Changes in autism spectrum disorder prevalence in 4 areas of the United States

Prevalence of Autism Spectrum Disorder in Children in Andalusia (Spain)

Autism Spectrum Disorder (ASD) is socially relevant because of its number and the intensity of the medical and socio-educational response it requires. In Andalusia, one in 70 children will be diagnosed with ASD in 2021. It is much more frequent in boys than in girls, being 5.91 times more likely to present it as a boy than as a girl. The age of diagnosis is increasingly younger, standing at 4.4 years. In more than half of primary schools and more than 75% of secondary schools there are an average of three students with ASD per school. It is necessary to develop a network of preferential care centers for students with ASD to generalize specialized care in ordinary modalities.

Patterns of Special Education Eligibility and Age of First Autism Spectrum Disorder (ASD) Identification Among US Children with ASD

The study examined timing of autism spectrum disorder (ASD) identification in education versus health settings for 8-year-old children with ASD identified through records-based surveillance. The study also examined type of ASD symptoms noted within special education evaluations. Results indicated that children with records from only education sources had a median time to identification of ASD over a year later than children with records from health sources. Black children were more likely than White children to have records from only education sources. Restricted and repetitive behaviors were less frequently documented in educational evaluations resulting in developmental delay eligibility compared to specific ASD eligibility among children with ASD. Future research could explore strategies reduce age of identification in educational settings and increase equitable access to health evaluations.

Self-rated familiarity with autism spectrum disorders among practicing nurses: a cross-sectional study in the palestinian nursing practice

Background

Autism spectrum disorders (ASDs) are one of the most prevalent neurodevelopmental disabilities of early childhood. Practicing nurses are in a key position to help patients with ASDs and/or their caregivers/families. This study was conducted to assess self-rated familiarity with ASDs among practicing nurses in Palestine. The study also aimed to identify the sociodemographic and practice variables that could predict high self-rated familiarity scores.

Methods

This was a cross-sectional study using a questionnaire. The study was conducted in the period between January 2019 and May 2019. The questionnaire collected: 1) the sociodemographic, pedagogic, and practice variables of the nurses, 2) their self-rated familiarity with signs and symptoms, treatment options, and community resources of ASDs, 3) their self-rated confidence in their abilities to provide counseling for parents/family/caregivers on the drugs prescribed for children/patients with ASDs and their potential adverse effects, and 4) their willingness to receive education/training on issues in ASDs.

Results

The questionnaire was completed by 357 practicing nurses. The practicing nurses self-reported inadequate familiarity with symptoms, treatment, and community resources of ASDs. The mean familiarity score was 35.8% (SD: 18.9%). The nurses also expressed low confidence in their ability to provide counseling services to caregivers/families of children with ASDs. About 75% of the nurses agreed that they could benefit from taking a continuing educational/training program in the area of ASDs and about 82% of the nurses agreed that the nursing school curriculum should include courses in the area of ASDs. The multiple linear regression model showed that higher familiarity scores were predicted by having longer practical experience, having a higher academic degree in nursing, and having a continuing educational course/program on ASDs.

Conclusion

Findings of this study highlighted inadequate familiarity with issues of ASDs among practicing nurses. Higher familiarity was predicted by the length of practical experience, higher academic degree in nursing, and having continuing educational course/program on ASDs. Specifically designed pedagogic interventions might be helpful in increasing familiarity of practicing nurses on ASDs. More investigations are still needed to evaluate if these interventions can improve familiarity and services provided to patients with ASDs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12912-021-00764-3.

Genetic counseling as preventive intervention: toward individual specification of transgenerational autism risk

BACKGROUND

Although autism spectrum disorders (ASD) are among the most heritable of all neuropsychiatric syndromes, most affected children are born to unaffected parents. Recently, we reported an average increase of 3-5% over general population risk of ASD among offspring of adults who have first-degree relatives with ASD in a large epidemiologic family sample. A next essential step is to investigate whether there are measurable characteristics of individual parents placing them at higher or lower recurrence risk, as this information could allow more personalized genetic counseling.

METHODS

We assembled what is to our knowledge the largest collection of data on the ability of four measurable characteristics of unaffected prospective parents to specify risk for autism among their offspring: (1) sub clinical autistic trait burden, (2) parental history of a sibling with ASD, (3) transmitted autosomal molecular genetic abnormalities, and (4) parental age. Leveraging phenotypic and genetic data in curated family cohorts, we evaluate the respective associations between these factors and child outcome when autism is present in the family in the parental generation.

RESULTS

All four characteristics were associated with elevation in offspring risk; however, the magnitude of their predictive power-with the exception of isolated rare inherited pathogenic variants -does not yet reach a threshold that would typically be considered actionable for reproductive decision-making.

CONCLUSIONS

Individual specification of risk to offspring of adults in ASD-affected families is not straightforwardly improved by ascertainment of parental phenotype, and it is not yet clear whether genomic screening of prospective parents in families affected by idiopathic ASD is warranted as a clinical standard. Systematic screening of affected family members for heritable pathogenic variants, including rare sex-linked mutations, will identify a subset of families with substantially elevated transmission risk. Polygenic risk scores are only weakly predictive at this time but steadily improving and ultimately may enable more robust prediction either singly or when combined with the risk variables examined in this study.

Brief Report: Impact of the COVID-19 Pandemic on Asian American Families with Children with Developmental Disabilities

Discrimination against Asians and Asian Americans increased during the COVID-19 pandemic. Yet, even prior to the pandemic, little research explored the experiences of Asian American families of children with autism and other developmental disabilities. This brief report summarizes the results of a survey conducted between May and July 2020, in the immediate aftermath of state and local lockdowns due to the pandemic. Twenty-five Asian American caregivers of children with autism and other developmental disabilities completed the survey and reported on the pandemic's impact on their household. Most of the caregivers were mothers, immigrants, Chinese, raising children with autism, and highly educated. Participants' primary concerns were the disruption of their children's educational and therapeutic services. We discuss research limitations and implications.

Parent stress and coping trajectories in Hispanic and non-Hispanic families of children at risk of autism spectrum disorder

LAY ABSTRACT

Little is known about parent experiences throughout the diagnostic process for autism or how these parent experiences may help explain the disparities that exist between Hispanic and non-Hispanic families in time-to-diagnosis among children identified as at risk for autism. The current study examined trajectories of parenting stress, coping, and perceived family impact over time, throughout the autism diagnostic process among Hispanic and non-Hispanic families. Hispanic families reported lower levels of parenting stress, coping, and negative family impact across time. Further, there were differences in the change in use of coping and the amount of negative family impact reported between Hispanic and non-Hispanic parents over time. These differences shed light on the unique experiences and strengths of Hispanic families demonstrate. Interventions that leverage those strengths and focus on education, empowerment, and resilience might be particularly beneficial for Hispanic families and may also better inform work to increase resilience.

Prevalence and Correlates of Work Experiences Among High School Students on the Autism Spectrum

This study used nationally representative data to describe the prevalence and correlates of work experiences among high school students with autism who received special education. Four in tenstudents with autism experienced any type of work (community-based, school-sponsored, paid or unpaid) within a given year-significantly fewer than peers with and without disabilities. Rates of paid work among students with autism were comparable to students with intellectual disability (ID)but half the rate of non-special education peers. Among youth with autism, significant correlates of having work experiences included being white, parent participation in transition planning, and functional skills including navigation. Fostering a variety of early work experiences should be a key goal of disability employment policy at federal and state levels.

Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years - Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2016

PROBLEM/CONDITION

Autism spectrum disorder (ASD).

PERIOD COVERED

2016.

DESCRIPTION OF SYSTEM

The Autism and Developmental Disabilities Monitoring (ADDM) Network is an active surveillance program that provides estimates of the prevalence of ASD among children aged 8 years whose parents or guardians live in 11 ADDM Network sites in the United States (Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri, New Jersey, North Carolina, Tennessee, and Wisconsin). Surveillance is conducted in two phases. The first phase involves review and abstraction of comprehensive evaluations that were completed by medical and educational service providers in the community. In the second phase, experienced clinicians who systematically review all abstracted information determine ASD case status. The case definition is based on ASD criteria described in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.

RESULTS

For 2016, across all 11 sites, ASD prevalence was 18.5 per 1,000 (one in 54) children aged 8 years, and ASD was 4.3 times as prevalent among boys as among girls. ASD prevalence varied by site, ranging from 13.1 (Colorado) to 31.4 (New Jersey). Prevalence estimates were approximately identical for non-Hispanic white (white), non-Hispanic black (black), and Asian/Pacific Islander children (18.5, 18.3, and 17.9, respectively) but lower for Hispanic children (15.4). Among children with ASD for whom data on intellectual or cognitive functioning were available, 33% were classified as having intellectual disability (intelligence quotient [IQ] ≤70); this percentage was higher among girls than boys (39% versus 32%) and among black and Hispanic than white children (47%, 36%, and 27%, respectively) [corrected]. Black children with ASD were less likely to have a first evaluation by age 36 months than were white children with ASD (40% versus 45%). The overall median age at earliest known ASD diagnosis (51 months) was similar by sex and racial and ethnic groups; however, black children with IQ ≤70 had a later median age at ASD diagnosis than white children with IQ ≤70 (48 months versus 42 months).

INTERPRETATION

The prevalence of ASD varied considerably across sites and was higher than previous estimates since 2014. Although no overall difference in ASD prevalence between black and white children aged 8 years was observed, the disparities for black children persisted in early evaluation and diagnosis of ASD. Hispanic children also continue to be identified as having ASD less frequently than white or black children.

PUBLIC HEALTH ACTION

These findings highlight the variability in the evaluation and detection of ASD across communities and between sociodemographic groups. Continued efforts are needed for early and equitable identification of ASD and timely enrollment in services.

Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years - Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2016

PROBLEM/CONDITION

Autism spectrum disorder (ASD).

PERIOD COVERED

2016.

DESCRIPTION OF SYSTEM

The Autism and Developmental Disabilities Monitoring (ADDM) Network is an active surveillance program that provides estimates of the prevalence of ASD among children aged 8 years whose parents or guardians live in 11 ADDM Network sites in the United States (Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri, New Jersey, North Carolina, Tennessee, and Wisconsin). Surveillance is conducted in two phases. The first phase involves review and abstraction of comprehensive evaluations that were completed by medical and educational service providers in the community. In the second phase, experienced clinicians who systematically review all abstracted information determine ASD case status. The case definition is based on ASD criteria described in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.

RESULTS

For 2016, across all 11 sites, ASD prevalence was 18.5 per 1,000 (one in 54) children aged 8 years, and ASD was 4.3 times as prevalent among boys as among girls. ASD prevalence varied by site, ranging from 13.1 (Colorado) to 31.4 (New Jersey). Prevalence estimates were approximately identical for non-Hispanic white (white), non-Hispanic black (black), and Asian/Pacific Islander children (18.5, 18.3, and 17.9, respectively) but lower for Hispanic children (15.4). Among children with ASD for whom data on intellectual or cognitive functioning were available, 33% were classified as having intellectual disability (intelligence quotient [IQ] ≤70); this percentage was higher among girls than boys (39% versus 32%) and among black and Hispanic than white children (47%, 36%, and 27%, respectively) [corrected]. Black children with ASD were less likely to have a first evaluation by age 36 months than were white children with ASD (40% versus 45%). The overall median age at earliest known ASD diagnosis (51 months) was similar by sex and racial and ethnic groups; however, black children with IQ ≤70 had a later median age at ASD diagnosis than white children with IQ ≤70 (48 months versus 42 months).

INTERPRETATION

The prevalence of ASD varied considerably across sites and was higher than previous estimates since 2014. Although no overall difference in ASD prevalence between black and white children aged 8 years was observed, the disparities for black children persisted in early evaluation and diagnosis of ASD. Hispanic children also continue to be identified as having ASD less frequently than white or black children.

PUBLIC HEALTH ACTION

These findings highlight the variability in the evaluation and detection of ASD across communities and between sociodemographic groups. Continued efforts are needed for early and equitable identification of ASD and timely enrollment in services.

Autism Identity and the "Lost Generation": Structural Validation of the Autism Spectrum Identity Scale (ASIS) and Comparison of Diagnosed and Self-Diagnosed Adults on the Autism Spectrum

Background

A population segment of autistic adults are under-identified due, in part, to historic changes in criteria for diagnosing autism and diagnostic biases related to gender, socioeconomic status, and other individual characteristics such as intellectual functioning. Some of these individuals, described as the "lost generation", may choose to self-diagnose. Although little is known about this population, it is possible that they share similar self-conceptualizations or internalized stigma as their diagnosed counterparts. This study reports on the structural validity of the Autism Spectrum Identity Scale (ASIS) with individuals diagnosed and self-diagnosed with autism and compares the demographic characteristics, stigma, self-concept, and quality of life of these two groups.

Methods

Over 1000 adults diagnosed (n = 893) or self-diagnosed (n = 245) with autism were recruited through organizations serving the autism community to participate in a nationally distributed online survey that included demographic questions and measures for stigma, self-concept, quality of life, and wellbeing. The diagnosed dataset was randomly split with exploratory factor analysis performed on a training dataset. Split-half cross-validation was used to predict the factor structure of the holdout dataset. Then, the full diagnosed dataset structure was used to determine the generalizability of the factor structure to the self-diagnosed dataset. The diagnosed and self-diagnosed were also compared for differences in gender, age, employment status, diagnostic term preference, and factors of self-concept (autism identity and self-esteem), stigma, and quality of life.

Results

Factor analysis of diagnosed participants yielded a four-factor structure, consistent with previous research, with strong split-sample cross-validation and good internal consistency. Factor predictions of the self-diagnosed dataset from the diagnosed dataset ranged from .97 - 1.00 with similar internal consistency. Self-diagnosed participants were more likely to be older, women, or employed and less likely to be students or prefer the term "autism" than those with an autism diagnosis. The groups were remarkably similar in reported stigma, self-esteem, quality of life and in ASIS factors; both groups reported lower quality of life than the general population.

Conclusions

The ASIS demonstrated the same internal structure with both the diagnosed and self-diagnosed. The profile of self-diagnosed participants matches the profile hypothesized for the "lost generation" and others at risk of being under-identified for autism. Both populations appear to be similarly struggling with employment, stigma, and quality of life. Future research should examine whether self-diagnosed individuals meet criteria for autism or could benefit from interventions, programs, or services serving autism communities.

Neighbourhood-level prevalence of teacher-reported Autism Spectrum Disorder among kindergarten children in Canada: A population level study

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Number of children with ASD per neighbourhood varies from none to as high as 21.

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Developmental vulnerabilities were not associated with levels of clustering.

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Highest level of clustering of children with ASD was found in Nova Scotia.

"In Medical School, You Get Far More Training on Medical Stuff than Developmental Stuff": Perspectives on ASD from Ontario Physicians

This study investigated the knowledge and perceived competence of Ontario physicians regarding the diagnosis and treatment of ASDs. Previous research demonstrates that many physicians would like more education regarding diagnosis and treatment of autism spectrum disorders (ASDs). Twenty-seven Ontario physicians filled out a questionnaire and participated in a semi-structured interview. Findings revealed that despite participants' high perceived knowledge regarding diagnosis and treatment of ASDs, they feel uncomfortable in providing care for this population. Furthermore, many participants stated diagnosing and treating ASDs is not within their scope of practice. Findings have implications for increasing physicians' knowledge of diagnosis and treatment of ASDs as well as what is required to enhance healthcare for individuals with ASDs and their families.

Impact of changes in human reproduction on the incidence of endocrine-related diseases

The incidence rates of a wide range of diseases and conditions have increased over the last decades. There is controversy over the origin of these increases, whether they are caused by exposure to compounds thought to have an effect on the endocrine system, the "endocrine disruption theory", or whether some other factor is responsible. In this analysis, the authors take a closer look at the role that changes in reproductive factors have played in this respect. They apply the relative risks of age at first pregnancy and parity or family size to a set of Dutch demographic data from 1955 and 2015 and calculate the percentage of disease increase explained. The decrease in parity over the last decades explains an increase of 26% in testicular cancer. The combination of decrease in parity and increase in maternal age at first pregnancy explains an increase of 34% in hypospadias prevalence. This combination of decreased parity and increased maternal age at pregnancy explains an increase of 24% in childhood obesity prevalence. The authors further point to a perhaps even more profound effect of the trend toward smaller families. This trend has led to an estimated doubling of the proportion of children born from subfertile couples. Since children born from subfertile couples are more likely to be preterm or of low birth weight, the incidence of these conditions must have increased as well. Low birth weight and preterm delivery are risk factors for a wide range of diseases and conditions. The changes in human reproduction over the last decades have had a profound impact on the incidence of a range of diseases and conditions in the next generation and thus provide a sound explanation for a substantial portion of the reported increases. Key messages The incidence rates of a wide range of diseases and conditions have increased in the Western societies over the last decades. Many have argued that these increases are attributable to compounds thought to have effects on the human endocrine system: the endocrine disruption theory This analysis shows, however, that human reproductive factors such as maternal age at first pregnancy and parity explain substantial proportions of the reported increases.

Maternal Pre-pregnancy Body Mass Index and Gestational Weight Gain in Relation to Autism Spectrum Disorder and other Developmental Disorders in Offspring

Most prior studies examining maternal pre-pregnancy body mass index (BMI) in relation to offspring autism spectrum disorders (ASD) have reported an association, though findings are not uniform and few have also examined gestational weight gain (GWG). Therefore, we examined both in the Study to Explore Early Development, a multi-site case-control study of children born in 2003-2006. Children identified from clinics, schools, and birth certificates were enrolled at ages 2-5 year and using standardized developmental evaluations, classified as: ASD, other developmental delays (DD), or population-based controls. Maternal height, weight, and GWG were self-reported during the telephone interview. Three primary weight risk factors were examined: (a) Pre-pregnancy BMI, classified as underweight to obese, (b) GWG continuous and categorized as quintiles, and (c) Institute of Medicine clinical weight-gain recommendations. Odds ratios adjusted (AOR) for sociodemographic and prenatal factors were calculated among term singletons, comparing the ASD (n = 540) or DD (n = 720) groups to the control group (n = 776). The AOR of ASD and maternal obesity was 1.37 (95%CI 0.98-1.92). Associations with higher GWG were stronger (Quintile5 vs. Quintile3 AOR = 1.58, 95%CI 1.08-2.31), and particularly so among overweight/obese women (AOR = 1.90, 95%CI 0.98-3.68). DD was associated with maternal overweight and obesity (obesity AOR = 1.48, 95%CI 1.08-2.02), but not with total GWG or clinical recommendations. High maternal BMI and GWG are risk factors for other pregnancy and child outcomes, and our results suggest they may also represent modifiable risk factors for neurodevelopmental outcomes. Autism Res 2019, 12: 316-327 © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: In a large, national study, we found that children with autism were more likely than unaffected children to have mothers with higher weight gain during pregnancy; risk of autism may be even stronger if mothers were also overweight before pregnancy. Children with other developmental delays were more likely to have mothers who were overweight or obese before pregnancy, but not who gained more weight during pregnancy. Overweight and weight gain may represent factors that could be modified.

Measurement considerations in pediatric research on autism spectrum disorders

Studying Autism Spectrum Disorders (ASD) in genetic syndromes has gained interest in the scientific community as a way to elucidate mechanisms and symptom profiles to understand ASD more broadly. Appropriate and adequate measurement of constructs, symptomatology, and outcomes in clinical research is of vital importance in establishing the prevalence of such symptoms and measuring change in symptoms in the context of clinical trials. As such, we provide an overview of the prevalence of ASD, present current diagnostic guidelines, discuss important comorbidities to consider, describe current assessment strategies in assessing ASD, and discuss these within the context of a specific genetic condition to highlight how ASD can be best evaluated.

Family perceptions of the impacts of a home and community based services autism waiver: Making family life possible

BACKGROUND

An important mechanism that provides support and services for families with a child/youth with autism spectrum disorder is the home- and community-based services (HCBS) Waiver authorized by Section 1915(c) of the Social Security Act or Medicaid.

METHODS

This study used qualitative research methods to explore parent perspectives about the impact of HCBS Waiver services on the child/youth with autism and their family. In-depth interviews focused on aspects of the programme they valued, identification of barriers and general issues they experienced.

RESULTS

Results of the qualitative study indicated that improved outcomes could be explained by providers of services who were well-trained, flexible and allowed parents' opportunities for choice regarding provision of services to meet child/youth and family needs.

CONCLUSION

The findings of this study provide guideposts for further research about factors that contribute to satisfaction of families receiving waiver services for quality of life and child progress.

Behavior profiles of children with autism spectrum disorder in kindergarten: Comparison with other developmental disabilities and typically developing children

Monitoring behavior patterns that may be specific to autism spectrum disorder (ASD) at a population level has the potential to improve the allocation of intervention strategies and reduction of the burden of the disease. In Ontario, Canada, developmental data are regularly collected for all kindergarten children with the Early Development Instrument (EDI), a teacher-completed questionnaire that provides information on children's status in five domains: physical, social, emotional, language/cognitive, and communication/general knowledge. Our main research questions are: (a) are there differences in kindergarten EDI domain scores between children who are diagnosed with ASD by Grade 3 and those who develop typically or have other disabilities?; (b) do these differences show a different pattern in relation to an early (by kindergarten) or late (by Grade 3) diagnosis?; and (c) are there specific subdomains on the EDI that demonstrate a consistent pattern of differences? EDI domain and subdomain scores were compared among groups using multivariate analysis of variance controlling for age, gender, EDI year, and EDI year by age interaction. Children with ASD, regardless of timing of identification, had significantly lower scores on all domains of the EDI than typically developing children. Children with later ASD diagnosis had higher scores in kindergarten in cognitive areas but lower scores in social-emotional areas than children with other disabilities. These findings support the potential of the EDI to monitor ASD-like behaviors at the population level. Autism Res 2018, 11: 410-420. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

Identifying behavior patterns among kindergarten children that may be specific to autism spectrum disorder (ASD) at a population level has the potential to improve intervention strategies and thus reduce the burden of the disease. In Ontario, Canada, developmental data are regularly collected with the Early Development Instrument (EDI) for all kindergarten children. The behavior in kindergarten of a sub-population of children diagnosed with developmental disabilities by age 9 is investigated here for patterns that may distinguish children with ASD from those with other disorders. Children with later ASD diagnosis had higher scores in kindergarten in cognitive areas but lower scores in social-emotional areas than children with other disabilities, indicating meaningful differences between those groups even before diagnosis. These results support the potential of using the EDI to monitor ASD-like behaviors at the population level.

Brief Report: Prevalence of Self-injurious Behaviors among Children with Autism Spectrum Disorder-A Population-Based Study

Self-injurious behaviors (SIB) have been reported in more than 30 % of children with an autism spectrum disorder (ASD) in clinic-based studies. This study estimated the prevalence of SIB in a large population-based sample of children with ASD in the United States. A total of 8065 children who met the surveillance case definition for ASD in the Autism and Developmental Disabilities Monitoring (ADDM) Network during the 2000, 2006, and 2008 surveillance years were included. The presence of SIB was reported from available health and/or educational records by an expert clinician in ADDM Network. SIB prevalence averaged 27.7 % across all sites and surveillance years, with some variation between sites. Clinicians should inquire about SIB during assessments of children with ASD.

DSM Criteria that Best Differentiate Intellectual Disability from Autism Spectrum Disorder

Clinical characteristics of autism spectrum disorder (ASD) and intellectual disability (ID) overlap, creating potential for diagnostic confusion. Diagnostic and statistical manual of mental disorders (DSM) criteria that best differentiate children with ID and some ASD features from those with comorbid ID and ASD were identified. Records-based surveillance of ASD among 8-year-old children across 14 US populations ascertained 2816 children with ID, with or without ASD. Area under the curve (AUC) was conducted to determine discriminatory power of DSM criteria. AUC analyses indicated that restricted interests or repetitive behaviors best differentiated between the two groups. A subset of 6 criteria focused on social interactions and stereotyped behaviors was most effective at differentiating the two groups (AUC of 0.923), while communication-related criteria were least discriminatory. Matching children with appropriate treatments requires differentiation between ID and ASD. Shifting to DSM-5 may improve differentiation with decreased emphasis on language-related behaviors.

Contribution of maternal hypertension to autism etiology in a murine model; cerebellar gene expression

Aim: To study the contribution of maternal hypertension to autism spectrum disorders’ (ASD) phenotype, and gene expression, in a murine model. Materials & methods: To examine the effects of maternal hypertension, we used a well-described transgenic mouse model lacking functional endothelial nitric oxide synthase (eNOS or NOS3). Behavioral testing was performed on male offspring between 8 and 10 weeks of age. Cerebella underwent shotgun transcriptome RNA sequencing. Differentially expressed genes were examined for Gene Ontology enrichment. 2-way-RM-ANOVA, 1-way-ANOVA and Student's t-test were used for statistical analysis. Results & conclusion: Our findings revealed that a deficit in social behavior, the hallmark of ASD, is differentially present in offspring born to hypertensive mothers. Novel ASD-related genes were differentially expressed in the cerebellum, implicating its possible role in ASD etiology. Condensation: Altered uterine environment resulting from maternal hypertension contributes to ASD phenotype, and modifies expression of novel ASD-related genes in cerebella of eNOS heterozygous offspring.

[Internal consistency and criterion validity and reliability of the Mexican Version of the Child Behavior Checklist 1.5-5 (CBCL/1.5-5)]

OBJECTIVE

To investigate the validity and internal consistency of the Mexican version of the CBCL/1.5 -5 that assesses the most common psychopathology in pre-school children in clinical and epidemiological settings.

PATIENTS AND METHOD

A total of 438 parents from two groups, clinical-psychiatric (N= 62) and community (N= 376) completed the CBCL/1.5-5/Mexican version.

RESULTS

The internal consistency was high for total problems α=0.95, and internalized α=0.89 and externalized α=0.91 subscales. The test re-test (one week) using the intraclass correlation coefficient (ICC) was ≥ 0.95 for the internalized, externalized, and total problems subscales. The ROC curve for the criterion status of clinically-referred vs. non-referred using the total problems scale ≥ 24 resulted in an AUC (area under curve) of 0.77, a specificity 0.73, and a sensitivity of 0.70.

CONCLUSIONS

The CBCL/1.5 -5/Mexican version is a reliable and valid tool.

Examination of the Korean Modified Checklist of Autism in Toddlers: Item Response Theory

The study examined the clinical utility and psychometric properties of the Korean Modified Checklist of Autism in Toddlers (K-M-CHAT)-2. A sample of 2300 parents of 16- to 36-month-old children was recruited across South Korea. A phone interview was utilized to follow up with participants who initially screened positive for autism spectrum disorder (ASD). Item response theory was applied to assess the psychometric properties of the K-M-CHAT-2. Parents' responses were substantially changed after the follow-up, and the final screen-positive rate was 2.3 %. Results indicated that the psychometric properties of items 1, 3, 11, 18 and 22 were not as strong as the other items. The K-M-CHAT-2 is a useful ASD screening test when implemented with a follow-up.

Brief report: independent validation of autism spectrum disorder case status in the Utah Autism and Developmental Disabilities Monitoring (ADDM) Network Site

An independent validation was conducted of the Utah Autism and Developmental Disabilities Monitoring Network's (UT-ADDM) classification of children with autism spectrum disorder (ASD). UT-ADDM final case status (n = 90) was compared with final case status as determined by independent external expert reviewers (EERs). Inter-rater reliability (ICC = 0.84), specificity [0.83 (95 % CI 0.74-0.90)], and sensitivity [0.99 (95 % CI 0.96-1.00)] were high for ASD case versus non-case classification between UT-ADDM and EER. At least one EER disagreed with UT-ADDM on ASD final case status on nine out of 30 records; however, all three EERs disagreed with UT-ADDM for only one record. Findings based on limited data suggest that children with ASD as identified by UT-ADDM are consistently classified as ASD cases by independent autism experts.

Rates and predictors of adherence to psychotropic medications in children with autism spectrum disorders

Medication adherence in children is poor, particularly among those with chronic or mental health disorders. However, adherence has not been fully assessed in autism spectrum disorders (ASDs). The validated proportion of days covered method was used to quantify adherence to psychotropic medication in Medicaid-eligible children who met diagnostic criteria for ASD between 2000 and 2008 (N = 628). Among children prescribed attention deficit hyperactivity disorder (ADHD) medications, antidepressants, or antipsychotics, 44, 40 and 52 % were adherent respectively. Aggressive behaviors and abnormalities in eating, drinking, and/or sleeping, co-occurring ADHD, and the Medication Regimen Complexity Index were the most significant predictors of adherence rather than demographics or core deficits of ASD. Identifying barriers to adherence in ASD may ultimately lead to improved treatment outcomes.

Sex differences in co-occurring conditions of children with autism spectrum disorders

This study investigated differences in co-occurring diagnoses made in females compared to males with autism spectrum disorders in 913 children (746 males and 167 females) living in the United States with a current autism spectrum disorder diagnosis identified via caregiver-reported data from the National Survey of Children's Health 2007. The results indicated that overall, females had significantly fewer reported autism spectrum disorder co-occurring conditions than males. Females, compared to males, with a current autism spectrum disorder diagnosis had lower rates of past learning disorder, current mild learning disorder, and past anxiety diagnoses. Females with a current autism spectrum disorder diagnosis were more likely than males to have been diagnosed with a speech problem in the past, while males with a current autism spectrum disorder diagnosis were more likely than females to have a current diagnosis of a mild learning disability and a past diagnosis of learning disability. In addition, males with a current autism spectrum disorder diagnosis were more likely than females to have two or more co-occurring diagnoses. These findings provide insight into trends in sex differences in autism spectrum disorder co-occurring conditions.

Childhood vision impairment, hearing loss and co-occurring autism spectrum disorder

BACKGROUND

Limited population-based data on prevalence of childhood vision impairment (VI) and hearing loss (HL), and their co-occurrence with autism spectrum disorder (ASD) exists.

OBJECTIVE

To examine prevalence and characteristics of VI, HL and co-occurring ASD among 8-year-olds in metropolitan Atlanta 2000-2008.

METHODS

We used data from the population-based Metropolitan Atlanta Developmental Disabilities Surveillance Program. Prevalence, birth and parental characteristics, presence and severity of other co-occurring developmental disabilities, and age of earliest identification of ASD, were examined for children with VI and HL, by co-occurring ASD.

RESULTS

VI and HL prevalences were 1.2 and 1.3 per 1000 8-year-olds, respectively. Approximately 6-7% of children with VI or HL had co-occurring ASD. Children with VI or HL with co-occurring ASD differed from those without co-occurring ASD by select birth characteristics and the presence of other co-occurring DDs. The median age of earliest known ASD diagnosis was significantly later among children with VI and ASD compared to children with ASD without VI (79 vs. 56 months). Children with HL and ASD were first evaluated by a community provider significantly earlier than those with ASD without HL (40 vs. 50 months).

CONCLUSIONS

The frequency of co-occurring ASD with VI and HL is higher than the population prevalence of ASD. The significant delays in diagnosis of ASD in children with VI and lack of earlier diagnosis of ASD among children with HL despite earlier evaluation highlight the importance of developing screening tools for early identification of ASD among children with VI and HL.

Translational animal models of autism and neurodevelopmental disorders

Autism is a neurodevelopmental disorder whose diagnosis is based on three behavioral criteria: unusual reciprocal social interactions, deficits in communication, and stereotyped repetitive behaviors with restricted interests. A large number of de novo single gene mutations and chromosomal deletions are associated with autism spectrum disorders. Based on the strong genetic evidence, mice with targeted mutations in homologous genes have been generated as translational research tools. Mouse models of autism have revealed behavioral and biological outcomes of mutations in risk genes. The field is now poised to employ the most robust phenotypes in the most replicable mouse models for preclinical screening of novel therapeutics.

Prenatal and perinatal analgesic exposure and autism: an ecological link

BACKGROUND

Autism and Autism Spectrum Disorder (ASD) are complex neurodevelopmental disorders. Susceptibility is believed to be the interaction of genetic heritability and environmental factors. The synchronous rises in autism/ASD prevalence and paracetamol (acetaminophen) use, as well as biologic plausibility have led to the hypothesis that paracetamol exposure may increase autism/ASD risk.

METHODS

To explore the relationship of antenatal paracetamol exposure to ASD, population weighted average autism prevalence rates and paracetamol usage rates were compared. To explore the relationship of early neonatal paracetamol exposure to autism/ASD, population weighted average male autism prevalence rates for all available countries and U.S. states were compared to male circumcision rates - a procedure for which paracetamol has been widely prescribed since the mid-1990s. Prevalence studies were extracted from the U.S. Centers for Disease Control and Prevention Summary of Autism/ASD Prevalence Studies database. Maternal paracetamol usage and circumcision rates were identified by searches on Pub Med.

RESULTS

Using all available country-level data (n = 8) for the period 1984 to 2005, prenatal use of paracetamol was correlated with autism/ASD prevalence (r = 0.80). For studies including boys born after 1995, there was a strong correlation between country-level (n = 9) autism/ASD prevalence in males and a country's circumcision rate (r = 0.98). A very similar pattern was seen among U.S. states and when comparing the 3 main racial/ethnic groups in the U.S. The country-level correlation between autism/ASD prevalence in males and paracetamol was considerably weaker before 1995 when the drug became widely used during circumcision.

CONCLUSIONS

This ecological analysis identified country-level correlations between indicators of prenatal and perinatal paracetamol exposure and autism/ASD. State level correlation was also identified for the indicator of perinatal paracetamol exposure and autism/ASD. Like all ecological analyses, these data cannot provide strong evidence of causality. However, biologic plausibility is provided by a growing body of experimental and clinical evidence linking paracetamol metabolism to pathways shown to be important in autism and related developmental abnormalities. Taken together, these ecological findings and mechanistic evidence suggest the need for formal study of the role of paracetamol in autism.

Evaluating Changes in the Prevalence of the Autism Spectrum Disorders (ASDs)

Autism spectrum disorders (ASDs) are estimated to occur among about one percent of children in the United States. This estimate is in line with estimates from other industrialized countries. However, the identified prevalence of ASDs has increased significantly in a short time period based on data from multiple studies including the U.S. Centers for Disease Control and Prevention's (CDC) Autism and Developmental Disabilities Monitoring (ADDM) Network. Whether increases in ASD prevalence are partly attributable to a true increase in the risk of developing ASD or solely to changes in community awareness and identification patterns is not known. It is clear that more children are identified with an ASD now than in the past and the impact on individuals, families, and communities is significant. However, disentangling the many potential reasons for ASD prevalence increases has been challenging. Understanding the relative contribution of multiple factors such as variation in study methods, changes in diagnostic and community identification, and potential changes in risk factors is an important priority for the ADDM Network and for CDC. This article summarizes the discussion from a workshop that was co-sponsored by CDC and Autism Speaks as a forum for sharing knowledge and opinions of a diverse range of stakeholders about changes in ASD prevalence. Panelists discussed recommendations for building on existing infrastructure and developing new initiatives to better understand ASD trends. The information, research, and opinions shared during this workshop add to the knowledge base about ASD prevalence in an effort to stimulate further work to understand the multiple reasons behind increasing ASD prevalence.

An ecological study on childhood autism

BACKGROUND AND METHODS

Idiopathic autism, suspected to be caused by exposure of genetically susceptible individuals to unknown environmental triggers, has increased dramatically in the past 25 years. The objectives of our study were to determine, using a linear regression model, whether the county prevalence of autism in the Pacific Northwest of the United States was associated with the source of drinking water for that county and whether this relationship was dependent on the level of environmental pollutants and meteorological factors in the county.

RESULTS

We found the previously reported relationship between precipitation and autism in a county was dependent on the amount of drinking water derived from surface sources in the county. We also found a positive association between the EPA's risk of neurological disease and autism, but this relationship was only present in warm areas.

CONCLUSIONS

Our study provides evidence for the hypothesis that environmental factors are associated with autism and that meteorological factors play a role in this relationship.

Ultrasound and autism: association, link, or coincidence?

Autism spectrum disorders (ASDs) affect an estimated 1% of children in the United States. The etiology is probably multifactorial, including genetic components and exposure to infections, toxins, and other environmental factors, particularly unfavorable perinatal and neonatal conditions. There has been an increase in the frequency of diagnosis of ASDs over the last 20 years with a parallel increase in the use of obstetric diagnostic ultrasound, with prenatal ultrasound exposure mentioned as the possible main etiology for autism "epidemics." Central nervous system alterations have been described in ASDs, and certain similar changes have been described in animals after exposure to ultrasound. However, analysis of in utero exposure in humans has failed to show harmful effects in neonates or children, particularly in school performance, attention disorders, and behavioral changes. There is no independently confirmed peer-reviewed published evidence that a cause-effect relationship exists between in utero exposure to clinical ultrasound and development of ASDs in childhood. Ultrasound is a form of energy with effects in the tissues it traverses, and its use should be restricted to medical indications, by trained professionals, for as short a period and as low an intensity as compatible with accurate diagnosis.

The First Year Inventory: a longitudinal follow-up of 12-month-old to 3-year-old children

The First Year Inventory is a parent-report measure designed to identify 12-month-old infants at risk for autism spectrum disorder. First Year Inventory taps behaviors that indicate risk in the developmental domains of sensory-regulatory and social-communication functioning. This longitudinal study is a follow-up of 699 children at 3 years of age from a community sample whose parents completed the First Year Inventory when their children were 12 months old. Parents of all 699 children completed the Social Responsiveness Scale-Preschool version and the Developmental Concerns Questionnaire to determine age 3 developmental outcomes. In addition, children deemed at risk for autism spectrum disorder based on liberal cut points on the First Year Inventory, Social Responsiveness Scale-Preschool, and/or Developmental Concerns Questionnaire were invited for in-person diagnostic evaluations. We found 9 children who had a confirmed diagnosis of autism spectrum disorder from the sample of 699. Receiver operating characteristic analyses determined that a two-domain cutoff score yielded optimal classification of children: 31% of those meeting algorithm cutoffs had autism spectrum disorder and 85% had a developmental disability or concern by age 3. These results suggest that the First Year Inventory is a promising tool for identifying 12-month-old infants who are at risk for an eventual diagnosis of autism spectrum disorder.

Completeness of case ascertainment for surveillance of autism spectrum disorders using the autism developmental disabilities monitoring network methodology

BACKGROUND

The Autism and Developmental Disabilities Monitoring Network (ADDM), sponsored by the Centers for Disease Control and Prevention, is the largest-scale project ever undertaken to identify the prevalence of Autism Spectrum Disorders (ASD) in the United States.

OBJECTIVE

The objective of the present study was to examine the accuracy of the ADDM methodology in terms of completeness of case ascertainment; that is, to assess the success of the ADDM Network in identifying and accurately classifying all existing cases of ASD among 8-year-old children in the target study areas.

METHODS

To accomplish this objective, the ADDM methodology was applied to a selected region of South Carolina for 8-year olds in 2000 (birth year 1992) and again seven years later for the same region and birth year.

RESULTS

For this region and birth year, completeness of case ascertainment was high, with prevalence estimates of 7.6 per 1000 at both ages 8- and 15-years. For children common to both surveillance years, concordance in case status was also high (82%).

CONCLUSIONS

Given that prevalence did not change within this region and birth year, continued research is needed to better understand the changes in prevalence estimates being found by the ADDM network across surveillance groups.

M-CHAT Mexican Version Validity and Reliability and Some Cultural Considerations

The Modified Checklist for Autism in Toddlers (M-CHAT) questionnaire is a brief measure available in Spanish which needs to be validated for the Mexican population. Parents of children from (1) community with typical development (TD) and (2) psychiatric outpatient unit completed the CBCL/1.5–5 and the Mexican/MM-CHAT-version. The study sample consisted of 456 children (age M = 4.46, SD = 1.12), 74.34% TD children and 26.65% with Autism Spectrum Disorders (ASD). The MM-CHAT mean score for failed key items was higher for the ASD group compared with the TD group. Internal consistency for the Mexican/M-CHAT version was .76 for total score and .70 for the 6 critical items. Correlations between the MM-CHAT and the CBCL/1.5: PDD and Withdrawn subscales and with ADI-R dimensions: B non verbal) and A were high, and were moderate with ADI-R dimensions B1 (verbal) and C The failure rate of the MM-CHAT between the groups did not reproduce all the critical items found in other studies. Although the instrument has good psychometric properties and can be used for screening purposes in primary settings or busy specialized psychiatric clinics, these results support evidence for cultural differences in item responses, making it difficult to compare M-CHAT results internationally.

Lack of evidence for neonatal misoprostol neurodevelopmental toxicity in C57BL6/J mice

Misoprostol is a synthetic analogue of prostaglandin E1 that is administered to women at high doses to induce uterine contractions for early pregnancy termination and at low doses to aid in cervical priming during labor. Because of the known teratogenic effects of misoprostol when given during gestation and its effects on axonal growth in vitro, we examined misoprostol for its potential as a neurodevelopmental toxicant when administered to neonatal C57BL6/J mice. Mice were injected subcutaneously (s.c.) with 0.4, 4 or 40 µg/kg misoprostol on postnatal day 7, the approximate developmental stage in mice of human birth, after which neonatal somatic growth, and sensory and motor system development were assessed. These doses were selected to span the range of human exposure used to induce labor. In addition, adult mice underwent a battery of behavioral tests relevant to neurodevelopmental disorders such as autism including tests for anxiety, stereotyped behaviors, social communication and interactions, and learning and memory. No significant effects of exposure were found for any measure of development or behavioral endpoints. In conclusion, the results of the present study in C57BL/6J mice do not provide support for neurodevelopmental toxicity after misoprostol administration approximating human doses and timed to coincide with the developmental stage of human birth.

Psychoactive pharmaceuticals induce fish gene expression profiles associated with human idiopathic autism

Idiopathic autism, caused by genetic susceptibility interacting with unknown environmental triggers, has increased dramatically in the past 25 years. Identifying environmental triggers has been difficult due to poorly understood pathophysiology and subjective definitions of autism. The use of antidepressants by pregnant women has been associated with autism. These and other unmetabolized psychoactive pharmaceuticals (UPPs) have also been found in drinking water from surface sources, providing another possible exposure route and raising questions about human health consequences. Here, we examined gene expression patterns of fathead minnows treated with a mixture of three psychoactive pharmaceuticals (fluoxetine, venlafaxine & carbamazepine) in dosages intended to be similar to the highest observed conservative estimates of environmental concentrations. We conducted microarray experiments examining brain tissue of fish exposed to individual pharmaceuticals and a mixture of all three. We used gene-class analysis to test for enrichment of gene sets involved with ten human neurological disorders. Only sets associated with idiopathic autism were unambiguously enriched. We found that UPPs induce autism-like gene expression patterns in fish. Our findings suggest a new potential trigger for idiopathic autism in genetically susceptible individuals involving an overlooked source of environmental contamination.

Prevalence of autism spectrum disorders in Hispanic and non-Hispanic white children

OBJECTIVE

The number of individuals diagnosed with autism spectrum disorders (ASDs) continues to increase in the United States and other developed countries; however, ASD is diagnosed less commonly in Hispanic than in non-Hispanic white individuals. This report analyzes differences in ASD prevalence between Hispanic and non-Hispanic whites in a large, population-based sample of 8-year-old children, and explores how prevalence has changed over time.

METHODS

Population-based surveillance of ASD was conducted on 142 717 8-year-old children. Evaluation of clinical and educational records resulted in 1212 children meeting the case definition criteria in 4 study years between 2000 and 2006.

RESULTS

ASD prevalence in Hispanic children was lower than in non-Hispanic white children (P < .005) for all study years. More Hispanic than non-Hispanic white children met the case definition for intellectual disability (P < .05) in study years 2004 and 2006. Prevalence of ASD diagnosis increased in both groups; the Hispanic prevalence almost tripled, from 2.7 per 1000 in 2000 to 7.9 per 1000 in 2006. A comparison of prevalence ratios found that Hispanic and non-Hispanic white ASD prevalence became significantly more similar from 2000 to 2006 (χ(2) = 124.89, P < .001).

CONCLUSIONS

The ASD prevalence for Hispanic individuals in this population-based sample is substantially higher than previously reported. Nonetheless, Hispanic children continue to have a significantly lower ASD prevalence in comparison with non-Hispanic whites. The prevalence of ASD is increasing in both populations, and results indicate that the gap in prevalence between groups is decreasing.

Cohort effects explain the increase in autism diagnosis among children born from 1992 to 2003 in California

BACKGROUND

The incidence and prevalence of autism have dramatically increased over the last 20 years. Decomposition of autism incidence rates into age, period and cohort effects disentangle underlying domains of causal factors linked to time trends. We estimate an age-period-cohort effect model for autism diagnostic incidence overall and by level of functioning.

METHODS

Data are drawn from sequential cohorts of all 6 501 262 individuals born in California from 1992 to 2003. Autism diagnoses from 1994 to 2005 were ascertained from the California Department of Development Services Client Development and Evaluation Report.

RESULTS

Compared with those born in 1992, each successively younger cohort has significantly higher odds of an autism diagnosis than the previous cohort, controlling for age and period effects. For example, individuals born in 2003 have 16.6 times the odds of an autism diagnosis compared with those born in 1992 [95% confidence interval (CI) 7.8-35.3]. The cohort effect observed in these data is stronger for high than for low-functioning children with an autism diagnosis.

DISCUSSION

Autism incidence in California exhibits a robust and linear positive cohort effect that is stronger among high-functioning children with an autism diagnosis. This finding indicates that the primary drivers of the increases in autism diagnoses must be factors that: (i) have increased linearly year-to-year; (ii) aggregate in birth cohorts; and (iii) are stronger among children with higher levels of functioning.

A proposal to facilitate weight-of-evidence assessments: Harmonization of Neurodevelopmental Environmental Epidemiology Studies (HONEES)

The ability to conduct weight-of-evidence assessments to inform the evaluation of potential environmental neurotoxicants is limited by lack of comparability of study methods, data analysis, and reporting. There is a need to establish consensus guidelines for conducting, analyzing, and reporting neurodevelopmental environmental epidemiologic studies, while recognizing that consistency is likewise needed for epidemiology studies examining other health outcomes. This paper proposes a set of considerations to be used by the scientific community at-large as a tool for systematically evaluating the quality of proposed and/or published studies in terms of their value for weight-of-evidence assessments. Particular emphasis is placed on evaluating factors influencing the risk of incorrect conclusions at the level of study findings. The proposed considerations are the first step in what must be a larger consensus-based process and can serve to catalyze such a discussion. Achieving consensus in these types of endeavors is difficult; however, opportunities exist for further interdisciplinary discussion, collaboration, and research that will help realize this goal. Broad acceptance and application of such an approach can facilitate the expanded use of environmental epidemiology studies of potential neurodevelopmental toxicants in the protection of public health, and specifically children's health.

Trends in the prevalence of autism on the basis of special education data

OBJECTIVE

The goal was to determine whether the increasing prevalence of autism, on the basis of educational data, in Wisconsin between 2002 and 2008 was uniform in all school districts or was greatest in districts with lower baseline (2002) prevalence.

METHODS

Special education counts were obtained for all Wisconsin elementary school districts from 2002 through 2008. The annual prevalence of children being served under the autism category was calculated for each district, districts were grouped into 8 categories (octiles) according to their baseline prevalence, and prevalence trends were plotted according to octile.

RESULTS

The overall prevalence of use of the autism category in Wisconsin elementary schools increased from 4.9 to 9.0 cases per 1000 children between 2002 and 2008. The magnitude of this increase was not uniform across districts and was inversely associated with baseline prevalence. Prevalence in the lowest octile increased from 0.5 cases per 1000 students in 2002 to 7.0 cases per 1000 students in 2008 (P < .0001), whereas no significant trend was seen for the octile with the highest baseline prevalence (range: 11.2-12.3 cases per 1000 students; P = .11). The highest-octile/lowest-octile prevalence ratio decreased from 24.6 (95% confidence interval: 16.2-37.3) in 2002 to 1.8 (95% confidence interval: 1.6-2.1) in 2008.

CONCLUSIONS

The prevalence of use of the autism special education category in Wisconsin seems to be leveling off in the school districts with the highest prevalence rates, at ∼12 cases per 1000 students, whereas the gap in prevalence between districts overall has narrowed.