Autism in Toddlers Born Very Preterm

Screening preterm-born infants for autistic traits may help to identify social communication difficulties at five years of age

AIM

This study compared neurodevelopmental screening questionnaires completed when preterm-born children reached 2 years of corrected age with social communication skills at 5.5 years of age.

METHODS

Eligible subjects were born in 2011 at 24-34 weeks of gestation, participated in a French population-based epidemiological study and were free of motor and sensory impairment at 2 years of corrected age. The Ages and Stages Questionnaire (ASQ) and the Modified Checklist for Autism in Toddlers (M-CHAT) were used at 2 years and the Social Communication Questionnaire (SCQ) at 5.5 years of age.

RESULTS

We focused on 2119 children. At 2 years of corrected age, the M-CHAT showed autistic traits in 20.7%, 18.5% and 18.2% of the children born at 24-26, 27-31 and 32-34 weeks of gestation, respectively (p = 0.7). At 5.5 years of age, 12.6%, 12.7% and 9.6% risked social communication difficulties, with an SCQ score ≥90th percentile (p = 0.2). A positive M-CHAT score at 2 years was associated with higher risks of social communication difficulties at 5.5 years of age (odds ratio 3.46, 95% confidence interval 2.04-5.86, p < 0.001). Stratifying ASQ scores produced similar results.

CONCLUSION

Using parental neurodevelopmental screening questionnaires for preterm-born children helped to identify the risk of later social communication difficulties.

Subjective experience of parent-child relationship in adolescents with congenital heart disease: A qualitative study

PURPOSE

To explore the parent-child relationship through the subjective experience of adolescents with congenital heart disease (CHD).

DESIGN AND METHODS

A descriptive phenomenology approach was adopted. Twelve adolescents aged from 12 to 18 years with CHD were recruited from the pediatric cardiology clinics at two medical centers in Taiwan. Data were collected through in-depth interviews. Data were analyzed using Colaizzi's phenomenological analysis method, and results were reported in accordance with the Consolidated Criteria for Reporting Qualitative Research guidelines.

RESULTS

The experiences of the adolescents with CHD revealed five themes: 1. the enhancement of self-worth through parents' love; 2. the importance of parental support in desperate situations; 3. the development of a sense of security through mutual understanding; 4. growth under parental expectations; and 5. parental overcontrol disguised as love.

CONCLUSIONS

The parent-child relationship encompasses both positive and negative experiences. Adolescents prioritize their relationship with parents over that with peers.

PRACTICE IMPLICATIONS

Nurses caring for adolescents with CHD can improve care by recognizing the influence of parental love, support in challenges, mutual understanding, parental expectations, and potential negative consequences of overcontrol. This insight guides effective guidance for adolescents, enhancing parent-child interactions and overall well-being.

Nutraceuticals in Psychiatric Disorders: A Systematic Review

Correct nutrition and diet are directly correlated with mental health, functions of the immune system, and gut microbiota composition. Diets with a high content of some nutrients, such as fibers, phytochemicals, and short-chain fatty acids (omega-3 fatty acids), seem to have an anti-inflammatory and protective action on the nervous system. Among nutraceuticals, supplementation of probiotics and omega-3 fatty acids plays a role in improving symptoms of several mental disorders. In this review, we collect data on the efficacy of nutraceuticals in patients with schizophrenia, autism spectrum disorders, major depression, bipolar disorder, and personality disorders. This narrative review aims to provide an overview of recent evidence obtained on this topic, pointing out the direction for future research.

Prenatal and postnatal exposure to heavy metals in PM2.5 and autism spectrum disorder

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders, and its incidence is increasing over time. Although several environmental factors have been suspected to be risk factors for ASD, studies on the effects of airborne heavy metals on newly developed ASD are still limited. We conducted a large birth cohort study of 168,062 live term births in Taichung during 2004-2011 to assess the association of heavy metals in particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5) with ASD, and identify sensitive time windows during prenatal and postnatal periods. Heavy metals, including arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in PM2.5, were estimated using the Weather Research and Forecasting/Chem (WRF/Chem), inserted from the top 75 emission sources for the module. The association between childhood ASD and 4 metals were analyzed from pregnancy to 9 months after birth. The Cox proportional hazard model with a distributed lag nonlinear model (DLNM) was used to estimate the association between heavy metals in PM2.5 and ASD. We identified 666 incident ASD cases in 168,062 participants. A positive association between Hg and ASD was found at 9 months after birth (Hazard Ratio: 1.63; 95% CI: 1.13-2.36). According to the DLNM, there was an increased risk of exposure to Hg during 10-25 weeks after birth, and decreased risk of exposure to Hg during gestational weeks 4-6. Exposure to As and Hg on the risk of ASD were significantly stronger in low birth weight infants (<2500 g) than in those of birth weight ≥2500 g during postnatal period. Postnatal exposure to Hg in PM2.5 may associate with increased ASD incidence. Infants with low birth weight and exposure to As and Hg in PM2.5 are more likely to develop ASD.

The gaze characteristics in preterm children: The appropriate timing for an eye-tracking tool

BACKGROUND

An objective screening tool for autism spectrum disorder (ASD), also known as an eye-tracking tool, assesses the patient's abnormal gaze patterns and detects the risk of ASD. As this tool is generally used for children born at term, this study aimed to clarify the appropriate timing for using the tool for preterm children, factors that influence the timing, and evaluate their gaze characteristics using the Gazefinder®.

METHOD

In 90 preterm children, a total of 125 eye-tracking tasks were completed and analyzed in 3-6, 7-9, 10-12, 13-18, and 19-32 months of corrected age (CA). The Gazefinder® was used to compare the mean fixation time percentage (MFP) in each CA and evaluate the gaze patterns. Perinatal factors associated with low MFP were also analyzed.

RESULTS

Only 50% of the children scored ≥70% MFP at 3-6 months of CA. The MFP increased significantly after 7 months of CA (p = 0.0003), reached 90% at 13-18 months, and 100% at 19-32 months of CA. Chronic lung disease (CLD) was a clinical factor associated with low MFP (p = 0.036). Preterm children gazed more at eyes but gazed at mouths when the mouth moved.

CONCLUSION

It is necessary for preterm children to begin using Gazefinder® atleast at ≥13 months of age, especially those complicated with CLD. Preterm children prefer gazing at social information just as typically developing children.

Dysbiosis in Gut Microbiota in Children Born Preterm Who Developed Autism Spectrum Disorder: A Pilot Study

The gut microbiota was reported to differ between children with autism spectrum disorder (ASD) and typically developing (TD) children, and dysbiosis of the gut microbiota in preterm infants is common. Here, we explored the characteristics of gut microbiota in children born preterm with ASD. We performed 16S rRNA gene sequencing using stool samples from ASD children born preterm and TD children born preterm. Alpha diversity was significantly greater in the ASD group. A comparison of beta diversity showed different clusters. Linear discriminant analysis effect size analysis revealed significantly more Firmicutes in the ASD group compared with the TD group. In conclusion, the gut microbiota in children born preterm differs between children with ASD and TD.

A Comparison of the Clinical Presentation of Preterm Birth and Autism Spectrum Disorder: Commonalities and Distinctions in Children Under 3

Premature infants and infants later diagnosed with autism spectrum disorder (ASD) share many commonalities in clinical presentations. However, prematurity and ASD also have differences in clinical presentation. These overlapping phenotypes can lead to misdiagnoses of ASD or missing a diagnosis of ASD in preterm infants. We document these commonalities and differences in various developmental domains with the hope of aiding in the accurate early detection of ASD and timely intervention implementation in children born premature. Given the degree of similarities in presentation, evidence-based interventions designed specifically for preterm toddlers or toddlers with ASD may ultimately aid both populations.

Prevalence of autism spectrum disorder among Saudi children between 2 and 4 years old in Riyadh

OBJECTIVES

We aimed to estimate the prevalence of autism spectrum disorder between 2 and 4 years old in Riyadh, Saudi Arabi Methods: A cross-sectional study was conducted among Saudi children aged 2-4 years between December 2017 and March 2018 at five different hospitals in Riyadh.

RESULTS

A Total of 398 children were included. The prevalence of ASD was estimated to be (2.51%, 1:40, 25 per 1000)), with a male to female ratio of 3:1.

CONCLUSION

The estimated high prevalence rate of ASD is close to recent trends in international studies. Future population-based studies are required.

Cognitive performance during adulthood in a rat model of neonatal diffuse white matter injury

RATIONALE

Infants born prematurely risk developing diffuse white matter injury (WMI), which is associated with impaired cognitive functioning and an increased risk of autism spectrum disorder. Recently, our rat model of preterm diffuse WMI induced by combined fetal inflammation and postnatal hypoxia showed impaired motor performance, anxiety-like behaviour and autism-like behaviour in juvenile rats, especially males. Immunohistochemistry showed delayed myelination in the sensory cortex and impaired oligodendrocyte differentiation.

OBJECTIVE

To assess long-term cognitive deficits in this double-hit rat model of diffuse WMI, animals were screened on impulsivity, attention and cognitive flexibility in adulthood using the 5-choice serial reaction time task (5CSRTT) and a probabilistic reversal learning task, tests that require a proper functioning prefrontal cortex. Thereafter, myelination deficits were evaluated by immunofluorescent staining in adulthood.

RESULTS

Overall, little effect of WMI or sex was found in the cognitive tasks. WMI animals showed subtle differences in performance in the 5CSRTT. Manipulating 5CSRTT parameters resulted in performance patterns previously seen in the literature. Sex differences were found in perseverative responses and omitted trials: female WMI rats seem to be less flexible in the 5CSRTT but not in the reversal learning task. Males collected rewards faster in the probabilistic reversal learning task. These findings are explained by temporally rather than permanently affected myelination and by the absence of extensive injury to prefrontal cortical subregions, confirmed by immunofluorescent staining in both adolescence and adulthood.

CONCLUSION

This rat model of preterm WMI does not lead to long-term cognitive deficits as observed in prematurely born human infants.

Diagnostic rate of autism spectrum disorder in a high-survival cohort of children born very preterm: A cross-sectional study

To investigate the diagnostic rate of autism spectrum disorder (ASD) in a high-survival cohort of very preterm children, 77 infants born very preterm (<32 weeks of gestation) were assessed at age 4-6 years old using the Autism Diagnostic Observation Schedule, 2nd edition (ADOS-2) and the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). Sixteen children (20.8%) were classified as both DSM-5-positive ASD and ADOS-2-identified "autism," which were defined as confirmed ASD in this study. Our result suggests that the prevalence of ASD in very preterm children might be much higher than reported in previous studies when all children were individually evaluated. Further studies in a large sample are required to clarify the true risk of ASD in preterm birth.

The prevalence and profile of autism in individuals born preterm: a systematic review and meta-analysis

INTRODUCTION

Preterm birth (<37 weeks) adversely affects development in behavioural, cognitive and mental health domains. Heightened rates of autism are identified in preterm populations, indicating that prematurity may confer an increased likelihood of adverse neurodevelopmental outcomes. The present meta-analysis aims to synthesise existing literature and calculate pooled prevalence estimates for rates of autism characteristics in preterm populations.

METHODS

Search terms were generated from inspection of relevant high-impact papers and a recent meta-analysis. Five databases were searched from database creation until December 2020 with PRISMA guidelines followed throughout.

RESULTS

10,900 papers were retrieved, with 52 papers included in the final analyses, further classified by assessment method (screening tools N=30, diagnostic assessment N=29). Pooled prevalence estimates for autism in preterm samples was 20% when using screening tools and 6% when using diagnostic assessments. The odds of an autism diagnosis were 3.3 times higher in individuals born preterm than in the general population.

CONCLUSIONS

The pooled prevalence estimate of autism characteristics in individuals born preterm is considerably higher than in the general population. Findings highlight the clinical need to provide further monitoring and support for individuals born preterm.

Genome-wide association study identifies a novel maternal gene × stress interaction associated with spontaneous preterm birth

BACKGROUND

Maternal stress is potentially a modifiable risk factor for spontaneous preterm birth (sPTB). However, epidemiologic findings on the maternal stress-sPTB relationship have been inconsistent.

METHODS

To investigate whether the maternal stress-sPTB associations may be modified by genetic susceptibility, we performed genome-wide gene × stress interaction analyses in 1490 African-American women from the Boston Birth cohort who delivered term (n = 1033) or preterm (n = 457) infants. Genotyping was performed using Illumina HumanOmni 2.5 array. Replication was performed using data from the NICHD genomic and Proteomic Network (GPN) for PTB research.

RESULTS

rs35331017, a T-allele insertion/deletion polymorphism in the protein-tyrosine phosphatase receptor Type D (PTPRD) gene, was the top hit that interacted significantly with maternal lifetime stress on risk of sPTB (P_G × E = 4.7 × 10^-8). We revealed a dose-responsive association between degree of stress and risk of sPTB in mothers carrying the insertion/insertion genotype, but an inverse association was observed in mothers carrying the heterozygous or deletion/deletion genotypes. This interaction was replicated in African-American (P_G × E = 0.088) and Caucasian mothers (P_G × E = 0.023) from the GPN study.

CONCLUSION

We demonstrated a significant maternal PTPRD × stress interaction on sPTB risk. This finding, if further confirmed, may provide new insight into individual susceptibility to stress-induced sPTB.

IMPACT

This was the first preterm study to demonstrate a significant genome-wide gene-stress interaction in African Americans, specifically, PTPRD gene variants can interact with maternal perceived stress to affect risk of spontaneous preterm birth. The PTPRD × maternal stress interaction was demonstrated in African Americans and replicated in both African Americans and Caucasians from the GPN study. Our findings highlight the importance of considering genetic susceptibility in assessing the role of maternal stress on spontaneous preterm birth.

A Comparison of Children Born Preterm and Full-Term on the Autism Spectrum in a Prospective Community Sample

Introduction: Previous research suggests children diagnosed with autism spectrum disorder (ASD or “autism”) born extremely and very preterm face substantially delayed development than their peers born full-term. Further, children born preterm are proposed to show a unique behavioral phenotype, which may overlap with characteristics of autism, making it difficult to disentangle their clinical presentation. To clarify the presentation of autism in children born preterm, this study examined differences in key indicators of child development (expressive language, receptive language, fine motor, and visual reception) and characteristics of autism (social affect and repetitive, restricted behaviors).

Materials and Methods: One fifty-eight children (136 full-term, twenty-two preterm) diagnosed with autism, aged 22–34 months, were identified prospectively using the Social Attention and Communication Surveillance tools during community-based, developmental surveillance checks in the second year of life. Those identified at “high likelihood” of an autism diagnosis were administered the Mullen Scales of Early Learning and the Autism Diagnostic Observation Schedule.

Results: The children born preterm and full-term did not differ significantly in their fine motor, visual reception, expressive language, or receptive language skills. No significant differences in social affect and repetitive and restrictive behavior traits were found.

Discussion: The findings of this study differs from previous research where children diagnosed with autism born very or extremely preterm were developmentally delayed and had greater autistic traits than their term-born peers. These null findings may relate to the large proportion of children born moderate to late preterm in this sample. This study was unique in its use of a community-based, prospectively identified sample of children diagnosed with autism at an early age. It may be that children in these groups differ from clinic- and hospital-based samples, that potential differences emerge later in development, or that within the autism spectrum, children born preterm and full-term develop similarly. It was concluded that within the current sample, at 2 years of age, children diagnosed with autism born preterm are similar to their peers born full-term. Thus, when clinicians identify characteristics of autism in children born preterm, it is important to refer the child for a diagnostic assessment for autism.

Fatty Acid Supplementation and Socioemotional Outcomes: Secondary Analysis of a Randomized Trial

BACKGROUND AND OBJECTIVES

Children born preterm experience socioemotional difficulties, including increased risk of autism spectrum disorder (ASD). In this secondary analysis, we tested the effect of combined docosahexaenoic acid (DHA) and arachidonic acid (AA) supplementation during toddlerhood on caregiver-reported socioemotional outcomes of children born preterm. We hypothesized that children randomly assigned to DHA + AA would display better socioemotional outcomes compared with those randomly assigned to a placebo.

METHODS

Omega Tots was a single-site randomized, fully masked, parallel-group, placebo-controlled trial. Children (N = 377) were 10 to 16 months at enrollment, born at <35 weeks' gestation, and assigned to 180 days of daily 200-mg DHA + 200-mg AA supplementation or a placebo (400 mg corn oil). Caregivers completed the Brief Infant-Toddler Social and Emotional Assessment and the Pervasive Developmental Disorders Screening Test-II, Stage 2 at the end of the trial. Liner mixed models and log-binomial regression compared socioemotional outcomes between the DHA + AA and placebo groups.

RESULTS

Outcome data were available for 83% of children (n _treatment = 161; n _placebo = 153). Differences between DHA + AA and placebo groups on Brief Infant-Toddler Social and Emotional Assessment scores were of small magnitude (Cohen's d ≤ 0.15) and not statistically significant. Children randomly assigned to DHA + AA had a decreased risk of scoring at-risk for ASD on the Pervasive Developmental Disorders Screening Test-II, Stage 2 (21% vs 32%; risk ratio = 0.66 [95% confidence interval: 0.45 to 0.97]; risk difference = -0.11 [95% confidence interval: -0.21 to -0.01]) compared with children randomly assigned to a placebo.

CONCLUSIONS

No evidence of benefit of DHA + AA supplementation on caregiver-reported outcomes of broad socioemotional development was observed. Supplementation resulted in decreased risk of clinical concern for ASD. Further exploration in larger samples of preterm children and continued follow-up of children who received DHA + AA supplementation as they approach school age is warranted.

Effects of motion and audio-visual redundancy on upright and inverted face and feature preferences in 4-13-month old pre- and full-term NICU graduates

NICU infants are reported to have diminished social orientation and increased risk of socio-communicative disorders. In this eye tracking study, we used a preference for upright compared to inverted faces as a gauge of social interest in high medical risk full- and pre-term NICU infants. We examined the effects of facial motion and audio-visual redundancy on face and eye/mouth preferences across the first year. Upright and inverted baby faces were simultaneously presented in a paired-preference paradigm with motion and synchronized vocalization varied. NICU risk factors including birth weight, sex, and degree of CNS injury were examined. Overall, infants preferred the more socially salient upright faces, making this the first report, to our knowledge, of an upright compared to inverted face preference among high medical risk NICU infants. Infants with abnormalities on cranial ultrasound displayed lower social interest, i.e. less of a preferential interest in upright faces, when viewing static faces. However, motion selectively increased their upright face looking time to a level equal that of infants in other CNS injury groups. We also observed an age-related sex effect suggesting higher risk in NICU males. Females increased their attention to the mouth in upright faces across the first year, especially between 7-10 months, but males did not. Although vocalization increased diffuse attention toward the screen, contrary to our predictions, there was no evidence that the audio-visual redundancy embodied in a vocalizing face focused additional attention on upright faces or mouths. This unexpected result may suggest a vulnerability in response to talking faces among NICU infants that could potentially affect later verbal and socio-communicative development.

Gestational Age, Perinatal Characteristics, and Autism Spectrum Disorder: A Birth Cohort Study

OBJECTIVE

To determine how gestational age relates to research-identified autism spectrum disorder (ASD-R) in the context of perinatal risk factors.

STUDY DESIGN

This is a population-based cohort study using the 1994-2000 Olmsted County Birth Cohort. Children included were born and remained in Olmsted County after age 3 years. ASD-R status was determined from signs and symptoms abstracted from medical and educational records. Cox proportional hazards models were fit to identify associations between perinatal characteristics and ASD-R.

RESULTS

The incidence of preterm birth (<37 weeks' gestation) was 8.6% among 7876 children. The cumulative incidence of ASD-R was 3.8% (95% CI 3.3-4.2) at 21 years of age. Compared with children born at full term, the risk of ASD-R appeared to be increased for children born preterm with unadjusted hazard ratios (HRs) of 2.62 (95% CI 0.65-10.57), 1.68 (95% CI 0.54-5.29), and 1.60 (95% CI 1.06-2.40) for children born extremely preterm, very preterm, and moderate-to-late preterm, respectively. In a multivariable model adjusted for perinatal characteristics, the associations were attenuated with adjusted HRs of 1.75 (95% CI 0.41-7.40), 1.24 (95% CI 0.38-4.01), and 1.42 (95% CI 0.93-2.15), for children born extremely preterm, very preterm, and moderate-to-late preterm, respectively. Among children with maternal history available (N = 6851), maternal psychiatric disorder was associated with ASD-R (adjusted HR 1.73, 95% CI 1.24-2.42).

CONCLUSIONS

The increased risk of ASD-R among children born preterm relative to children born full term was attenuated by infant and maternal characteristics.

Neonatal follow-up programs in Canada: A national survey

Background

A 2006 Canadian survey showed a large variability in neonatal follow-up practices. In 2010, all 26 tertiary level Neonatal Follow-Up clinics joined the Canadian Neonatal Follow-Up Network (CNFUN) and agreed to implement a standardized assessment (including the Bayley Scales of Infant and Toddler Development-III (Bayley-III) at 18 months corrected age for children born < 29 weeks' gestation. It is unknown whether the variability in follow-up practices lessened as a result.

Objectives

To describe the current status of neonatal follow-up services in Canada and changes over time.

Methods

A comprehensive online survey was sent to all tertiary level CNFUN Follow-up programs. Questions were based on previous survey results, current literature, and investigator expertise and consensus.

Results

Respondents included 23 of 26 (88%) CNFUN programs. All sites provide neurodevelopmental screening and referrals in a multidisciplinary setting with variations in staffing. CNFUN programs vary with most offering five to seven visits. Since 2006, assessments at 18 months CA increased from 84% to 91% of sites, Bayley-III use increased from 21% to 74% (P=0.001) and eligibility for follow-up was expanded for children with stroke, congenital diaphragmatic hernia and select anomalies detected in utero. Audit data is collected by > 80% of tertiary programs.

Conclusion

Care became more consistent after CNFUN; 18-month assessments and Bayley-III use increased significantly. However, marked variability in follow-up practices persists.

Multidimensional Developments and Free-Play Movement Tracking in 30- to 36-Month-Old Toddlers With Autism Spectrum Disorder Who Were Full Term

BACKGROUND

Few studies have investigated multidimensional developments and free-play movement performance in toddlers with an early diagnosis of autism spectrum disorder (ASD).

OBJECTIVE

This study compared cognitive, motor, and behavioral developments and free-play movement performance in toddlers with ASD who were full term (FT-ASD), toddlers who were full term and are typically developing (FT-TD), and toddlers who were born preterm and had a very low birth weight (VLBW-PT).

DESIGN

This was a prospective cross-sectional study.

METHODS

Forty-five 30- to 36-month-old age-matched toddlers were recruited and divided into FT-ASD, FT-TD, and VLBW-PT groups. Their developments were examined using the Mullen Scales of Early Learning; the Peabody Developmental Motor Scales, Second Edition; the Child Behavior Checklist for Ages 1.5 to 5; and the Repetitive Behavior Scale-Revised. In addition, the toddlers' free-play movements were tracked in laboratory settings using an automatic movement tracking system.

RESULTS

Toddlers with FT-ASD exhibited lower cognitive and motor scores and a higher degree of behavioral problems compared with toddlers with FT-TD or VLBW-PT. Furthermore, the movement tracking data in a free-play setting revealed that toddlers with FT-ASD displayed a higher degree of turning velocity, a higher moving time, and a higher frequency of moving toward the peripheral region compared with toddlers with FT-TD or VLBW-PT. Moreover, several motor developmental and movement-tracking indicators were found to correlate with behavioral problems and cognitive scores in toddlers with FT-ASD.

LIMITATIONS

The study results may have been affected by the small sample size, the cross-sectional design, and tracking only the whole body without subtle movements or segmental motions.

CONCLUSIONS

The findings suggest varied aspects of co-occurring developmental conditions and movement-based problems in toddlers with FT-ASD. Using standardized and sensitive measures for the early assessment of perceptuo-motor impairments is necessary for timely early intervention for such toddlers.

Risk for ASD in Preterm Infants: A Three-Year Follow-Up Study

Background

The aim of this study was to examine the long-term risk for autism spectrum disorders (ASD) in individuals who are born preterm and full-term using both observational instruments and parental reports. Neonatal risk factors and developmental characteristics associated with ASD risk were also examined.

Method

Participants included 110 preterm children (born at a gestational age of ≤ 34 weeks) and 39 full-term children assessed at ages 18, 24, and 36 months. The Autism Diagnostic Observation Schedule, the Modified Checklist for Autism in Toddlers, the Autism Diagnostic Interview-Revised, the Social Communication Questionnaire, and the Mullen Scales of Early Learning were administered.

Results and Conclusions

The long-term risk for ASD was higher when parental reports were employed compared to observational instruments. At 18 and 24 months, a higher long-term risk for ASD was found for preterm children compared to full-term children. At 36 months, only one preterm child and one full-term child met the cutoff for ASD based on the ADOS, yet clinical judgment and parental reports supported an ASD diagnosis for the preterm child only. Earlier gestational age and lower general developmental abilities were associated with elevated ASD risk among preterm children.

Prevalence of Autism Spectrum Disorder in Preterm Infants: A Meta-analysis

CONTEXT

Evidence is emerging that preterm infants are at risk for autism spectrum disorder (ASD).

OBJECTIVES

To conduct a systematic review and meta-analysis to estimate the prevalence of ASD in preterm infants.

DATA SOURCES

Medline (via PubMed and Ovid), Embase, PsycINFO, and relevant conference proceedings were searched in May 2017.

STUDY SELECTION

Original studies in which researchers report on the prevalence of ASD using diagnostic tests in children born preterm were included. Studies in which researchers used only ASD screening tools were excluded.

DATA EXTRACTION

Relevant data were extracted independently by 3 authors.

RESULTS

Researchers in a total of 18 studies (3366 preterm infants) used ASD diagnostic tools. The median gestation, birth weight, and age at assessment were 28.0 weeks (range: 25.1-31.3 weeks), 1055 g (range: 719-1565 g), and 5.7 years (range: 1.5-21 years), respectively. Meta-analysis revealed that the overall prevalence rate for ASD was 7% (95% confidence interval: 4% to 9%). The funnel plot and Egger's test revealed that there was probably no evidence of publication bias.

LIMITATIONS

The limitations were significant heterogeneity and a lack of studies from middle- and low-income countries.

CONCLUSIONS

The prevalence of ASD is significantly high in the preterm population. Adequate resources are needed to improve the outcomes of these children.

What Are We Measuring as Outcome? Looking Beyond Neurodevelopmental Impairment

Outcomes of neonatal intensive care unit (NICU) graduates have been categorized by rates of neurodevelopmental impairment at 2 years old. Although useful as metrics for research, these early childhood assessments may underestimate or overestimate later functional capabilities. Often overlooked are less severe but more prevalent neurobehavioral dysfunctions seen later in childhood, and chronic health concerns that may impact the child's quality of life (QoL). Comprehensive NICU follow-up should include measures of less severe cognitive/learning delays, physical/mental well-being, and the promotion of resilience in children and families. Studies are needed to identify QoL measures that will optimize children's assessments and outcomes.

Biological and Social Influences on the Neurodevelopmental Outcomes of Preterm Infants

Although very preterm birth and very low birthweight are recognized risk factors for longer term developmental difficulties, there is a wide spectrum of outcomes for children and adolescents born preterm. Biological and social variables have the potential to explain this variability. Although current understanding of these influences and how they interact is incomplete, perinatal factors are related to permanent neurosensory impairments such as cerebral palsy, blindness, and deafness. Cognitive and academic outcomes are variably associated with biological and social variables across development, and the most robust correlates of behavior and mental health difficulties include early behavioral problems and family influences.

Screening Accuracy of the Brief Infant Toddler Social-Emotional Assessment to Identify Autism Spectrum Disorder in Toddlers Born at Less Than 30 Weeks' Gestation

Despite the higher prevalence of autism spectrum disorder (ASD) in children born preterm, valid screening tools for use in preterm populations are lacking. We aimed to evaluate the screening accuracy of the Brief Infant Toddler Social-Emotional Assessment (BITSEA) and to compare it to the Pervasive Developmental Disorders Screening Test-II, Stage 2, Developmental Clinic Screener (PDDST-II-DCS) in identifying ASD diagnosis in toddlers born at < 30 weeks' gestation. Caregivers (94% mothers) of 555 children completed questionnaires (BITSEA, PDDST-II-DCS, socio-demographics) when the children (58% male) were 18-36 months. Medical charts were abstracted 3.5 years later and showed that 4% (n = 24) of children had an ASD diagnosis. BITSEA competence (sensitivity = .74; specificity = .76) and ASD (sensitivity = .70; specificity = .73) subscales demonstrated better accuracy in identifying ASD compared to the recommended PDDST-II-DCS cut-score (sensitivity = .73; specificity = .64), specifically as it related to specificity. Additional studies are needed in other preterm populations to replicate these findings.

Attention deficit hyperactivity disorder and autism spectrum disorder symptoms in school-age children born very preterm

BACKGROUND

Very preterm (VP) children face a broad range of neurodevelopmental sequelae, including behavioral problems.

AIM

To investigate prevalence, pervasiveness and co-occurrence of symptoms of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in school-age children born very preterm.

METHODS

Using questionnaire and diagnostic interview data, parent and teacher reported symptoms of ADHD and ASD of 57 VP-children (mean age = 9.2 years) were compared with 57 gender and age matched full-term children using t-tests. Intra-class correlation coefficients quantified parent-teacher agreement. Correlation analysis investigated co-occurrence of ADHD/ASD symptoms. ADHD/ASD measures were aggregated using principal component analysis. Regression analyses investigated the contribution of perinatal risk factors, sex and SES to ADHD/ASD symptoms.

RESULTS

VP-children showed higher levels of parent and teacher reported attention problems, social impairment and compromised communication skills. Fair to strong agreement was found between parent and teacher reported ADHD and ASD symptoms, indicating pervasiveness of observed difficulties. Co-occurrence of ADHD and ASD symptoms in VP-children was found. Lower gestational age was associated with higher ADHD and ASD symptom levels, male sex with higher ADHD symptom levels and lower SES with higher ASD symptom levels.

CONCLUSION

School-age VP-children show higher levels of ADHD and ASD symptoms, and attention, socialization and communication difficulties in particular. Routinely screening for these problems is recommended in follow-up care.

Omega-3 and -6 fatty acid supplementation and sensory processing in toddlers with ASD symptomology born preterm: A randomized controlled trial

BACKGROUND

Despite advances in the health and long-term survival of infants born preterm, they continue to face developmental challenges including higher risk for autism spectrum disorder (ASD) and atypical sensory processing patterns.

AIMS

This secondary analysis aimed to describe sensory profiles and explore effects of combined dietary docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and gamma-linolenic acid (GLA) supplementation on parent-reported sensory processing in toddlers born preterm who were exhibiting ASD symptoms.

STUDY DESIGN

90-day randomized, double blinded, placebo-controlled trial.

SUBJECTS

31 children aged 18-38months who were born at ≤29weeks' gestation.

OUTCOME MEASURE

Mixed effects regression analyses followed intent to treat and explored effects on parent-reported sensory processing measured by the Infant/Toddler Sensory Profile (ITSP).

RESULTS

Baseline ITSP scores reflected atypical sensory processing, with the majority of atypical scores falling below the mean. Sensory processing sections: auditory (above=0%, below=65%), vestibular (above=13%, below=48%), tactile (above=3%, below=35%), oral sensory (above=10%; below=26%), visual (above=10%, below=16%); sensory processing quadrants: low registration (above=3%; below=71%), sensation avoiding (above=3%; below=39%), sensory sensitivity (above=3%; below=35%), and sensation seeking (above=10%; below=19%). Twenty-eight of 31 children randomized had complete outcome data. Although not statistically significant (p=0.13), the magnitude of the effect for reduction in behaviors associated with sensory sensitivity was medium to large (effect size=0.57). No other scales reflected a similar magnitude of effect size (range: 0.10 to 0.32).

CONCLUSIONS

The findings provide support for larger randomized trials of omega fatty acid supplementation for children at risk of sensory processing difficulties, especially those born preterm.

Combined fetal inflammation and postnatal hypoxia causes myelin deficits and autism-like behavior in a rat model of diffuse white matter injury

Diffuse white matter injury (WMI) is a serious problem in extremely preterm infants, and is associated with adverse neurodevelopmental outcome, including cognitive impairments and an increased risk of autism-spectrum disorders. Important risk factors include fetal or perinatal inflammatory insults and fluctuating cerebral oxygenation. However, the exact mechanisms underlying diffuse WMI are not fully understood and no treatment options are currently available. The use of clinically relevant animal models is crucial to advance knowledge on the pathophysiology of diffuse WMI, allowing the definition of novel therapeutic targets. In the present study, we developed a multiple-hit animal model of diffuse WMI by combining fetal inflammation and postnatal hypoxia in rats. We characterized the effects on white matter development and functional outcome by immunohistochemistry, MRI and behavioral paradigms. Combined fetal inflammation and postnatal hypoxia resulted in delayed cortical myelination, microglia activation and astrogliosis at P18, together with long-term changes in oligodendrocyte maturation as observed in 10 week old animals. Furthermore, rats with WMI showed impaired motor performance, increased anxiety and signs of autism-like behavior, i.e. reduced social play behavior and increased repetitive grooming. In conclusion, the combination of fetal inflammation and postnatal hypoxia in rats induces a pattern of brain injury and functional impairments that closely resembles the clinical situation of diffuse WMI. This animal model provides the opportunity to elucidate pathophysiological mechanisms underlying WMI, and can be used to develop novel treatment options for diffuse WMI in preterm infants.

Social brain circuitry and social cognition in infants born preterm

Preterm birth is associated with an increased risk of adverse neurologic, psychiatric, and cognitive outcomes. The brain circuits involved in processing social information are critical to all of these domains, but little work has been done to examine whether and how these circuits may be especially sensitive to prematurity. This paper contains a brief summary of some of the cognitive, psychiatric, and social outcomes associated with prematurity, followed by a description of findings from the modest body of research into social-cognitive development in infants and children born preterm. Next, findings from studies of structural and functional brain development in infants born preterm are reviewed, with an eye toward the distinctive role of the brain circuits implicated in social functioning. The goal of this review is to investigate the extent to which the putative "social brain" may have particular developmental susceptibilities to the insults associated with preterm birth, and the role of early social-cognitive development in later neurodevelopmental outcomes. Much work has been done to characterize neurobehavioral outcomes in the preterm population, but future research must incorporate both brain and behavioral measures to identify early biomarkers linked to later emerging social-cognitive clinical impairment in order to guide effective, targeted intervention.

Early and long-term outcome of infants born extremely preterm

There is no question that birth at extremely low gestational ages presents a significant threat to an infant's survival, health and development. Growing evidence suggests that gestational age may be conceptualised as a continuum in which births before 28 weeks of gestation (extremely preterm: EP) represent the severe end of a spectrum of health and developmental adversity. Although comprising just 1%-2% of all births, EP deliveries pose the greatest challenge to neonatal medicine and to health, education and social services for the provision of ongoing support for survivors with additional needs. Studying the outcomes of these infants remains critical for evaluating and enhancing clinical care, planning long-term support and for advancing our understanding of the life-course consequences of immaturity at birth. Here we review literature relating to early and long-term neurodevelopmental, cognitive, behavioural and educational outcomes following EP birth focusing on key themes and considering implications for intervention.

Measuring and communicating meaningful outcomes in neonatology: A family perspective

Medium- and long-term outcomes have been collected and described among survivors of neonatal intensive care units for decades, for a number of purposes: (1) quality control within units, (2) comparisons of outcomes between NICUs, (3) clinical trials (whether an intervention improves outcomes), (4) end-of-life decision-making, (5) to better understand the effects of neonatal conditions and/or interventions on organs and/or long-term health, and finally (6) to better prepare parents for the future. However, the outcomes evaluated have been selected by investigators, based on feasibility, availability, cost, stability, and on what investigators consider to be important. Many of the routinely measured outcomes have major limitations: they may not correlate well with long-term difficulties, they may artificially divide continuous outcomes into dichotomous ones, and may have no clear relationship with quality of life and functioning of children and their families. Several investigations, such as routine term cerebral resonance imaging for preterm infants, have also not yet been shown to improve the outcome of children nor their families. In this article, the most common variables used in neonatology as well as some variables which are rarely measured but may be of equal importance for families are presented. The manner in which these outcomes are communicated to families will be examined, as well as recommendations to optimize communication with parents.

Predictive Validity of the Modified Checklist for Autism in Toddlers (M-CHAT) Born Very Preterm

OBJECTIVE

To examine the predictive validity of the Modified Checklist for Autism in Toddlers (M-CHAT) administered at age 24 months for autism spectrum disorder (ASD) diagnosed at 10 years of age in a US cohort of 827 extremely low gestational age newborns (ELGANs) followed from birth.

STUDY DESIGN

We examined the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the M-CHAT in predicting an ASD diagnosis at age 10 years based on gold standard diagnostic instruments. We then assessed how these predictive parameters were affected by sensorimotor and cognitive impairments, socioeconomic status (SES), and emotional/behavioral dysregulation at age 2 years.

RESULTS

Using standard criteria, the M-CHAT had a sensitivity of 52%, a specificity of 84%, a PPV of 20%, and an NPV of 96%. False-positive and false-negative rates were high among children with hearing and vision impairments. High false-positive rates also were associated with lower SES, motor and cognitive impairments, and emotional/behavioral dysregulation at age 2 years.

CONCLUSIONS

Among extremely preterm children with ASD, almost one-half were not correctly screened by the M-CHAT at age 2 years. Sensorimotor and cognitive impairments, SES, and emotional/behavioral dysregulation contributed significantly to M-CHAT misclassifications. Clinicians are advised to consider these factors when screening very preterm toddlers for ASD.

Recent advances in the management of infants born <1000 g

In this review, we survey some significant advances in the medical care of babies <1000 g and we highlight the development of care pathways that ensure optimal antenatal care, which is a prerequisite for good neonatal outcomes. We also suggest that the long overdue development of family integrated care will in the end prove at least as important as the recent medical advances.

Prenatal stress alters amygdala functional connectivity in preterm neonates

Exposure to prenatal and early-life stress results in alterations in neural connectivity and an increased risk for neuropsychiatric disorders. In particular, alterations in amygdala connectivity have emerged as a common effect across several recent studies. However, the impact of prenatal stress exposure on the functional organization of the amygdala has yet to be explored in the prematurely-born, a population at high risk for neuropsychiatric disorders. We test the hypothesis that preterm birth and prenatal exposure to maternal stress alter functional connectivity of the amygdala using two independent cohorts. The first cohort is used to establish the effects of preterm birth and consists of 12 very preterm neonates and 25 term controls, all without prenatal stress exposure. The second is analyzed to establish the effects of prenatal stress exposure and consists of 16 extremely preterm neonates with prenatal stress exposure and 10 extremely preterm neonates with no known prenatal stress exposure. Standard resting-state functional magnetic resonance imaging and seed connectivity methods are used. When compared to term controls, very preterm neonates show significantly reduced connectivity between the amygdala and the thalamus, the hypothalamus, the brainstem, and the insula (p < 0.05). Similarly, when compared to extremely preterm neonates without exposure to prenatal stress, extremely preterm neonates with exposure to prenatal stress show significantly less connectivity between the left amygdala and the thalamus, the hypothalamus, and the peristriate cortex (p < 0.05). Exploratory analysis of the combined cohorts suggests additive effects of prenatal stress on alterations in amygdala connectivity associated with preterm birth. Functional connectivity from the amygdala to other subcortical regions is decreased in preterm neonates compared to term controls. In addition, these data, for the first time, suggest that prenatal stress exposure amplifies these decreases.