Epidemiological surveys of ASD: advances and remaining challenges

Potential key pathophysiological participant and treatment target in autism spectrum disorder: Microglia

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by social and communication deficits, as well as restricted or repetitive behaviors or interests. Although the etiology of ASD remains unclear, there is abundant evidence suggesting that microglial dysfunction is likely to be a significant factor in the pathophysiology of ASD. Microglia, the primary innate immune cells in the central nervous system (CNS), play a crucial role in brain development and homeostasis. Recently, numerous studies have shown that microglia in ASD models display various abnormalities including morphology, function, cellular interactions, genetic and epigenetic factors, as well as the expression of receptors, transcription factors, and cytokines. They impact normal neural development through various mechanisms contributing to ASD, such as neuroinflammation, and alterations in synaptic formation and pruning. The focus of this review is on recent studies regarding microglial abnormalities in ASD and their effects on the onset and progression of ASD at both cellular and molecular levels. It can provide insight into the specific contribution of microglia to ASD pathogenesis and help in designing potential therapeutic and preventative strategies targeting microglia.

Acquisition Time for Resting-State HbO/Hb Coupling Measured by Functional Near-Infrared Spectroscopy in Assessing Autism

Functional near-infrared spectroscopy was used to record spontaneous hemodynamic fluctuations form the bilateral temporal lobes in 25 children with autism spectrum disorder (ASD) and 22 typically developing (TD) children. The coupling between oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (Hb) was calculated by Pearson correlation coefficient, showing significant difference between ASD and TD, thus the coupling could be a characteristic feature for ASD. To evaluate the discrimination ability of the feature obtained in different acquisition times, the receiver operating characteristic curve (ROC) was constructed and the area under curve (AUC) was calculated. The results showed AUC > 0.8 when the time duration was longer than 1.5 min, but longer than 4 min, AUC value (~0.87) hardly varied, implying the maximal discrimination ability reached. This study demonstrated the coupling could be one of characteristic features for ASD even acquired in a short measurement time.

Prevalence, incidence, and characteristics of autism spectrum disorder among children in Beijing, China

LAY ABSTRACT

It is the first study to explore the prevalence, incidence, and co-occurring conditions of autism spectrum disorder for the preschoolers in China. The prevalence and incidence of autism spectrum disorder has increased in recent decades. Autism spectrum disorder has become an important public concern worldwide. In this study, all hospital confirmed cases had an associated diagnosis (International Classification of Diseases, 10th revision (ICD-10) codes: F84.0, 84.5, F84.9). In total, 4457 children aged 4-6 years were identified as having autism spectrum disorder. In 2021, 1 in 95 children aged 6 years, 1 in 115 children aged 5 years, and 1 in 130 children aged 4 years were estimated to have autism spectrum disorder in Beijing. The incidence was 0.11% in 2019 and increased to 0.18% in 2021. There has been a great emphasis on the importance of early autism spectrum disorder diagnosis in large cities in China.

Risk of physical health comorbidities in autistic adults: clinical nested cross-sectional study

BACKGROUND

Physical health conditions are more common in individuals with autism. Some, like epilepsy, have considerable evidence supporting their increased prevalence, but many diseases lack literature to make strong conclusions.

AIMS

To investigate the prevalence of physical health comorbidities in autism.

METHOD

We undertook a nested cross-sectional study, using a sample from the National Centre for Mental Health database. It included participants from England and Wales who reported a clinician-made diagnosis of autism (n = 813), and a control sample without autism or mental illness (n = 2781). Participants had provided a medical history at enrolment. Analysis was carried out by binomial logistic regressions controlling for age, gender, smoking status, and antipsychotic and mood stabiliser use. A subanalysis of individuals with concurrent intellectual disability (n = 86) used binomial logistic regression with the same control variables.

RESULTS

Many physical health conditions were significantly more common in autism. Sixteen out of 28 conditions showed increased odds, with the highest odds ratios observed for liver disease, chronic obstructive pulmonary disease, kidney disease, osteoporosis and rheumatoid arthritis. A subanalysis demonstrated a similar pattern of physical health in individuals with autism with and without concurrent intellectual disability. Some conditions, including osteoporosis, hyperthyroidism, head injury and liver disease, had larger odds ratios in individuals with concurrent intellectual disability.

CONCLUSIONS

Physical health conditions occur more commonly in individuals with autism, and certain conditions are further increased in those with concurrent intellectual disability. Our findings contribute to prior evidence, including novel associations, and suggest that people with autism are at greater risk of physical health problems throughout adulthood.

Transient CSF1R inhibition ameliorates behavioral deficits in Cntnap2 knockout and valproic acid-exposed mouse models of autism

Microglial abnormality and heterogeneity are observed in autism spectrum disorder (ASD) patients and animal models of ASD. Microglial depletion by colony stimulating factor 1-receptor (CSF1R) inhibition has been proved to improve autism-like behaviors in maternal immune activation mouse offspring. However, it is unclear whether CSF1R inhibition has extensive effectiveness and pharmacological heterogeneity in treating autism models caused by genetic and environmental risk factors. Here, we report pharmacological functions and cellular mechanisms of PLX5622, a small-molecule CSF1R inhibitor, in treating Cntnap2 knockout and valproic acid (VPA)-exposed autism model mice. For the Cntnap2 knockout mice, PLX5622 can improve their social ability and reciprocal social behavior, slow down their hyperactivity in open field and repetitive grooming behavior, and enhance their nesting ability. For the VPA model mice, PLX5622 can enhance their social ability and social novelty, and alleviate their anxiety behavior, repetitive and stereotyped autism-like behaviors such as grooming and marble burying. At the cellular level, PLX5622 restores the morphology and/or number of microglia in the somatosensory cortex, striatum, and hippocampal CA1 regions of the two models. Specially, PLX5622 corrects neurophysiological abnormalities in the striatum of the Cntnap2 knockout mice, and in the somatosensory cortex, striatum, and hippocampal CA1 regions of the VPA model mice. Incidentally, microglial dynamic changes in the VPA model mice are also reported. Our study demonstrates that microglial depletion and repopulation by transient CSF1R inhibition is effective, and however, has differential pharmacological functions and cellular mechanisms in rescuing behavioral deficits in the two autism models.

Demographic and autism characteristics as predictors of age of autism diagnosis of individuals with autism in Paraguay

LAY ABSTRACT

Autism is a lifelong condition characterized by repetitive behaviors and social communication differences. The reported cases of autism increased globally in the past years. Detecting autism early and providing appropriate supports promptly are crucial for better outcomes. Yet, little research focuses on what factors interplay in the diagnostic process of autistic children in Paraguay. We gathered data from 176 caregivers of autistic children under 18 years in Paraguay. Through a detailed analysis, we found that child's age, child's age at the caregiver's first concerns about their development, and the child's verbal skills are key in predicting the age of autism diagnosis in Paraguay. Educating caregivers and professionals about autism and social communication development can help identify autism early and provide timely support.

Genetic etiology of autism spectrum disorder in the African population: a scoping review

Background

Autism spectrum disorder (ASD) is a neurodevelopmental disorder (NDD) characterized by significant impairments in social, communicative, and behavioral abilities. However, only a limited number of studies address the genetic basis of ASD in the African population. This study aims to document the genes associated with ASD in Africa and the techniques used to identify them. Additionally, genes identified elsewhere but not yet in Africa are also noted.

Methods

Online databases such as Wiley Online Library, PubMed, and Africa Journal Online were used. The review was conducted using the keyword related to genetic and genomic ASD study in the African population.

Result

In this scoping review, 40 genetic studies on ASD in Africa were reviewed. The Egyptian and South African populations were the most studied, with 25 and 5 studies, respectively. Countries with fewer studies included Tunisia (4), East African countries (3), Libya (1), Nigeria (1), and Morocco (1). Some 61 genes responsible for ASD were identified in the African population: 26 were identified using a polymerase chain reaction (PCR)-based method, 22 were identified using sequencing technologies, and 12 genes and one de novo chromosomal aberration were identified through other techniques. No African study identified any ASD gene with genome-wide association studies (GWAS). Notably, at least 20 ASD risk genes reported in non-African countries were yet to be confirmed in Africa's population.

Conclusion

There are insufficient genetic studies on ASD in the African population, with sample size being a major limitation in most genetic association studies, leading to inconclusive results. Thus, there is a need to conduct more studies with large sample sizes to identify other genes associated with ASD in Africa's population using high-throughput sequencing technology.

Complete Spectrum of Physical Comorbidities with Autism Spectrum Disorder in a Nationwide Cohort

The associations between autism spectrum disorder (ASD) and physical diseases (PD) based on ICD-8 and ICD-10 diagnoses were studied, comparing with the risks of the general population. All individuals diagnosed before 30th April 2018 with ASD (n = 12,063) and a 5% random sample of the general population (n = 41,251) were drawn from Danish registers of the birth cohorts 1984-1995. For each of the entire spectrum of 13 PD categories, participants were followed from birth to first diagnosis, death, emigration, or 31st December 2017, whichever came first. Time from inclusion at birth to time of first physical diagnosis, accounting for censoring, was studied by use of time-stratified Cox models. When compared to the control sample, the individuals with ASD had a substantial added immediate risk in infancy and in childhood for 12 of the 13 categories. Particularly prominent were estimated associations for nervous system diseases at ages 0-9, and diseases of the eye and adnexa at ages 0-11. The associations were observed for both sexes, but were stronger among females than males, especially for genitourinary system diseases. On the cumulative scale, individuals with ASD were at pronounced greater risk through follow-up for 8 categories, with the greatest cumulative risk of respiratory system diseases, which at ages 5 and 30 was 24.9% and 41.5% for the ASD cohort while for the control sample it was 16.3% and 34.5% at the same ages. Especially in infancy and childhood, the present study found increased risks for a multitude of physical diseases.

"It Seems Much More Enjoyable Now": Parental Perception of Relational Change from Participating in Paediatric Autism Communication Therapy (PACT)

OBJECTIVES

This qualitative study aims to examine parental experiences of feasibility and relational changes from participating in the Paediatric Autism Communication Therapy (PACT) intervention.

METHODS

Thirteen parents of children diagnosed with autism spectrum disorder (mean age 3.89 years) participated in semi-structured interviews. Thematic analysis was performed, inspired by an abductive approach informed by the theories of the attachment system, the caregiving system and mentalisation.

RESULTS

Three overarching themes were identified: the struggle of fitting PACT into everyday life, the fruit of relational connection and the cascading relational effects of PACT. Parents were challenged regarding finding time for the intervention but adapted PACT to their individual needs and possibilities. All parents experienced relational improvement, and a cycle of positive relational change through PACT was identified.

CONCLUSIONS

This study has several clinical implications. Therapists and clinics offering PACT interventions should encourage and support parents in their individual journey of implementing PACT into their everyday lives. Some of the parents described improvements in parental mentalisation, child attachment and mutual enjoyment in the parent-child relationship. Children with autism could benefit from parents increasing their sensitivity when caregiving, and clinicians may through interventions such as PACT facilitate this development.

Feedback Loop Failure Modes in Medical Diagnosis: How Biases Can Emerge and Be Reinforced

BACKGROUND

Medical diagnosis in practice connects to research through continuous feedback loops: Studies of diagnosed cases shape our understanding of disease, which shapes future diagnostic practice. Without accounting for an imperfect and complex diagnostic process in which some cases are more likely to be diagnosed correctly (or diagnosed at all), the feedback loop can inadvertently exacerbate future diagnostic errors and biases.

FRAMEWORK

A feedback loop failure occurs if misleading evidence about disease etiology encourages systematic errors that self-perpetuate, compromising future diagnoses and patient care. This article defines scenarios for feedback loop failure in medical diagnosis.

DESIGN

Through simulated cases, we characterize how disease incidence, presentation, and risk factors can be misunderstood when observational data are summarized naive to biases arising from diagnostic error. A fourth simulation extends to a progressive disease.

RESULTS

When severe cases of a disease are diagnosed more readily, less severe cases go undiagnosed, increasingly leading to underestimation of the prevalence and heterogeneity of the disease presentation. Observed differences in incidence and symptoms between demographic groups may be driven by differences in risk, presentation, the diagnostic process itself, or a combination of these. We suggested how perceptions about risk factors and representativeness may drive the likelihood of diagnosis. Differing diagnosis rates between patient groups can feed back to increasingly greater diagnostic errors and disparities in the timing of diagnosis and treatment.

CONCLUSIONS

A feedback loop between past data and future medical practice may seem obviously beneficial. However, under plausible scenarios, poorly implemented feedback loops can degrade care. Direct summaries from observational data based on diagnosed individuals may be misleading, especially concerning those symptoms and risk factors that influence the diagnostic process itself.

HIGHLIGHTS

Current evidence about a disease can (and should) influence the diagnostic process. A feedback loop failure may occur if biased "evidence" encourages diagnostic errors, leading to future errors in the evidence base.When diagnostic accuracy varies for mild versus severe cases or between demographic groups, incorrect conclusions about disease prevalence and presentation will result without specifically accounting for such variability.Use of demographic characteristics in the diagnostic process should be done with careful justification, in particular avoiding potential cognitive biases and overcorrection.

Testing a cognitive behavioural therapy program for anxiety in autistic adolescents: a feasibility study

BACKGROUND

Autism includes core symptoms affecting general and social development. Up to 60% of autistic adolescents experience co-occurring anxiety disorders negatively influencing educational, social, and general development together with quality of life. A manualised cognitive behavioural therapy (CBT) program 'Cool Kids - Autism Spectrum Adaptation (ASA)' has previously demonstrated efficacy in reducing anxiety in children with co-occurring autism. The current study investigates the feasibility of adapting this program for adolescents.

METHODS

Fifteen autistic adolescents, aged 14-17 years, with co-occurring anxiety disorders were enrolled in the study. Outcome measures collected from both adolescents and parents pre-, post-treatment and at 3-month follow-up included participant evaluation of the program, scores from a semi-structured anxiety interview, and questionnaires on anxiety symptoms, life interference, and quality of life.

RESULTS

92% of the families who completed the program found it useful and would recommend it to other families in a similar situation. At follow-up, 55% no longer met the criteria for their primary anxiety diagnosis and 34% of adolescents were free of all anxiety diagnoses. Of the five adolescents who did not attend school before treatment three (60%) had returned to school after treatment.

CONCLUSION

This study suggests that the adaptation of the program 'Cool Kids - ASA' into an adolescent version is feasible and has the potential to show good effects thus enhancing the possibility of education, development and independence in future life for this group. Larger RCTs studies are, however, needed to examine the efficacy of the adolescent version.

Barriers and facilitators to achieving employment in mainstream settings in adults with autism spectrum disorder without intellectual developmental disorders: A scoping review

Autistic people without Intellectual Developmental Disorders (IDD) have a significantly lower employment rate compared to the general population even though employment favors social integration and quality of life.

AIMS

To examine the barriers and facilitators to employability in mainstream settings for autistic adults without intellectual disability.

METHODS

Following the scoping review guidelines, we searched the Cochrane, PubMed and PsycINFO databases for references published between 01/01/2000 to 01/08/2023.

RESULTS

A review of the 44 identified articles suggests the existence of multiple individual and environmental factors influencing job access and retention.

CONCLUSIONS

This is the first review to assess the facilitators and barriers to employment support for autistic people without intellectual disability. The results underline the need for studying strategies to promote access to employment and job retention for autistic people. Future research should explore the mediating and moderating factors leading to the improvement of employability of autistic people WIDD.

Assessing Autism Knowledge Across the Global Landscape Using the ASK-Q

Substantial variability exists with regard to autism service provision around the world. Service disparities observed in many low- and middle-income countries may be driven, in part, by limited autism knowledge; however, measurement limitations have made it difficult to quantify autism knowledge across countries. The current study uses the autism stigma and knowledge questionnaire (ASK-Q) to quantify autism knowledge and stigma between different countries and demographics. The current study compiled data from 6830 participants collected using adapted versions of the ASK-Q administered in 13 different countries, representing four different continents. Structural equation modeling was used to examine how autism knowledge varied across country and individual factors. Results reveal cross country variability with a large, 17-point difference between the countries with the highest knowledge (Canada) and the lowest knowledge (Lebanon). As expected, countries with higher economies had higher levels of knowledge. We also documented differences based on country worldview, participant occupation, gender, age, and education level. These results help to identify specific regions and populations that might most need greater information about autism.

Factors Associated with Confirmed and Unconfirmed Autism Spectrum Disorder Diagnosis in Children Volunteering for Research

PURPOSE

Diagnostic accuracy of autism spectrum disorder (ASD) is crucial to track and characterize ASD, as well as to guide appropriate interventions at the individual level. However, under-diagnosis, over-diagnosis, and misdiagnosis of ASD are still prevalent.

METHODS

We describe 232 children (MAge = 10.71 years; 19% female) with community-based diagnoses of ASD referred for research participation. Extensive assessment procedures were employed to confirm ASD diagnosis before study inclusion. The sample was subsequently divided into two groups with either confirmed ASD diagnoses (ASD+) or unconfirmed/inaccurate diagnoses (ASD-). Clinical characteristics differentiating the groups were further analyzed.

RESULTS

47% of children with community-based ASD diagnoses did not meet ASD criteria by expert consensus. ASD + and ASD- groups did not differ in age, gender, ethnicity, or racial make-up. The ASD + group was more likely to have a history of early language delays compared to the ASD- group; however, no group differences in current functional language use were reported by caregivers. The ASD + group scored significantly higher on ADI-R scores and on the ADOS-2 algorithm composite scores and calibrated severity scores (CSSs). The ASD- group attained higher estimated IQ scores and higher rates of psychiatric disorders, including anxiety disorder, disruptive behavior, and mood disorder diagnoses. Broadly, caregiver questionnaires (SRS-2, CCC-2) did not differentiate groups.

CONCLUSION

Increased reported psychiatric disorders in the ASD- group suggests psychiatric complexity may contribute to community misdiagnosis and possible overdiagnosis of ASD. Clinician-mediated tools (ADI-R, ADOS-2) differentiated ASD + versus ASD- groups, whereas caregiver-reported questionnaires did not.

The Global Burden of Disease Epidemiology-When Big Data Impute the Nonexistent

This Viewpoint discusses concerns about the data quality of the Global Burden of Disease study with respect to incidence estimates of child and adolescent mental health disorders, such as autism and attention-deficit/hyperactivity disorder, in low- and middle-income countries.

The economic burden of autism spectrum disorder with and without intellectual disability in China: A nationwide cost-of-illness study

OBJECTIVE

The economic burden of autism spectrum disorder (ASD) on individuals, their families and society as a whole is poorly understood. Accurate figures are crucial for economic estimates and service planning.

METHODS

The total lifetime individual costs and annual societal costs of ASD in China were estimated with a prevalence-based, gross cost of illness approach and data from multiple sources. The direct medical costs in outpatient and inpatient settings from the electronic health records (EHRs) of hospitals, and direct nonmedical costs from a national survey were included. The indirect costs were from both the national survey and the estimation using human capital methods. Age-specific lifetime incremental societal costs were measured. Comorbidity-related and unrelated costs were analyzed separately.

RESULTS

The discounted lifetime cost for an individual with ASD in China was $2.65 million (at 2020 prices, $) for those without intellectual disability (ID) and $4.61 million (at 2020 prices, $) for those with ID. The total cost of ASD amounted to $41.8 billion in 2020. Productivity loss were major cost drivers for ASD individuals without ID. Direct nonmedical costs (rehabilitation or adult care costs etc.) were major drivers for ASD individuals with ID. In a lifetime course, the total annual costs for middle aged and elderly (>42 years) were highest, followed by transitional adults (18-29 years) and preschoolers, both for individuals with or without ID. The distribution of costs over the lifespan varied by the cost category.

CONCLUSIONS

ASD imposes a substantial economic burden on families and health care systems. Sectors and services coordination should be given policy considerations.

Day-to-day spontaneous social behaviours is quantitatively and qualitatively affected in a 16p11.2 deletion mouse model

Background

Autism spectrum disorders affect more than 1% of the population, impairing social communication and increasing stereotyped behaviours. A micro-deletion of the 16p11.2 BP4-BP5 chromosomic region has been identified in 1% of patients also displaying intellectual disabilities. In mouse models generated to understand the mechanisms of this deletion, learning and memory deficits were pervasive in most genetic backgrounds, while social communication deficits were only detected in some models.

Methods

To complement previous studies, we itemized the social deficits in the mouse model of 16p11.2 deletion on a hybrid C57BL/6N × C3H.Pde6b+ genetic background. We examined whether behavioural deficits were visible over long-term observation periods lasting several days and nights, to parallel everyday-life assessment of patients. We recorded the individual and social behaviours of mice carrying a heterozygous deletion of the homologous 16p11.2 chromosomic region (hereafter Del/+) and their wild-type littermates from both sexes over two or three consecutive nights during social interactions of familiar mixed-genotype quartets of males and of females, and of same-genotype unfamiliar female pairs.

Results

We observed that Del/+ mice of both sexes increased significantly their locomotor activity compared to wild-type littermates. In the social domain, Del/+ mice of both sexes displayed widespread deficits, even more so in males than in females in quartets of familiar individuals. In pairs, significant perturbations of the organisation of the social communication and behaviours appeared in Del/+ females.

Discussion

Altogether, this suggests that, over long recording periods, the phenotype of the 16p11.2 Del/+ mice was differently affected in the locomotor activity and the social domains and between the two sexes. These findings confirm the importance of testing models in long-term conditions to provide a comprehensive view of their phenotype that will refine the study of cellular and molecular mechanisms and complement pre-clinical targeted therapeutic trials.

Cerebral blood flow measured by diffuse correlation spectroscopy in children with autism spectrum disorder

Diffuse correlation spectroscopy (DCS) was used to measure resting-state cerebral blood flow (CBF) in temporal lobes of children with autism spectrum disorder (ASD) and typically developing (TD) children. Twenty-two children with ASD and 34 age-matched TD children were recruited to participate in the experiment. DCS signals were recorded with 3 long source-detector (SD) channels (SD distance = 22.0 mm) and 1 short SD channel (SD distance = 10.5 mm) from each side of the temporal lobe. Significant difference in CBF between left and right hemispheres was observed in ASD group, but not in TD group. With the degree of CBF lateralization as a discrimination feature, a leave-one-out ROC curve was plotted with the area-under-curve (AUC) value of 0.731 ± 0.010, indicating children with ASD could be discriminated from TD children. This suggested CBF lateralization in temporal lobes measured with DCS might serve as a discriminative feature for ASD.

Age and severity-dependent gut microbiota alterations in Tunisian children with autism spectrum disorder

Alterations in gut microbiota and short chain fatty acids (SCFA) have been reported in autism spectrum disorder (ASD). We analysed the gut microbiota and fecal SCFA in Tunisian autistic children from 4 to 10 years, and results were compared to those obtained from a group of siblings (SIB) and children from the general population (GP). ASD patients presented different gut microbiota profiles compared to SIB and GP, with differences in the levels of Bifidobacterium and Collinsella occurring in younger children (4-7 years) and that tend to be attenuated at older ages (8-10 years). The lower abundance of Bifidobacterium is the key feature of the microbiota composition associated with severe autism. ASD patients presented significantly higher levels of propionic and valeric acids than GP at 4-7 years, but these differences disappeared at 8-10 years. To the best of our knowledge, this is the first study on the gut microbiota profile of Tunisian autistic children using a metataxonomic approach. This exploratory study reveals more pronounced gut microbiota alterations at early than at advanced ages in ASD. Although we did not account for multiple testing, our findings suggest that early interventions might mitigate gut disorders and cognitive and neurodevelopment impairment associated to ASD.

Zinc Water Prevents Autism-Like Behaviors in the BTBR Mice

This study aims to explore the effects of zinc water on autism-like behavior, convulsion threshold, and neurogenesis in ASD model animals. This study used the young BTBR ASD mouse model to explore the effect of a 6-week zinc water supplementation on ASD-like behaviors such as repetitive behavior and social communication disorder, seizure threshold, and the correlation with excitability regulation. The mice were divided into four groups of normal controls (B6) and models (BTBR) who did and did not receive zinc supplementation in water (B6, B6 + zinc, BTBR, and BTBR + zinc). For morphological changes in the hippocampus, we selected two indicators: hippocampal mossy fiber sprouting and neurogenesis. ASD-like behavior testing, seizure threshold determination, Timm staining, and neurogenesis-related assays-represented by Ki67 and DCX-were performed after 6 weeks of zinc supplementation. Our results show that zinc water can prevent autism-like behavior, reduce susceptibility to convulsions, and increase the proliferation of hippocampal progenitor cells in BTBR mice but has less effect on mossy fiber sprouting and neural progenitor cell differentiation. Zinc water reduces autism-like behavior in a partially inherited autism model mice-BTBR-which may be associated with hippocampal neural precursor cell proliferation and reversed hyperexcitability.

Can we model autism using zebrafish?

Autism spectrum disorder (ASD) is one of the most common, heritable neuropsychiatric disorders in the world, affecting almost 1% of the population. The core symptoms used to diagnose ASD are decreased social interaction and increased repetitive behaviors. Despite the large number of affected individuals, the precise mechanisms that cause this disorder remain unclear. The identification of genes and environmental factors associated with ASD allows the study of the underlying mechanisms in animal models. Although ASD presents as a human disorder, based on recent advances in understanding their brain anatomy, physiology, behavior, and evolutionary conservation of neuronal cell types, I propose that zebrafish may provide novel insights into the etiology.

High definition transcranial direct current stimulation of the Cz improves social dysfunction in children with autism spectrum disorder: A randomized, sham, controlled study

The purpose of this study was to determine the effect of the Cz of high-definition 5-channel tDCS (HD-tDCS) on social function in 4-12 years-old children with autism spectrum disorder (ASD). This study was a randomized, double-blind, pseudo-controlled trial in which 45 ASD children were recruited and divided into three groups with sex, age, and rehabilitation treatment as control variables. Each group of 15 children with ASD was randomly administered active HD-tDCS with the Cz as the central anode, active HD-tDCS with the left dorsolateral prefrontal cortex (F3) as the central anode, and sham HD-tDCS with the Cz as the central anode with 14 daily sessions in 3 weeks. The Social Responsiveness Scale Chinese Version (SRS-Chinese Version) was compared 1 week after stimulation with values recorded 1 week prior to stimulation. At the end of treatment, both the anodal Cz and anodal left DLFPC tDCS decreased the measures of SRS-Chinese Version. The total score of SRS-Chinese Version decreased by 13.08%, social cognition decreased by 18.33%, and social communication decreased by 10.79%, which were significantly improved over the Cz central anode active stimulation group, especially in children with young age, and middle and low function. There was no significant change in the total score and subscale score of SRS-Chinese Version over the Cz central anode sham stimulation group. In the F3 central anode active stimulation group, the total score of SRS-Chinese Version decreased by 13%, autistic behavior decreased by 19.39%, and social communication decreased by 14.39%, which were all significantly improved. However, there was no significant difference in effect between the Cz and left DLPFC stimulation conditions. HD-tDCS of the Cz central anode may be an effective treatment for social dysfunction in children with ASD.

Consanguinity as a Risk Factor for Autism

PURPOSE

Genetic and environmental risk factors associated with Autism Spectrum Disorders (ASD) continue to be a focus of research worldwide. Consanguinity, the cultural practice of marrying within a family, is common in cultures and societies of the Middle East, North Africa and parts of Asia. Consanguinity has been investigated as a risk factor for ASD in a limited number of studies, with mixed results. We employed registry and survey data from Qatar to evaluate the role of consanguinity as a risk factor for ASD.

METHODS

Data were sourced from a national registry and a population-based survey of autism recently conducted in Qatar. We selected a sample of 891 children (mean age: 8.3 years) with (N = 361) or without (N = 530) ASD. Data on consanguinity and covariates were collected through questionnaires and interviews.

RESULTS

The prevalence of consanguinity in the overall sample was 41.2% with no significant difference between cases and controls (42.1% vs 41.3%; p = .836). In adjusted multiple logistic regression analyses, consanguinity was not associated with risk of ASD (aOR = 1.065; 95% CI: .751-1.509; NS).

CONCLUSION

Parental consanguinity was not associated with autism risk in our study. Replication in other populations with high rates of consanguineous unions is recommended.

Neurological and psychiatric disorders among autistic adults: a population healthcare record study

BACKGROUND

Co-occurring psychiatric disorders are common in autism, with previous studies suggesting 54-94% of autistic individuals develop a mental health condition in their lifetime. Most studies have looked at clinically-recruited cohorts, or paediatric cohorts followed into adulthood, with less known about the autistic community at a population level. We therefore studied the prevalence of co-occurring psychiatric and neurological conditions in autistic individuals in a national sample.

METHODS

This retrospective case-control study utilised the SAIL Databank to examine anonymised whole population electronic health record data from 2001 to 2016 in Wales, UK (N = 3.6 million). We investigated the prevalence of co-occurring psychiatric and selected neurological diagnoses in autistic adults' records during the study period using International Classification of Diseases-10 and Read v2 clinical codes compared to general population controls matched for age, sex and deprivation.

RESULTS

All psychiatric conditions examined were more common amongst adults with autism after adjusting for age, sex and deprivation. Prevalence of attention-deficit hyperactivity disorder (7.00%), bipolar disorder (2.50%), obsessive-compulsive disorder (3.02%), psychosis (18.30%) and schizophrenia (5.20%) were markedly elevated in those with autism, with corresponding odds ratios 8.24-10.74 times the general population. Depression (25.90%) and anxiety (22.40%) were also more prevalent, with epilepsy 9.21 times more common in autism.

CONCLUSIONS

We found that a range of psychiatric conditions were more frequently recorded in autistic individuals. We add to understanding of under-reporting and diagnostic overshadowing in autism. With increasing awareness of autism, services should be cognisant of the psychiatric conditions that frequently co-occur in this population.

Striatal Synaptic Changes and Behavior in Adult mouse Upon Prenatal Exposure to Valproic Acid

Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders characterized by persistent deficits in social communication and social interaction. Altered synaptogenesis and aberrant connectivity responsible for social behavior and communication have been reported in autism pathogenesis. Autism has a strong genetic and heritable component; however, environmental factors including toxins, pesticides, infection and in utero exposure to drugs such as VPA have also been implicated in ASD. Administration of VPA during pregnancy has been used as a rodent model to study pathophysiological mechanisms involved in ASD, and in this study, we used the mouse model of prenatal exposure to VPA to assess the effects on striatal and dorsal hippocampus function in adult mice. Alterations in repetitive behaviors and shift habits were observed in mice prenatally exposed to VPA. In particular, such mice presented a better performance in learned motor skills and cognitive deficits in Y-maze learning frequently associated with striatal and hippocampal function. These behavioral changes were associated with a decreased level of proteins involved in the formation and maintenance of excitatory synapses, such as Nlgn-1 and PSD-95. In conclusion, motor skill abilities, repetitive behaviors, and impaired flexibility to shift habits are associated with reduced striatal excitatory synaptic function in the adult mouse prenatally exposed to VPA.

Toward an integrative socio-cognitive approach in autism spectrum disorder: NEAR method adaptation-study protocol

Background

The cognitive impairments exhibited by people with ASD, threaten the development of social skills that are essential for establishing and maintaining harmonious social relationships. Cognitive remediation and social skills training are now considered as crucial therapeutic approaches in the management of these disorders. Several programs have already been validated and have shown improvements in social skills or cognitive performance. However, the effects of these training methods seem to be difficult to generalize to other everyday life. The aim of our study is to alleviate cognitive and social deficiencies by using a socio-cognitive framework to adapt the Neuropsychological Educational Approach to Remediation (NEAR) method for adolescents with ASD.

Methods/design

Adolescents meeting the DSM-5 criteria for ASD, older than 13 years, and following a regular school curriculum will be recruited from clinical population at the Child and Adolescent Psychiatry in Razi University Hospital-Manouba- Tunisia. Our study is an open and non-randomized controlled trial including 30 patients: NEAR group / control group. The NEAR method combines computerized cognitive exercises and bridging groups inspired from cognitive behavioral therapy. NEAR group will be divided into three groups of five patients each. The duration of the sessions will vary according to the capacities of the participants and the exchanges between them (about 60–120 min). In our study, bridging groups will be amended by adding other tasks including planning role plays and scenarios of problematic social situations in autism, taking into account cultural particularities in order to promote social skills. Computerized exercises will be enriched by adding other tasks aiming to improve the recognition and expression of facial emotions by using digital videos and photographs expressing the six basic emotions. The duration of the program will be about 6 months. All selected patients will have an assessment of cognitive function: social cognition, neurocognition and pragmatic skills, social skills, self-esteem and global functioning at baseline, 1 week after the end of the NEAR program and 6 months later.

Conclusion

This adaptive program is a promising socio-cognitive intervention that create new perspectives for adolescents with autism spectrum disorder.

Sensory Processing and Executive Functioning in Autistic Adults

PURPOSE

One of the core features that can be experienced by adults on the autism spectrum is hyper- and hyporeactivity to sensory stimuli. Research suggests that executive functioning (EF) impairments are related to sensory issues. In this study the relationship between sensory processing issues and EF was investigated. We expected sensory processing issues to predict EF impairments.

METHODS

Thirty men and 30 women on the autism spectrum, 20 men and 24 women without autism were included and matched on intelligence and age. Group comparisons were conducted to determine if groups differed regarding self-reported sensory processing issues (GSQ-NL) and self-reports on EF (BRIEF-A). Correlational and regression analyses were carried out to investigate the relationship between self-reports on GSQ-NL and BRIEF-A.

RESULTS

We found significant differences between men and women on the spectrum with regard to sensory processing issues and EF. Hyporeactivity to sensory information explained most of the EF problems.

CONCLUSION

Clinicians should be aware of differences in sensory experiences between adults on the spectrum and non-autistic adults and differences between men and women during assessment and subsequent counselling.

An Overview on Fecal Profiles of Amino Acids and Related Amino-Derived Compounds in Children with Autism Spectrum Disorder in Tunisia

Autism spectrum disorder (ASD) is a neurodevelopmental pathology characterized by the impairment of social interaction, difficulties in communication, and repetitive behaviors. Alterations in the metabolism of amino acids have been reported. We performed a chromatographic analysis of fecal amino acids, ammonium, biogenic amines, and gamma aminobutyric acid (GABA) in Tunisian autistic children from 4 to 10 years, and results were compared with their siblings (SIB) and children from the general population (GP). ASD presented significantly higher levels of fecal amino acids than SIB and GP; differences being more pronounced in younger (4–7 years) than in older (8–10 years) individuals whereas no changes were found for the remaining compounds. Lower levels of histidine were the only difference related with severe symptoms of autism (CARS scale). A linear discriminant analysis (LDA) based on fecal amino acid profiles clearly separated ASD, SIB, and GP at 4 to 7 years but not at more advanced age (8–10 years), evidencing more pronounced alterations in younger children. The relationship of fecal amino acids with autism needs deeper research integrating blood analytical parameters, brain metabolism, and intestinal microbiota. Fecal amino acids could be targeted for designing personalized diets to prevent or minimize cognitive impairments associated with ASD.

The interaction between intestinal bacterial metabolites and phosphatase and tensin homolog in autism spectrum disorder

Intestinal bacteria-associated para-cresyl sulfate (pCS) and 4-ethylphenyl sulfate (4EPS) are elevated in autism spectrum disorder (ASD). Both metabolites can induce ASD-like behaviors in mice, but the molecular mechanisms are not known. Phosphatase and tensin homolog (PTEN) is a susceptibility gene for ASD. The present study investigated the relation between pCS and 4EPS and PTEN in ASD in a valproic acid (VPA)-induced murine ASD model and an in vitro LPS-activated microglial model. The VPA-induced intestinal inflammation and compromised permeability in the distal ileum was not associated with changes of PTEN expression and phosphorylation. In contrast, VPA reduced PTEN expression in the hippocampus of mice. In vitro results show that pCS and 4EPS reduced PTEN expression and derailed innate immune response of BV2 microglial cells. The PTEN inhibitor VO-OHpic did not affect innate immune response of microglial cells. In conclusion, PTEN does not play a role in intestinal inflammation and compromised permeability in VPA-induced murine model for ASD. Although pCS and 4EPS reduced PTEN expression in microglial cells, PTEN is not involved in the pCS and 4EPS-induced derailed innate immune response of microglial cells. Further studies are needed to investigate the possible involvement of reduced PTEN expression in the ASD brain regarding synapse function and neuronal connectivity.

Resting-state coupling between HbO and Hb measured by fNIRS in autism spectrum disorder

To distinguish between children with autism spectrum disorder (ASD) and typically developing (TD) children, we have uncovered a new discriminative feature, hemoglobin coupling. Functional near-infrared spectroscopy (fNIRS) was used to record resting-state hemodynamic fluctuations in the bilateral temporal lobes in 25 children with ASD and 22 TD children, in which the coupling between low frequency oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (Hb) fluctuations was evaluated by Pearson correlation coefficient. The results showed significantly weak coupling in children with ASD in both the left and right, and throughout the whole temporal cortex. To explain this observation, a simulation study was performed using a balloon model, in which we found four related parameters could impact the coupling. This study suggested that hemoglobin coupling might be applied as a new cerebral hemodynamic characteristic for ASD screening or diagnostics.

Exploring developmental trajectories throughout adolescence of children with autism spectrum disorder without intellectual disability

Characterizing the developmental trajectories of children with autism spectrum disorder (ASD) throughout adolescence and across different domains of functioning offers opportunities to improve long-term outcomes. This prospective study explored, for the first time, the evolution of children with ASD-without intellectual disability (ID) in terms of socio-adaptative skills, learning behaviors, executive functioning (EF), and internalizing/externalizing problems, compared to typically developing (TD) peers. Forty-five children with ASD-without ID and 37 matched TD children (aged 7-11) were assessed at baseline and after 5 years. Parents and teachers completed measures on theory of mind (ToM), socialization, daily living skills, learning style, EF, and emotional/behavioural difficulties at both time points. On all the domains assessed, the ASD group performed significantly worse than the TD group, both in childhood and adolescence. Specific changes were noted between baseline and follow-up assessment on adaptive skills, prosocial behavior, emotional control, inhibit, working memory and monitoring. Group membership (ASD/TD) was influenced by peer relationships and inhibit EF variables. These findings have implications for clinical and school settings.

Prenatal Androgen Exposure and Traits of Autism Spectrum Disorder in the Offspring: Odense Child Cohort

Fetal androgen exposure may be associated with autism spectrum disorder (ASD). We studied 1777 mother-child pairs in the prospective Odense Child Cohort. Prenatal androgen exposure was assessed by maternal 3rd trimester testosterone concentrations, maternal polycystic ovary syndrome (PCOS), and 3 months offspring anogenital distance. ASD traits were assessed at age 3 years with the ASD-symptom scale of the Child Behavior Checklist for ages 1½-5 years. Maternal testosterone was positively associated with traits of ASD in boys (p < 0.05). Maternal PCOS was associated with increased offspring ASD traits (p = 0.046), but became non-significant after excluding parental psychiatric diagnosis. Offspring anogenital distance was not linked to ASD traits. Higher prevalence of ASD in boys could be linked to higher susceptibility to fetal androgen exposure.

Twenty years of discoveries emerging from mouse models of autism

More than 100 single gene mutations and copy number variants convey risk for autism spectrum disorder. To understand the extent to which each mutation contributes to the trajectory of individual symptoms of autism, molecular genetics laboratories have introduced analogous mutations into the genomes of laboratory mice and other species. Over the past twenty years, behavioral neuroscientists discovered the consequences of mutations in many risk genes for autism in animal models, using assays with face validity to the diagnostic and associated behavioral symptoms of people with autism. Identified behavioral phenotypes complement electrophysiological, neuroanatomical, and biochemical outcome measures in mutant mouse models of autism. This review describes the history of phenotyping assays in genetic mouse models, to evaluate social and repetitive behaviors relevant to the primary diagnostic criteria for autism. Robust phenotypes are currently employed in translational investigations to discover effective therapeutic interventions, representing the future direction of an intensely challenging research field.

Does the Potocki-Lupski Syndrome Convey the Autism Spectrum Disorder Phenotype? Case Report and Scoping Review

Potocki-Lupski Syndrome (PTLS) is a rare condition associated with a duplication of 17p11.2 that may underlie a wide range of congenital abnormalities and heterogeneous behavioral phenotypes. Along with developmental delay and intellectual disability, autism-specific traits are often reported to be the most common among patients with PTLS. To contribute to the discussion of the role of autism spectrum disorder (ASD) in the PTLS phenotype, we present a case of a female adolescent with a de novo dup(17) (p11.2p11.2) without ASD features, focusing on in-depth clinical, behavioral, and electrophysiological (EEG) evaluations. Among EEG features, we found the atypical peak-slow wave patterns and a unique saw-like sharp wave of 13 Hz that was not previously described in any other patient. The power spectral density of the resting state EEG was typical in our patient with only the values of non-linear EEG dynamics: Hjorth complexity and fractal dimension were drastically attenuated compared with the patient's neurotypical peers. Here we also summarize results from previously published reports of PTLS that point to the approximately 21% occurrence of ASD in PTLS that might be biased, taking into account methodological limitations. More consistent among PTLS patients were intellectual disability and speech and language disorders.

Social Brain Network of Children with Autism Spectrum Disorder: Characterization of Functional Connectivity and Potential Association with Stereotyped Behavior

Objective: To identify patterns of social dysfunction in adolescents with autism spectrum disorder (ASD), study the potential linkage between social brain networks and stereotyped behavior, and further explore potential targets of non-invasive nerve stimulation to improve social disorders. Methods: Voxel-wise and ROI-wise analysis methods were adopted to explore abnormalities in the functional activity of social-related regions of the brain. Then, we analyzed the relationships between clinical variables and the statistical indicators of social-related brain regions. Results: Compared with the typically developing group, the functional connectivity strength of social-related brain regions with the precentral gyrus, postcentral gyrus, supplementary motor area, paracentral lobule, median cingulum, and paracingulum gyri was significantly weakened in the ASD group (all p < 0. 01). The functional connectivity was negatively correlated with communication, social interaction, communication + social interaction, and the total score of the ADOS scale (r = -0.38, -0.39, -0.40, and -0.3, respectively; all p < 0.01), with social awareness, social cognition, social communication, social motivation, autistic mannerisms, and the total score of the SRS scale (r = -0.32, -0.32, -0.40, -0.30, -0.28, and -0.27, respectively; all p < 0.01), and with the total score of SCQ (r = -0.27, p < 0.01). In addition, significant intergroup differences in clustering coefficients and betweenness centrality were seen across multiple brain regions in the ASD group. Conclusions: The functional connectivity between social-related brain regions and many other brain regions was significantly weakened compared to the typically developing group, and it was negatively correlated with social disorders. Social network dysfunction seems to be related to stereotyped behavior. Therefore, these social-related brain regions may be taken as potential stimulation targets of non-invasive nerve stimulation to improve social dysfunction in children with ASD in the future.

Risk of autism spectrum disorder in offspring with parental schizophrenia: a systematic review and meta-analysis

BACKGROUND

The effect of parental schizophrenia on the risk of Autism Spectrum Disorders (ASD) in offspring has been evaluated in previous studies. However, to our knowledge, no systematic review and meta-analysis have assessed this association. In this study, we aimed to evaluate the risk of ASD in offspring with parental schizophrenia.

METHODS

The electronic databases EMBASE, PubMed, and Scopus were systematically searched. We administered the Newcastle Ottawa quality assessment scale (NOS) to assess the quality of all selected studies. Combined effect values, as well as their 95% confidence intervals (CI), were calculated. We evaluated heterogeneity using Q and I² statistics. The publication bias was evaluated by funnel plot and Egger's regression test. In addition, a leave-one-out sensitivity analysis was performed to assess the robustness of the finding.

RESULTS

A total of 12 observational studies (10 cohorts and two case-control) were included. Our study found a high risk of ASD in offspring exposed to parental schizophrenia [RR = 2.38 (CI%95 2.0-2.83)]. Subgroup and sensitivity analysis confirmed the robustness of our main analysis.

CONCLUSION

The risk of ASD is considerably higher in offspring with parental schizophrenia. Our findings may suggest a shared pathologic pathway between schizophrenia and ASD.

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.

Incidence, prevalence, and global burden of autism spectrum disorder from 1990 to 2019 across 204 countries

Autism spectrum disorder (ASD) substantially contributes to the burden of mental disorders. Improved awareness and changes in diagnostic criteria of ASD may have influenced the diagnostic rates of ASD. However, while data on trends in diagnostic rates in some individual countries have been published, updated estimates of diagnostic rate trends and ASD-related disability at the global level are lacking. Here, we used the Global Burden of Diseases, Injuries, and Risk Factors Study data to address this gap, focusing on changes in prevalence, incidence, and disability-adjusted life years (DALYs) of ASD across the world. From 1990 to 2019, overall age-standardized estimates remained stable globally. Both prevalence and DALYs increased in countries with high socio-demographic index (SDI). However, the age-standardized incidence decreased in some low SDI countries, indicating a need to improve awareness. The male/female ratio decreased between 1990 and 2019, possibly accounted for by increasing clinical attention to ASD in females. Our results suggest that ASD detection in low SDI countries is suboptimal, and that ASD prevention/treatment in countries with high SDI should be improved, considering the increasing prevalence of the disorder. Additionally, growing attention is being paid to ASD diagnosis in females, who might have been left behind by ASD epidemiologic and clinical research previously. ASD burden estimates are underestimated as GBD does not account for mortality in ASD.

Acquisition time for functional near-infrared spectroscopy resting-state functional connectivity in assessing autism

SIGNIFICANCE

Resting state functional connectivity (RSFC) can be used to assess autism spectrum disorder (ASD). Measuring RSFC usually takes 5 to 10 min, during which children with ASD may have difficulty keeping their heads motionless. Therefore, a short acquisition time for RSFC would make clinical implementation more feasible.

AIM

To find a suitable acquisition time necessary for measuring RSFC with functional near-infrared spectroscopy (fNIRS) for the differentiation between children with ASD and typically developing (TD) children.

APPROACH

We used fNIRS to record the spontaneous hemodynamic fluctuations from the bilateral temporal lobes of 25 children with ASD and 22 TD children. The recorded signals were truncated into several segments with different time windows, and then the homotopic RSFC was computed for each of these segments and compared between the two groups.

RESULTS

We observed even in a very short time duration of 0.5 min, the RSFC had already existed a significant difference between the two groups, and 2.0 min might be the minimal time required for measuring RSFC for accurate differentiation between the two groups.

CONCLUSIONS

The fNIRS-RSFC acquired even in a short time, e.g., 2.0 min, might be a reliable feature for the differentiation between children with ASD and TD children.

Thyroid hormones regulate reelin expression in neuropsychiatric disorders

The incidence and prevalence of hypothyroidism in pregnancy have increased over the past two decades, leading to the occurrence of neuropsychiatric disorders. However, the underlying mechanisms of thyroid hormone (TH)-regulated gene expression and neuropsychiatric development during the postnatal period remain unknown. Recent achievements have shown that reelin, a large extracellular glycoprotein, plays a crucial role in neuronal migration and localization during the development of neocortex and cerebellar cortex, thereby participating in the development of neuropsychiatric diseases. Reelin-induced neuronal migration requires triiodothyronine (T3) from the deiodination of thyroxine (T4) by fetal brain deiodinases. Previous studies have reported decreased reelin levels and abnormal gene expression, which are the same as the pathological alternations in reelin-induced neuropsychiatric disorders including schizophrenia and autism. Low T3 in the fetal brain due to hypothyroxinemia during pregnancy may be detrimental to neuronal migration, leading to neuropsychiatric disorders. In this review, we focus on the reelin expression between hypothyroidism and neuropsychiatric disorders.

The Autism Spectrum Disorder-Associated Bacterial Metabolite p-Cresol Derails the Neuroimmune Response of Microglial Cells Partially via Reduction of ADAM17 and ADAM10

The bacterial metabolite 4-methylphenol (para-cresol or p-cresol) and its derivative p-cresyl sulfate (pCS) are elevated in the urine and feces of children with autism spectrum disorder (ASD). It has been shown that p-cresol administration induces social behavior deficits and repetitive behavior in mice. However, the mechanisms of p-cresol, specifically its metabolite pCS that can reach the brain, in ASD remain to be investigated. The pCS has been shown to inhibit LPS-stimulated inflammatory response. A Disintegrin And Metalloprotease 10 (ADAM10) and A Disintegrin And Metalloprotease 17 (ADAM17) are thought to regulate microglial immune response by cleaving membrane-bound proteins. In the present study, a neuroinflammation model of LPS-activated BV2 microglia has been used to unveil the potential molecular mechanism of pCS in ASD pathogenesis. In microglial cells pCS treatment decreases the expression or maturation of ADAM10 and ADAM17. In addition, pCS treatment attenuates TNF-α and IL-6 releases as well as phagocytosis activity of microglia. In in vitro ADAM10/17 inhibition experiments, either ADAM10 or ADAM17 inhibition reduces constitutive and LPS-activated release of TNF-α, TNFR-1 and IL-6R by microglial cells, while it increases constitutive and LPS-activated microglial phagocytotic activity. The in vivo results further confirm the involvement of ADAM10 and ADAM17 in ASD pathogenesis. In in utero VPA-exposed male mice, elevated concentration in serum of p-cresol-associated metabolites pCS and p-cresyl glucuronide (pCG) is associated with a VPA-induced increased ADAM10 maturation, and a decreased ADAM17 maturation that is related with attenuated levels of soluble TNF-α and TGF-β1 in the mice brain. Overall, the present study demonstrates a partial role of ADAM10 and ADAM17 in the derailed innate immune response of microglial cells associated with pCS-induced ASD pathogenesis.

Evidence of increasing recorded diagnosis of autism spectrum disorders in Wales, UK: An e-cohort study

LAY ABSTRACT

Autism spectrum disorders (autism) are thought to be relatively common, with analyses estimating 1% in the population could meet diagnostic criteria. New services for adult diagnosis have been set up in Wales, UK; however, no studies have examined for the proportion of adults with autism in Wales. In this study, we take anonymised healthcare record data from more than 3.6 million people to produce a national estimate of recorded autism diagnoses. We found the overall prevalence rate of autism in healthcare records was 0.51%. The number of new-recorded cases of autism increased from 0.188 per 1000 person-years in 2001 to 0.644 per 1000 person-years in 2016. The estimate of 0.51% prevalence in the population is lower than suggested by population survey and cohort studies, but comparable to other administrative records. From 2001 to 2016, the number of autism services for adults has increased, and autism is more widely known in society, while concurrently in healthcare records, there was a >150% increase autism diagnoses in the years 2008-2016. An increasing number of diagnoses were among women and those aged over 35 years. This study suggests that while the number of people being diagnosed with autism is increasing, many are still unrecognised by healthcare services.

The female protective effect against autism spectrum disorder

Autism spectrum disorder (ASD) is diagnosed three to four times more frequently in males than in females. Genetic studies of rare variants support a female protective effect (FPE) against ASD. However, sex differences in common inherited genetic risk for ASD are less studied, particularly within families. Leveraging the Danish iPSYCH resource, we found siblings of female ASD cases (n = 1,707) had higher rates of ASD than siblings of male ASD cases (n = 6,270; p < 1.0 × 10-10). In the Simons Simplex and SPARK collections, mothers of ASD cases (n = 7,436) carried more polygenic risk for ASD than fathers of ASD cases (n = 5,926; 0.08 polygenic risk score [PRS] SD; p = 7.0 × 10-7). Further, male unaffected siblings under-inherited polygenic risk (n = 1,519; p = 0.03). Using both epidemiologic and genetic approaches, our findings strongly support an FPE against ASD's common inherited influences.

Specialised minds: extending adaptive explanations of personality to the evolution of psychopathology

Traditional evolutionary theory invoked natural and sexual selection to explain species- and sex-typical traits. However, some heritable inter-individual variability in behaviour and psychology - personality - is probably adaptive. Here we extend this insight to common psychopathological traits. Reviewing key findings from three background areas of importance - theoretical models, non-human personality and evolved human social dynamics - we propose that a combination of social niche specialisation, negative frequency-dependency, balancing selection and adaptive developmental plasticity should explain adaptation for individual differences in psychology - 'specialised minds' - explaining some variance in personality and psychopathology trait dimensions, which share various characteristics. We suggest that anthropological research of behavioural differences should be extended past broad demographic factors (age and sex) to include individual specialisations. As a first step towards grounding psychopathology in ancestral social structure, we propose a minimum plausible prevalence, given likely ancestral group sizes, for negatively frequency-dependent phenotypes to be maintained as specialised tails of adaptive distributions - below the calculated prevalence, specialisation is highly unlikely. For instance, chronic highly debilitating forms of autism or schizophrenia are too rare for such explanations, whereas attention-deficit-hyperactivity disorder and broad autism phenotypes are common enough to have existed in most hunter-gatherer bands, making adaptive explanations more plausible.

Risk factors for ASD : Risk Factors for Autism Spectrum Disorder in Shanghai, China: A Population-based Case-control Study

Autism spectrum disorder (ASD) is a pervasive neurodevelopmental disorder that brings heavy burdens to families and the society. This case-control study explored risk factors for ASD based on 74,252 children aged 3-12 years who were recruited from general education kindergartens, primary schools, and special education schools in Shanghai, China. One hundred ninety-two children were identified with ASD according to the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition. Male sex, the presence of anoxia or asphyxia at birth, artificial feeding, adverse maternal psychological status, complications during pregnancy and higher paternal education were associated with ASD even after controlling for age, residential district, family history of mental disorders, parental personality, and amount of daily TV viewing.

Global, regional and national burden of autism spectrum disorder from 1990 to 2019: results from the Global Burden of Disease Study 2019

AIMS

Autism spectrum disorder (ASD) is a neurodevelopmental condition, with symptoms appearing in the early developmental period. Little is known about its current burden at the global, regional and national levels. This systematic analysis aims to summarise the latest magnitudes and temporal trends of ASD burden, which is essential to facilitate more detailed development of prevention and intervention strategies.

METHODS

The data on ASD incidence, prevalence, disability-adjusted life years (DALYs) in 204 countries and territories between 1990 and 2019 came from the Global Burden of Disease Study 2019. The average annual percentage change was calculated to quantify the secular trends in age-standardised rates (ASRs) of ASD burden by region, sex and age.

RESULTS

In 2019, there were an estimated 60.38 × 104 [95% uncertainty interval (UI) 50.17-72.01] incident cases of ASD, 283.25 × 105 (95% UI 235.01-338.11) prevalent cases and 43.07 × 105 (95% UI 28.22-62.32) DALYs globally. The ASR of incidence slightly increased by around 0.06% annually over the past three decades, while the ASRs of prevalence and DALYs both remained stable over the past three decades. In 2019, the highest burden of ASD was observed in high-income regions, especially in high-income North America, high-income Asia Pacific and Western Europe, where a significant growth in ASRs was also observed. The ASR of ASD burden in males was around three times that of females, but the gender difference was shrunk with the pronounced increase among females. Of note, among the population aged over 65 years, the burden of ASD presented increasing trends globally.

CONCLUSIONS

The global burden of ASD continues to increase and remains a major mental health concern. These substantial heterogeneities in ASD burden worldwide highlight the need for making suitable mental-related policies and providing special social and health services.

TAU ablation in excitatory neurons and postnatal TAU knockdown reduce epilepsy, SUDEP, and autism behaviors in a Dravet syndrome model

Intracellular accumulation of TAU aggregates is a hallmark of several neurodegenerative diseases. However, global genetic reduction of TAU is beneficial also in models of other brain disorders that lack such TAU pathology, suggesting a pathogenic role of nonaggregated TAU. Here, conditional ablation of TAU in excitatory, but not inhibitory, neurons reduced epilepsy, sudden unexpected death in epilepsy, overactivation of the phosphoinositide 3-kinase-AKT-mammalian target of rapamycin pathway, brain overgrowth (megalencephaly), and autism-like behaviors in a mouse model of Dravet syndrome, a severe epileptic encephalopathy of early childhood. Furthermore, treatment with a TAU-lowering antisense oligonucleotide, initiated on postnatal day 10, had similar therapeutic effects in this mouse model. Our findings suggest that excitatory neurons are the critical cell type in which TAU has to be reduced to counteract brain dysfunctions associated with Dravet syndrome and that overall cerebral TAU reduction could have similar benefits, even when initiated postnatally.

Combining voice and language features improves automated autism detection

Variability in expressive and receptive language, difficulty with pragmatic language, and prosodic difficulties are all features of autism spectrum disorder (ASD). Quantifying language and voice characteristics is an important step for measuring outcomes for autistic people, yet clinical measurement is cumbersome and costly. Using natural language processing (NLP) methods and a harmonic model of speech, we analyzed language transcripts and audio recordings to automatically classify individuals as ASD or non-ASD. One-hundred fifty-eight participants (88 ASD, 70 non-ASD) ages 7 to 17 were evaluated with the autism diagnostic observation schedule (ADOS-2), module 3. The ADOS-2 was transcribed following modified SALT guidelines. Seven automated language measures (ALMs) and 10 automated voice measures (AVMs) for each participant were generated from the transcripts and audio of one ADOS-2 task. The measures were analyzed using support vector machine (SVM; a binary classifier) and receiver operating characteristic (ROC). The AVM model resulted in an ROC area under the curve (AUC) of 0.7800, the ALM model an AUC of 0.8748, and the combined model a significantly improved AUC of 0.9205. The ALM model better detected ASD participants who were younger and had lower language skills and shorter activity time. ASD participants detected by the AVM model had better language profiles than those detected by the language model. In combination, automated measurement of language and voice characteristics successfully differentiated children with and without autism. This methodology could help design robust outcome measures for future research. LAY SUMMARY: People with autism often struggle with communication differences which traditional clinical measures and language tests cannot fully capture. Using language transcripts and audio recordings from 158 children ages 7 to 17, we showed that automated, objective language and voice measurements successfully predict the child's diagnosis. This methodology could help design improved outcome measures for research.