Prevalence of autism spectrum disorder in adolescents born weighing <2000 grams

Neurodevelopmental Hypothesis about the Etiology of Autism Spectrum Disorders

Previous models or hypotheses of autism spectral disorder (ASD) failed to take into full consideration the chronological and causal developmental trajectory, leading to the emergence of diverse phenotypes through a complex interaction between individual etiologies and environmental factors. Those phenotypes include persistent deficits in social communication and social interaction (criteria A in DSM-5), and restricted, repetitive patterns of behavior, interests, or activities (criteria B in DSM-5). In this article, we proposed a domain-general model that can explain criteria in DSM-5 based on the assumption that the same etiological mechanism would trigger the various phenotypes observed in different individuals with ASD. In the model, we assumed the following joint causes as the etiology of autism: (1) Hypoplasia of the pons in the brainstem, occurring immediately following neural tube closure; and (2) Deficiency in the GABA (γ-aminobutyric acid) developmental switch during the perinatal period. Microstructural abnormalities of the pons directly affect both the structural and functional development of the brain areas strongly connected to it, especially amygdala. The impairment of GABA switch could not only lead to the deterioration of inhibitory processing in the neural network, but could also cause abnormal cytoarchitecture. We introduced a perspective that atypical development in both brain structure and function can give full explanation of diverse phenotypes and pathogenetic mechanism of ASD. Finally, we discussed about neural mechanisms underlying the phenotypic characteristics of ASD that are not described in DSM-5 but should be considered as important foundation: sleep, global precedence, categorical perception, intelligence, interoception and motor control.

Behavioral Patterns in Adolescents Born at 23 to 25 Weeks of Gestation

BACKGROUND

This study examined mental health outcomes in extremely preterm children (EPT) born at 23 to 25 weeks of gestation between 1992 and 1998 at 2 Swedish tertiary care centers that offered regional and active perinatal care to all live-born EPT infants.

METHODS

We assessed 132 (98%) of the 134 EPT survivors at 10 to 15 years of age alongside term-born controls. Behavioral and emotional problems were evaluated by using Achenbach's Child Behavior Checklist and Teacher Report Form and Conners' Parent and Teacher scales for attention-deficit/hyperactivity disorder.

RESULTS

Parents and teachers reported significantly more problems with internalizing behaviors as well as attention, social, and thought problems in EPT children than in controls, even when those with major neurodevelopmental disabilities (NDDs) were excluded. Multivariate analysis of covariance of the behavioral problems reported by parents and teachers revealed no interactions, but significant main effects emerged for group status (EPT versus control) and sex, with all effect sizes being medium to large and accounting for 8% to 14% of the variance. Compared with the controls, EPT children without NDDs had significantly increased rates of ≥90th percentile for total Conners' attention-deficit/hyperactivity disorder problem scores (parents: 40% vs 15%, odds ratio: 3.7, P < .001) (teachers: 24% vs 9%, odds ratio: 3.3, P = .005). The corresponding rates were higher in the total population.

CONCLUSIONS

EPT children with or without NDDs had behavioral problems characterized by a higher risk for anxiety and attention, social, and thought problems. These findings further strengthen the proposition that a preterm behavioral phenotype is recognizable in adolescents born EPT.

A group of very preterm children characterized by atypical gaze patterns

OBJECTIVE

Very preterm (VP) children are at risk for social difficulties, including autism spectrum disorder (ASD). This study used eye tracking to determine viewing behaviors that may reflect these difficulties.

DESIGN

The gaze patterns of 47 VP (mean gestational age: 28weeks, mean birth weight: 948g, and mean chronological age: 49months) were assessed while viewing dynamic social scenes and compared with those of 25 typically developing (TD) and 25 children with ASD. The temporo-spatial gaze patterns were summarized on a two-dimensional plane using multidimensional scaling (MDS) and the median of the TD children was used to characterize the gazes of the VP children. Time spent viewing the face was also compared.

RESULTS

The VP children formed two clusters: one had a mean MDS distance comparable to that of TD group (n=32; VP-small), and the other had a larger mean distance comparable to that of ASD group (n=15; VP-large). The VP-large were similar to the ASD group by spending significantly less time viewing the face. Their performance was comparable to the TD during the initial 1s, but they could not remain focused on the face thereafter.

CONCLUSIONS

The VP children were objectively classified into two groups based on gaze behaviors. One group was comparable to TD children, whereas the other had difficulty maintaining attention and exhibited atypical viewing behaviors similar to those of the ASD group. Our method may be useful in identifying VP children at higher risk for experiencing social difficulties.

UNPACKING THE BURDEN OF CARE FOR INFANTS IN THE NICU

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

Meconium exposure and autism risk

OBJECTIVE

This study aims to determine whether fetal meconium passage is associated with autism.

STUDY DESIGN

This retrospective birth cohort analysis of 9 945 896 children born in California 1991 to 2008 linked discharge diagnosis and procedure codes for prenatal stressors, meconium-stained amniotic fluid (MSAF) and meconium aspiration syndrome (MAS) with autism diagnoses for 47 277 children through 2012. We assessed the relative risk of autism by meconium status using logistic regression, adjusting for demographic and clinical features.

RESULTS

Children exposed to meconium (MSAF and MAS) were more likely to be diagnosed with autism in comparison with unexposed children (0.60% and 0.52%, vs 0.47%, respectively). In adjusted analyses, there was a small increase in autism risk associated with MSAF exposure (adjusted relative risk (aRR) 1.18, 95% confidence interval (CI) 1.12 to 1.25), and a marginal association that failed to achieve significance between MAS and autism (aRR 1.08, 95% CI 0.98 to 1.20).

CONCLUSION

Resuscitation of neonates with respiratory compromise from in utero meconium exposure may mitigate long-term neurodevelopmental damage.

A possible role of the Infant/Toddler Sensory Profile in screening for autism: a proof-of-concept study in the specific sample of prematurely born children with birth weights <1,500 g

OBJECTIVE

The objective of this study was to explore the potential of the Infant/Toddler Sensory Profile (ITSP) as a screening tool for autism spectrum disorders (ASD) in prematurely born children.

METHODS

Parents of 157 children with birth weights <1,500 g (aged 2 years, corrected for prematurity; 88 boys, 69 girls) completed a screening battery that included the ITSP, Modified Checklist for Autism in Toddlers (M-CHAT), and the Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC). Children with known disabilities were excluded. All the children who were screened positive on any of the screening tools subsequently underwent clinical examination including the Autism Diagnostic Observation Schedule.

RESULTS

We used classification trees to answer the question whether ITSP (or some of its subscales) could be combined with the M-CHAT and/or the CSBS-DP-ITC or its subscales into an effective ASD screening tool. Using the CSBS-DP-ITC, overall score, and the Sensation Seeking subscale of the ITSP, we obtained a screening tool that was able to identify all of the ASD children in our sample (confirmed by cross-validation). The proposed screening tool is scored as follows: 1) if the overall CSBS-DP-ITC value is <45.5, then the screening is positive; 2) if the overall CSBS-DP-ITC value is ≥45.5 and the z-score of the Sensation Seeking subscale of ITSP is ≥1.54, then the screening is positive; 3) otherwise, the screening is negative.

CONCLUSION

The use of CSBS-DP-ITC in combination with the Sensation Seeking subscale of the ITSP improved the accuracy of autism screening in preterm children.

[Obstetrical APS: Is there a place for additional treatment to aspirin-heparin combination?]

Obstetrical APS is defined by thrombosis and/or obstetrical morbidity associated with persistent antiphospholipid antibodies. The aspirin and low molecular weighted heparin combination dramatically improved obstetrical outcome in APS patients. Several factors could be associated with obstetrical prognosis, as previous history of thrombosis, associated SLE, the presence of lupus anticoagulant and triple positivity of antiphospholipid antibodies. Obstetrical APS with isolated recurrent miscarriages is mostly associated with isolated anticardiolipids antibodies and have better obstetrical outcome. The pregnancy loss despite aspirin and heparin combination define the refractory obstetrical APS, and the prevalence could be estimated to 20-39%. Several other treatments have been used in small and open labeled studies, as steroids, intravenous immunoglobulins, plasma exchanges and hydroxychloroquine to improve the obstetrical outcome. Some other drugs as eculizumab and statins could also have physiopathological rational, but studies are necessary to define the place of these various drugs.

Early neurodevelopmental outcomes of extremely preterm infants

Infants born at extreme preterm gestation are at risk for both death and disability. Although rates of survival have improved for this population, and some evidence suggests a trend toward decreased neuromotor impairment over the past decades, a significant improvement in overall early neurodevelopmental outcome has not yet been realized. This review will examine the rates and types of neurodevelopmental impairment seen after extremely preterm birth, including neurosensory, motor, cognitive, and behavioral outcomes. We focus on early outcomes in the first 18-36 months of life, as the majority of large neonatal studies examining neurodevelopmental outcomes stop at this age. However, this early age is clearly just a first glimpse into lifetime outcomes; the neurodevelopmental effects of extreme prematurity may last through school age, adolescence, and beyond. Importantly, prematurity appears to be an independent risk factor for adverse development, but this population demonstrates considerable variability in the types and severity of impairments. Understanding both the nature and prevalence of neurodevelopmental impairment among extremely preterm infants is important because it can lead to targeted interventions that in turn may lead to improved outcomes.

Probability of an Autism Diagnosis by Gestational Age. NEWBORN AND INFANT NURSING REVIEWS : NAINR 2016;16:322-326. [PMID: 28989329 PMCID: PMC5627777 DOI: 10.1053/j.nainr.2016.09.019]

Early preterm infants (EPT) (<33 6/7 weeks) are at increased risk for autism spectrum disorders (ASDs) but prevalence estimates vary widely across studies. Furthermore, there are very few studies addressing the association between late preterm (LPT) births (34-36 6/7 weeks) and ASDs. To address the question of whether LPT infants carry the same risk for ASDs as full-term infants, this study aimed to estimate the relative probability of an ASD diagnosis using Bayes rule. A retrospective cohort analysis of 406 children was undertaken to look at gestational age, ASDs, and birth history. The application of Bayes rule was used, given that there is not sufficient information about the joint probabilities related to prematurity and autism. Using the estimated gestational age proportions within ASD diagnosis, plus national estimates of ASDs, probabilities for ASDs within a given gestational age were calculated. Among these 406 children with ASDs, 6.7% were EPT and 10.6% were LPT. In comparison to full term, EPT children are at 1.9 multiplicative increase in risk (95% CI [1.3, 2.5]). While the probability of ASDs for LPT children was higher than that for term, the estimated relative risk of the LPT infants was not statistically significant (95% CI [0.9, 1.5]). EPT infants were significantly more likely to be diagnosed with ASDs compared to their term peers. While the relative probability of ASD diagnosis among children born LPT was not statistically significant in this limited sample, the results indicate a possible elevated risk. A larger cohort is needed to adequately estimate this risk.

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.

Maternal infection during pregnancy and risk of autism spectrum disorders: A systematic review and meta-analysis

Conflicting evidence exists with regard to the relationship between maternal infection during pregnancy and the risk of autism spectrum disorder (ASD) in offspring. The aim of this meta-analysis was to systematically assess this relationship. To identify relevant studies, we conducted systematic searches in PubMed and Embase of scientific articles published through March 2016. Random-effects models were adopted to estimate overall relative risk. A total of 15 studies (2 cohort and 13 case-control studies) involving more than 40,000 ASD cases were included in our meta-analysis. Our results showed that maternal infection during pregnancy was associated with an increased risk of ASD in offspring (OR=1.13, 95% confidence interval (CI): 1.03-1.23), particularly among those requiring hospitalization (OR=1.30, 95% CI: 1.14-1.50). Subgroup analyses suggested that risk may be modulated by the type of infectious agent, time of infectious exposure, and site of infection. These findings indicate that maternal infection during pregnancy increases the risk of ASD in offspring. Possible mechanisms may include direct effects of pathogens and, more indirectly, the effects of inflammatory responses on the developing brain.

Early Postnatal Lipopolysaccharide Exposure Leads to Enhanced Neurogenesis and Impaired Communicative Functions in Rats

Perinatal infection is a well-identified risk factor for a number of neurodevelopmental disorders, including brain white matter injury (WMI) and Autism Spectrum Disorders (ASD). The underlying mechanisms by which early life inflammatory events cause aberrant neural, cytoarchitectural, and network organization, remain elusive. This study is aimed to investigate how systemic lipopolysaccharide (LPS)-induced neuroinflammation affects microglia phenotypes and early neural developmental events in rats. We show here that LPS exposure at early postnatal day 3 leads to a robust microglia activation which is characterized with mixed microglial proinflammatory (M1) and anti-inflammatory (M2) phenotypes. More specifically, we found that microglial M1 markers iNOS and MHC-II were induced at relatively low levels in a regionally restricted manner, whereas M2 markers CD206 and TGFβ were strongly upregulated in a sub-set of activated microglia in multiple white and gray matter structures. This unique microglial response was associated with a marked decrease in naturally occurring apoptosis, but an increase in cell proliferation in the subventricular zone (SVZ) and the dentate gyrus (DG) of hippocampus. LPS exposure also leads to a significant increase in oligodendrocyte lineage population without causing discernible hypermyelination. Moreover, LPS-exposed rats exhibited significant impairments in communicative and cognitive functions. These findings suggest a possible role of M2-like microglial activation in abnormal neural development that may underlie ASD-like behavioral impairments.

Extremely Preterm Born Children at Very High Risk for Developing Autism Spectrum Disorder

This study aimed to provide a more comprehensive picture of the prevalence of autism spectrum disorder (ASD) in a geographic cohort of extremely preterm born adolescents by using established diagnostic instruments in addition to screening instruments. 53 participants passed a screening procedure with two screening instruments and a diagnostic evaluation with a semi-structured assessment and a parent interview. 28 % of the adolescents had a community based clinical diagnosis of ASD. When research diagnoses were also taken into account, this rate increased to 40 %. Intellectual disability, language impairment and behavioural difficulties are characteristic for these children with ASD. This study is to our knowledge the first to use ASD-specific diagnostic instruments to confirm ASD diagnoses in extremely preterm born children in early adolescence. The study expands findings of previous research and raises the need for follow-up into late childhood and early adolescence.

Altered resting-state functional connectivity in emotion-processing brain regions in adults who were born very preterm

BACKGROUND

Very preterm birth (VPT; <32 weeks of gestation) has been associated with impairments in emotion regulation, social competence and communicative skills. However, the neuroanatomical mechanisms underlying such impairments have not been systematically studied. Here we investigated the functional integrity of the amygdala connectivity network in relation to the ability to recognize emotions from facial expressions in VPT adults.

METHOD

Thirty-six VPT-born adults and 38 age-matched controls were scanned at rest in a 3-T MRI scanner. Resting-state functional connectivity (rs-fc) was assessed with SPM8. A seed-based analysis focusing on three amygdalar subregions (centro-medial/latero-basal/superficial) was performed. Participants' ability to recognize emotions was assessed using dynamic stimuli of human faces expressing six emotions at different intensities with the Emotion Recognition Task (ERT).

RESULTS

VPT individuals compared to controls showed reduced rs-fc between the superficial subregion of the left amygdala, and the right posterior cingulate cortex (p = 0.017) and the left precuneus (p = 0.002). The VPT group further showed elevated rs-fc between the left superficial amygdala and the superior temporal sulcus (p = 0.008). Performance on the ERT showed that the VPT group was less able than controls to recognize anger at low levels of intensity. Anger scores were significantly associated with rs-fc between the superficial amygdala and the posterior cingulate cortex in controls but not in VPT individuals.

CONCLUSIONS

These findings suggest that alterations in rs-fc between the amygdala, parietal and temporal cortices could represent the mechanism linking VPT birth and deficits in emotion processing.

Interpretation of ambiguities by schoolchildren with low birth weight from Embu das Artes, São Paulo state, Brazil

PURPOSE

To assess the development of language regarding the ability to recognize and interpret lexical ambiguity in low-birth-weight schoolchildren enrolled at the school system in the municipality of Embu das Artes, Sao Paulo state, compared with that of schoolchildren with normal birth weight.

METHODS

A case-control, retrospective, cross-sectional study conducted with 378 schoolchildren, both genders, aged 5 to 9.9 years, from the municipal schools of Embu das Artes. Study Group (SG) comprising 210 schoolchildren with birth weight < 2500 g. Control Group (CG) composed of 168 school children with birth weight ≥ 2500 g. Participants of both groups were compared with respect to the skills of recognition and verbal interpretation of sentences containing lexical ambiguity using the Test of Language Competence. Variables of interest: Age and gender of children; age and schooling of mothers. Statistical analysis: Descriptive analysis to characterize the sample and score per group; Student's t test for comparison between the total scores of each skill/subtest; Chi-square test to compare items within each subtest; multiple regression analysis for the intervening variables.

RESULTS

Participants of the SG presented lower scores for ambiguous sentences compared with those of participants of the CG. Multiple regression analysis showed that child's current age was a predictor for all metalinguistic skills regarding interpretation of ambiguities in both groups.

CONCLUSION

Participants of the SG presented lower specific and total scores than those of participants of the CG for ambiguity skills. The child's current age factor positively influenced the ambiguity skills in both groups.

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

BACKGROUND

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

PURPOSE

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

IMPLICATIONS FOR PRACTICE AND RESEARCH

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

Maternal Infection During Pregnancy and Autism Spectrum Disorders

We conducted a nested case-control study including 407 cases and 2,075 frequency matched controls to investigate the association between maternal infections during pregnancy and risk of autism spectrum disorders (ASD). Cases, controls, and maternal infections were ascertained from Kaiser Permanente Northern California clinical databases. No overall association between diagnoses of any maternal infection during pregnancy and ASD was observed [adjusted odds ratio (ORadj) = 1.15, 95 % confidence interval (CI) 0.92-1.43]. However, women with infections diagnosed during a hospital admission (ORadj = 1.48, 95 % CI 1.07-2.04), particularly bacterial infections (ORadj = 1.58, 95 % CI 1.06-2.37), were at increased risk of delivering a child with ASD. Multiple infections during pregnancy were associated with ASD (ORadj = 1.36, 95 % CI 1.05-1.78).

Stability of early risk assessment for autism spectrum disorder in preterm infants

Stability and change in early autism spectrum disorder risk were examined in a cohort of 99 preterm infants (⩽34 weeks of gestation) using the Autism Observation Scale for Infants at 8 and 12 months and the Autism Diagnostic Observation Schedule—Toddler Module at 18 months. A total of 21 infants were identified at risk by the Autism Observation Scale for Infants at 8 months, and 9 were identified at risk at 12 months, including 4 children who were not previously identified. At 18 months, eight children were identified at risk for autism spectrum disorder using the Autism Diagnostic Observation Schedule—Toddler Module, only half of whom had been identified using the original Autism Observation Scale for Infants cutoffs. Results are discussed in relation to early trajectories of autism spectrum disorder risk among preterm infants as well as identifying social-communication deficiencies associated with the early preterm behavioral phenotype.

Metabolomics of autism spectrum disorders: early insights regarding mammalian-microbial cometabolites

INTRODUCTION

Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders consisting of delayed or impaired language development and difficulties in social interactions. The very high degree of phenotypic heterogeneity in ASD originates from the interaction between environmental risk factors and susceptible genetic loci, leading to epigenetic DNA methylation. Advances in system biology are becoming strategic for implementing knowledge on the ASD aetiology and for the early diagnosis of the disease after birth.

AREAS COVERED

We overhauled the value of either targeted or untargeted metabolomics studies in autism for identifying the most relevant metabolic pathways and key metabolites implicated in the disease, with special emphasis to mammalian-microbial metabolites. The most discriminant metabolites in ASD belong to amino acid metabolism, antioxidant status, nicotinic acid metabolism, and mitochondrial metabolism. Expert commentary: Most published studies point out the role of metabolites derived from the gut microbiota: they can modulate the behavioral phenotype of the autistic children, greatly influencing host metabolic pathways and the immune system, shaping the individual susceptibility to the disease. Pitfalls and caveats in metabolomics results across studies have been additionally recognized and discussed leading to the conclusion that metabolomics studies in ASD are far to be definitive and univocal.

Prevalence and associated features of autism spectrum disorder in extremely low gestational age newborns at age 10 years

We sought to estimate the prevalence of autism spectrum disorder (ASD) in children born extremely preterm relative to the U.S. population risk of 1.5% [CDC, 2014] using the best-available diagnostic procedures and minimizing confounding with other neurodevelopmental impairments. Eight hundred and eighty nine of 966 (92%) 10-year-old children from the Extremely Low Gestational Age Newborn birth cohort, delivered at 23-27 weeks gestation in 2002-2004, participated. Children meeting ASD screening criteria on the Social Communication Questionnaire were evaluated with the Autism Diagnostic Interview-Revised (ADI-R). Those meeting ADI-R criteria were assessed with the Autism Diagnostic Observation Schedule-2 (ADOS-2). A positive ADOS-2 score was the criterion for ASD. Twenty-six participants were not assessed for ASD because of severe sensory or motor impairment. In the remaining sample, 61 children met criteria for ASD, resulting in a prevalence of 7.1% (95% CI = 5.5-9.0). ASD risk decreased with increasing gestational age, from 15.0% (95% CI = 10.0-21.2) for 23-24 weeks, 6.5% (95% CI = 4.2-9.4) for 25-26 weeks, to 3.4% (95% CI = 1.6-6.1) for 27 weeks gestational age, and this association was independent of IQ. Among children with ASD, 40% had intellectual disability. The male-to-female ratio of children with ASD was 2.1:1 (95% CI = 1.2:1-3.5:1), lower than in the general population (4:1). ASD prevalence in the ELGAN cohort was four times higher than in the general population, and was strongly associated with gestational age, underscoring the need for enhanced ASD screening of children born preterm, and suggesting that some risk factors associated with preterm birth may also play a role in the etiology of autism. Autism Res 2017, 10: 224-232. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Advances in family-based interventions in the neonatal ICU

PURPOSE OF REVIEW

Despite advances in medical care, preterm infants remain at risk for many adverse outcomes. This article reviews findings from several recent neonatal ICU (NICU) interventions and a trial of a novel nurture-based approach, Family Nurture Intervention (FNI).

RECENT FINDINGS

Recent trials reviewed here find positive effects of a variety of family-related interventions focused on parental guidance. These interventions target prescribed physical activities with infants, parents' stress, and the parents' ability to recognize their positive and negative behaviors with their infants. Beneficial effects include reductions in parenting stress, maternal anxiety, and depression. A different approach, FNI, is aimed at establishing mother-infant emotional connection. As in other trials, FNI also decreased maternal symptoms of anxiety and depression, and increased maternal sensitivity. Additionally, FNI led to positive short and long-term effects on infant neurobehavioral outcomes at term and 18 months.

SUMMARY

A number of recent parent-based NICU interventions have been effective at reducing preterm parent stress. Another, FNI, has positive effects on both maternal and infant outcomes and promises to be cost-effective. Future decreases in long-term morbidity in preterm infants will increasingly rely on nonmedical interventions. Therefore, the rigorous development and testing of such interventions should be a high priority in perinatology research.

Persistence of Cerebral Palsy Diagnosis: Assessment of a Low-Birth-Weight Cohort at Ages 2, 6, and 9 Years

We examined the stability of nondisabling and disabling cerebral palsy at age 2 in a longitudinally followed tri-county low-birth-weight (<2000 g) birth cohort. A total of 1105 newborns were enrolled, 901 (81.5%) survived to age 2, and 86% (n = 777) were followed up. Of the 113 cerebral palsy diagnoses at age 2, 61 (9% of the cohort, n = 61/777) had disabling cerebral palsy and 52 (7%, n = 52/777) had nondisabling cerebral palsy. Of 48 followed children diagnosed with disabling cerebral palsy at age 2, 98% were again classified as having cerebral palsy at school age, and 1 had an uncertain cerebral palsy status. By contrast, 41% (n = 17) of the 43 children diagnosed with nondisabling cerebral palsy at age 2 were classified as not having cerebral palsy. Of the 517 followed children who were not diagnosed with cerebral palsy at age 2, 7% (n = 35) were classified as having late emerging nondisabling cerebral palsy at school age.

Autism in Toddlers Born Very Preterm

OBJECTIVE

This study aimed to determine the prevalence of autism spectrum disorder (ASD) by using the Autism Diagnostic Observation Schedule-Generic (ADOS-G) classifications in children born very preterm during their toddler years.

METHODS

Two birth cohorts of toddlers (2 and 4 years old) each recruited over 12 months and born at <29 weeks' gestation were administered the Modified Checklist of Autism in Toddlers-Follow-up Interview (M-CHAT-FI) screen, the ADOS-G, and developmental assessments. The ADOS-G was conducted on toddlers with M-CHAT-FI-positive screens.

RESULTS

Data were available on 88% (169/192) of children. In total, 22 (13%) toddlers screened positive and 3 (1.8%) were confirmed diagnostically with ASD. These 3 cases reached the highest ADOS-G threshold classification of autism. All but 1 child who scored below the ADOS-G thresholds (11/12) demonstrated some difficulty with social communication. Risk was significantly increased for co-occurring neurodevelopmental problems in 21 of the 22 positive-screen ASD cases. Adaptive behavior (P < .001) was the only co-occurring factor independently predictive of ASD in toddlers.

CONCLUSIONS

Children born very preterm are at increased risk of ASD. By using the ADOS-G, we found a lower incidence of ASD in children born at <29 weeks' gestation compared with previous studies. Children who screened positive for ASD on the M-CHAT-FI had developmental delays consistent with subthreshold communication impairment.

Longitudinal study of very low birth weight infants until 9years of age; attention deficit hyperactivity and autistic features are correlated with their cognitive functions

BACKGROUND

Increasing attention has been given to neuro-developmental problems of very low birth weight infants (VLBWIs) at school age. However, it remains unknown whether their neuro-cognitive function and psychiatric symptoms are mutually associated.

AIM

The aim of this study was to investigate the characteristics of neuro-cognitive functions in VLBWIs and their relationship with psychiatric symptoms.

METHODS

A total of 160 VLBWIs who were born at our institute between 2001 and 2005 were recruited consecutively and followed up until nine years of age. The developmental profiles were obtained from 77 children (45 males and 32 females) at six to nine years of age using the ADHD Rating Scale-Fourth edition (ADHD-RS), Autism Screening Questionnaire-Japanese version (ASQ-J) and the Wechsler Intelligence Scale for Children-Third edition (WISC-III).

RESULTS

The full-scale intelligence quotient did not significantly differ between the male and female VLBWIs (median: 91 vs. 99, p=0.17). The males had higher total scores (median: 13 vs. 4, p<0.01) and higher scores on the subscales of Inattention (8 vs. 2, p<0.01) and Hyperactivity-Impulsivity (5 vs. 1, p<0.01) of the ADHD-RS compared with the females. The Verbal Comprehension Index (VCI) of the WISC-III was inversely correlated with the total scores of the ASQ-J for all VLBWIs (n=77, rc: -0.32, 95% CI: -0.19 to -0.01, p=0.04). We also observed that the Freedom from Distractibility Index (FDI) of the WISC-III was significantly correlated with the Inattentive scores of the ADHD-RS (n=45, rc: -0.18, 95% CI: -0.35 to -0.02, p=0.03) in male, but not female VLBWIs.

CONCLUSIONS

We herein report that the VCI and FDI of the WISC-III were correlated with the autism spectrum disorder and attention deficit hyperactivity disorder symptoms, respectively, in male VLBWIs.

Maternal high-fat diet programming of the neuroendocrine system and behavior

This article is part of a Special Issue "SBN 2014". Maternal obesity, metabolic state, and diet during gestation have profound effects on offspring development. The prevalence of neurodevelopmental and mental health disorders has risen rapidly in the last several decades in parallel with the rise in obesity rates. Evidence from epidemiological studies indicates that maternal obesity and metabolic complications increase the risk of offspring developing behavioral disorders such as attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASD), and schizophrenia. Animal models show that a maternal diet high in fat similarly disrupts behavioral programming of offspring, with animals showing social impairments, increased anxiety and depressive behaviors, reduced cognitive development, and hyperactivity. Maternal obesity, metabolic conditions, and high fat diet consumption increase maternal leptin, insulin, glucose, triglycerides, and inflammatory cytokines. This leads to increased risk of placental dysfunction, and altered fetal neuroendocrine development. Changes in brain development that likely contribute to the increased risk of behavioral and mental health disorders include increased inflammation in the brain, as well as alterations in the serotonergic system, dopaminergic system and hypothalamic-pituitary-adrenal (HPA) axis.

Family Nurture Intervention in the Neonatal Intensive Care Unit improves social-relatedness, attention, and neurodevelopment of preterm infants at 18 months in a randomized controlled trial

BACKGROUND

Preterm infants are at high risk for adverse neurodevelopmental and behavioral outcomes. Family Nurture Intervention (FNI) in the Neonatal Intensive Care Unit (NICU) is designed to counteract adverse effects of separation of mothers and their preterm infants. Here, we evaluate effects of FNI on neurobehavioral outcomes.

METHODS

Data were collected at 18 months corrected age from preterm infants. Infants were assigned at birth to FNI or standard care (SC). Bayley Scales of Infant Development III (Bayley-III) were assessed for 76 infants (SC, n = 31; FNI, n = 45); the Child Behavior Checklist (CBCL) for 57 infants (SC, n = 31; FNI, n = 26); and the Modified Checklist for Autism in Toddlers (M-CHAT) was obtained for 59 infants (SC, n = 33; FNI, n = 26).

RESULTS

Family Nurture Intervention significantly improved Bayley-III cognitive (p = .039) and language (p = .008) scores for infants whose scores were greater than 85. FNI infants had fewer attention problems on the CBCL (p < .02). FNI improved total M-CHAT scores (p < .02). Seventy-six percent of SC infants failed at least one of the M-CHAT items, compared to 27% of FNI infants (p < .001). In addition, 36% of SC infants versus 0% of FNI infants failed at least one social-relatedness M-CHAT item (p < .001).

CONCLUSIONS

Family Nurture Intervention is the first NICU intervention to show significant improvements in preterm infants across multiple domains of neurodevelopment, social-relatedness, and attention problems. These gains suggest that an intervention that facilitates emotional interactions between mothers and infants in the NICU may be key to altering developmental trajectories of preterm infants.

High angular resolution diffusion imaging in a child with autism spectrum disorder and comparison with his unaffected identical twin

In recent years, the use of brain diffusion MRI has led to the hypothesis that children with autism spectrum disorder (ASD) show abnormally connected brains. We used the model of disease-discordant identical twins to test the hypothesis that higher-order diffusion MRI protocols are able to detect abnormal connectivity in a single subject. We studied the structural connectivity of the brain of a child with ASD, and of that of his unaffected identical twin, using high angular resolution diffusion imaging (HARDI) probabilistic tractography. Cortical regions were automatically parcellated from high-resolution structural images, and HARDI-based connection matrices were produced for statistical comparison. Differences in diffusion indexes between subjects were tested by Wilcoxon signed rank test. Tracts were defined as discordant when they showed a between-subject difference of 10 percent or more. Around 11 percent of the discordant intra-hemispheric tracts showed lower fractional anisotropy (FA) values in the ASD twin, while only 1 percent showed higher values. This difference was significant. Our findings in a disease-discordant identical twin pair confirm previous literature consistently reporting lower FA values in children with ASD.

Family Nurture Intervention in preterm infants alters frontal cortical functional connectivity assessed by EEG coherence

AIM

To assess the impact of Family Nurture Intervention (FNI) on cortical function in preterm infants at term age.

METHODS

Family Nurture Intervention is a NICU-based intervention designed to establish emotional connection between mothers and preterm infants. Infants born at 26-34 weeks postmenstrual age (PMA) were divided into two groups, standard care (SC, N = 49) and FNI (FNI, N = 56). Infants had EEG recordings of ~one hour duration with 124 lead nets between 37 and 44 weeks PMA. Coherence was measured between all pairs of electrodes in ten frequency bands. Data were summarised both within and between 12 regions during two sleep states (active, quiet).

RESULTS

Coherence levels were negatively correlated with PMA age in both groups. As compared to SC infants, FNI infants showed significantly lower levels of EEG coherence (1-18 Hz) largely within and between frontal regions.

CONCLUSION

Coherence in FNI infants was decreased in regions where we previously found robust increases in EEG power. As coherence decreases with age, results suggest that FNI may accelerate brain maturation particularly in frontal brain regions, which have been shown in research by others to be involved in regulation of attention, cognition and emotion regulation; domains deficient in preterm infants.

Preeclampsia, placental insufficiency, and autism spectrum disorder or developmental delay

IMPORTANCE

Increasing evidence suggests that autism spectrum disorder (ASD) and many forms of developmental delay (DD) originate during fetal development. Preeclampsia may trigger aberrant neurodevelopment through placental, maternal, and fetal physiologic mechanisms.

OBJECTIVE

To determine whether preeclampsia is associated with ASD and/or DD.

DESIGN, SETTING, AND PARTICIPANTS

The Childhood Autism Risks from Genetics and the Environment (CHARGE) study is a population-based, case-control investigation of ASD and/or DD origins. Children from 20 California counties aged 24 to 60 months at the time of recruitment and living in catchment areas with a biological parent fluent in English or Spanish were enrolled from January 29, 2003, through April 7, 2011. Children with ASD (n = 517) and DD (n = 194) were recruited through the California Department of Developmental Services, the Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, and referrals. Controls with typical development (TD) (n = 350) were randomly selected from birth records and frequency matched on age, sex, and broad geographic region. Physicians diagnosing preeclampsia were masked to neurodevelopmental outcome, and those assessing neurodevelopmental function were masked to preeclampsia status.

EXPOSURES

Preeclampsia and placental insufficiency were self-reported and abstracted from medical records.

MAIN OUTCOMES AND MEASURES

The Autism Diagnostic Observation Schedule and Autism Diagnostic Interview-Revised were used to confirm ASD, whereas children with DD and TD were confirmed by Mullen Scales of Early Learning and Vineland Adaptive Behavior Scales and were free of autistic symptoms. Hypotheses were formulated before data collection.

RESULTS

Children with ASD were twice as likely to have been exposed in utero to preeclampsia as controls with TD after adjustment for maternal educational level, parity, and prepregnancy obesity (adjusted odds ratio, 2.36; 95% CI, 1.18-4.68); risk increased with greater preeclampsia severity (test for trend, P = .02). Placental insufficiency appeared responsible for the increase in DD risk associated with severe preeclampsia (adjusted odds ratio, 5.49; 95% CI, 2.06-14.64).

CONCLUSIONS AND RELEVANCE

Preeclampsia, particularly severe disease, is associated with ASD and DD. Faulty placentation manifests in the mother as preeclampsia with vascular damage, enhanced systemic inflammation, and insulin resistance; in the placenta as oxygen and nutrient transfer restriction and oxidative stress; and in the fetus as growth restriction and progressive hypoxemia. All are potential mechanisms for neurodevelopmental compromise.

Infants born late/moderately preterm are at increased risk for a positive autism screen at 2 years of age

OBJECTIVES

To assess the prevalence of positive screens using the Modified Checklist for Autism in Toddlers (M-CHAT) questionnaire and follow-up interview in late and moderately preterm (LMPT; 32-36 weeks) infants and term-born controls.

STUDY DESIGN

Population-based prospective cohort study of 1130 LMPT and 1255 term-born infants. Parents completed the M-CHAT questionnaire at 2-years corrected age. Parents of infants with positive questionnaire screens were followed up with a telephone interview to clarify failed items. The M-CHAT questionnaire was re-scored, and infants were classified as true or false positives. Neurosensory, cognitive, and behavioral outcomes were assessed using parent report.

RESULTS

Parents of 634 (57%) LMPT and 761 (62%) term-born infants completed the M-CHAT questionnaire. LMPT infants had significantly higher risk of a positive questionnaire screen compared with controls (14.5% vs 9.2%; relative risk [RR] 1.58; 95% CI 1.18, 2.11). After follow-up, significantly more LMPT infants than controls had a true positive screen (2.4% vs 0.5%; RR 4.52; 1.51, 13.56). This remained significant after excluding infants with neurosensory impairments (2.0% vs 0.5%; RR 3.67; 1.19, 11.3).

CONCLUSIONS

LMPT infants are at significantly increased risk for positive autistic screen. An M-CHAT follow-up interview is essential as screening for autism spectrum disorders is especially confounded in preterm populations. Infants with false positive screens are at risk for cognitive and behavioral problems.

Prenatal glucocorticoid exposure in rats: programming effects on stress reactivity and cognition in adult offspring

Human epidemiological studies have provided compelling evidence that prenatal exposure to stress is associated with significantly increased risks of developing psychiatric disorders in adulthood. Exposure to excessive maternal glucocorticoids may underlie this fetal programming effect. In the current study, we assessed how prenatal dexamethasone administration during the last week of gestation affects stress reactivity and cognition in adult offspring. Stress reactivity was assessed by evaluating anxiety-like behavior on an elevated plus maze and in an open field. In addition, to characterize the long-term cognitive outcomes of prenatal exposure to glucocorticoids, animals were assessed on two cognitive tasks, a spatial reference memory task with reversal learning and a delayed matching to position (DMTP) task. Our results suggest that prenatal exposure to dexamethasone had no observable effect on anxiety-like behavior, but affected cognition in the adult offspring. Prenatally dexamethasone-exposed animals showed a transient deficit in the spatial reference memory task and a trend to faster acquisition during the reversal-learning phase. Furthermore, prenatally dexamethasone-treated animals also showed faster learning of new platform positions in the DMTP task. These results suggest that fetal overexposure to glucocorticoids programs a phenotype characterized by cognitive flexibility and adaptability to frequent changes in environmental circumstances. This can be viewed as an attempt to increase the fitness of survival in a potentially hazardous postnatal environment, as predicted by intrauterine adversity. Collectively, our data suggest that prenatal exposure to dexamethasone in rats could be used as an animal model for studying some cognitive components of related psychiatric disorders.

Social perception in children born at very low birthweight and its relationship with social/behavioral outcomes

BACKGROUND

Research has shown that children born very prematurely are at substantially elevated risk for social and behavioral difficulties similar to those seen in full-term children with autism spectrum disorders (ASDs).

METHODS

To gain insight into core deficits that may underlie these difficulties, in this study, we assessed the social perceptual skills of 8- to 11-year-old children born at very low birthweight (VLBW) (<1,500 g) and age-matched, full-term controls, using the Child and Adolescent Social Perception Measure. We also assessed social and behavioral outcomes with two parent-report measures used in ASD screening.

RESULTS

Children in the preterm group had normal range estimated verbal IQ. However, we found that they were impaired in their ability to use nonverbal cues from moving faces and bodies, and situational cues, to correctly identify the emotions of characters depicted in videotaped social interactions. Their performance on this task was related to the number of 'autistic-like' traits they displayed.

CONCLUSIONS

This research highlights links between social perceptual deficits and poor social and behavioral outcomes in children born very prematurely. The results also suggest that even those who have escaped major intellectual/language problems are at risk for social and behavioral problems that can be of clinical concern.

Obstetrical APS: is there a place for hydroxychloroquine to improve the pregnancy outcome?

The use of the conventional APS treatment (the combination of low-dose aspirin and LMWH) dramatically improved the obstetrical prognosis in primary obstetrical APS (OAPS). The persistence of adverse pregnancy outcome raises the need to find other drugs to improve obstetrical outcome. Hydroxychloroquine is widely used in patients with various autoimmune diseases, particularly SLE. Antimalarials have many anti-inflammatory, anti-aggregant and immune-regulatory properties: they inhibit phospholipase activity, stabilize lysosomal membranes, block the production of several pro-inflammatory cytokines and, in addition, impair complement-dependent antigen-antibody reactions. There is ample evidence of protective effects of hydroxychloroquine in OAPS similar to the situation in SLE arising from in vitro studies of pathophysiological working mechanism of hydroxychloroquine. However, the clinical data on the use of hydroxychloroquine in primary APS are lacking and prospective studies are necessary.

Local and global aspects of biological motion perception in children born at very low birth weight

Biological motion perception can be assessed using a variety of tasks. In the present study, 8- to 11-year-old children born prematurely at very low birth weight (<1500 g) and matched, full-term controls completed tasks that required the extraction of local motion cues, the ability to perceptually group these cues to extract information about body structure, and the ability to carry out higher order processes required for action recognition and person identification. Preterm children exhibited difficulties in all 4 aspects of biological motion perception. However, intercorrelations between test scores were weak in both full-term and preterm children--a finding that supports the view that these processes are relatively independent. Preterm children also displayed more autistic-like traits than full-term peers. In preterm (but not full-term) children, these traits were negatively correlated with performance in the task requiring structure-from-motion processing, r(30) = -.36, p < .05), but positively correlated with the ability to extract identity, r(30) = .45, p < .05). These findings extend previous reports of vulnerability in systems involved in processing dynamic cues in preterm children and suggest that a core deficit in social perception/cognition may contribute to the development of the social and behavioral difficulties even in members of this population who are functioning within the normal range intellectually. The results could inform the development of screening, diagnostic, and intervention tools.

Pregnancy health problems and low birth weight associated with maternal insecure attachment style

We aimed to determine the association between attachment style and health problems during pregnancy, as well as perinatal health variables. In 122 mothers who were 2–18 months postpartum, hot flushes, vaginal discharge, back pain, breast tenderness, hair changes, and psychological problems were shown to be associated with insecure attachment as measured by the Adult Attachment Style Questionnaires. Babies born to mothers with insecure attachment were more likely to have a low birth weight. It is vital to increase awareness of insecure attachment style as a risk factor among perinatal health care providers to optimize services.

Prenatal and perinatal risk factors in a twin study of autism spectrum disorders

INTRODUCTION

Multiple studies associate prenatal and perinatal complications with increased risks for autism spectrum disorders (ASDs). The objectives of this study were to utilize a twin study design to 1) Investigate whether shared gestational and perinatal factors increase concordance for ASDs in twins, 2) Determine whether individual neonatal factors are associated with the presence of ASDs in twins, and 3) Explore whether associated factors may influence males and females differently.

METHODS

Data from medical records and parent response questionnaires from 194 twin pairs, in which at least one twin had an ASD, were analyzed.

RESULTS

Shared factors including parental age, prenatal use of medications, uterine bleeding, and prematurity did not increase concordance risks for ASDs in twins. Among the individual factors, respiratory distress demonstrated the strongest association with increased risk for ASDs in the group as a whole (OR 2.11, 95% CI 1.27-3.51). Furthermore, respiratory distress (OR 2.29, 95% CI 1.12-4.67) and other markers of hypoxia (OR 1.99, 95% CI 1.04-3.80) were associated with increased risks for ASDs in males, while jaundice was associated with an increased risk for ASDs in females (OR 2.94, 95% CI 1.28-6.74).

CONCLUSIONS

Perinatal factors associated with respiratory distress and other markers of hypoxia appear to increase risk for autism in a subgroup of twins. Future studies examining potential gender differences and additional prenatal, perinatal and postnatal environmental factors are required for elucidating the etiology of ASDs and suggesting new methods for treatment and prevention.

Social attribution skills of children born preterm at very low birth weight

Children born prematurely at very low birth weight (<1500 g) are at increased risk for impairments affecting social functioning, including autism spectrum disorders (e.g., Johnson et al., 2010). In the current study, we used the Happé-Frith animated triangles task (Abell, Happé, & Frith, 2000) to study social attribution skills in this population. In this task, typical viewers attribute intentionality and mental states to shapes, based on characteristics of their movements. Participants included 34 preterm children and 36 full-term controls, aged 8-11 years. Groups were comparable in terms of age at test, gender, handedness, and socioeconomic status; they also performed similarly on tests of selective attention/processing speed and verbal intelligence. Relative to full-term peers, preterm children's descriptions of the animations were less appropriate overall; they also overattributed intentionality/mental states to randomly moving shapes and underattributed intentionality/mental states to shapes that seemed to be interacting socially. Impairments in the ability to infer the putative mental states of triangles from movement cues alone were most evident in children displaying more "autistic-like" traits, and this may reflect atypical development of and/or functioning in, or atypical connections between, parts of the social brain.

Obstetric antiphospholipid syndrome: a recent classification for an old defined disorder

Obstetric antiphospholipid syndrome (APS) is now being recognized as a distinct entity from vascular APS. Pregnancy morbidity includes >3 consecutive and spontaneous early miscarriages before 10weeks of gestation; at least one unexplained fetal death after the 10th week of gestation of a morphologically normal fetus; a premature birth before the 34th week of gestation of a normal neonate due to eclampsia or severe pre-eclampsia or placental insufficiency. It is not well understood how antiphospholipid antibodies (aPLs), beyond their diagnostic and prognostic role, contribute to pregnancy manifestations. Indeed aPL-mediated thrombotic events cannot explain the obstetric manifestations and additional pathogenic mechanisms, such as a placental aPL mediated complement activation and a direct effect of aPLs on placental development, have been reported. Still debated is the possible association between aPLs and infertility and the effect of maternal autoantibodies on non-vascular manifestations in the babies. Combination of low dose aspirin and unfractionated or low molecular weight heparin is the effective treatment in most of the cases. However, pregnancy complications, in spite of this therapy, can occur in up to 20% of the patients. Novel alternative therapies able to abrogate the aPL pathogenic action either by interfering with aPL binding at the placental level or by inhibiting the aPL-mediated detrimental effect are under active investigation.

In vivo detection of reduced Purkinje cell fibers with diffusion MRI tractography in children with autistic spectrum disorders

Postmortem neuropathology studies report reduced number and size of Purkinje cells (PC) in a majority of cerebellar specimens from persons diagnosed with autism spectrum disorders (ASD). We used diffusion weighted MRI tractography to investigate whether structural changes associated with reduced number and size of PC, could be detected in vivo by measuring streamlines connecting the posterior-lateral region of the cerebellar cortex to the dentate nucleus using an independent component analysis with a ball and stick model. Seed regions were identified in the cerebellar cortex, and streamlines were identified to two sorting regions, the dorsal dentate nucleus (DDN) and the ventral dentate nucleus (VDN), and probability of connection and measures of directional coherence for these streamlines were calculated. Tractography was performed in 14 typically developing children (TD) and 15 children with diagnoses of ASD. Decreased numbers of streamlines were found in the children with ASD in the pathway connecting cerebellar cortex to the right VDN (p-value = 0.015). Reduced fractional anisotropy (FA) values were observed in pathways connecting the cerebellar cortex to the right DDN (p-value = 0.008), the right VDN (p-value = 0.010) and left VDN (p-value = 0.020) in children with ASD compared to the TD group. In an analysis of single subjects, reduced FA in the pathway connecting cerebellar cortex to the right VDN was found in 73% of the children in the ASD group using a threshold of 3 standard errors of the TD group. The detection of diffusion changes in cerebellum may provide an in vivo biomarker of Purkinje cell pathology in children with ASD.

Prevalence and neonatal factors associated with autism spectrum disorders in preterm infants

OBJECTIVES

To determine the prevalence of autism spectrum disorders (ASD) across gestational age, examine the risk of ASD by gestational age controlling for other risk factors, and identify potential risk factors in the neonatal intensive care unit.

STUDY DESIGN

A retrospective cohort of infants born at ≥ 24 weeks between January 1, 2000, and December 31, 2007 at 11 Kaiser Permanente Northern California hospitals (n = 195,021). ASD cases were defined by a diagnosis made at a Kaiser Permanente ASD evaluation center, by a clinical specialist, or by a pediatrician. Cox proportional hazards regression models were used to evaluate the association between gestational age and ASD as well as potential risk factors in the neonatal intensive care unit and ASD.

RESULTS

The prevalence of ASD in infants <37 weeks was 1.78% compared with 1.22% in infants born ≥ 37 weeks (P < .001). Compared with term infants, infants born at 24-26 weeks had an adjusted hazard ratio (HR) for a diagnosis of ASD of 2.7 (95% CI 1.5-5.0). Infants born at 27-33 weeks (adjusted HR 1.4, 95% CI 1.1-1.8) and 34-36 weeks (adjusted HR 1.3, 95% CI 1.1-1.4) were also at increased risk. High frequency ventilation and intracranial hemorrhage were associated with ASD in infants < 34 weeks.

CONCLUSIONS

ASD was ~ 3 times more prevalent in infants <27 weeks compared with term infants. Each week of shorter gestation was associated with an increased risk of ASD. High frequency ventilation and intracranial hemorrhage were associated with ASD among infants <34 weeks.

Evaluation of early childhood social-communication difficulties in children born preterm using the Quantitative Checklist for Autism in Toddlers

OBJECTIVES

To characterize early childhood social-communication skills and autistic traits in children born very preterm using the Quantitative Checklist for Autism in Toddlers (Q-CHAT) and explore neonatal and sociodemographic factors associated with Q-CHAT scores.

STUDY DESIGN

Parents of children born before 30 weeks gestation and enrolled in a study evaluating routinely collected neurodevelopmental data between the post-menstrual ages of 20 and 28 months were invited to complete the Q-CHAT questionnaire. Children with severe neurosensory disabilities and cerebral palsy were excluded. Participants received neurodevelopmental assessments using the Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III). Q-CHAT scores of this preterm cohort were compared with published general population scores. The association between Bayley-III cognitive and language scores and neonatal and sociodemographic factors with Q-CHAT scores were examined.

RESULTS

Q-CHAT questionnaires were completed from 141 participants. At a mean post-menstrual age of 24 months, the Q-CHAT scores of the preterm cohort (mean 33.7, SD 8.3) were significantly higher than published general population scores (mean 26.7; SD 7.8), indicating greater social-communication difficulty and autistic behavior. Preterm children received higher scores, particularly in the categories of restricted, repetitive, stereotyped behavior, communication, and sensory abnormalities. Lower Bayley-III language scores and non-white ethnicity were associated with higher Q-CHAT scores.

CONCLUSIONS

Preterm children display greater social-communication difficulty and autistic behavior than the general population in early childhood as assessed by the Q-CHAT. The implications for longer-term outcome will be important to assess.

Screening for autism in preterm children with extremely low and very low birth weight

BACKGROUND

Studies of children with very low birth weight (VLBW, 1,000-1,500 g) and extremely low birth weight (ELBW, less than 1,000 g) indicate that this population seems to be at increased risk of autism spectrum disorder (ASD).

METHODS

Parents of 101 VLBW and ELBW children (age 2 years, corrected for prematurity) agreed to participate in the study and signed informed consents; however, parents of only 75 children (44 boys, 31 girls) completed the screening questionnaires. The screening battery included the Modified Checklist for Autism in Toddlers (M-CHAT), Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC), and the Infant/Toddler Sensory Profile (ITSP). Children with disabilities were excluded. All children who screened positive on any of the screening tools were subsequently invited for a detailed assessment.

RESULTS

Thirty-two children (42.7%) screened positive on at least one of the screening questionnaires. The screening tool with the most positive results was the CSBS-DP-ITC (26 positive screens), followed by the M-CHAT (19 positive screens) and the ITSP (11 positive screens). Of the 32 children who tested positive, 19 participated in the detailed follow-up assessment. A diagnosis of ASD was confirmed in eight of the 19 children. ASD prevalence, calculated from those 19 children and those with negative screening results (43 children), yielded a prevalence of 12.9% in the sample. The difference in frequency of positive screens between the tests was significant (P=0.011). In pair comparisons, ITSP was found to be significantly less positive than CSBS-DP-ITC (P=0.032). No significant differences were found between the M-CHAT and CSBS-DP-ITC or between the M-CHAT and ITSP.

CONCLUSION

The results strongly support the hypothesis of an increased prevalence of autism in children with a birth weight less than 1,500 g.

Comparison of three screening tests for autism in preterm children with birth weights less than 1,500 grams

BACKGROUND

Preterm children seem to be at increased risk for autism spectrum disorders (ASD).

METHODS

Parents of 157 children with birth weights less than 1,500 g (age 2 years, corrected for prematurity; 88 boys, 69 girls) completed screening questionnaires. The screening battery included the Modified Checklist for Autism in Toddlers (M-CHAT), Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC), and the Infant/Toddler Sensory Profile (ITSP). Children with disabilities were excluded. All children who screened positive on any of the screening tools were subsequently assessed by clinical examination including the Autism Diagnostic Observation Schedule.

RESULTS

Fifty-six children (35.7%) screened positive on at least one of the parental screening questionnaires. Of the 56 children who tested positive, 33 participated in the detailed clinical follow-up assessment. A diagnosis of ASD was confirmed in 13 of the 33 children. The ASD prevalence was 9.7% of the sample. Analysis of children with and without an ASD diagnosis found significant differences relative to gestational age (26.9 weeks vs 28.3 weeks, P=0.033) and length of the stay in hospital (89.5 days vs 75.4 days, P=0.042). The screening tool with the most positive results was CSBS-DP-ITC (42 positive screens [PS]), followed by M-CHAT (28 PS), and ITSP (22 PS). Differences in the frequency of PS among the tests were significant (P=0.008). CSBS-DP-ITC had the highest sensitivity (0.846), followed by M-CHAT (0.692) and ITSP (0.462).

CONCLUSION

Our results indicate a higher prevalence of autism in children with birth weights <1,500 g at 2 years of age compared to the general population prevalence. The ASD diagnosis was associated with shorter gestation times and longer hospital stays. Our findings support the simultaneous use of more than one screening tests in order to increase screening sensitivity.