Prevalence of autism spectrum disorders in an Icelandic birth cohort

Prevalence of Autism in Scandinavian Countries (Denmark, Norway, Sweden), and Nordic Countries (Finland, Iceland, the Faroe Islands, and Greenland)

Aim

This study aims to identify and describe prevalence rates for ASD in the Scandinavian countries (Denmark, Norway, Sweden), as well as the Nordic countries (Finland, Iceland, the Faroe Islands, and Greenland).

Methods

A systematic review was conducted following PRISMA (2009) guidelines and based on the two databases: APA PsycINFO and MEDLINE (PubMed).

Results

A total of 13 studies were included in the analyses. It was not possible to identify ASD prevalence studies for Greenland. However, for the remaining countries descriptive increases in ASD prevalence figures were observed. Increases were evident both in relation to age and birth cohort. Studies varied regarding which age group and cohort prevalence figures were reported. The most reported age group was the 7-12-year-olds. In this group, recent prevalence figures for Denmark ranged from 0.26% to 1.47%, in Norway 0.6%, in Sweden 0.23-0.68%, in Finland 0.22-0.86%, and in Iceland 2.40-3.13%. Iceland stood out in terms of higher prevalence figures compared to the other Scandinavian and Nordic countries. Two studies from the Faroe Islands reported ASD prevalence rates between 0.50% and 0.94% for 7-24-year-olds. These studies were based on nationwide figures, but not from national or official registers.

Discussion and conclusion

This study documented increasing prevalence of ASD in Scandinavian and Nordic countries. Several explanations of aspects that may contribute to the increases were discussed, eg, heightened awareness of ASD and earlier diagnosis. The importance of considering differences in data sources was discussed, with an emphasis on the importance of using national registries when available as this source is the most reliable and valid. The absence of prevalence figures for Greenland may be attributed to structural as well as cultural aspects, eg, two parallel systems assessing ASD, cultural taboos as well as lack of awareness of ASD. Suggestions or how to gain knowledge on ASD prevalence in Greenland is presented.

Melatonin improves synapse development by PI3K/Akt signaling in a mouse model of autism spectrum disorder

JOURNAL/nrgr/04.03/01300535-202407000-00043/figure1/v/2023-11-20T171125Z/r/image-tiff

Autism spectrum disorders are a group of neurodevelopmental disorders involving more than 1100 genes, including Ctnnd2 as a candidate gene. Ctnnd2 knockout mice, serving as an animal model of autism, have been demonstrated to exhibit decreased density of dendritic spines. The role of melatonin, as a neurohormone capable of effectively alleviating social interaction deficits and regulating the development of dendritic spines, in Ctnnd2 deletion-induced nerve injury remains unclear. In the present study, we discovered that the deletion of exon 2 of the Ctnnd2 gene was linked to social interaction deficits, spine loss, impaired inhibitory neurons, and suppressed phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signal pathway in the prefrontal cortex. Our findings demonstrated that the long-term oral administration of melatonin for 28 days effectively alleviated the aforementioned abnormalities in Ctnnd2 gene-knockout mice. Furthermore, the administration of melatonin in the prefrontal cortex was found to improve synaptic function and activate the PI3K/Akt signal pathway in this region. The pharmacological blockade of the PI3K/Akt signal pathway with a PI3K/Akt inhibitor, wortmannin, and melatonin receptor antagonists, luzindole and 4-phenyl-2-propionamidotetralin, prevented the melatonin-induced enhancement of GABAergic synaptic function. These findings suggest that melatonin treatment can ameliorate GABAergic synaptic function by activating the PI3K/Akt signal pathway, which may contribute to the improvement of dendritic spine abnormalities in autism spectrum disorders.

Prevalence of autism spectrum disorder among children in Southeast Asia from 2002 to 2022: An updated systematic review and meta-analysis

Background and Aims

Autism spectrum disorder (ASD) is a neurodevelopmental condition that impacts the brain, characterized by challenges in social communication and interaction, often accompanied by repetitive behaviors or focused interests. This study sheds light on the prevalence of ASD within the Southeast Asian region.

Methods

The study protocol was registered in PROSPERO (Registration No: CRD42023413915). Appropriate search terms and Boolean operators were employed to explore electronic databases for relevant articles. Data thus extracted were prepared in Excel and analyzed in Comprehensive Meta-Analysis Software. The effect measure utilized in the study was represented by the proportion, and the choice between a fixed or random-effect model depended on the observed heterogeneity. Visual feedback was provided through the use of forest plots and funnel plots.

Results

A total of 14 studies were included in the qualitative and quantitative synthesis after screening the imported studies. The prevalence of ASD was six per 1000 population (proportion: 0.006; CI: 0.002-0.017; I 2: 99.263%). Among the ASD cases, 64.4% (proportion: 0.644; CI: 0.590-0.693; I 2: 9.937%) were males and 35.6% (proportion: 0.356; CI: 0.307-0.410; I 2: 9.937%) were females.

Conclusion

The prevalence of ASD in Southeast Asia was estimated to be six cases per 1000 individuals, with a higher prevalence among males. This study contributes to our understanding of ASD prevalence in the region, although it is essential to note certain limitations in estimating prevalence.

Autism care pathway in Europe

BACKGROUND

Autism is a lifelong complex neurodevelopmental condition that affects brain development and behaviour with significant consequences for everyday life. Despite its personal, familial, and societal impact, Europe-wide harmonised guidelines are still lacking for early detection, diagnosis, and intervention, leading to an overall unsatisfactory autistic person and carer journey.

METHODS

The care pathway for autistic children and adolescents was analysed in Italy, Spain and the UK from the perspective of carers (using a survey aimed at caregivers of autistic children 0-18 years old), the autistic community, and professionals in order to identify major barriers (treatment gaps) preventing carers from receiving information, support, and timely screening/diagnosis and intervention.

RESULTS

Across all three countries, analysis of the current care pathway showed: long waits from the time carers raised their first concerns about a child's development and/or behaviour until screening and confirmed diagnosis; delayed or no access to intervention once a diagnosis was confirmed; limited information about autism and how to access early detection services; and deficient support for families throughout the journey.

CONCLUSIONS

These findings call for policy harmonisation in Europe to shorten long wait times for diagnosis and intervention and therefore, improve autistic people and their families' journey experience and quality of life.

Prevalence of Autism Spectrum Disorder in the Centro region of Portugal: a population based study of school age children within the ASDEU project

Introduction

Accurate prevalence estimates for Autism Spectrum Disorder (ASD) are fundamental to adequately program medical and educational resources for children. However, estimates vary globally and across Europe, and it is therefore wise to conduct epidemiological studies in defined geo-cultural contexts.

Methods

We used a population screening approach to estimate the prevalence of ASD in the Centro region of Portugal, using a harmonized protocol as part of the Autism Spectrum Disorders in the European Union (ASDEU) project.

Results

The overall prevalence was estimated at 0.5% (95% CI 0.3-0.7), higher in schools with Autism Units (3.3%, 95%CI 2.7-3.9) than in regular schools (0.3%, 95% CI 0.1-0.5) or schools with Multiple Disability Units (0.3%, 95% CI 0.04-0.6).

Discussion

The results indicate that the diagnosis of ASD is followed by the most effective educational policies in Centro Region. The variability in prevalence estimates across the different regions from the ASDEU project, and globally, is discussed.

Identification of autism in cognitively able adults with epilepsy: A narrative review and discussion of available screening and diagnostic tools

The recent NICE epilepsy Guideline (NG217; 2022) recommends that epilepsy professionals need to be alert to autism when considering mental health presentations, behavioural difficulties and as a marker for referral for whole genome sequencing for those patients with epilepsy of unknown cause. However, this relies upon the existence of valid autism screens for people with epilepsy (PWE). We found few studies of autism in cognitively able PWE. This represents an important gap in the literature. We describe different autism screening and diagnostic tools; two screening tools have been used specifically for adult PWE who are cognitively able (AQ, SRS-AS). The AQ is more psychometrically robust, but there may be an overlap between these screening questions and questions relevant to some psychiatric disorders. Formal gold-standard diagnostic tools (module 4 of ADOS-2, ADI-R or 3Di or 3Di-Adult) would benefit from studies of their application to cognitively able PWE. More research is needed to understand the characteristics of autism in cognitively able PWE and to ascertain the appropriate screening and diagnostic tools for this cohort.

The global prevalence of autism spectrum disorder: A three-level meta-analysis

Autism spectrum disorder (ASD) is one the most disabling developmental disorders, imposing an extremely high economic burden. Obtaining as accurate prevalence estimates as possible is crucial to guide governments in planning policies for identification and intervention for individuals with ASD and their relatives. The precision of prevalence estimates can be heightened by summative analyses of the data collected around the world. To that end, we conducted a three-level mixed-effects meta-analysis. A systematic search of the Web of Science, PubMed, EMBASE, and PsycINFO databases from 2000 up to 13 July 2020 was performed, and reference lists of previous reviews and existing databases of prevalence studies were screened. Overall, 79 studies were included in the analysis of ASD and 59-in the analysis of previously existing relevant diagnoses: 30 for Autistic Disorder (AD), 15 for Asperger Syndrome (AS), and 14 for Atypical Autism (AA) and Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS); these research reports covered the period from 1994 to 2019. Pooled prevalence estimates were 0.72% (95% CI = 0.61-0.85) for ASD, 0.25% (95% CI = 0.18-0.33) for AD, 0.13% (95% CI = 0.07-0.20) for AS, and 0.18% (95% CI = 0.10-0.28) for the combined group of AA and PDD-NOS. Estimates were higher (1) for the studies that used records-review surveillance rather than other designs; (2) in North America compared with other geographical regions; and (3) in high-income compared with lower-income countries. The highest prevalence estimates were registered in the USA. There was an increase in autism prevalence estimates over time. The prevalence was also significantly higher for children aged between 6 and 12 years compared to children under the age of 5 and over the age of 13 years.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42019131525, identifier CRD42019131525.

Smartphone-based behaviour analysis for challenging behaviour in intellectual and developmental disabilities and autism spectrum disorder - Study protocol for the ProVIA trial

Background

Challenging behaviour (CB) comprises various forms of aggressive and problematic behaviours frequently occurring in children with intellectual and developmental disability (IDD) or autism spectrum disorder (ASD). CB often arises from impaired communication or problem solving skills. It is often met with coercive measure due to a lack of alternative strategies on the part of the caregiver, while it also impacts on the caregivers due to the exposure to physical harm and high levels of stress. Within the ProVIA project we developed a smartphone-based tool for caregivers of children with IDD and/or ASD to prevent and modify CB. The ProVIA app systematically helps caregivers to identify specific causes of CB and provides individualised practical guidance to prevent CB and consecutive coercive measures, thus aiming to improve the health and well-being of the children and caregivers.

Methods

In this uncontrolled open trial we will enrol N = 25 caregivers of children aged 3-11 years with a diagnosis of IDD and/or ASD. Participants will use the ProVIA-Kids app for 8 weeks. During the intervention phase, participants will conduct behaviour analyses after each instance of CB. The app will summarise the identified putative causes for the CB in each situation, and provide recommendations regarding the handling and prevention of CB. Furthermore, the app will aggregate data from all available behaviour analyses and identify the most relevant (i.e., most frequently reported) risk factors. Measurement points are at baseline (T0), after the intervention (T1) and 12 weeks after the end of the intervention (follow-up; T2). The primary outcome is the absolute change in parental stress (EBI total scale) between T0 and T1. Further aspects of interest are changes in CB severity and frequency, caregiver mood, satisfaction with the parenting role (EFB-K total scale) and experienced parenting competence (FKE total scale). Pre-post comparisons will be analysed with paired sample t-tests.

Discussion

ProVIA is pioneering structured behaviour analysis via smartphone, assessing predefined causes of CB and providing feedback and recommendations. If this approach proves successful, the ProVIA-Kids app will be a valuable tool for caregivers to prevent CB and improve their own as well as the children's quality of life.

Trial registration

The study is registered at https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_IDDRKS00029039 (registered May 31, 2022).

Attitudes Towards Evidence-Based Practice of Professionals Working with Children and Adolescents with Autism Spectrum Disorder in Bangladesh

Like in many lower-middle-income countries (LMIC), progress in implementing evidence-based practices (EBPs) for children with autism spectrum disorder (ASD) has been slow in Bangladesh. This cross-sectional study examined professionals' attitudes towards evidence-based practice (EBP) for children and adolescents with ASD and explored how providers' demographic factors are related to attitudes to and adoption of EBPs in Bangladesh. The sample consisted of 150 mental health professionals and special teachers from the urban area of Dhaka. Attitudes were assessed by the Evidence-based Practice Attitude Scale-36. Findings indicated that professionals have favorable attitudes towards EBP. Their attitudes varied depending on service settings (public clinical, private clinical, and special school) and caseload per year. Professionals who work in private and special school settings claimed to be more willing to adopt an EBP when required and perceived a higher fit of EBPs and their work than those in public clinical settings. The number of different EBPs used also differed by service setting. Every type of intervention (except medication) was used by more professionals in special schools than in private and public clinical settings. Many professionals reported few barriers to the implementation of EBPs. These findings indicate conditions that are often conducive to the implementation of EBPs. However, these results do not reflect the situation in rural areas, in which poverty is more widespread and the number of specialized professionals is low.

Effectiveness of interventions for children and adolescents with autism spectrum disorder in high-income vs. lower middle-income countries: An overview of systematic reviews and research papers from LMIC

Background

There is a multitude of systematic reviews of interventions for children and adolescents with autism spectrum disorder (ASD). However, most reviews seem to be based on research conducted in High-Income Countries (HIC). Thus, summary findings may not directly apply to Lower Middle-Income Countries (LMIC). Therefore, we conducted a Meta-Review analyzing systematic reviews on the effectiveness of interventions for target outcomes in children and adolescents with ASD to find out whether there are differences in effectiveness between HIC and LMIC and which interventions can be considered evidence-based in LMIC.

Methods

Electronic databases (PsycINFO, PubMed, Cochrane database of systematic reviews) were searched for reviews on interventions for ASD in children and adolescents from January 2011 through December 2021, which included studies not coming from HIC. Systematic reviews with qualitative and quantitative syntheses of findings were included. Two investigators independently assessed studies against predetermined inclusion/exclusion criteria and extracted relevant data including quality and evidence assessments. Evidence for different types of interventions in HIC vs. LMIC was planned to be compared, but none of the reviews assessed potential differences. Therefore, a narrative review of the studies from LMIC was conducted including an assessment of quality and evidence.

Results

Thirty-five reviews fulfilled the inclusion criteria. Eleven considered findings from HIC and LMIC. Sixty-nine percent included studies with various research designs; 63% provided a qualitative synthesis of findings; 77% percent assessed the quality of studies; 43% systematically assessed the level of evidence across studies. No review compared evidence from HIC and LMIC. A review of the studies from LMIC found some promising results, but the evidence was not sufficient due to a small number of studies, sometimes poor quality, and small sample sizes.

Conclusion

Systematic reviews on interventions for children and adolescents with ASD did not look for potential differences in the effectiveness of interventions in HIC and LMIC. Overall, there is very little evidence from LMIC. None of the interventions can be considered evidence-based in LMIC. Hence, additional research and mutually agreed methodological standards are needed to provide a more secure basis for evidence-based treatments in LMIC trying to establish evidence-based practices.

The global prevalence of autism spectrum disorder: a comprehensive systematic review and meta-analysis

Background

Autism spectrum disorder (ASD) is one of the serious developmental disorders that is usually diagnosed below the age of three years. Although the severity of the disease’s symptoms varies from patient to patient, the ability to communicate with others is affected in all forms of ASD. This study aimed to determine the prevalence of ASD in high-risk groups by continent.

Methods

The present study was conducted by systematic review and meta-analysis from 2008 to July 2021. Databases such as Science Direct, PubMed, Scopus, SID, Magiran, Web of Science (WoS), and Google Scholar from 2008 to July 2021 were searched to find related studies. Data were analysed using Comprehensive Meta-Analysis software (Version 2).

Results

A total of 74 studies with 30,212,757 participants were included in this study. The prevalence of ASD in the world was 0.6% (95% confidence interval: 0.4–1%). Subgroup analyses indicated that the prevalence of ASD in Asia, America, Europe, Africa and Australia was 0.4% (95% CI: 0.1–1), 1% (95% CI: 0.8–1.1), 0.5% (95% CI: 0.2–1), 1% (95% CI: 0.3–3.1), 1.7% (95% CI: 0.5–6.1) respectively.

Conclusion

ASD imposes a heavy health burden on communities around the world. Early detection of ASD can reduce the incidence of developmental disorders and improve patients’ communication skills. Therefore, health policymakers need to be aware of the prevalence and increasing trend of ASD to implement appropriate planning and interventions to reduce its consequences.

IQ in Autism Spectrum Disorder: A Population-Based Birth Cohort Study

OBJECTIVES

We aimed to describe the intellectual ability and ratio of boys to girls with average or higher IQ within autism spectrum disorder (ASD) cases identified in a population-based birth cohort. We hypothesized that research-identified individuals with ASD would be more likely to have average or higher IQ, compared to clinically diagnosed ASD. We also hypothesized the male to female ratio would decrease as the definition of ASD broadened.

METHODS

ASD incident cases were identified from 31 220 subjects in a population-based birth cohort. Research-defined autism spectrum disorder, inclusive criteria (ASD-RI) was based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, autistic disorder (AD), Asperger Disorder, and pervasive developmental disorder not otherwise specified criteria. Research-defined autism spectrum disorder, narrow criteria (ASD-RN) was a narrower definition based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision AD criteria. Clinical diagnoses of ASD were abstracted from medical and school records. Intellectual ability was based on the last IQ score or on documented diagnoses of intellectual disability if no scores available. Average or higher IQ was defined as IQ ≥86.

RESULTS

A total of 59.1% of those with ASD-RI (n = 890), 51.2% of those with ASD-RN (n = 453), and 42.8% of those with clinically diagnosed autism spectrum disorder (n = 187) had average or higher IQ. Within the ASD-RI and ASD-RN groups, boys were more likely than girls to have an average or higher IQ (62.0% vs 51.3% [P = .004] and 54.1% vs. 42.5% [P = .03], respectively).

CONCLUSION

Our data suggest that nearly half of individuals with ASD have average or higher IQ. Boys with ASD are more likely to have average or higher IQ than girls. Patients with ASD and higher IQ remain at risk for not being identified.

Prevalence of epilepsy in autism spectrum disorders: A systematic review and meta-analysis

LAY ABSTRACT

Autistic individuals experience higher co-occurring medical conditions than the general population, and yet the estimates of autistic individuals with epilepsy are not updated. Co-occurrence of epilepsy in autistic individuals often aggravated cognitive impairment and increased the risk of poor long-term prognosis. Thus, an updated systematic review and meta-analysis was conducted to study the relevant articles published from inception to 2020, evaluate the prevalence of epilepsy in autistic individuals, and further explore the putative factors influencing the prevalence. A total of 66 studies from 53 articles were included in this study. The results showed that epilepsy is more common in autistic individuals than in the general population. The prevalence of epilepsy in autistic individuals in the clinical sample-based studies was higher than that in the population-based based cross-sectional or cohort studies. The prevalence of epilepsy in autistic adults was higher than that in autistic children. A significantly increased prevalence of epilepsy was detected in the autistic adolescent group (11-17 years old), and a higher trend of prevalence of epilepsy was observed in the autistic pre-school group (⩽ 6 -years-old) than that of the autistic school-aged group (7-10 years-old). The prevalence of epilepsy increased with age, female rate, and low intellectual function rate of autistic individuals. However, the human development index of countries was negatively associated with the pooled prevalence, which could be attributed to the different levels of awareness, diagnostic technologies, and autism-service support worldwide. About 1/10 autistic individuals also had epilepsy, which was common in the clinical setting, adolescents, adults, females, or patients with intellectual disability and less common in the country with high human development index. Thus, these findings provided critical and innovative views on the prevalence of epilepsy in autistic individuals and contributed to the targeted clinical management and preventive measures.

Practical applications of brief screening questionnaires for autism spectrum disorder in a psychiatry outpatient setting

OBJECTIVES

This study was designed to examine the diagnostic performance of the social and communication disorders checklist (SCDC) and strength and difficulties questionnaire (SDQ) to detect autism spectrum conditions (ASC), along with the social responsiveness scale-second edition (SRS-2) as reference, in a psychiatry outpatient setting.

METHODS

We translated the SCDC into Japanese since its Japanese version was unavailable. We examined its test-retest reliability as well as the internal consistency reliability and diagnostic performance of the three questionnaires among 41 Japanese psychiatric outpatients, using the best-estimate diagnosis of ASC based on the diagnostic interview for social and communication disorders, as a gold standard.

RESULTS

The test-retest reliability was high for the SCDC. Although the internal consistency reliability was high for the SCDC and SRS-2, that was low for the prosocial and peer problem subscales of the SDQ. The performance of the SCDC, SDQ, and SRS-2 to detect ASC was moderate: the area under the ROC curve of 0.78, 0.78, and 0.84, respectively.

CONCLUSIONS

Although questionnaires to detect ASC, including the three examined, generally have only moderate performance in this setting, these can be successfully applied to high-risk populations such as psychiatry outpatients, when multi-level rather than dichotomous likelihood ratios are used.

Post-graduate Medical Training in Intellectual and Developmental Disabilities: a Systematic Review

OBJECTIVE

Despite the increasing number of people with autism-spectrum disorder (ASD), intellectual disabilities (ID), and developmental disabilities (DDs), individuals with these conditions continue to have high levels of unmet physical and mental health needs. Robust training of health professionals can help bridge this gap. A systematic review was conducted to describe the features and educational outcomes of existing postgraduate medical education curricula to inform the development of future training to address the growing unmet care needs of people with intellectual and developmental disabilities (IDD) such as ASD and ID.

METHODS

Four major databases were searched for peer-reviewed, English-language research focusing on post-graduate training in IDD education. Educational curricula and outcomes were summarized including Best Evidence in Medical Education (BEME) Quality of Evidence and Kirkpatrick training evaluation model.

RESULTS

Sixteen studies were identified with a majority published after 2000 (69%). Pediatric departments were involved in 69%, Psychiatry 19%, Medicine-Pediatrics 19%, and Family Medicine 6.3%. Analysis of Kirkpatrick outcomes showed 31% were level 1 (satisfaction or comfort); 38% level 2 (change in objective knowledge or skills); 13% level 3 (change in behavior); and none at level 4. BEME analysis showed 19% of studies were grade 1 (no clear conclusions), 31% grade 2 (ambiguous results), and half (50%) grade 3 (conclusions can probably be based on findings), with none scoring four or higher.

CONCLUSIONS

There is a paucity of objectively evaluated research in the area. Studies reviewed show clear promise for specialized, interdisciplinary, competency-based education which may be foundational for future curriculum development.

Operative list of genes associated with autism and neurodevelopmental disorders based on database review

The genetics of neurodevelopmental disorders (NDD) has made tremendous progress during the last few decades with the identification of more than 1,500 genes associated with conditions such as intellectual disability and autism. The functional roles of these genes are currently studied to uncover the biological mechanisms influencing the clinical outcome of the mutation carriers. To integrate the data, several databases and curated gene lists have been generated. Here, we provide an overview of the main databases focusing on the genetics of NDD, that are widely used by the medical and scientific communities, and extract a list of high confidence NDD genes (HC-NDD). This gene set can be used as a first filter for interpreting large scale omics dataset or for diagnostic purposes. Overall HC-NDD genes (N = 1,586) are expressed at very early stages of fetal brain development and enriched in several biological pathways such as chromosome organization, cell cycle, metabolism and synaptic function. Among those HC-NDD genes, 204 (12,9%) are listed in the synaptic gene ontology SynGO and are enriched in genes expressed after birth in the cerebellum and the cortex of the human brain. Finally, we point at several limitations regarding the relatively poor standardized information available, especially on the carriers of the mutations. Progress on the phenotypic characterization and genetic profiling of the carriers will be crucial to improve our knowledge on the biological mechanisms and on risk and protective factors for NDD.

Autism and attention-deficit/hyperactivity disorders and symptoms in children with neurofibromatosis type 1

AIM

To evaluate if autism symptoms and diagnoses are more common in children with neurofibromatosis type 1 (NF1) than in typically developing children, to which levels, and to determine if co-occurring attention-deficit/hyperactivity disorder (ADHD) symptomatology accounts for this increase.

METHOD

We searched hospital electronic medical records (EMR) for International Classification of Diseases, 10th Revision NF1 and co-occurring diagnoses codes. We recruited a subsample of 45 children (mean age 9y 2mo; SD 2y 7mo; range 5-12y; 22 males, 23 females) and collected parental reports of autism symptomatology, adaptive behavior, and behavioral problems that were compared to those of 360 age- and sex-matched controls from the Simons Simplex Collection (SSC) with autism spectrum disorder (ASD; SSC-ASD) or typically developing (SSC-TD).

RESULTS

The EMR search identified 968 children with NF1; 8.8% had ADHD and 2.1% had ASD co-occurring diagnoses. In the subsample, the mean autism scale score for participants with NF1 was below cut-off for significant autism symptoms. Participants with NF1 had significantly more autism and behavioral symptoms than SSC-TD participants, and significantly less than SSC-ASD participants, with one exception: ADHD symptom levels were similar to those of SSC-ASD participants. In analyses that controlled for internalizing, ADHD, and communication scores, the difference in autism symptom levels between participants with NF1 and typically developing controls disappeared almost entirely.

INTERPRETATION

Our results do not support an association between NF1 and autism, both at the symptom and disorder levels.

WHAT THIS PAPER ADDS

Diagnoses of attention-deficit/hyperactivity disorder (ADHD) were more common in children with neurofibromatosis type 1 (NF1) than in the general child population. Diagnoses of autism spectrum disorder were no more common in children with NF1 than in the general child population. Increases in autism symptoms did not reach clinically significant thresholds. Co-occurring ADHD symptoms accounted for increased autism questionnaire scores. Adaptive behavior in participants with NF1 showed normal socialization but lower communication proficiency.

Drug Treatment of Epilepsy Neuropsychiatric Comorbidities in Children

There is increasing recognition that epilepsy can be associated with a broad spectrum of comorbidities. While epileptic seizures are an essential element of epilepsy in children, there is a spectrum of neurological, mental health and cognitive disorders that add to the disease burden of childhood epilepsy resulting in a decreased quality of life. The most common comorbid conditions in childhood epilepsy include depression, anxiety, autism spectrum disorders, sleep disorders, attention deficits, cognitive impairment, and migraine. While epilepsy can result in comorbidities, many of the comorbidities of childhood have a bi-directional association, with the comorbid condition increasing risk for epilepsy and epilepsy increasing the risk for the comorbid condition. The bidirectional feature of epilepsy and the comorbidities suggest a common underlying pathological basis for both the seizures and comorbid condition. While recognition of the comorbid conditions of pediatric epilepsies is increasing, there has been a lag in the development of effective therapies partly out of concern that drugs used to treat the comorbid conditions could increase seizure susceptibility. There is now some evidence that most drugs used for comorbid conditions are safe and do not lower seizure threshold. Unfortunately, the evidence showing drugs are effective in treating many of the childhood comorbidities of epilepsy is quite limited. There is a great need for randomized, placebo-controlled drug trials for efficacy and safety in the treatment of comorbidities of childhood epilepsy.

Spatiotemporal distribution of autism spectrum disorder prevalence among birth cohorts during 2000-2011 in Israel

PURPOSE

Studies indicate an apparent sharp increasing trend in autism spectrum disorder (ASD) incidence and prevalence worldwide. This nationwide study aims at depicting ASD prevalence distribution in Israel in both space and time.

METHODS

Based on data from Israel National Insurance Institute, the study population included all children born in Israel 2000-2011 (n = 1,786,194), of whom 11,699 (0.655%) were subsequently diagnosed with ASD (until December 31, 2016). Prevalence was calculated and mapped by dividing the number of ASD cases within each year of birth by the number of births during that year, for each spatial unit, and similarly for several spatiotemporal levels of aggregation.

RESULTS

ASD prevalence varies substantially across different geographic areas in Israel, with considerably higher prevalence concentrated in central Israel. Strong associations were found between locality-level socioeconomic index, ethnicity, and peripherality and ASD prevalence, and even after adjustment for them, excess prevalence for ASD still persisted in certain localities. No spatial dependence of prevalence, with and without adjustment for the locality-level variables, was found (Moran's I = -0.000546, -0.00335, respectively).

CONCLUSIONS

Our findings provide important insights regarding health disparities affecting ASD diagnosis, directing further health policy intervention and further research.

Autism Spectrum Disorders in Greece: Nationwide Prevalence in 10-11 Year-Old Children and Regional Disparities

Autism spectrum disorders (ASD) constitute a public health concern with increasing prevalence worldwide. We aimed to estimate prevalence and age at diagnosis in Greece, where no large-scale prevalence study has ever been conducted. Aggregate data were collected on ASD diagnoses by gender and calendar year of diagnosis up to 2019, for children born in 2008 and 2009, from the Centers for Educational and Counseling Support, which evaluate children to receive special educational support in school. Coverage was 87.1% of centers and 88.1% of schoolchildren born in 2008–9. ASD prevalence overall was 1.15% (1.83% males, 0.44% females; ratio 4.14:1), ranging from 0.59% to 1.50% in Greece’s 13 regions. In five regions, prevalence differed significantly between centers. Overall, only 3.8% of diagnoses were made before the fourth year after birth and 42.7% before the sixth year, with considerable variation between regions. Approximate mean age at diagnosis was six years and one month, and about three months earlier for girls than for boys. Our results provide evidence-based information to guide service planning and development at national and regional levels. Particular attention should be paid to smoothing out inequalities regarding service accessibility and provision. Emphasis should be given to earlier identification and diagnosis of ASD.

Genetic and Epigenetic Etiology Underlying Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a pervasive neurodevelopmental disorder characterized by difficulties in social interaction, language development delays, repeated body movements, and markedly deteriorated activities and interests. Environmental factors, such as viral infection, parental age, and zinc deficiency, can be plausible contributors to ASD susceptibility. As ASD is highly heritable, genetic risk factors involved in neurodevelopment, neural communication, and social interaction provide important clues in explaining the etiology of ASD. Accumulated evidence also shows an important role of epigenetic factors, such as DNA methylation, histone modification, and noncoding RNA, in ASD etiology. In this review, we compiled the research published to date and described the genetic and epigenetic epidemiology together with environmental risk factors underlying the etiology of the different phenotypes of ASD.

The Female Autism Phenotype and Camouflaging: a Narrative Review

Autism is more commonly diagnosed in males than females. One explanation is the ‘female protective effect’: there is something inherent in being female which reduces the likelihood of developing autism. However, evidence suggests that the condition is underdiagnosed in females, perhaps because females express their autism in ways which do not meet current diagnostic criteria. This review explores evidence for a female-typical autism presentation, the Female Autism Phenotype (FAP) and the component of camouflaging (compensating for and masking autistic characteristics) in particular. The evidence so far supports the existence of a female-typical autism presentation, although further examination of the characteristics and their impact across all genders and ages is needed.

Bioactive Metabolites from Marine Ascidians: Future Treatment for Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a developmental disorder that influences communication and behavior. Numerous researches propose that genes can act together with manipulations from the environment to affect development in ways that lead to ASD. The broad range of issues facing people with ASD means that there is no single proper drug and treatment for ASD. Numerous shortcomings associated with the present conventional therapeutic strategies have forced researchers to venture into alternative natural sources for effective compounds. The marine environment has emerged as an alternate search environment due to its versatile conditions where organisms employ various biodefense mechanisms for their survival. Ascidians are an excellent source for unique bioactive compounds with nutritive and therapeutic content and it still holds credit for being an underused source from marine animals. Bioactive compounds isolated from ascidians have various commendable biomedical applications due to their unique chemical structures. The present chapter will focus on the potential of bioactive compounds derived from ascidians for the treatment of the neurologic disorder-ASD.

Blood platelet research in autism spectrum disorders: In search of biomarkers

Autism spectrum disorder (ASD) is a clinically heterogeneous neurodevelopmental disorder that is caused by gene-environment interactions. To improve its diagnosis and treatment, numerous efforts have been undertaken to identify reliable biomarkers for autism. None of them have delivered the holy grail that represents a reproducible, quantifiable, and sensitive biomarker. Though blood platelets are mainly known to prevent bleeding, they also play pivotal roles in cancer, inflammation, and neurological disorders. Platelets could serve as a peripheral biomarker or cellular model for autism as they share common biological and molecular characteristics with neurons. In particular, platelet-dense granules contain neurotransmitters such as serotonin and gamma-aminobutyric acid. Molecular players controlling granule formation and secretion are similarly regulated in platelets and neurons. The major platelet integrin receptor αIIbβ3 has recently been linked to ASD as a regulator of serotonin transport. Though many studies revealed associations between platelet markers and ASD, there is an important knowledge gap in linking these markers with autism and explaining the altered platelet phenotypes detected in autism patients. The present review enumerates studies of different biomarkers detected in ASD using platelets and highlights the future needs to bring this research to the next level and advance our understanding of this complex disorder.

Prevalence and Characteristics of Autism Spectrum Disorder Among Spanish School-Age Children

The present study aims to assess the prevalence of autism spectrum disorder (ASD) in preschool and school-age children following a two-phase procedure. The screening phase was performed on a sample of 5555 children taking into account parent and teacher information. The individual assessment included the ADI-R, ADOS-2 and Wechsler scales. The estimated prevalence was 1.55% in preschoolers and 1.00% in school-age children. Between 1.84 and 2.59% of the children exhibited subclinical diagnosis. The male-to-female ratio was around 4:1. Most of the children exhibited mild and moderate nuclear symptoms, and the girls showed less severe communication problems. Previous diagnosis was found in 62-71% of the children. Prevalence estimates are close to the 1% international ratings and much higher than previous national reports suggested.

Temporal and Geographical Variability of Prevalence and Incidence of Autism Spectrum Disorder Diagnoses in Children in Catalonia, Spain

This study aims to estimate the prevalence of autism spectrum disorders (ASD) in 2017 and the ASD diagnosis incidence between 2009 and 2017 in children living in Catalonia region in Spain, and their temporal and geographical variability. We used administrative data for all children aged 2–17 years who were insured in the public Catalan Health System between 2009 and 2017. We identified all ASD cases diagnosed between 2009 and 2017 (ICD‐9 codes 299.0, 299.1, 299.8, and 299.9). We estimated the ASD prevalence in 2017 and the overall annual incidence between 2009 and 2017, then stratified by sex, age group, and healthcare area. We used Poisson regression models to assess temporal trends in the incidence and mixed‐effects Poisson regression models to assess geographical variability. We observed an ASD prevalence of 1.23% (95% confidence interval [CI] 1.21–1.25) in 2017, with 1.95% (95% CI 1.92–1.99) for boys and 0.46% (95% CI 0.44–0.48) for girls, the highest prevalence being in 11‐ to 17‐year‐olds (1.80%, 95% CI 1.76–1.83). The ASD diagnosis incidence increased from 0.07% (95% CI 0.06–0.09) in 2009 to 0.23% (95% CI 0.21–0.24) in 2017, with a higher increase in girls, and in children aged 2–5 years at the time of diagnosis. We only observed geographical differences in prevalence in the 2017 data. We also detected a threefold increase in the diagnosis incidence overall, which was even more pronounced in girls and at early ages. In conclusion, the ASD prevalence observed in this study was 1.23% in 2017, with a sex ratio of 4.5 in favor of boys, which is consistent with previous studies. Autism Res2019. © 2019 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Autism spectrum disorders (ASD) are currently well known in our society as one of the most common neurodevelopmental disorders during childhood. The results of our study showed that, in 2017 in Catalonia, slightly more than one in a 100 children had an ASD diagnosis, it was more common in boys than in girls, and also in older children. In addition, between 2009 and 2017, we observed an increase in the number of new cases diagnosed each year. The data presented in this study will assist in planning and evaluating the needs of health services in this geographical region.

Congenital Cytomegalovirus Infection in Children with Autism Spectrum Disorder: Systematic Review and Meta-Analysis

Association of congenital cytomegalovirus (CMV) infection with autism spectral disorder (ASD) has been suggested since 1980s. Despite the observed association, its role as a risk factor for ASD remains to be defined. In the present review, we systematically evaluated the available evidence associating congenital CMV infection with ASD using PubMed, Web of Science, Cochrane Library, and Embase databases. Any studies on children with CMV infection and ASD were evaluated for eligibility and three observational studies were included in meta-analysis. Although a high prevalence of congenital CMV infection in ASD cases (OR 11.31, 95% CI 3.07-41.66) was indicated, too few events (0-2 events) in all included studies imposed serious limitations. There is urgent need for further studies to clarify this issue.

Focus on the Social Aspect of Autism

Autism spectrum disorder (ASD) describes a set of neurodevelopmental disorders. Despite extensive ASD research lasting more than 60 years, its causes are still unknown. Without indicating the etiology, its development cannot be stopped. Over the years, both the definition and diagnostic criteria have developed. The number of ASD incidence is rising. The economical aspect should also be highlighted. This disorder presents particular challenges to affected children, their parents and physicians. The research of ASD, physician activities, policy making and raising the level of awareness must be coordinated. Special attention should be paid to the problem among adults with ASD.

Risk of autistic spectrum disorder in offspring with parental mood disorders: A systematic review and meta-analysis

BACKGROUND

The association between mood disorders in parents and autism spectrum disorder (ASD) risk in offspring has been investigated in several studies, but the evidence is inconclusive. This systematic review and meta-analysis will explore whether an association exists between parental mood disorders and ASD risk in offspring.

METHODS

A literature search was performed using the electronic databases PubMed, EMBASE, PsycINFO, and Scopus. We also reviewed reference lists from retrieved articles. Meta-analysis was conducted, and combined effect values and their 95% confidence intervals were calculated. Study-specific risk ratios (RRs) were pooled using a random effect model. The risk of publication bias was assessed by funnel plot and Egger's regression asymmetry test.

RESULTS

Nine observational studies (two cohort and seven case-control studies) were included for analysis. Our meta-analysis found a greater risk of ASD in children exposed to parental affective, depressive, and bipolar disorders [(RRs 1.65 (95%CI 1.45-1.88); 1.37 (95%CI 1.04-1.81) and 1.87; 95%CI 1.69-2.07) respectively]. We also found increased ASD risk in children of mothers who experienced affective and depressive disorders [(RRs 1.67 (95%CI 1.34-2.09) and 1.62 (95%CI 1.32-1.99) respectively]. We found no increased risk of ASD in children exposed to paternal affective and depressive disorders. Subgroup and sensitivity analysis confirmed the robustness of our main analysis.

CONCLUSION

The evidence from the present study suggests parental affective, depressive and bipolar, as well as maternal affective and depressive disorders increased the risk of ASD in offspring. Exposure to affective and depressive disorders in fathers only was not linked with ASD risk in children.

Autism Spectrum Disorder: Incidence and Time Trends Over Two Decades in a Population-Based Birth Cohort

We retrospectively identified autism spectrum disorder (ASD) incident cases among 31,220 individuals in a population-based birth cohort based on signs and symptoms uniformly abstracted from medical and educational records. Inclusive and narrow research definitions of ASD (ASD-RI and ASD-RN, respectively) were explored, along with clinical diagnoses of ASD (ASD-C) obtained from the records. The incidence of ASD-RI, ASD-RN, and ASD-C increased significantly from 1985 to 1998, then ASD-RI and ASD-RN plateaued while the rate of ASD-C continued to increase during 1998-2004. The rising incidence of research-defined ASD may reflect improved recognition and documentation of ASD signs and symptoms. Although the frequency of threshold ASD symptoms stabilized, the rate of ASD-C continued to increase, narrowing the gap between clinical ascertainment and symptom documentation.

Epilepsy and Autism Spectrum Disorder: An Epidemiological Study in Shanghai, China

Autism spectrum disorder (ASD) is a neurodevelopmental disease that may involve various brain abnormalities. However, there are few large epidemiological studies on the relation between epilepsy and ASD in terms of different genders and ages. This study aimed to evaluate the relation between epilepsy and ASD based on 74,251 Chinese children aged 3-12 years who were recruited from kindergartens and primary schools in China. ASD was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-V), and verification of epilepsy was based on medical records. The enrolled children diagnosed with ASD were examined by magnetic resonance imaging (MRI) and took genetic tests to rule out other neurological and congenital diseases. The raw odds ratio (OR) was 60.53 [95% confidence interval (CI) = 37.80-96.92, P < 0.01] for epilepsy and ASD, and the adjusted OR was 38.99 (95% CI = 20.70-73.41, P < 0.01) after controlling for the confounders. Moreover, the adjusted OR was significantly higher in girls (OR = 45.26, 95% CI = 16.42-124.76, P < 0.01) than in boys (OR = 32.64, 95% CI = 14.33-74.34, P < 0.01). Among children with younger age, the adjusted OR was the highest (OR = 75.12, 95% CI = 22.80-247.48.16, P < 0.01). These findings suggest that epilepsy might be closely linked to the development of ASD, especially for early-onset epilepsy and among girls.

Advances in Biomarker Studies in Autism Spectrum Disorders

Autism spectrum disorder (ASD) is a neurological and developmental condition that begins early in childhood and lasts throughout life. The epidemiology of ASD is continuously increasing all over the world with huge social and economical burdens. As the etiology of autism is not completely understood, there is still no medication available for the treatment of this disorder. However, some behavioral interventions are available to improve the core and associated symptoms of autism, particularly when initiated at an early stage. Thus, there is an increasing demand for finding biomarkers for ASD. Although diagnostic biomarkers have not yet been established, research efforts have been carried out in neuroimaging and biological analyses including genomics and gene testing, proteomics, metabolomics, transcriptomics, and studies of the immune system, inflammation, and microRNAs. Here, we will review the current progress in these fields and focus on new methods, developments, research strategies, and studies of blood-based biomarkers.

Prevalence of Autism Spectrum Disorder in a large Italian catchment area: a school-based population study within the ASDEU project

AIMS

This study aims to estimate Autism Spectrum Disorders (ASD) prevalence in school-aged children in the province of Pisa (Italy) using the strategy of the ASD in the European Union (ASDEU) project.

METHODS

A multistage approach was used to identify cases in a community sample (N = 10 138) of 7-9-year-old children attending elementary schools in Pisa - Italy. First, the number of children with a disability certificate was collected from the Local Health Authority and an ASD diagnosis was verified by the ASDEU team. Second, a Teacher Nomination form (TN) to identify children at risk for ASD was filled in by teachers who joined the study and the Social Communication Questionnaire (SCQ) was filled in by the parents of children identified as positive by the TN; a comprehensive assessment, which included the Autism Diagnostic Observation Schedule-Second Edition, was performed for children with positive TN and SCQ⩾9.

RESULTS

A total of 81 children who had a disability certificate also had ASD (prevalence: 0.79%, i.e. 1/126). Specifically, 66 children (57 males and nine females; 62% with intellectual disability -ID-) were certified with ASD, whereas another 15 (11 males and four females; 80% with ID) were recognised as having ASD among those certified with another neurodevelopmental disorder. Considering the population of 4417 (children belonging to schools which agreed to participate in the TN/SCQ procedure) and using only the number of children certified with ASD, the prevalence (38 in 4417) was 0.86%, i.e. one in 116. As far as this population is concerned, the prevalence rises to 1% if we consider the eight new cases (six males and two females; no subject had ID) identified among children with no pre-existing diagnoses and to 1.15%, i.e., one in 87, if probabilistic estimation is used.

CONCLUSIONS

This is the first population-based ASD prevalence study conducted in Italy so far and its results indicate a prevalence of ASD in children aged 7-9 years of about one in 87. This finding may help regional, national and international health planners to improve ASD policies for ASD children and their families in the public healthcare system.

Sex: A Significant Risk Factor for Neurodevelopmental and Neurodegenerative Disorders

Males and females sometimes significantly differ in their propensity to develop neurological disorders. Females suffer more from mood disorders such as depression and anxiety, whereas males are more susceptible to deficits in the dopamine system including Parkinson's disease (PD), attention-deficit hyperactivity disorder (ADHD) and autism. Despite this, biological sex is rarely considered when making treatment decisions in neurological disorders. A better understanding of the molecular mechanism(s) underlying sex differences in the healthy and diseased brain will help to devise diagnostic and therapeutic strategies optimal for each sex. Thus, the aim of this review is to discuss the available evidence on sex differences in neuropsychiatric and neurodegenerative disorders regarding prevalence, progression, symptoms and response to therapy. We also discuss the sex-related factors such as gonadal sex hormones and sex chromosome genes and how these might help to explain some of the clinically observed sex differences in these disorders. In particular, we highlight the emerging role of the Y-chromosome gene, SRY, in the male brain and its potential role as a male-specific risk factor for disorders such as PD, autism, and ADHD in many individuals.

Social impairment of children with autism spectrum disorder affects parental quality of life in different ways

This study evaluated the life quality of Chinese parents of preschool children with autism spectrum disorder (ASD) and their association with child social impairment and childcare burden. The participants included 406 families of children with ASD and 513 families with typically developing (TD) children. The findings indicated that parents in the ASD group had a lower quality of life than parents in the TD group, whereas only mother of children with ASD experienced a greater childcare burden than mother with TD children. Lower parental quality of life were associated with higher social impairment of children. To further clarify the correlativity of child social impairment, parental quality of life and childcare burden, the mediation analyses were conducted. The results showed that childcare burden mediated the influence of child social impairment on maternal quality of life, while it has no mediating effect on fathers. It implies that social impairment of children affects parental quality of life in different ways.

Pregnancy risk factors related to autism: an Italian case-control study in mothers of children with autism spectrum disorders (ASD), their siblings and of typically developing children

This study, carried out in two Italian Institutions, assesses the frequency of 27 potential autism risk factors related to pregnancy and peri- and postnatal periods by interviewing mothers who had children with autism, children with autism and one or two typically developing siblings, or only typically developing children. The clinical sample included three case groups: 73 children and adolescents with autism (Group A), 35 children and adolescents with autism (Group A1) having 45 siblings (Group B) and 96 typically developing children (Group C) matched for gender and age. Twenty-five out of 27 of risk factors presented a higher frequency in Group A in comparison with Group C and for nine of them a statistically significant difference was found. Twenty-one out of 27 of risk factors presented a higher frequency in Group A in comparison with Group B. A higher prevalence of environmental risk factors was observed in 11 risk factors in the Group A1 in comparison with Group B and for nine of them an odds ratio higher than 1.5 was found. For 13 factors there was a progressive increase in frequency going from Group C, B and A and a statistically higher prevalence of the mean number of stressful events per pregnancy was recorded in Group A when compared with Groups B and C. The results suggest that environmental, incidental phenomena and stressful life events can influence pregnancy outcome in predisposed subjects, pointing out a possible threshold effect in women who are predisposed to have suboptimal pregnancies.

Early Detection and Intervention of ASD: A European Overview

Over the last several years there has been an increasing focus on early detection of Autism Spectrum Disorder (ASD), not only from the scientific field but also from professional associations and public health systems all across Europe. Not surprisingly, in order to offer better services and quality of life for both children with ASD and their families, different screening procedures and tools have been developed for early assessment and intervention. However, current evidence is needed for healthcare providers and policy makers to be able to implement specific measures and increase autism awareness in European communities. The general aim of this review is to address the latest and most relevant issues related to early detection and treatments. The specific objectives are (1) analyse the impact, describing advantages and drawbacks, of screening procedures based on standardized tests, surveillance programmes, or other observational measures; and (2) provide a European framework of early intervention programmes and practices and what has been learnt from implementing them in public or private settings. This analysis is then discussed and best practices are suggested to help professionals, health systems and policy makers to improve their local procedures or to develop new proposals for early detection and intervention programmes.

Assessing autism at its social and developmental roots: A review of Autism Spectrum Disorder studies using functional near-infrared spectroscopy

We review a relatively new method for studying the developing brain in children and infants with Autism Spectrum Disorder (ASD). Despite advances in behavioral screening and brain imaging, due to paradigms that do not easily allow for testing of awake, very young, and socially-engaged children-i.e., the social and the baby brain-the biological underpinnings of this disorder remain a mystery. We introduce an approach based on functional near-infrared spectroscopy (fNIRS), which offers a noninvasive imaging technique for studying functional activations by measuring changes in the brain's hemodynamic properties. This further enables measurement of brain activation in upright, interactive settings, while maintaining general equivalence to fMRI findings. We review the existing studies that have used fNIRS for ASD, discussing their promise, limitations, and their technical aspects, gearing this study to the researcher who may be new to this technique and highlighting potential targets for future research.

A review of prevalence studies of Autism Spectrum Disorder by latitude and solar irradiance impact

Autism Spectrum Disorder (ASD) is a lifelong disability with no known cause or cure. Among the suggested etiologies, is Cannell's hypothesis of a deficiency in Vitamin D the main natural source of which is Solar Ultraviolet-B (UVB) radiation. The aim in this paper is to build on this hypothesis and explore the relationship of solar irradiance of which UVB is a component, by latitude with the prevalence rates of ASD. Twenty-five reports published between 2011 and 2016 using comparable diagnostic criteria were reviewed. The results suggest a tendency for the prevalence rates of ASD to be lowest in countries near the equator and for this rate to increase as the latitude increases. These findings provide some support not just for the Vitamin D hypothesis, but also for a new proposition that along with UVB radiation, the entire solar radiation spectrum which reaches the earth, may play a role in ASD. While these results are both novel and encouraging in terms of the potential efficacy of exposure to natural sunlight, further research is warranted before results can be considered definitive, and before the implications of the findings can be implemented clinically.

EDUTEA: A DSM-5 teacher screening questionnaire for autism spectrum disorder and social pragmatic communication disorder

Teacher's reports about child psychopathology are often useful because they make it possible to compare children's development within their normative peer group. The EDUTEA questionnaire aims to provide clinicians and researchers with a brief tool that can be used to screen autism spectrum disorders and social communication disorders in school settings. Method: It was designed according to DSM-5 criteria and validated in a sample of 2,660 Spanish schoolers. Results: The EDUTEA showed a two-factor structure with high internal reliability: Social communication impairments (α=.95) and Restricted behaviour patterns (α=.93). The ROC curve showed that the area under the curve was highly predictive (.90). We propose using a cut-off score of 10, which gives high values of sensitivity (87%), specificity (91.2%) and positive predictive value (.87). Moderate correlations were found with the severity score of the Autism Diagnostic Observation Schedule (ADOS-2) and the child pragmatic competence. Conclusions: The EDUTEA could be useful in ASD screening protocols in schools.

What Is the Male-to-Female Ratio in Autism Spectrum Disorder? A Systematic Review and Meta-Analysis

OBJECTIVE

To derive the first systematically calculated estimate of the relative proportion of boys and girls with autism spectrum disorder (ASD) through a meta-analysis of prevalence studies conducted since the introduction of the DSM-IV and the International Classification of Diseases, Tenth Revision.

METHOD

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. The Medline, Embase, and PsycINFO databases were searched, and study quality was rated using a risk-of-bias tool. Random-effects meta-analysis was used. The pooled outcome measurement was the male-to-female odds ratio (MFOR), namely the odds of being male in the group with ASD compared with the non-ASD group. In effect, this is the ASD male-to-female ratio, controlling for the male-to-female ratio among participants without ASD.

RESULTS

Fifty-four studies were analyzed, with 13,784,284 participants, of whom 53,712 had ASD (43,972 boys and 9,740 girls). The overall pooled MFOR was 4.20 (95% CI 3.84-4.60), but there was very substantial between-study variability (I² = 90.9%). High-quality studies had a lower MFOR (3.32; 95% CI 2.88-3.84). Studies that screened the general population to identify participants regardless of whether they already had an ASD diagnosis showed a lower MFOR (3.25; 95% CI 2.93-3.62) than studies that only ascertained participants with a pre-existing ASD diagnosis (MFOR 4.56; 95% CI 4.10-5.07).

CONCLUSION

Of children meeting criteria for ASD, the true male-to-female ratio is not 4:1, as is often assumed; rather, it is closer to 3:1. There appears to be a diagnostic gender bias, meaning that girls who meet criteria for ASD are at disproportionate risk of not receiving a clinical diagnosis.

Cross-disorder comparative analysis of comorbid conditions reveals novel autism candidate genes

BACKGROUND

Numerous studies have highlighted the elevated degree of comorbidity associated with autism spectrum disorder (ASD). These comorbid conditions may add further impairments to individuals with autism and are substantially more prevalent compared to neurotypical populations. These high rates of comorbidity are not surprising taking into account the overlap of symptoms that ASD shares with other pathologies. From a research perspective, this suggests common molecular mechanisms involved in these conditions. Therefore, identifying crucial genes in the overlap between ASD and these comorbid disorders may help unravel the common biological processes involved and, ultimately, shed some light in the understanding of autism etiology.

RESULTS

In this work, we used a two-fold systems biology approach specially focused on biological processes and gene networks to conduct a comparative analysis of autism with 31 frequently comorbid disorders in order to define a multi-disorder subcomponent of ASD and predict new genes of potential relevance to ASD etiology. We validated our predictions by determining the significance of our candidate genes in high throughput transcriptome expression profiling studies. Using prior knowledge of disease-related biological processes and the interaction networks of the disorders related to autism, we identified a set of 19 genes not previously linked to ASD that were significantly differentially regulated in individuals with autism. In addition, these genes were of potential etiologic relevance to autism, given their enriched roles in neurological processes crucial for optimal brain development and function, learning and memory, cognition and social behavior.

CONCLUSIONS

Taken together, our approach represents a novel perspective of autism from the point of view of related comorbid disorders and proposes a model by which prior knowledge of interaction networks may enlighten and focus the genome-wide search for autism candidate genes to better define the genetic heterogeneity of ASD.

Association of oligodendrocytes differentiation regulator gene DUSP15 with autism

OBJECTIVES

Autism is a pervasive neurodevelopmental disorder with high heritability. Genetic factors play crucial roles in the aetiology of autism. Dual specificity phosphatase 15 (DUSP15) has been recognised as a key regulator gene for oligodendrocytes differentiation. A previous study detected one de novo missense variant (p.Thr107Met) with probable deleterious function in exon 6 of DUSP15 among patients with autism. Therefore, we sequenced this mutation in autistic children and performed an association analysis between DUSP15 polymorphisms and autism.

METHODS

We performed a case-control study between 255 children affected with autism and 427 healthy controls. Four tag-single nucleotide polymorphisms (SNPs) were selected. These SNPs and the previously reported mutation in exon 6 of DUSP15 were genotyped via Sanger sequencing.

RESULTS

Our results showed that rs3746599 was significantly associated with autism under allelic, additive and dominant models, respectively (χ²=9.699, P = 0.0018; χ²=16.224, P = 0.001; χ²=7.198, P = 0.007). The association remained significant after Bonferroni correction and permutation tests (n = 10,000). We did not detect the missense variant p.Thr107Met reported in previous studies. However, a de novo missense variant of DUSP15 (p.Ala56Thr) with a probable disease-causing effect was detected in one autistic child while absent in healthy controls.

CONCLUSIONS

Our findings initially suggest that DUSP15 might be a susceptibility gene for autism in Chinese Han population.

Epidemiology of autism in adults across age groups and ability levels

BACKGROUND

The epidemiology of autism in adults has relied on untested projections using childhood research.

AIMS

To derive representative estimates of the prevalence of autism and key associations in adults of all ages and ability levels.

METHOD

Comparable clinical diagnostic assessments of 7274 Adult Psychiatric Morbidity Survey participants combined with a population case-register survey of 290 adults with intellectual disability.

RESULTS

The combined prevalence of autism in adults of all ages in England was 11/1000 (95% CI 3-19/1000). It was higher in those with moderate to profound intellectual disability (odds ratio (OR) = 63.5, 95% CI 27.4-147.2). Male gender was a strong predictor of autism only in those with no or mild intellectual disability (adjusted OR = 8.5, 95% CI 2.0-34.9; interaction with gender, P = 0.03).

CONCLUSIONS

Few adults with autism have intellectual disability; however, autism is more prevalent in this population. Autism measures may miss more women with autism.

Beneficial Effects of Co-Ultramicronized Palmitoylethanolamide/Luteolin in a Mouse Model of Autism and in a Case Report of Autism

AIMS

Autism spectrum disorder (ASD) is a condition defined by social communication deficits and repetitive restrictive behaviors. Association of the fatty acid amide palmitoylethanolamide (PEA) with the flavonoid luteolin displays neuroprotective and antiinflammatory actions in different models of central nervous system pathologies. We hypothesized that association of PEA with luteolin might have therapeutic utility in ASD, and we employed a well-recognized autism animal model, namely sodium valproate administration, to evaluate cognitive and motor deficits.

METHODS

Two sets of experiments were conducted. In the first, we investigated the effect of association of ultramicronized PEA with luteolin, co-ultramicronized PEA-LUT® (co-ultraPEA-LUT®) in a murine model of autistic behaviors, while in the second, the effect of co-ultraPEA-LUT® in a patient affected by ASD was examined.

RESULTS

Co-ultraPEA-LUT® treatment ameliorated social and nonsocial behaviors in valproic acid-induced autistic mice and improved clinical picture with reduction in stereotypes in a 10-year-old male child.

CONCLUSION

These data suggest that ASD symptomatology may be improved by agents documented to control activation of mast cells and microglia. Co-ultraPEA-LUT® might be a valid and safe therapy for the symptoms of ASD alone or in combination with other used drugs.

Quality of life of high-functioning children and youth with autism spectrum disorder and typically developing peers: Self- and proxy-reports

Studies have shown parents to report lower quality of life for their children with autism spectrum disorder than children's self-report scores and the same applies for data on typically developing children. Our objectives were to: (1) explore how high-functioning children with autism spectrum disorder rate their quality of life compared with paired controls without autism spectrum disorder; (2) explore how parents of high-functioning children with autism spectrum disorder rate their children's quality of life compared with parents of paired controls; and (3) compare child self-reports of quality of life with their parent's proxy-reports for both groups of children. Data were collected with the Icelandic self- and proxy-reported versions of the KIDSCREEN-27. Reports of 96 children with autism spectrum disorder, 211 controls and their parents were included in the analyses. Compared with controls, children with autism spectrum disorder had lower means on all quality of life dimensions. Parents of children with autism spectrum disorder evaluated their children's quality of life lower on all dimensions than did parents of controls. On four out of five dimensions, children with autism spectrum disorder reported better quality of life than did their parents. Despite differences in ratings children with autism spectrum disorder and their parents agreed on the most problematic dimensions, namely, social support and peers and physical well-being. Our results highlight the importance of seeking the viewpoints of both children and their parents.

Community participation and environment of children with and without autism spectrum disorder: parent perspectives

AIM

This study explored parent perspectives of participation patterns and environmental supports and barriers for high-functioning children with autism spectrum disorder (ASD) within their communities compared with a group of children without ASD.

METHOD

The Participation and Environment Measure for Children and Youth was used to gather online data from parents of 99 children with ASD and 241 children without ASD. Mann-Whitney U test and chi-square tests were used to explore differences between groups and Cohen's d was calculated to examine effect sizes.

RESULTS

Significant differences between children with and without ASD were observed for all participation and environment summary scores. Children with ASD participated less frequently, were less involved, and their parents were less satisfied with their child's participation in community-based activities. Parents of children with ASD also identified fewer supports for their child's participation and more environmental barriers than other parents.

CONCLUSION

Children with ASD participated less in community-related activities than children without ASD as perceived by their parents. Barriers limiting community participation included features of the social and physical environment and limited resources.

SIGNIFICANCE

Occupational therapists should focus on decreasing environmental challenges in their efforts to facilitate participation of children with ASD in the community.