Brief Report: The ADOS Calibrated Severity Score Best Measures Autism Diagnostic Symptom Severity in Pre-School Children

Measuring autism with the ADOS-2 using a bifactor model

The measurement of autism characteristics can be challenging due to variability of social impairments and restricted and repetitive behaviors or interests (RRBs). Psychometrically strong measures such as the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) can improve our capacity for thorough autism assessment. The conceptualization of the ADOS-2 has been shaped by research exploring the structure of its items, which evaluate autism traits associated with social affect and RRBs. Continuously refining our understanding of these items and their relations to other characteristics, such as cognition, is crucial for more accurate autism assessment and diagnosis. This study used data from a sample of 188 school-age children with mostly average cognitive functioning referred for clinical autism evaluations to (1) test the dimensionality of the ADOS-2, Module 3 (appropriate for children with relatively higher verbal ability), across two sets of items (i.e., algorithm only, algorithm with three non-algorithm RRB items) using confirmatory factor analysis (CFA) and (2) examine the relations of cognition to the dimensions tested in the ADOS-2. A bifactor model, featuring a general autism trait and two subfactors (RRB and Social Affect), provided superior fit for algorithm-only and algorithm with three non-algorithm items. Cognitive functioning was not significantly related to the general or specific factors in the model with only algorithm items. While the findings support the validity of the ADOS-2, it may not fully capture RRBs among children referred for autism. This study enhances our understanding of the ADOS-2, highlighting the utility of a bifactor model for characterizing its dimensionality, measuring autism traits with minimal cognitive influence, and identifying its limitations in assessing RRBs.

Associations Among Race, Ethnicity, and Clinical Profiles of Young Children Evaluated for Autism in the Primary Care Setting

OBJECTIVE

Despite long-standing racial and ethnic disparities in autism spectrum (AS) diagnosis, recent research suggests that overall, greater numbers of Black and Latine children are now diagnosed with AS as compared with non-Latine White (NLW) children in some US regions. However, gaps remain in the equitable detection of Black and Latine children with AS without significant developmental impairment. The objective of this study was to determine whether the clinical profiles of young children evaluated for AS across a statewide system of early autism diagnosis in Indiana vary by race and ethnicity.

METHODS

We examined racial and ethnic differences in: (1) AS symptom severity, (2) developmental functioning, (3) adaptive functioning, and (4) behavior problems in a sample of 147 children, aged 14 to 48 months (M = 2.6 years), referred for AS evaluation.

RESULTS

Clinical profiles of young children evaluated differed significantly by race and ethnicity, with Black and Latine children exhibiting lower developmental ( p = 0.008) and adaptive abilities ( p = 0.01) and higher AS symptoms ( p = 0.03) as compared with NLW children.

CONCLUSION

Potential explanations for findings include racial and ethnic differences in family and community awareness and knowledge about AS and follow-through on evaluation referral, both driven by social determinants of health (SDOH) affecting minoritized children. Bias in screening and assessment instruments and clinician surveillance, screening, and referral practices may also underlie differences in clinical profiles of children evaluated. Future research is needed to understand the SDOH that influence AS detection and diagnosis to improve equitable access to early diagnosis and intervention.

A Multi-Trait Multi-Method Examination of Psychometric Instrument Performance in Autism Spectrum Disorder

Anecdotal evidence has suggested that rater-based measures (e.g., parent report) may have strong across-trait/within-individual covariance that detracts from trait-specific measurement precision; rater measurement-related bias may help explain poor correlation within Autism Spectrum Disorder (ASD) samples between rater-based and performance-based measures of the same trait. We used a multi-trait, multi-method approach to examine method-associated bias within an ASD sample (n = 83). We examined performance/rater-instrument pairs for attention, inhibition, working memory, motor coordination, and core ASD features. Rater-based scores showed an overall greater methodology bias (57% of variance in score explained by method), while performance-based scores showed a weaker methodology bias (22%). The degree of inter-individual variance explained by method alone substantiates an anecdotal concern associated with the use of rater measures in ASD.

Clinical correlates of diagnostic certainty in children and youths with Autistic Disorder

BACKGROUND

Clinicians diagnosing autism rely on diagnostic criteria and instruments in combination with an implicit knowledge based on clinical expertise of the specific signs and presentations associated with the condition. This implicit knowledge influences how diagnostic criteria are interpreted, but it cannot be directly observed. Instead, insight into clinicians' understanding of autism can be gained by investigating their diagnostic certainty. Modest correlations between the certainty of an autism diagnosis and symptom load have been previously reported. Here, we investigated the associations of diagnostic certainty with specific items of the ADOS as well as other clinical features including head circumference.

METHODS

Phenotypic data from the Simons Simplex Collection was used to investigate clinical correlates of diagnostic certainty in individuals diagnosed with Autistic Disorder (n = 1511, age 4 to 18 years). Participants were stratified by the ADOS module used to evaluate them. We investigated how diagnostic certainty was associated with total ADOS scores, age, and ADOS module. We calculated the odds-ratios of being diagnosed with the highest possible certainty given the presence or absence of different signs during the ADOS evaluation. Associations between diagnostic certainty and other cognitive and clinical variables were also assessed.

RESULTS

In each ADOS module, some items showed a larger association with diagnostic certainty than others. Head circumference was significantly higher for individuals with the highest certainty rating across all three ADOS modules. In turn, head circumference was positively correlated with some of the ADOS items that were associated with diagnostic certainty, and was negatively correlated with verbal/nonverbal IQ ratio among those assessed with ADOS module 2.

LIMITATIONS

The investigated cohort was heterogeneous, e.g. in terms of age, IQ, language level, and total ADOS score, which could impede the identification of associations that only exist in a subgroup of the population. The variability of the certainty ratings in the sample was low, limiting the power to identify potential associations with other variables. Additionally, the scoring of diagnostic certainty may vary between clinicians.

CONCLUSION

Some ADOS items may better capture the signs that are most associated with clinicians' implicit knowledge of Autistic Disorder. If replicated in future studies, new diagnostic instruments with differentiated weighting of signs may be needed to better reflect this, possibly resulting in better specificity in standardized assessments.

Oculomotor randomness is higher in autistic children and increases with the severity of symptoms

A variety of studies have suggested that at least some children with autism spectrum disorder (ASD) view the world differently. Differences in gaze patterns as measured by eye tracking have been demonstrated during visual exploration of images and natural viewing of movies with social content. Here we analyzed the temporal randomness of saccades and blinks during natural viewing of movies, inspired by a recent measure of "randomness" applied to micro-movements of the hand and head in ASD (Torres et al., 2013; Torres & Denisova, 2016). We analyzed a large eye-tracking dataset of 189 ASD and 41 typically developing (TD) children (1-11 years old) who watched three movie clips with social content, each repeated twice. We found that oculomotor measures of randomness, obtained from gamma parameters of inter-saccade intervals (ISI) and blink duration distributions, were significantly higher in the ASD group compared with the TD group and were correlated with the ADOS comparison score, reflecting increased "randomness" in more severe cases. Moreover, these measures of randomness decreased with age, as well as with higher cognitive scores in both groups and were consistent across repeated viewing of each movie clip. Highly "random" eye movements in ASD children could be associated with high "neural variability" or noise, poor sensory-motor control, or weak engagement with the movies. These findings could contribute to the future development of oculomotor biomarkers as part of an integrative diagnostic tool for ASD.

Expression of miRNAs in Pre-Schoolers with Autism Spectrum Disorders Compared with Typically Developing Peers and Its Effects after Probiotic Supplementation

Alteration of the microbiota-gut-brain axis has been recently recognized as a possible contributor to the physiopathology of autism spectrum disorder (ASD). In this context, microRNA (miRNAs) dysfunction, implicated both in several neuropathological conditions including ASD and in different gastrointestinal disorders (GIDs), could represent an important modulating factor. In this contextual framework, we studied the transcriptional profile of specific circulating miRNAs associated with both ASD (miR-197-5p, miR-424-5p, miR-500a-5p, miR-664a-5p) and GID (miR-21-5p, miR-320a-5p, miR-31-5p, miR-223-5p) in a group of pre-schoolers with ASD and in typically developing (TD) peers. In the ASD group, we also assessed the same miRNAs after a 6-month supplementation with probiotics and their correlation with plasma levels of zonulin and lactoferrin. At baseline, the expression of miRNAs involved in ASD were significantly reduced in ASD pre-schoolers vs. TD controls. Regarding the miRNAs involved in GID, the expression levels of miR-320-5p, miR-31-5p, and miR-223-5p were significantly higher in ASD than in TD subjects, whereas miR-21-5p showed significantly reduced expression in the ASD group vs. TD group. Supplementation with probiotics did not significantly change the expression of miRNAs in the ASD population. We found a significative negative correlation between zonulin and miR-197-5p and miR-21-5p at baseline, as well as between lactoferrin and miR-223-5p after 6 months of probiotic supplementation. Our study confirms the presence of an altered profile of the miRNAs investigated in ASD versus TD peers that was not modified by supplementation with probiotics.

In Search of Biomarkers to Guide Interventions in Autism Spectrum Disorder: A Systematic Review

OBJECTIVE

The aim of this study was to catalog and evaluate response biomarkers correlated with autism spectrum disorder (ASD) symptoms to improve clinical trials.

METHODS

A systematic review of MEDLINE, Embase, and Scopus was conducted in April 2020. Seven criteria were applied to focus on original research that includes quantifiable response biomarkers measured alongside ASD symptoms. Interventional studies or human studies that assessed the correlation between biomarkers and ASD-related behavioral measures were included.

RESULTS

A total of 5,799 independent records yielded 280 articles for review that reported on 940 biomarkers, 755 of which were unique to a single publication. Molecular biomarkers were the most frequently assayed, including cytokines, growth factors, measures of oxidative stress, neurotransmitters, and hormones, followed by neurophysiology (e.g., EEG and eye tracking), neuroimaging (e.g., functional MRI), and other physiological measures. Studies were highly heterogeneous, including in phenotypes, demographic characteristics, tissues assayed, and methods for biomarker detection. With a median total sample size of 64, almost all of the reviewed studies were only powered to identify biomarkers with large effect sizes. Reporting of individual-level values and summary statistics was inconsistent, hampering mega- and meta-analysis. Biomarkers assayed in multiple studies yielded mostly inconsistent results, revealing a "replication crisis."

CONCLUSIONS

There is currently no response biomarker with sufficient evidence to inform ASD clinical trials. This review highlights methodological imperatives for ASD biomarker research necessary to make definitive progress: consistent experimental design, correction for multiple comparisons, formal replication, sharing of sample-level data, and preregistration of study designs. Systematic "big data" analyses of multiple potential biomarkers could accelerate discovery.

Autism spectrum disorder and dentoalveolar trauma: A systematic review and meta-analysis

OBJECTIVES

Patients with autism spectrum disorder (ASD) may be more predisposed to oral pathology, including dentoalveolar trauma. Our aim was to assess the risk of dentoalveolar trauma in patients with ASD.

MATERIALS AND METHODS

Meta-analysis methodology was used to compare the prevalence of dentoalveolar trauma in individuals with ASD compared to individuals without ASD. A literature search was carried out, with predefined inclusion and exclusion criteria, to identify controlled studies evaluating dentoalveolar trauma in individuals with ASD. Data were combined using the random-effects meta-analysis model.

RESULTS

Out of an initial 154 studies, 14 were selected for inclusion in the meta-analysis, resulting in a total of 1488 individuals with ASD. Meta-analysis results showed significant difference in the overall risk of dentoalveolar trauma between individuals with ASD versus a control group (RR = 1.45). Looking at specific types of dentoalveolar trauma, individuals with ASD were found to be more at risk for partial or total (avulsion) luxation injuries (RR = 3.02) than healthy individuals.

CONCLUSIONS

Individuals with ASD are more at risk for dentoalveolar trauma than those without ASD, especially for more severe dentoalveolar trauma such as luxation and avulsion injuries.

Vitamin D Status in Children with Autism Spectrum Disorders: Determinants and Effects of the Response to Probiotic Supplementation

A relationship between the presence of clinical symptoms and gastrointestinal (GI) disturbances associated with nutritional deficiencies, including vitamin D (25(OH)D) deficiency, has been observed in autism spectrum disorder (ASD). The aim was to evaluate 25(OH)D levels according to the annual rhythm cycle, gender, the severity of autism, nutritional or clinical status, inflammatory and metabolic biomarkers, GI symptoms, and the clinical response to probiotic/placebo supplementation in preschooler children with ASD. Eighty-one ASD preschoolers (67 males) were assessed with standardized tools for ASD severity (ADOS score) and GI symptoms (by GI-Index at six-items and at nine-items, the latter defined as the Total GI-Index). The 25(OH)D levels were compared among different ASD subgroups according to metabolic and inflammatory biomarkers (leptin, insulin, resistin, PAI-1, MCP-1, TNF-alfa, and IL-6), gender, and the presence or absence of: (i) GI symptoms, (ii) the response to probiotic supplementation (the improvement of GI symptomatology), (iii) the response to probiotic supplementation (improvement of ASD severity). Only 25% of the ASD children presented an adequate 25(OH)D status (≥30 ng/mL according to the Endocrine Society guidelines). All the 25(OH)D levels falling in the severe deficiency range (<10 ng/mL) were observed in the male subgroup. A significant inverse correlation between 25(OH)D and leptin was observed (R = −0.24, p = 0.037). An inverse correlation was found between 25(OH)D levels and the GI Index 6-Items and Total GI-Index (R = −0.25, p = 0.026; −0.27, = 0.009) and a direct relationship with the probiotic response (R = 0.4, p = 0.05). The monitoring of 25(OH)D levels and the co-administration of 25(OH)D and probiotic supplementation could be considered in ASD from early ages.

The Diagnosis of Autism: From Kanner to DSM-III to DSM-5 and Beyond

In this paper we review the impact of DSM-III and its successors on the field of autism-both in terms of clinical work and research. We summarize the events leading up to the inclusion of autism as a "new" official diagnostic category in DSM-III, the subsequent revisions of the DSM, and the impact of the official recognition of autism on research. We discuss the uses of categorical vs. dimensional approaches and the continuing tensions around broad vs. narrow views of autism. We also note some areas of current controversy and directions for the future.

Brief Report: Emotional and Behavioral Problems Among Young Children with ASD: An Exploratory Study of ADOS E-Codes and Child Characteristics

Emotional and behavioral problems (EBPs), such as anxiety, overactivity, and aggression, can influence the diagnosis of autism spectrum disorder (ASD). The gold standard diagnostic tool for ASD, the Autism Diagnostic Observation Schedule-Second Edition, includes three items ("E-codes") for EBPs that are frequently associated with ASD. Few empirical investigations have explored the use of E-codes. This study examined the relationship between E-codes and child characteristics (e.g., cognitive abilities, ASD symptom severity) in a sample of young children with ASD (N = 233). Findings indicated that E-codes positively correlated with ASD symptom severity and negatively associated with IQ. Symptom severity also significantly accounted for the variance in EBPs. Implications for ASD assessment as well as future research are discussed.

The Curious Case of Lennox-Gastaut Syndrome: Treatment-Resistant Seizures in a Patient With Autism Spectrum Disease With Lennox-Gastaut Syndrome

Lennox-Gastaut syndrome (LGS) is a childhood epilepsy disorder seen between the ages of one to eight years with the electroencephalogram (EEG) changes showing slow spiked-wave complex bursts or paroxysms of generalized fast activity and intellectual disability and often needing multiple lines of treatment. Autism spectrum disease (ASD) is rare but catastrophic comorbidity seen in a patient with LGS. We report an eight-year-old boy presenting to the emergency department with seizures and mental retardation. His first seizure was at the age of five months but was symptomatically treated without any specific diagnosis. On further investigation, the patient was diagnosed with LGS with concomitant ASD. The patient has successfully been treated for his treatment-resistant seizures and is now on regular follow-ups. This article aims to highlight this rare combination of LGS along with ASD and understand the disease course.

Association between prenatal and perinatal factors and the severity of clinical presentation of children with ASD: Report from the ELENA COHORT

Many studies have suggested that prenatal and perinatal factors increase the risk for autism spectrum disorder (ASD). However, few reports have addressed the question of their influence on the severity of the clinical presentation of children with ASD. Our objective was to determine the prenatal and perinatal factors that are associated with the severity of autistic symptoms and intellectual and adaptive functioning deficits. Data were collected from a subset of 169 children with a confirmed diagnosis of ASD, recruited from the ELENA cohort. A risk of premature delivery was associated, with an increased risk for severe autistic symptoms and placental pathologies and birth complications were associated with an increased risk of communication adaptive deficits, in multivariate analysis. Our results highlight the importance of systematic screening for these pre/perinatal factors, especially in mothers at risk of having a child with ASD.

Sleep Disturbances and Sensory Sensitivities Co-Vary in a Longitudinal Manner in Pre-School Children with Autism Spectrum Disorders

Previous research has demonstrated that sleep disturbances are positively correlated with sensory sensitivities in children with ASD. Most of these studies, however, were based on cross-sectional analyses, where the relationship across symptom domains was examined at a single time-point. Here, we examined the development of 103 pre-school children with ASD over a 1–3-year period. The results revealed that spontaneous longitudinal changes in sleep disturbances were specifically correlated with changes in sensory sensitivities and not with changes in other sensory processing domains nor with changes in core ASD symptoms. These finding demonstrate a consistent longitudinal relationship between sleep disturbances and sensory sensitivities, which suggests that these symptoms may be generated by common or interacting underlying physiological mechanisms.

Brief Report: Examining Test-Retest Reliability of the Autism Diagnostic Observation Schedule (ADOS-2) Calibrated Severity Scores (CSS)

Describing the relative severity and change in autism symptoms is crucial for the appropriate characterization of clinical and research populations. The calibrated severity score (CSS) of the Autism Diagnostic Observation Schedule-2 (ADOS-2; Lord et al., 2012) was created to better describe autism symptom severity consistently across different ages and language levels. The CSS has been widely used to quantify and compare symptom severity on a 10-point scale across Modules; however, its test re-test reliability has not been studied. With 608 ADOS observations, we showed strong test re-test reliability of the CSS across all ADOS Modules. The results support the use of the ADOS CSS as a reliable tool to quantify autism symptom severity across development.

Early Life Exposure to Air Pollution and Autism Spectrum Disorder: Findings from a Multisite Case-Control Study

BACKGROUND

Epidemiologic studies have reported associations between prenatal and early postnatal air pollution exposure and autism spectrum disorder (ASD); however, findings differ by pollutant and developmental window.

OBJECTIVES

We examined associations between early life exposure to particulate matter ≤2.5 µm in diameter (PM2.5) and ozone in association with ASD across multiple US regions.

METHODS

Our study participants included 674 children with confirmed ASD and 855 population controls from the Study to Explore Early Development, a multi-site case-control study of children born from 2003 to 2006 in the United States. We used a satellite-based model to assign air pollutant exposure averages during several critical periods of neurodevelopment: 3 months before pregnancy; each trimester of pregnancy; the entire pregnancy; and the first year of life. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for study site, maternal age, maternal education, maternal race/ethnicity, maternal smoking, and month and year of birth.

RESULTS

The air pollution-ASD associations appeared to vary by exposure time period. Ozone exposure during the third trimester was associated with ASD, with an OR of 1.2 (95% CI: 1.1, 1.4) per 6.6 ppb increase in ozone. We additionally observed a positive association with PM2.5 exposure during the first year of life (OR = 1.3 [95% CI: 1.0, 1.6] per 1.6 µg/m increase in PM2.5).

CONCLUSIONS

Our study corroborates previous findings of a positive association between early life air pollution exposure and ASD, and identifies a potential critical window of exposure during the late prenatal and early postnatal periods.

A SWOT analysis of parent-mediated intervention for children with autism spectrum disorder: Oman as a Regional Model

The prevalence of autism in the Arabian Gulf region is on the rise leading to overstretching of the pre-existing intervention services. The World Health Organization Caregiver Skills Training Program is a novel renovation being studied around the globe to overcome the scarcity of resources, improve autistic children's outcome and empower parents with comparable results to therapist-based models. Recently, Oman achieved great success in advocating for autism and initiated the first screening program for autism in the region. This review aims to use a Strength, Weakness, Opportunities and Threats (SWOT) analysis matrix to investigate the potential for using a parent-mediated intervention program as a supplementary approach to the currently used therapist-based intervention model in the country as an example for Gulf region.

Individual and Environmental Factors Affecting Adaptive Behavior of Toddlers with Autism Spectrum Disorder: Role of Parents' Socio-cultural Level

The effects of environmental factors [including Socio-Economic Status, Cultural Capital, and Social Capital (Socio-Cultural Level) of both parents] on the Vineland-II adaptive behavior dimensions of toddlers with autism spectrum disorder (ASD), in addition to individual factors, was investigated in 148 Italian toddlers (82% males), aged 18 to 37 months with ASD. Toddlers’ age and Griffiths Mental Development Scales general development affected all of the adaptive behavior dimensions, with negative and positive associations, respectively. The Child Behavior Checklist comorbid conditions were negatively associated with some adaptive behavior dimensions while the ADOS-2 Social affect only with the communication dimension. Mothers’ and fathers’ specific Socio-Cultural Level dimensions were positively associated with toddlers’ specific adaptive behavior dimensions with the same magnitude as comorbid conditions.

Effects of Probiotic Supplementation on Gastrointestinal, Sensory and Core Symptoms in Autism Spectrum Disorders: A Randomized Controlled Trial

The microbiota-gut-brain axis has been recently recognized as a key modulator of neuropsychiatric health. In this framework, probiotics (recently named "psychobiotics") may modulate brain activity and function, possibly improving the behavioral profiles of children with Autism Spectrum Disorder (ASD). We evaluated the effects of probiotics on autism in a double-blind randomized, placebo-controlled trial of 85 preschoolers with ASD (mean age, 4.2 years; 84% boys). Participants were randomly assigned to probiotics (De Simone Formulation) (n=42) or placebo (n=43) for six months. Sixty-three (74%) children completed the trial. No differences between groups were detected on the primary outcome measure, the Total Autism Diagnostic Observation Schedule - Calibrated Severity Score (ADOS-CSS). An exploratory secondary analysis on subgroups of children with or without Gastrointestinal Symptoms (GI group, n= 30; NGI group, n=55) revealed in the NGI group treated with probiotics a significant decline in ADOS scores as compared to that in the placebo group, with a mean reduction of 0.81 in Total ADOS CSS and of 1.14 in Social-Affect ADOS CSS over six months. In the GI group treated with probiotics we found greater improvements in some GI symptoms, adaptive functioning, and sensory profiles than in the GI group treated with placebo. These results suggest potentially positive effects of probiotics on core autism symptoms in a subset of ASD children independent of the specific intermediation of the probiotic effect on GI symptoms. Further studies are warranted to replicate and extend these promising findings on a wider population with subsets of ASD patients which share targets of intervention on the microbiota-gut-brain axis.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier NCT02708901.

The Role of Demographics in the Age of Autism Diagnosis in Jerusalem

Early diagnosis of autism spectrum disorder (ASD) in children enables earlier access to services and better ability to predict subsequent development. A vast body of literature consistently shows discrepancies in the age of diagnosis between children from varying socio-economic levels, cultural and ethnic backgrounds. The present study examines the effect of sociodemographic factors on age of ASD diagnosis among the three primary ethnic sectors in Jerusalem region: secular and modern religious Jews, ultra-Orthodox Jews and Arabs. Findings indicate minimal differences in age of diagnosis prior to the age of six, although Arab children of this age were largely minimally verbal. After age six, no Arab children were referred for an evaluation.

Relationship of Weight Outcomes, Co-Occurring Conditions, and Severity of Autism Spectrum Disorder in the Study to Explore Early Development

OBJECTIVE

To assess contributing factors to increased obesity risk, by comparing children with autism spectrum disorder (ASD), developmental delays/disorders, and general population controls in weight status, and to examine associations between weight status and presence of co-occurring medical, behavioral, developmental, or psychiatric conditions across groups and ASD severity among children with ASD.

STUDY DESIGN

The Study to Explore Early Development is a multisite cross-sectional study of children, 2-5 years of age, classified as children with ASD (n = 668), children with developmental delays/disorders (n = 914), or general population controls (n = 884). Using an observational cohort design, we compared the 3 groups. Children's heights and weights were measured during a clinical visit. Co-occurring conditions (medical, behavioral, developmental/psychiatric) were derived from medical records, interviews, and questionnaires. ASD severity was measured by the Ohio State University Global Severity Scale for Autism.

RESULTS

The odds of overweight/obesity were 1.57 times (95% CI 1.24-2.00) higher in children with ASD than general population controls and 1.38 times (95% CI 1.10-1.72) higher in children with developmental delays/disorders than general population controls. The aORs were elevated for children with ASD after controlling for child co-occurring conditions (ASD vs general population controls: aOR = 1.51; 95% CI 1.14-2.00). Among children with ASD, those with severe ASD symptoms were 1.7 times (95% CI 1.1-2.8) more likely to be classified as overweight/obese compared with children with mild ASD symptoms.

CONCLUSIONS

Prevention of excess weight gain in children with ASD, especially those with severe symptoms, and in children with developmental delays/disorders represents an important target for intervention.

Social Skills Deficits in Autism Spectrum Disorder: Potential Biological Origins and Progress in Developing Therapeutic Agents

Autism spectrum disorder is defined by two core symptoms: a deficit in social communication and the presence of repetitive behaviors and/or restricted interests. Currently, there is no US Food and Drug Administration-approved drug for these core symptoms. This article reviews the biological origins of the social function deficit associated with autism spectrum disorder and the drug therapies with the potential to treat this deficit. A review of the history of autism demonstrates that a deficit in social interaction has been the defining feature of the concept of autism from its conception. Abnormalities identified in early social skill development and an overview of the pathophysiology abnormalities associated with autism spectrum disorder are discussed as are the abnormalities in brain circuits associated with the social function deficit. Previous and ongoing clinical trials examining agents that have the potential to improve social deficits associated with autism spectrum disorder are discussed in detail. This discussion reveals that agents such as oxytocin and propranolol are particularly promising and undergoing active investigation, while other agents such as vasopressin agonists and antagonists are being activity investigated but have limited published evidence at this time. In addition, agents such as bumetanide and manipulation of the enteric microbiome using microbiota transfer therapy appear to have promising effects on core autism spectrum disorder symptoms including social function. Other pertinent issues associated with developing treatments in autism spectrum disorder, such as disease heterogeneity, high placebo response rates, trial design, and the most appropriate way of assessing effects on social skills (outcome measures), are also discussed.

Screening for Autism with the SRS and SCQ: Variations across Demographic, Developmental and Behavioral Factors in Preschool Children

The Social Communication Questionnaire (SCQ) and the Social Responsiveness Scales (SRS) are commonly used screeners for autism spectrum disorder (ASD). Data from the Study to Explore Early Development were used to examine variations in the performance of these instruments by child characteristics and family demographics. For both instruments, specificity decreased as maternal education and family income decreased. Specificity was decreased with lower developmental functioning and higher behavior problems. This suggests that the false positive rates of the SRS and the SCQ are associated with child characteristics and family demographic factors. There is a need for ASD screeners that perform well across socioeconomic and child characteristics. Clinicians should be mindful of differential performance of these instruments in various groups of children.

Factors influencing the severity of behavioral phenotype in autism spectrum disorders: Implications for research

The phenotypic heterogeneity of Autism Spectrum Disorders (ASD) presents particular research challenges in the assessment of symptom severity, while the standardized Autism Diagnostic Observation Schedule (ADOS) scores present a severity metric, namely calibrated severity scores (CSS) that are relatively impervious to individual characteristics. To date, no studies have examined the convergent validity of CSS in Chinese sample populations. The present study investigated the validity of the ADOS-CSS using a sample of 321 children aged 2-18 years with ASD, and developed upon existing literature examining the influence of non-ASD-specific characteristics on other types of measures including Autism Diagnostic Interview-Revised (ADI-R), Social Responsiveness Scale (SRS), and Vineland Adaptive Behavior Scales (VABS). As expected, the findings revealed that the CSS were less influenced than ADOS-RAW scores by the demographic and developmental-level variables. Moreover, compared to the ADOS-CSS, the ADI-R, SRS and VABS were still strongly correlated with confounding factors, such as chronological age, intelligence quotients, and language-level. The results of this study corroborate the utilization of CSS as a more valid indicator of ASD severity than raw scores from ADOS and other instruments.

Autism spectrum disorder and birth spacing: Findings from the study to explore early development (SEED)

Previous studies of autism spectrum disorder (ASD) and birth spacing had limitations; few examined phenotypic case subtypes or explored underlying mechanisms for associations and none assessed whether other (non-ASD) developmental disabilities (DDs) were associated with birth spacing. We assessed associations between inter-pregnancy interval (IPI) and both ASD and other DDs using data from the Study to Explore Early Development, a multi-site case-control study with rigorous case-finding and case-classification methods and detailed data collection on maternal reproductive history. Our sample included 356 ASD cases, 627 DD cases, and 524 population (POP) controls born in second or later births. ASD and DD cases were further sub-divided according to whether the child had intellectual disability (ID). ASD cases were also sub-divided by ASD symptom severity, and DD cases were subdivided by presence of some ASD symptoms (indicated on an autism screener). Odds ratios, adjusted for maternal-child sociodemographic factors, (aORs) and 95% confidence intervals were derived from logistic regression models. Among term births, ASD was associated with both IPI <18 months (aOR 1.5 [1.1-2.2]) and ≥60 months (1.5 [0.99-2.4]). Both short and long IPI associations were stronger among ASD cases with high severity scores (aORs 2.0 [1.3-3.3] and 1.8 [0.99-3.2], respectively). Associations were unchanged after adding several factors potentially related to the causal pathway to regression models. DD was not associated with either short or long IPI-overall, among term births, or in any subgroup examined. These findings extend those from previous studies and further inform recommendations on optimal pregnancy spacing. Autism Res 2018, 11: 81-94. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

We investigated whether the amount of time between pregnancies was associated autism spectrum disorder (ASD) or other developmental disabilities (DD) in children. ASD was increased in second and later-born children who were conceived less than 18 months or 60 or more months after the mother's previous birth. Other DDs were not associated with birth spacing.

The prevalence of gluten free diet use among preschool children with autism spectrum disorder

Our objective was to estimate prevalence of current or ever use of a gluten free diet (GFD) in children aged 30-68 months with autism spectrum disorder (ASD) and population controls (POP); and to identify characteristics associated with ever having used GFD among children with ASD. We used data from the Study to Explore Early Development (SEED), a multi-site, case-control study of children with ASD. Caregivers reported GFD use by their children through structured questionnaires about diet patterns, gastrointestinal (GI) issues, and ASD-specific treatments. Prevalence was estimated and compared using log-Poisson regression, adjusting for confounders. In children with ASD, we examined whether child or mother's GI conditions or child's phenotypic traits were associated with ever trying a GFD. In SEED, 71 children with ASD (11.1% prevalence after adjustment) were on a GFD at time of the study and 130 (20.4%) had ever used a GFD, a greater percentage than in POP children (N = 11, 0.9% current use). Of current users with ASD, 50.7% had a dietary intervention that was prescribed by a medical professional. Among children with ASD, child GI conditions and developmental regression were positively and independently associated with having ever used a GFD. Current use and ever use of a GFD were prevalent in children with ASD identified in SEED. GFD usage was associated with GI issues and child phenotype. Clinicians may consider advising parents on how best to use these diets in the context of the child's GI presentation and current scientific knowledge about effectiveness in relation to ASD symptoms. Autism Res 2018, 11: 185-193. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

Gluten free diets (GFDs) are commonly used as an alternative therapy for autism spectrum disorder (ASD); however, the effectiveness is still uncertain which makes it important to know who tries this type of diet. We found that one in five preschool aged children with ASD had ever used a GFD. Children with gastrointestinal conditions and developmental regression were more likely to have tried a GFD.