals would be increased in pacifier users, particularly in the prone position.

METHODS

Healthy term infants (n = 30) were studied on three occasions over the first 6 months after birth. Spontaneous cortical arousals and subcortical activations were scored and converted into frequency per hour of sleep.

RESULTS

There was no effect of pacifier use on total time spent sleeping or awake or the number of spontaneous awakenings at any age. There was also no effect of pacifier use on the frequency or duration of the total number of spontaneous arousals or on cortical arousals and subcortical activations.

CONCLUSION

Pacifier use did not alter infant spontaneous arousability at any of the three ages studied, in either the prone or supine sleeping position. Any preventative effect of pacifiers for SIDS may be through physiological mechanisms other than increased arousability.

The physiological determinants of sudden infant death syndrome

It is well-established that environmental and biological risk factors contribute to Sudden Infant Death Syndrome (SIDS). There is also growing consensus that SIDS requires the intersection of multiple risk factors that result in the failure of an infant to overcome cardio-respiratory challenges. Thus, the critical next steps in understanding SIDS are to unravel the physiological determinants that actually cause the sudden death, to synthesize how these determinants are affected by the known risk factors, and to develop novel ideas for SIDS prevention. In this review, we will examine current and emerging perspectives related to cardio-respiratory dysfunctions in SIDS. Specifically, we will review: (1) the role of the preBötzinger complex (preBötC) as a multi-functional network that is critically involved in the failure to adequately respond to hypoxic and hypercapnic challenges; (2) the potential involvement of the preBötC in the gender and age distributions that are characteristic for SIDS; (3) the link between SIDS and prematurity; and (4) the potential relationship between SIDS, auditory function, and central chemosensitivity. Each section underscores the importance of marrying the epidemiological and pathological data to experimental data in order to understand the physiological determinants of this syndrome. We hope that a better understanding will lead to novel ways to reduce the risk to succumb to SIDS.

Post-hypoxic recovery of respiratory rhythm generation is gender dependent

The preBötzinger complex (preBötC) is a critical neuronal network for the generation of breathing. Lesioning the preBötC abolishes respiration, while when isolated in vitro, the preBötC continues to generate respiratory rhythmic activity. Although several factors influence rhythmogenesis from this network, little is known about how gender may affect preBötC function. This study examines the influence of gender on respiratory activity and in vitro rhythmogenesis from the preBötC. Recordings of respiratory activity from neonatal mice (P10-13) show that sustained post-hypoxic depression occurs with greater frequency in males compared to females. Moreover, extracellular population recordings from the preBötC in neonatal brainstem slices (P10-13) reveal that the time to the first inspiratory burst following reoxygenation (TTFB) is significantly delayed in male rhythmogenesis when compared to the female rhythms. Altering activity of ATP sensitive potassium channels (KATP) with either the agonist, diazoxide, or the antagonist, tolbutamide, eliminates differences in TTFB. By contrast, glucose supplementation improves post-hypoxic recovery of female but not male rhythmogenesis. We conclude that post-hypoxic recovery of respiration is gender dependent, which is, in part, centrally manifested at the level of the preBötC. Moreover, these findings provide potential insight into the basis of increased male vulnerability in a variety of conditions such as Sudden Infant Death Syndrome (SIDS).

Influence of hypoxia and hypercapnia on sleep state-dependent heart rate variability behavior in newborn lambs

STUDY OBJECTIVES

Although hypercapnia and/or hypoxia are frequently present during chronic lung disease of infancy and have also been implicated in sudden infant death syndrome (SIDS), their effect on cardiac autonomic regulation remains unclear. The authors' goal is to test that hypercapnia and hypoxia alter sleep-wake cycle-dependent heart rate variability (HRV) in the neonatal period.

DESIGN

Experimental study measuring HRV during sleep states in lambs randomly exposed to hypercapnia, hypoxia, or air.

SETTING

University center for perinatal research in ovines (Sherbrooke, Canada). INSERM-university research unit for signal processing (Rennes, France).

PARTICIPANTS

Six nonsedated, full-term lambs.

INTERVENTIONS

Each lamb underwent polysomnographic recordings while in a chamber flowed with either air or 21% O(2) + 5% CO(2) (hypercapnia) or 10% O(2) + 0% CO(2) (hypoxia) on day 3, 4, and 5 of postnatal age.

MEASUREMENTS AND RESULTS

Hypercapnia increased the time spent in wakefulness and hypoxia the time spent in quiet sleep (QS). The state of alertness was the major determinant of HRV characterized with linear or nonlinear methods. Compared with QS, active sleep (AS) was associated with an overall increase in HRV magnitude and short-term self-similarity and a decrease in entropy of cardiac cycle length in air. This AS-related HRV pattern persisted in hypercapnia and was even more pronounced in hypoxia.

CONCLUSION

Enhancement of AS-related sympathovagal coactivation in hypoxia, together with increased heart rate regularity, may be evidence that AS + hypoxia represent a particularly vulnerable state in early life. This should be kept in mind when deciding the optimal arterial oxygenation target in newborns and when investigating the potential involvement of hypoxia in SIDS pathogenesis.

The role of infant sleep in intergenerational transmission of trauma

INTRODUCTION

Children of parents who experienced trauma often present emotional and behavioral problems, a phenomenon named inter-generational transmission of trauma (IGTT). Combined with antenatal factors, parenting and the home environment contribute to the development and maintenance of sleep problems in children. In turn, infant sleep difficulty predicts behavioral and emotional problems later in life. The aim of this study was to investigate whether infant sleep problems predict early behavioral problems indicative of IGTT.

METHODS

184 first-time mothers (ages 18-47) participated. N=83 had a history of childhood abuse and posttraumatic stress disorder (PTSD+); 38 women reported childhood abuse but did not meet diagnostic criteria for PTSD (PTSD-); and the control group (N=63) had neither a history of abuse nor psychopathology (CON). Depression, anxiety, and sleep difficulty were assessed in the mothers at 4 months postpartum. Infant sleep was assessed using the Child Behavior Sleep Questionnaire (CSHQ). Outcome measures included the Parent Bonding Questionnaire (PBQ) at 4 months and the Child Behavior Check List (CBCL) at 18 months.

RESULTS

Infants of PTSD+ mothers scored higher on the CSHQ and had more separation anxiety around bedtime than PTSD- and CON, and the severity of their symptoms was correlated with the degree of sleep disturbance. Maternal postpartum depression symptoms mediated impaired mother-infant bonding, while infant sleep disturbance contributed independently to impaired bonding. Mother-infant bonding at 4 months predicted more behavioral problems at 18 months.

CONCLUSIONS

Infant sleep difficulties and maternal mood play independent roles in infant-mother bonding disturbance, which in turn predicts behavioral problems at 18 months.