Environmental risk factors and biomarkers for autism spectrum disorder: an umbrella review of the evidence

Protocol for the development of a reporting guideline for umbrella reviews on epidemiological associations using cross-sectional, case-control and cohort studies: the Preferred Reporting Items for Umbrella Reviews of Cross-sectional, Case-control and Cohort studies (PRIUR-CCC)

INTRODUCTION

Observational studies are fraught with several biases including reverse causation and residual confounding. Overview of reviews of observational studies (ie, umbrella reviews) synthesise systematic reviews with or without meta-analyses of cross-sectional, case-control and cohort studies, and may also aid in the grading of the credibility of reported associations. The number of published umbrella reviews has been increasing. Recently, a reporting guideline for overviews of reviews of healthcare interventions (Preferred Reporting Items for Overviews of Reviews (PRIOR)) was published, but the field lacks reporting guidelines for umbrella reviews of observational studies. Our aim is to develop a reporting guideline for umbrella reviews on cross-sectional, case-control and cohort studies assessing epidemiological associations.

METHODS AND ANALYSIS

We will adhere to established guidance and prepare a PRIOR extension for systematic reviews of cross-sectional, case-control and cohort studies testing epidemiological associations between an exposure and an outcome, namely Preferred Reporting Items for Umbrella Reviews of Cross-sectional, Case-control and Cohort studies (PRIUR-CCC). Step 1 will be the project launch to identify stakeholders. Step 2 will be a literature review of available guidance to conduct umbrella reviews. Step 3 will be an online Delphi study sampling 100 participants among authors and editors of umbrella reviews. Step 4 will encompass the finalisation of PRIUR-CCC statement, including a checklist, a flow diagram, explanation and elaboration document. Deliverables will be (i) identifying stakeholders to involve according to relevant expertise and end-user groups, with an equity, diversity and inclusion lens; (ii) completing a narrative review of methodological guidance on how to conduct umbrella reviews, a narrative review of methodology and reporting in published umbrella reviews and preparing an initial PRIUR-CCC checklist for Delphi study round 1; (iii) preparing a PRIUR-CCC checklist with guidance after Delphi study; (iv) publishing and disseminating PRIUR-CCC statement.

ETHICS AND DISSEMINATION

PRIUR-CCC has been approved by The Ottawa Health Science Network Research Ethics Board and has obtained consent (20220639-01H). Participants to step 3 will give informed consent. PRIUR-CCC steps will be published in a peer-reviewed journal and will guide reporting of umbrella reviews on epidemiological associations.

Predicting autism spectrum disorder using maternal risk factors: A multi-center machine learning study

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a complex environmental etiology involving maternal risk factors, which have been combined with machine learning to predict ASD. However, limited studies have considered the factors throughout preconception, perinatal, and postnatal periods, and even fewer have been conducted in multi-center. In this study, five predictive models were developed using 57 maternal risk factors from a cohort across ten cities (ASD:1232, typically developing[TD]: 1090). The extreme gradient boosting model performed best, achieving an accuracy of 66.2 % on the external cohort from three cities (ASD:266, TD:353). The most important risk factors were identified as unstable emotions and lack of multivitamin supplementation using Shapley values. ASD risk scores were calculated based on predicted probabilities from the optimal model and divided into low, medium, and high-risk groups. The logistic analysis indicated that the high-risk group had a significantly increased risk of ASD compared to the low-risk group. Our study demonstrated the potential of machine learning models in predicting the risk for ASD based on maternal factors. The developed model provided insights into the maternal emotion and nutrition factors associated with ASD and highlighted the potential clinical applicability of the developed model in identifying high-risk populations.

Neurodevelopmental Disruptions in Children of Preeclamptic Mothers: Pathophysiological Mechanisms and Consequences

Preeclampsia (PE) is a multisystem disorder characterized by elevated blood pressure in the mother, typically occurring after 20 weeks of gestation and posing risks to both maternal and fetal health. PE causes placental changes that can affect the fetus, particularly neurodevelopment. Its key pathophysiological mechanisms encompass hypoxia, vascular and angiogenic dysregulation, inflammation, neuronal and glial alterations, and disruptions in neuronal signaling. Animal models indicate that PE is correlated with neurodevelopmental alterations and cognitive dysfunctions in offspring and in humans, an association between PE and conditions such as cerebral palsy, autism spectrum disorder, attention deficit hyperactivity disorder, and sexual dimorphism has been observed. Considering the relevance for mothers and children, we conducted a narrative literature review to describe the relationships between the pathophysiological mechanisms behind neurodevelopmental alterations in the offspring of PE mothers, along with their potential consequences. Furthermore, we emphasize aspects pertinent to the prevention/treatment of PE in pregnant mothers and alterations observed in their offspring. The present narrative review offers a current, complete, and exhaustive analysis of (i) the pathophysiological mechanisms that can affect neurodevelopment in the children of PE mothers, (ii) the relationship between PE and neurological alterations in offspring, and (iii) the prevention/treatment of PE.

Environmental Risk Factors, Protective Factors, and Biomarkers for Hearing Loss: An Umbrella Review

OBJECTIVE

We aimed to investigate the potential environmental risk factors, protective factors, and biomarkers of hearing loss (HL), and establish a hierarchy of evidence.

DATA SOURCES

Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to June 1, 2023.

REVIEW METHODS

We included meta-analyses of observational studies of associations between HL and environmental risk factors, protective factors, or biomarkers. We calculated summary effect estimates, 95% confidence interval, heterogeneity I2 statistic, 95% prediction interval, small study effects, and excess significance biases.

RESULTS

Of the 9211 articles retrieved, 60 eligible articles were included. The 60 eligible articles identified 47 potential environmental risk and protective factors (N = 4,123,803) and 46 potential biomarkers (N = 173,701). Evidence of association was convincing (class I) for rheumatoid arthritis (RA) and every 1 cm increase in height. Evidence of association was highly suggestive (class II) for human immunodeficiency virus (HIV), diabetes, cumulative noise exposure (CNE), smoking, congenital cytomegalovirus (CMV) infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and alopecia areata (AA).

CONCLUSION

In this umbrella review, RA, every 1 cm increase in height, HIV, diabetes, CNE, smoking, congenital CMV infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and AA were strongly associated with HL.

The spectrum of pre-mRNA splicing in autism

Disruptions in spatiotemporal gene expression can result in atypical brain function. Specifically, autism spectrum disorder (ASD) is characterized by abnormalities in pre-mRNA splicing. Abnormal splicing patterns have been identified in the brains of individuals with ASD, and mutations in splicing factors have been found to contribute to neurodevelopmental delays associated with ASD. Here we review studies that shed light on the importance of splicing observed in ASD and that explored the intricate relationship between splicing factors and ASD, revealing how disruptions in pre-mRNA splicing may underlie ASD pathogenesis. We provide an overview of the research regarding all splicing factors associated with ASD and place a special emphasis on five specific splicing factors-HNRNPH2, NOVA2, WBP4, SRRM2, and RBFOX1-known to impact the splicing of ASD-related genes. In the discussion of the molecular mechanisms influenced by these splicing factors, we lay the groundwork for a deeper understanding of ASD's complex etiology. Finally, we discuss the potential benefit of unraveling the connection between splicing and ASD for the development of more precise diagnostic tools and targeted therapeutic interventions. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Evolution and Genomics > Computational Analyses of RNA RNA-Based Catalysis > RNA Catalysis in Splicing and Translation.

Association between interpregnancy interval and risk of autism spectrum disorder: a systematic review and Bayesian network meta-analysis

Although the risk of autism spectrum disorder (ASD) has been reported to be associated with interpregnancy intervals (IPIs), their association remains debatable due to inconsistent findings in existing studies. Therefore, the present study aimed to explore their association. PubMed, Embase, Web of Science, and the Cochrane Library were systematically retrieved up to May 25, 2022. An updated search was performed on May 25, 2023, to encompass recent studies. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). Our primary outcome measures were expressed as adjusted odds ratios (ORs). Given various control measures for IPI and diverse IPI thresholds in the included studies, a Bayesian network meta-analysis was performed. Eight studies were included, involving 24,865 children with ASD and 2,890,289 children without ASD. Compared to an IPI of 24 to 35 months, various IPIs were significantly associated with a higher risk of ASD (IPIs < 6 months: OR = 1.63, 95% CI 1.53-1.74, n = 5; IPIs of 6-11 months: OR = 1.50, 95% CI 1.42-1.59, n = 4; IPIs of 12-23 months: OR = 1.19, 95% CI 1.12-1.23, n = 10; IPIs of 36-59 months: OR = 0.96, 95% CI 0.94-0.99, n = 2; IPIs of 60-119 months: OR = 1.15, 95% CI 1.10-1.20, n = 4; IPIs > 120 months: OR = 1.57, 95% CI 1.43-1.72, n = 4). After adjusting confounding variables, our analysis delineated a U-shaped restricted cubic spline curve, underscoring that both substantially short (< 24 months) and excessively long IPIs (> 72 months) are significantly correlated with an increased risk of ASD.  Conclusion: Our analysis indicates that both shorter and longer IPIs might predispose children to a higher risk of ASD. Optimal childbearing health and neurodevelopmental outcomes appear to be associated with a moderate IPI, specifically between 36 and 60 months. What is Known: • An association between autism spectrum disorder (ASD) and interpregnancy intervals (IPIs) has been speculated in some reports. • This association remains debatable due to inconsistent findings in available studies. What is New: • Our study delineated a U-shaped restricted cubic spline curve, suggesting that both shorter and longer IPIs predispose children to a higher risk of ASD. • Optimal childbearing health and neurodevelopmental outcomes appear to be associated with a moderate IPI, specifically between 36 and 60 months.

Management of Pregnant Women with Mental Disorders Requires Attention to Gestational Diabetes Mellitus

Background

Psychiatric interventions may be required during pregnancy. In the aspect of the management of psychiatric symptoms and the consideration of the need for pharmacotherapy, possibly to manage the effects on the fetus, pregnant women with mental disorders are considered high risk as other physical illnesses.

Objective

We investigated the characteristics of pregnant women with psychiatric disorders compared with high-risk pregnant women with physical illnesses at our university hospital and the effects of psychotropic drug use on pregnant women with mental disorders and their children.

Materials and Methods

In a multivariate analysis of 1282 pregnant women, excluding those with multiple pregnancies who gave birth at our hospital between January 2017 and the end of December 2019, we evaluated the effects of mental disorders and the use of psychotropic drugs throughout at least the third trimester up to the day of delivery on obstetric complications and infants. All data were collected retrospectively.

Results

Ninety-nine pregnant women had mental disorders and 62 took psychotropic drugs. Among multiple factors, pregnant women with mental disorders were associated with significantly higher rates of smoking and gestational diabetes mellitus (GDM) and significantly lower child abnormalities. The cause or effect was difficult to determine; however, the use of antipsychotics or antidepressants was also significantly associated with GDM, while psychotropic use was not related to any of the other factors investigated in this study.

Conclusions

Attention to GDM might be important in the management of pregnant women with mental disorders.

Percutaneous vertebroplasty versus percutaneous kyphoplasty for osteoporotic vertebral compression fractures: an umbrella review protocol of systematic reviews and meta-analyses

INTRODUCTION

Several systematic reviews and meta-analyses have confirmed that percutaneous vertebroplasty and percutaneous kyphoplasty showed safety and beneficial efficacy in patients with osteoporotic vertebral compression fractures. Whereas, there is wide variation among results, which are not conducive to the evaluation and use of clinicians. This study will investigate the efficacy and safety of percutaneous vertebroplasty and percutaneous kyphoplasty for the treatment of osteoporotic vertebral compression fractures, aiming to provide a more reliable evidence base for clinical practice in treating osteoporotic vertebral compression fractures.

METHODS AND ANALYSIS

We will retrieve the relevant articles using the five databases(PubMed, Scopus, EMBASE, Cochrane Library and Web of Science) from inception to March 2023 for systematic review and meta-analysis comparing the overall safety and efficacy of percutaneous vertebroplasty and percutaneous kyphoplasty in patients with osteoporotic vertebral compression fractures. Three reviewers will screen citation titles, abstracts and evaluate the full text of each relevant citation based on prespecified eligibility criteria. Any discrepancies in decisions between reviewers will be resolved through discussion. We will assess the methodological quality of the included studies according to A MeaSurement Tool to Assess systematic Reviews 2 checklist.

ETHICS AND DISSEMINATION

This umbrella review will inform clinical and policy decisions regarding the benefits and harms of percutaneous vertebroplasty versus percutaneous kyphoplasty for osteoporotic vertebral compression fractures. Neither primary data nor individual patient information will be collected, thus ethics approval is not required. Findings will be reported through a peer-reviewed publication, conference presentations and the popular press.

PROSPERO REGISTRATION NUMBER

CRD42021268141.

Development and validation of a risk score model for predicting autism based on pre- and perinatal factors

Background

The use of pre- and perinatal risk factors as predictive factors may lower the age limit for reliable autism prediction. The objective of this study was to develop a clinical model based on these risk factors to predict autism.

Methods

A stepwise logistic regression analysis was conducted to explore the relationships between 28 candidate risk factors and autism risk among 615 Han Chinese children with autism and 615 unrelated typically developing children. The significant factors were subsequently used to create a clinical risk score model. A chi-square automatic interaction detector (CHAID) decision tree was used to validate the selected predictors included in the model. The predictive performance of the model was evaluated by an independent cohort.

Results

Five factors (pregnancy influenza-like illness, pregnancy stressors, maternal allergic/autoimmune disease, cesarean section, and hypoxia) were found to be significantly associated with autism risk. A receiver operating characteristic (ROC) curve indicated that the risk score model had good discrimination ability for autism, with an area under the curve (AUC) of 0.711 (95% CI=0.679-0.744); in the external validation cohort, the model showed slightly worse but overall similar predictive performance. Further subgroup analysis indicated that a higher risk score was associated with more behavioral problems. The risk score also exhibited robustness in a subgroup analysis of patients with mild autism.

Conclusion

This risk score model could lower the age limit for autism prediction with good discrimination performance, and it has unique advantages in clinical application.

Serotonin modulates excitatory synapse maturation in the developing prefrontal cortex

Serotonin (5-HT) imbalances in the developing prefrontal cortex (PFC) are linked to long-term behavioral deficits. However, the synaptic mechanisms underlying 5-HT-mediated PFC development are unknown. We found that chemogenetic suppression and enhancement of 5-HT release in the PFC during the first two postnatal weeks decreased and increased the density and strength of excitatory spine synapses, respectively, on prefrontal layer 2/3 pyramidal neurons in mice. 5-HT release on single spines induced structural and functional long-term potentiation (LTP), requiring both 5-HT2A and 5-HT7 receptor signals, in a glutamatergic activity-independent manner. Notably, LTP-inducing 5-HT stimuli increased the long-term survival of newly formed spines ( ≥ 6 h) via 5-HT7 Gαs activation. Chronic treatment of mice with fluoxetine, a selective serotonin-reuptake inhibitor, during the first two weeks, but not the third week of postnatal development, increased the density and strength of excitatory synapses. The effect of fluoxetine on PFC synaptic alterations in vivo was abolished by 5-HT2A and 5-HT7 receptor antagonists. Our data describe a molecular basis of 5-HT-dependent excitatory synaptic plasticity at the level of single spines in the PFC during early postnatal development.

Severity of Autism Spectrum Disorder Symptoms Associated with de novo Variants and Pregnancy-Induced Hypertension

Genetic factors, particularly, de novo variants (DNV), and an environment factor, exposure to pregnancy-induced hypertension (PIH), were reported to be associated with risk of autism spectrum disorder (ASD); however, how they jointly affect the severity of ASD symptom is unclear. We assessed the severity of core ASD symptoms affected by functional de novo variants or PIH. We selected phenotype data from Simon's Simplex Collection database, used genotypes from previous studies, and created linear regression models. We found that ASD patients carrying DNV with PIH exposure had increased adaptive and cognitive ability, decreased social problems, and enhanced repetitive behaviors; however, there was no difference in patients without DNV between those with or without PIH exposure. In addition, the DNV genes carried by patients exposed to PIH were enriched in ubiquitin-dependent proteolytic processes, highlighting how candidate genes in pathways and environments interact. The results indicate the joint contribution of DNV and PIH to ASD.

Relationship between autism and brain cortex surface area: genetic correlation and a two-sample Mendelian randomization study

BACKGROUND

Alterations in surface area (SA) in specific regions of the cortex have been reported in many individuals with autism spectrum disorder (ASD), however, the genetic background between ASD and SA is still unclear. This study estimated the genetic correlation and causal effect of ASD and cortical SA.

METHODS

Summarized data of genome-wide association studies (GWAS) were separately downloaded from the Psychiatric Genomics Consortium (18,381 cases of ASD, and 27,969 controls) and the Enhancing Neuroimaging Genetics through Meta-Analysis Consortium (33,992 participants of Europeans). We used Linkage disequilibrium score regression (LDSC) and Heritability Estimation from Summary Statistics (HESS) to calculate the heritability of each trait. As for the genetic correlation between ASD and SA, LDSC was used for global correlation and HESS was used to examine the local genetic covariance further. We used three Mendelian randomization (MR) methods, Inverse-variance weighted, MR-Egger, and weighted median to estimate the causal relationship.

RESULTS

LDSC observed a nominal significant genetic correlation (rg = 0.1229, P-value = 0.0346) between ASD and SA of the rostral anterior cingulate gyrus whereas analysis through HESS did not reveal any significant loci having genetic covariance. Based on MR results, statistically meaningful estimations were found in the following areas, postcentral cortex (β (SE) = 21.82 (7.84) mm, 95% CI: 6.46 to 37.19 mm, PIVW = 5.38 × 10- 3, PFDR = 3.09 × 10- 2), posterior cingulate gyrus (β (SE) = 6.23 (2.69) mm, 95% CI: 0.96 to 11.49 mm, PIVW = 2.05 × 10- 2, PFDR = 4.26 × 10- 2), supramarginal gyrus (β (SE) = 19.25 (8.43) mm, 95% CI: 29.29 to 35.77 mm, PIVW = 2.24 × 10- 2, PFDR = 4.31 × 10- 2).

CONCLUSION

Our results provided genetic evidence to support the opinion that individuals with ASD tend to develop differences in cortical SA of special areas. The findings contributed to understanding the genetic relationship between ASD and cortical SA.

Reanalysis of Trio Whole-Genome Sequencing Data Doubles the Yield in Autism Spectrum Disorder: De Novo Variants Present in Half

Autism spectrum disorder (ASD) is a common condition with lifelong implications. The last decade has seen dramatic improvements in DNA sequencing and related bioinformatics and databases. We analyzed the raw DNA sequencing files on the Variantyx® bioinformatics platform for the last 50 ASD patients evaluated with trio whole-genome sequencing (trio-WGS). "Qualified" variants were defined as coding, rare, and evolutionarily conserved. Primary Diagnostic Variants (PDV), additionally, were present in genes directly linked to ASD and matched clinical correlation. A PDV was identified in 34/50 (68%) of cases, including 25 (50%) cases with heterozygous de novo and 10 (20%) with inherited variants. De novo variants in genes directly associated with ASD were far more likely to be Qualifying than non-Qualifying versus a control group of genes (p = 0.0002), validating that most are indeed disease related. Sequence reanalysis increased diagnostic yield from 28% to 68%, mostly through inclusion of de novo PDVs in genes not yet reported as ASD associated. Thirty-three subjects (66%) had treatment recommendation(s) based on DNA analyses. Our results demonstrate a high yield of trio-WGS for revealing molecular diagnoses in ASD, which is greatly enhanced by reanalyzing DNA sequencing files. In contrast to previous reports, de novo variants dominate the findings, mostly representing novel conditions. This has implications to the cause and rising prevalence of autism.

Examining associations of folic acid supplements administered to mothers during pre-conceptional and prenatal periods with autism spectrum disorders in their offspring: insights from a multi-center study in China

Objective

To investigate the relationship between maternal folic acid (FA) supplementation during the pre-conceptional and prenatal periods and the subsequent risk of autism spectrum disorder (ASD) in offspring.

Methods

A total of 6,049 toddlers aged 16-30 months were recruited from August 2016 to March 2017 for this cross-sectional study conducted in China. The parents of the enrolled toddlers provided information on maternal supplemental FA, socio-demographic information, and related covariates. Standard diagnostic procedures were implemented to identify toddlers with ASD.

Results

Among the 6,049 children included in the study, consisting of 3,364 boys with an average age of 22.7 ± 4.1 months, a total of 71 children (1.2%) were diagnosed with ASD. Mothers who did not consume FA supplements during the prenatal period were found to have a significantly increased risk of having offspring with ASD, in comparison to those who were exposed to FA supplements (odds ratio [OR] = 2.47). However, we did not find a similar association during the pre-conceptional period. Compared to mothers who consistently used FA supplements from pre-conception to the prenatal period, those who never used FA supplements were statistically significantly associated with a higher risk of ASD in their offspring (OR = 2.88).

Conclusion

This study indicated that providing continuous maternal FA supplementation during the pre-conceptional and prenatal periods may decrease the risk of ASD in offspring. The prenatal period is considered to be the most crucial time for intervention.

A comparison between children and adolescents with autism spectrum disorders and healthy controls in biomedical factors, trace elements, and microbiota biomarkers: a meta-analysis

Introduction

Autism spectrum disorder (ASD) is a multifaceted developmental condition that commonly appears during early childhood. The etiology of ASD remains multifactorial and not yet fully understood. The identification of biomarkers may provide insights into the underlying mechanisms and pathophysiology of the disorder. The present study aimed to explore the causes of ASD by investigating the key biomedical markers, trace elements, and microbiota factors between children with autism spectrum disorder (ASD) and control subjects.

Methods

Medline, PubMed, ProQuest, EMBASE, Cochrane Library, PsycINFO, Web of Science, and EMBSCO databases have been searched for publications from 2012 to 2023 with no language restrictions using the population, intervention, control, and outcome (PICO) approach. Keywords including "autism spectrum disorder," "oxytocin," "GABA," "Serotonin," "CRP," "IL-6," "Fe," "Zn," "Cu," and "gut microbiota" were used for the search. The Joanna Briggs Institute (JBI) critical appraisal checklist was used to assess the article quality, and a random model was used to assess the mean difference and standardized difference between ASD and the control group in all biomedical markers, trace elements, and microbiota factors.

Results

From 76,217 records, 43 studies met the inclusion and exclusion criteria and were included in this meta-analysis. The pooled analyses showed that children with ASD had significantly lower levels of oxytocin (mean differences, MD = -45.691, 95% confidence interval, CI: -61.667, -29.717), iron (MD = -3.203, 95% CI: -4.891, -1.514), and zinc (MD = -6.707, 95% CI: -12.691, -0.722), lower relative abundance of Bifidobacterium (MD = -1.321, 95% CI: -2.403, -0.238) and Parabacteroides (MD = -0.081, 95% CI: -0.148, -0.013), higher levels of c-reactive protein, CRP (MD = 0.401, 95% CI: 0.036, 0.772), and GABA (MD = 0.115, 95% CI: 0.045, 0.186), and higher relative abundance of Bacteroides (MD = 1.386, 95% CI: 0.717, 2.055) and Clostridium (MD = 0.281, 95% CI: 0.035, 0.526) when compared with controls. The results of the overall analyses were stable after performing the sensitivity analyses. Additionally, no substantial publication bias was observed among the studies.

Interpretation

Children with ASD have significantly higher levels of CRP and GABA, lower levels of oxytocin, iron, and zinc, lower relative abundance of Bifidobacterium and Parabacteroides, and higher relative abundance of Faecalibacterium, Bacteroides, and Clostridium when compared with controls. These results suggest that these indicators may be a potential biomarker panel for the diagnosis or determining therapeutic targets of ASD. Furthermore, large, sample-based, and randomized controlled trials are needed to confirm these results.

Exposure to greenness during pregnancy and the first three years after birth and autism spectrum disorder: A matched case-control study in shanghai, China

Causes of autism spectrum disorder (ASD) have not been fully understood. Previous studies have linked environmental factors with ASD. However, evidence for the greenness-ASD association is limited, especially in China. To fill this gap, we conducted a matched case-control study to examine the association between greenness and ASD in China. Participants in this study were 84,934 children aged 3-12 years in Shanghai, China, selected using a multi-stage cluster sampling method. ASD cases were firstly screened by questionnaires completed by both children's parents and teachers, and were then confirmed by clinical examinations. Further, 10 healthy controls were randomly selected to match each ASD case by age and sex. The final analyses included 146 ASD cases and 1460 healthy controls. Participants' exposure to greenness before and after birth was assessed by normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) from NASA's Earth Observing System according to their residential locations. We used conditional logistic regression to examine the ASD-greenness association. Per interquartile range (IQR) increase in EVI500m and NDVI500m during the year before birth were associated with lower risks of ASD with adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of 0.96 (95%CI: 0.946, 0.975, IQR = 0.074) and 0.937 (95%CI: 0.915, 0.959, IQR = 0.101). Exposure to greenness during the first 3 years after birth was also significantly associated with lower risk of ASD [IQR ORs for EVI500m and NDVI500m were 0.935 (95%CI: 0.91, 0.962, IQR = 0.06) and 0.897 (95%CI: 0.861, 0.935, IQR = 0.09), respectively]. Air pollution showed mediation effects on thegreenness-ASD association. Greenness was observed to have stronger beneficial effects on children without historical diseases and term birth. More greenness exposure before and after birth were significantly associated with lower risks of ASD in children. Our results highlight the importance of greenness in urban planning.

Associations of unintended pregnancy with autism spectrum disorders and the modification of folic acid supplements

There is limited evidence on the associations of unintended pregnancy with autism spectrum disorders (ASD). This study aimed to examine this relationship and the modification of pre-conceptional and prenatal folic acid supplements. Six thousand and five toddlers aged 16 to 30 months from seven cities of six provinces in China were eligible for participation. Information on unintended pregnancy and folic acid supplements was obtained via questionnaires from caregivers of toddlers. The diagnosis of ASD was based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) and the Chinese version of the Childhood Autism Rating Scale (CARS). Of the 6005 toddlers in the study (3337 boys and 2668 girls), 71 (1.18%) received the diagnosis of ASD. Generalized linear models with a logit link function showed unintended pregnancy was positively associated with ASD (odds ratios [OR] = 1.69, 95% confidence interval [CI], 1.05-2.79). Stratified estimates indicated that the association remained stable among toddlers of mothers without pre-conceptional and prenatal folic acid supplements (OR = 2.75, 95% CI, 1.04-7.27; n = 1243, 20.70%). Unintended pregnancy was associated with higher odds of ASD in 16-30 months of toddlers, and the association was consistent among toddlers of mothers without prenatal folic acid supplements. Our findings emphasize the need to raise awareness of the risk of unintended pregnancy and the benefits of folic acid supplements among Chinese women.

Diversity and Classification of Genetic Variations in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition with symptoms that affect the whole personality and all aspects of life. Although there is a high degree of heterogeneity in both its etiology and its characteristic behavioral patterns, the disorder is well-captured along the autistic triad. Currently, ASD status can be confirmed following an assessment of behavioral features, but there is a growing emphasis on conceptualizing autism as a spectrum, which allows for establishing a diagnosis based on the level of support need, free of discrete categories. Since ASD has a high genetic predominance, the number of genetic variations identified in the background of the condition is increasing exponentially as genetic testing methods are rapidly evolving. However, due to the huge amount of data to be analyzed, grouping the different DNA variations is still challenging. Therefore, in the present review, a multidimensional classification scheme was developed to accommodate most of the currently known genetic variants associated with autism. Genetic variations have been grouped according to six criteria (extent, time of onset, information content, frequency, number of genes involved, inheritance pattern), which are themselves not discrete categories, but form a coherent continuum in line with the autism spectrum approach.

All-cause mortality and suicide mortality in autistic individuals: An entire population longitudinal study in Taiwan

LAY ABSTRACT

Our study was the first population-based study in an Asian country to investigate the mortality rates among autistic individuals. Among the entire Taiwanese population (N = 29,253,529), between 2003 and 2017, 45,398 autistic individuals were identified and 1:4 age-/sex-matched to 181,592 non-autistic individuals. We found that autistic individuals had increased risks of all-cause mortality, natural-cause mortality, and suicide mortality compared with non-autistic individuals. Furthermore, autistic males were more likely to die by suicide, and autistic females were more likely to die of accident compared with the non-autistic individuals.

Autism spectrum disorder prevalence in Italy: a nationwide study promoted by the Ministry of Health

BACKGROUND

This nationwide study aimed to estimate Autism Spectrum Disorder (ASD) prevalence in 7-9-year-old Italian children. Promoted by Italy's Ministry of Health and coordinated by the National Observatory for Autism at the National Institute of Health, it covered schools in northern (Lecco and Monza-Brianza), central (Rome and its province), and southern (Palermo and its province) regions from February 24, 2016, to February 23, 2018, using a multi-stage approach defined by the European Union's ASD network.

METHODS

Phase one identified ASD-diagnosed children in mainstream schools through local Ministry of Education (MoE) disability registries. Phase two had a subset of schools screen 7-9-year-olds using the Social Communication Questionnaire-Life version (SCQ-L). Those with SCQ-L scores of 15 + underwent clinical consultation for ASD symptoms, cognitive abilities, and life skills. To counter potential false negatives, 20% scoring 11-14 were randomly assessed via Autism Diagnostic Interview-Revised (ADI-R).

RESULTS

MoE data revealed 9.8 per 1000 certified ASD children in the north, 12.2 in the central, and 10.3 in the south. In phase two, 35,823 SCQ-L questionnaires were distributed across 198 schools (northern: 11,190 in 49 schools, central: 13,628 in 87 schools, southern: 11,005 in 62 schools). Of SCQ-L respondents, 2.4% (n = 390) scored above the 15 cutoff. Among these, 100 had ASD diagnoses, and 50 had other diagnoses. Among 115 families assessed, 16.5% (n = 19) received ASD diagnoses.

CONCLUSIONS

The estimated prevalence of ASD in Italy was 13.4 (11.3-16.0) per 1,000 children aged 7-9 years, with a male-to-female ratio of 4.4:1. It will guide national policies in enhancing services tailored to the specific needs of autistic children.

Gut microbiota and autism spectrum disorders: where do we stand?

BACKGROUND

Children with autism spectrum disorder (ASD) often have digestive problems and microbial imbalances in their guts, suggesting that these conditions may play a role in the development of the disorder. Scopus-based research on the gut microbiota and ASD was examined in this bibliometric analysis to shed light on the current state of research and identify potential hotspots for future work in this area.

METHODS

We searched documents from the Scopus database and reference citation analysis to collect published data on the gut microbiota and ASD from 2003 to 2022. The downloaded document records were exported to VOSviewer v.1.6.19 to examine and visualize the collaboration between countries and determine the research hotspots.

RESULTS

The search yielded 958 articles specifically dedicated to gut microbiota and ASD. The number of publications in this field increased rapidly after 2013, with a peak in 2022. The United States (n = 267; 27.87%) was the most active country, followed by China (n = 171; 17.85%) and Italy (n = 96; 10.02). International collaboration was observed, with the USA playing a central role. University College Cork, Ireland, was the most productive institution (n = 24; 2.51%). The National Natural Science Foundation of China was the most active funding agency (n = 76; 7.93%). Nutrients journal had the highest number of publications (n = 28; 2.92%). The articles related to gut microbiota and ASD were highly cited, with an h-index of 108. The research themes identified focused on the modulation of gut microbiota as a potential therapy for children with ASD and gut-brain axis dysfunction in ASD.

CONCLUSIONS

In recent years, the study of gut microbiota and its association with ASD has garnered considerable interest as an emergent field of study. The results of this study substantially enhance our current understanding of the knowledge landscape in this field and illuminate potential avenues for future research. It is essential to emphasize the significance of devoting more resources to the newest and most promising research areas, such as investigating the potential therapeutic benefits of modulating the intestinal microbiota in children with ASD. This research has enormous potential and merits intensified focus and investigation.

Environmental Risk Factors, Protective Factors, and Biomarkers for Allergic Rhinitis: A Systematic Umbrella Review of the Evidence

Many potential environmental risk factors, protective factors, and biomarkers of AR have been published, but so far, the strength and consistency of their evidence are unclear. We conducted a comprehensive review of environmental risk, protective factors, and biomarkers for AR to establish the evidence hierarchy. We systematically searched Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to December 31, 2022. We calculated summary effect estimate (odds ratio (OR), relative risk (RR), hazard ratio (HR), and standardized mean difference (SMD)), 95% confidence interval, random effects p value, I2 statistic, 95% prediction interval, small study effects, and excess significance biases, and stratification of the level of evidence. Methodological quality was assessed by AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). We retrieved 4478 articles, of which 43 met the inclusion criteria. The 43 eligible articles identified 31 potential environmental risk factors (10,806,206 total population, two study not reported), 11 potential environmental protective factors (823,883 total population), and 34 potential biomarkers (158,716 total population) for meta-analyses. The credibility of evidence was convincing (class I) for tic disorders (OR = 2.89, 95% CI 2.11-3.95); and highly suggestive (class II) for early-life antibiotic use (OR = 3.73, 95% CI 3.06-4.55), exposure to indoor dampness (OR = 1.49, 95% CI 1.27-1.75), acetaminophen exposure (OR = 1.54, 95% CI 1.41-1.69), childhood acid suppressant use (OR = 1.40, 95% CI 1.23-1.59), exposure to indoor mold (OR = 1.66, 95% CI 1.26-2.18), coronavirus disease 2019 (OR = 0.11, 95% CI 0.06-0.22), and prolonged breastfeeding (OR = 0.72, 95% CI 0.65-0.79). This study is registered in PROSPERO (CRD42022384320).

Ketogenic Diet and Multiple Health Outcomes: An Umbrella Review of Meta-Analysis

Numerous studies have examined the effects of ketogenic diets (KD) on health-related outcomes through meta-analyses. However, the presence of biases may compromise the reliability of conclusions. Therefore, we conducted an umbrella review to collate and appraise the strength of evidence on the efficacy of KD interventions. We conducted a comprehensive search on PubMed, EMBASE, and the Cochrane Database until April 2023 to identify meta-analyses that investigated the treatment effects of KD for multiple health conditions, which yielded 23 meta-analyses for quantitative analyses. The evidence suggests that KD could increase the levels of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C), the respiratory exchange rate (RER), and could decrease total testosterone and testosterone levels (all p-random effects: <0.05). The combination of KD and physical activity can significantly reduce body weight and increase the levels of LDL-C and cortisol. In addition, KD was associated with seizure reduction in children, which can be explained by the ketosis state as induced by the diet. Furthermore, KD demonstrated a better alleviation effect in refractory childhood epilepsy, in terms of median effective rates for seizure reduction of ≥50%, ≥90%, and seizure freedom. However, the strength of evidence supporting the aforementioned associations was generally weak, thereby challenging their credibility. Consequently, future studies should prioritize stringent research protocols to ascertain whether KD interventions with longer intervention periods hold promise as a viable treatment option for various diseases.

Balancing risks and benefits of cannabis use: umbrella review of meta-analyses of randomised controlled trials and observational studies

OBJECTIVE

To systematically assess credibility and certainty of associations between cannabis, cannabinoids, and cannabis based medicines and human health, from observational studies and randomised controlled trials (RCTs).

DESIGN

Umbrella review.

DATA SOURCES

PubMed, PsychInfo, Embase, up to 9 February 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Systematic reviews with meta-analyses of observational studies and RCTs that have reported on the efficacy and safety of cannabis, cannabinoids, or cannabis based medicines were included. Credibility was graded according to convincing, highly suggestive, suggestive, weak, or not significant (observational evidence), and by GRADE (Grading of Recommendations, Assessment, Development and Evaluations) (RCTs). Quality was assessed with AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). Sensitivity analyses were conducted.

RESULTS

101 meta-analyses were included (observational=50, RCTs=51) (AMSTAR 2 high 33, moderate 31, low 32, or critically low 5). From RCTs supported by high to moderate certainty, cannabis based medicines increased adverse events related to the central nervous system (equivalent odds ratio 2.84 (95% confidence interval 2.16 to 3.73)), psychological effects (3.07 (1.79 to 5.26)), and vision (3.00 (1.79 to 5.03)) in people with mixed conditions (GRADE=high), improved nausea/vomit, pain, spasticity, but increased psychiatric, gastrointestinal adverse events, and somnolence among others (GRADE=moderate). Cannabidiol improved 50% reduction of seizures (0.59 (0.38 to 0.92)) and seizure events (0.59 (0.36 to 0.96)) (GRADE=high), but increased pneumonia, gastrointestinal adverse events, and somnolence (GRADE=moderate). For chronic pain, cannabis based medicines or cannabinoids reduced pain by 30% (0.59 (0.37 to 0.93), GRADE=high), across different conditions (n=7), but increased psychological distress. For epilepsy, cannabidiol increased risk of diarrhoea (2.25 (1.33 to 3.81)), had no effect on sleep disruption (GRADE=high), reduced seizures across different populations and measures (n=7), improved global impression (n=2), quality of life, and increased risk of somnolence (GRADE=moderate). In the general population, cannabis worsened positive psychotic symptoms (5.21 (3.36 to 8.01)) and total psychiatric symptoms (7.49 (5.31 to 10.42)) (GRADE=high), negative psychotic symptoms, and cognition (n=11) (GRADE=moderate). In healthy people, cannabinoids improved pain threshold (0.74 (0.59 to 0.91)), unpleasantness (0.60 (0.41 to 0.88)) (GRADE=high). For inflammatory bowel disease, cannabinoids improved quality of life (0.34 (0.22 to 0.53) (GRADE=high). For multiple sclerosis, cannabinoids improved spasticity, pain, but increased risk of dizziness, dry mouth, nausea, somnolence (GRADE=moderate). For cancer, cannabinoids improved sleep disruption, but had gastrointestinal adverse events (n=2) (GRADE=moderate). Cannabis based medicines, cannabis, and cannabinoids resulted in poor tolerability across various conditions (GRADE=moderate). Evidence was convincing from observational studies (main and sensitivity analyses) in pregnant women, small for gestational age (1.61 (1.41 to 1.83)), low birth weight (1.43 (1.27 to 1.62)); in drivers, car crash (1.27 (1.21 to 1.34)); and in the general population, psychosis (1.71 (1.47 to 2.00)). Harmful effects were noted for additional neonatal outcomes, outcomes related to car crash, outcomes in the general population including psychotic symptoms, suicide attempt, depression, and mania, and impaired cognition in healthy cannabis users (all suggestive to highly suggestive).

CONCLUSIONS

Convincing or converging evidence supports avoidance of cannabis during adolescence and early adulthood, in people prone to or with mental health disorders, in pregnancy and before and while driving. Cannabidiol is effective in people with epilepsy. Cannabis based medicines are effective in people with multiple sclerosis, chronic pain, inflammatory bowel disease, and in palliative medicine but not without adverse events.

STUDY REGISTRATION

PROSPERO CRD42018093045.

FUNDING

None.

Cognitive control in adults with high-functioning autism spectrum disorder: a study with event-related potentials

Introduction

Little is known about cognitive control in adults with high-functioning forms of autism spectrum disorder because previous research focused on children and adolescents. Cognitive control is crucial to monitor and readjust behavior after errors to select contextually appropriate reactions. The congruency effect and conflict adaptation are measures of cognitive control. Post-error slowing, error-related negativity and error positivity provide insight into behavioral and electrophysiological correlates of error processing. In children and adolescent with autism spectrum disorder deficits in cognitive control and error processing have been shown by changes in post-error slowing, error-related negativity and error positivity in the flanker task.

Methods

We performed a modified Eriksen flanker task in 17 adults with high-functioning autism spectrum disorder and 17 healthy controls. As behavioral measures of cognitive control and error processing, we included reaction times and error rates to calculate congruency effects, conflict adaptation, and post-error slowing. Event-related potentials namely error-related negativity and error positivity were measured to assess error-related brain activity.

Results

Both groups of participants showed the expected congruency effects demonstrated by faster and more accurate responses in congruent compared to incongruent trials. Healthy controls exhibited conflict adaptation as they obtained performance benefits after incongruent trials whereas patients with autism spectrum disorder did not. The expected slowing in reaction times after errors was observed in both groups of participants. Individuals with autism spectrum disorder demonstrated enhanced electrophysiological error-processing compared to healthy controls indicated by increased error-related negativity and error positivity difference amplitudes.

Discussion

Our findings show that adults with high-functioning autism spectrum disorder do not show the expected upregulation of cognitive control in response to conflicts. This finding implies that previous experiences may have a reduced influence on current behavior in these patients which possibly contributes to less flexible behavior. Nevertheless, we observed intact behavioral reactions after errors indicating that adults with high-functioning autism spectrum disorder can flexibly adjust behavior in response to changed environmental demands when necessary. The enhancement of electrophysiological error-processing indicates that adults with high-functioning autism spectrum disorder demonstrate an extraordinary reactivity toward errors reflecting increased performance monitoring in this subpopulation of autism spectrum disorder patients.

The impact of paternal mental illness on child development: an umbrella review of systematic reviews and meta-analyses

Whilst there is growing evidence highlighting the importance of paternal mental illness (PMI) on child development, this relationship still remains under-studied and often over-looked. Considering the increasingly active role of fathers in their children's upbringing, a comprehensive overview of the impact of PMI on child development is overdue. This study aimed to combine and synthesise currently available evidence on the relationship between PMI and multiple domains of child development. Narrative synthesis of systematic reviews and meta-analyses on the relationship between PMI and child development (mental health and social, emotional, language, cognitive or adaptive behaviour), published between 1980 to December 2021, was conducted in line with PRISMA 2020 guidelines. Review quality was assessed based on AMSTAR-2 criteria and respective study confidence was interpreted in line with GRADE scoring. All relevant meta-analytic effect sizes were converted to odds ratios (OR) and grouped using a random effects model. Grouped meta-analyses saw PMI to have a significant, detrimental effect on all studied domains of child development [OR: 1.54; 95% CI (1.36-1.74)]. Subgroup analyses saw PMI affecting both internalising [OR: 1.62; 95% CI (1.27-2.08)] and externalising [OR: 1.63; 95% CI (1.28-2.08)] child behaviours to a similar extent. However, included reviews were of poor methodological quality, demonstrating either low or critically low confidence. These results show a consistent and influential effect of PMI on child development. The relationship between fathers' mental illness and child development warrants further investigation, as current research is limited in scope, particularly regarding cognitive domains of child development and non-affective PMI diagnoses.

Reliability and agreement of the timed up and go test in children and teenagers with autism spectrum disorder

ASD patients include a variety of motor deficits; however, these issues have received less scientific attention than other ASD symptoms. Due to understanding and behavioral difficulties, it might be difficult to administer motor assessment measures to children and adolescents with ASD. To evaluate motor challenges in this population, including gait and dynamic balance issues, the timed up and go test (TUG) may be a simple, easy to apply, quick, and inexpensive tool. This test measures in seconds the time it takes for an individual to get up from a standard chair walk 3 m, turn around, walk back to the chair, and sit down again. The study purpose was to evaluate the inter- and intra-rater reliability of TUG test in children and teenagers with ASD. A total of 50 children and teenagers with ASD (43 boys and 7 girls) between 6 and 18 years were included. Reliability was verified by the intraclass correlation coefficient, standard error of measurement, and minimum detectable change. The agreement was analyzed by the Bland-Altman method. A good intra-rater reliability (ICC = 0.88; 95% CI = 0.79-0.93) and an excellent inter-rater reliability (ICC = 0,99; 95% CI = 0.98 to 0.99) were observed. Additionally, Bland-Altman plots demonstrated that there was no evidence of bias in either the replicates or between examiners. Furthermore, the limits of agreement (LOAs) between the testers and test replicates were close, indicating that there was little variation between measurements.       Conclusions: The test TUG showed strong intra- and inter-rater reliability values, low proportion of measurement errors, and lack of significant bias based on by test repetition in children and teenagers with ASD. These results could be clinically useful for assessing balance and the risk of falls in children and teenagers with ASD. However, the present study is not free of limitations, such as the use of a non-probabilistic sampling. What is Known: • People with ASD have a variety of motor deficits that have a prevalence rate almost as common as intellectual disability. In our knowledge, there are no studies that provide data on the reliability of the use of scales or assessment tests in children and adolescents with ASD to measure motor difficulties, such as gait and dynamic balance, in children and teenagers with ASD. • Timed up and go test (TUG) could be a possible tool to measure this motor skills. What is New: • The reliability and agreement of the Timed up and go test in 50 children and teenagers with autism spectrum disorder showed strong intra- and inter-rater reliability values, low proportion of measurement errors, and lack of significant bias based on by test repetition.

The efficacy of physical exercise interventions on mental health, cognitive function, and ADHD symptoms in children and adolescents with ADHD: an umbrella review

Background

A considerable number of published reviews have addressed the effects of physical exercise on mental health, cognitive function, or attention-deficit hyperactivity (ADHD) symptoms as outcomes in children and adolescents with ADHD. Their findings have often conflicted, therefore, there is an urgent need to synthesise a hierarchy of the evidence and examine the credibility of previous meta-analyses. To establish the robustness of these findings, we conducted an additional meta-analysis on a number of individual studies that were not covered in previous reviews but were suitable for inclusion in our own study.

Methods

Three reviewers independently searched Web of Science, Psych INFO, Embase, Cochrane Library, PubMed, SPORTDiscus, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) for meta-analyses published between database inceptions to December 1, 2022. The individual studies were also screened from 1 January 2015 to 1 December 2022. We included meta-analyses and eligible individual studies that addressed the effects of exercise on at least one outcome of mental health, cognitive function, or ADHD symptoms in children and adolescents with ADHD. We excluded systematic reviews and articles that lacked sufficient data for a meaningful second analysis. The effect estimates (Hedges' g), 95% confidence interval (95% CI), 95% prediction interval (95% PI), small study effects, and excess significance bias were calculated. Finally, we categorised the meta-analyses based on the credibility of the evidence criteria and their quality using a Measurement Tool to Assess Systematic Reviews 2 checklist. This umbrella review was registered with PROSPERO, CRD42022361331.

Findings

Of 181 listed review articles and 60 individual papers, 10 reviews and 12 individual articles were included in the meta-analyses. This yielded 37 meta-analyses based on 106 study estimates. Evidence was highly suggestive for the effectiveness of exercise (class II) for improving inattention (G = 0.92, 95% CI: 0.44-1.39, 95%), inhibitory control (G = 0.82, 95% CI: 0.52-1.13), and cognitive flexibility (G = 0.52, 95% CI: 0.32-0.72). However, evidence for the effectiveness of exercise on emotional, social, and working memory outcomes was weak, and these results were not significant for hyperactivity and behavioural functioning.

Interpretation

Improvement of cognitive flexibility, inhibitory control, and inattention in children and adolescents with ADHD was highly suggested by exercise interventions. However, results were weak for other outcomes (emotional functioning, social functioning, and working memory). Further high-quality randomised controlled trials are, therefore, warranted to determine the effectiveness of exercise on weak outcomes.

Funding

None.

Patterns of polysomnography parameters in 27 neuropsychiatric diseases: an umbrella review

BACKGROUND

We provide an umbrella review of the reported polysomnographic changes in patients with neuropsychiatric diseases compared with healthy controls.

METHODS

An electronic literature search was conducted in EMBASE, MEDLINE, All EBM databases, CINAHL, and PsycINFO. Meta-analyses of case-control studies investigating the polysomnographic changes in patients with neuropsychiatric diseases were included. For each meta-analysis, we estimated the summary effect size using random effects models, the 95% confidence interval, and the 95% prediction interval. We also estimated between-study heterogeneity, evidence of excess significance bias, and evidence of small-study effects. The levels of evidence of polysomnographic changes in neuropsychiatric diseases were ranked as follows: not significant, weak, suggestive, highly suggestive, or convincing.

RESULTS

We identified 27 articles, including 465 case-control studies in 27 neuropsychiatric diseases. The levels of evidence of polysomnographic changes in neuropsychiatric diseases were highly suggestive for increased sleep latency and decreased sleep efficiency (SE) in major depressive disorder (MDD), increased N1 percentage, and decreased N2 percentage, SL and REML in narcolepsy, and decreased rapid eye movement (REM) sleep percentage in Parkinson's disease (PD). The suggestive evidence decreased REM latency in MDD, decreased total sleep time and SE in PD, and decreased SE in posttraumatic stress disorder and in narcolepsy.

CONCLUSIONS

The credibility of evidence for sleep characteristics in 27 neuropsychiatric diseases varied across polysomnographic variables and diseases. When considering the patterns of altered PSG variables, no two diseases had the same pattern of alterations, suggesting that specific sleep profiles might be important dimensions for defining distinct neuropsychiatric disorders.

Brain perivascular spaces and autism: clinical and pathogenic implications from an innovative volumetric MRI study

Introduction

Our single-center case-control study aimed to evaluate the unclear glymphatic system alteration in autism spectrum disorder (ASD) through an innovative neuroimaging tool which allows to segment and quantify perivascular spaces in the white matter (WM-PVS) with filtering of non-structured noise and increase of the contrast-ratio between perivascular spaces and the surrounding parenchyma.

Methods

Briefly, files of 65 ASD and 71 control patients were studied. We considered: ASD type, diagnosis and severity level and comorbidities (i.e., intellectual disability, attention-deficit hyperactivity disorder, epilepsy, sleep disturbances). We also examined diagnoses other than ASD and their associated comorbidities in the control group.

Results

When males and females with ASD are included together, WM-PVS grade and WM-PVS volume do not significantly differ between the ASD group and the control group overall. We found, instead, that WM-PVS volume is significantly associated with male sex: males had higher WM-PVS volume compared to females (p = 0.01). WM-PVS dilation is also non-significantly associated with ASD severity and younger age (< 4 years). In ASD patients, higher WM-PVS volume was related with insomnia whereas no relation was found with epilepsy or IQ.

Discussion

We concluded that WM-PVS dilation can be a neuroimaging feature of male ASD patients, particularly the youngest and most severe ones, which may rely on male-specific risk factors acting early during neurodevelopment, such as a transient excess of extra-axial CSF volume. Our findings can corroborate the well-known strong male epidemiological preponderance of autism worldwide.

Human pluripotent stem cell (hPSC) and organoid models of autism: opportunities and limitations

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder caused by genetic or environmental perturbations during early development. Diagnoses are dependent on the identification of behavioral abnormalities that likely emerge well after the disorder is established, leaving critical developmental windows uncharacterized. This is further complicated by the incredible clinical and genetic heterogeneity of the disorder that is not captured in most mammalian models. In recent years, advancements in stem cell technology have created the opportunity to model ASD in a human context through the use of pluripotent stem cells (hPSCs), which can be used to generate 2D cellular models as well as 3D unguided- and region-specific neural organoids. These models produce profoundly intricate systems, capable of modeling the developing brain spatiotemporally to reproduce key developmental milestones throughout early development. When complemented with multi-omics, genome editing, and electrophysiology analysis, they can be used as a powerful tool to profile the neurobiological mechanisms underlying this complex disorder. In this review, we will explore the recent advancements in hPSC-based modeling, discuss present and future applications of the model to ASD research, and finally consider the limitations and future directions within the field to make this system more robust and broadly applicable.

Early-life exposure to endocrine-disrupting chemicals and autistic traits in childhood and adolescence: a systematic review of epidemiological studies

Aims

Exposure to endocrine-disrupting chemicals (EDCs) during critical neurodevelopmental windows has been associated with the risk of autistic traits. This systematic review of epidemiological studies examined the association between maternal exposure to EDCs during pregnancy and the risk of autism spectrum disorder (ASD) in the offspring.

Methods

We searched PubMed, Web of Science, Scopus, and Google Scholar from inception to November 17, 2022, for studies investigating the association between prenatal exposure to EDCs and outcomes related to ASD. Two independent reviewers screened studies for eligibility, extracted data, and assessed the risk of bias. The review was registered in PROSPERO (CRD42023389386).

Results

We included 27 observational studies assessing prenatal exposure to phthalates (8 studies), polychlorinated biphenyls (8 studies), organophosphate pesticides (8 studies), phenols (7 studies), perfluoroalkyl substances (6 studies), organochlorine pesticides (5 studies), brominated flame retardants (3 studies), dioxins (1 study), and parabens (1 study). The number of examined children ranged from 77 to 1,556, the age at the assessment of autistic traits ranged from 3 to 14 years, and most studies assessed autistic traits using the Social Responsiveness Scale. All but one study was considered to have a low risk of bias. Overall, there was no association between maternal exposure to specific ECDs during pregnancy and the occurrence of autistic traits in offspring.

Conclusions

Findings from the epidemiological studies evaluated here do not support an association between prenatal exposure to ECDs and the likelihood of autistic traits in later in life. These findings should not be interpreted as definitive evidence of the absence of neurodevelopment effects of EDCs affecting ASD risk, given the limitations of current studies such as representative exposure assessment, small sample sizes, inadequacy to assess sexually dimorphic effects, or the effects of EDC mixtures. Future studies should carefully address these limitations.

Who Is Attending? The Role of Child Ethnicity and Maternal Demographics in Research Engagement and Early Identification of Autism

Inequitable access to early autism developmental surveillance is evident globally. However, there is limited research examining autism diagnosis, ethnicity, and community profiles when engaging in research for the early identification of autism. We aimed to understand the relationships between child ethnicity, maternal demographics, and autism diagnosis, comparing retrospective data from the 2016 census for eight local government areas (LGAs) in Victoria, Australia. Maternal and child health (MCH) nurses monitored 13,511 children under 42 months for the early signs of autism using the Social Attention Communication Surveillance-Revised (SACS-R) and SACS-R Preschool (SACS-PR) tools during well-child checks. Of these, 340 children with a "high likelihood" of autism attended developmental assessments. Participants' maternal ethnicity ('European maternal ethnicity', EME; 'non-European maternal ethnicity,' N-EME; 'mixed maternal ethnicity,' MME'), socioeconomic factors, and autism prevalence were compared to their LGA community. Results indicated that study participants were representative of their LGA communities, though bi- and multilingualism was higher in our cohort. Differences in current maternal employment, maternal education, annual family income, and autism prevalence were found between the N-EME, EME, and MME groups. Our study found that research engagement was driven by maternal education, maternal employment, and annual family income, and further research is required to understand these relationships.

Shared and divergent contribution of vitamin A and oxytocin to the aetiology of autism spectrum disorder

Rare genetic variations contribute to the heterogeneity of autism spectrum disorder (ASD) and the responses to various interventions for ASD probands. However, the associated molecular underpinnings remain unclear. Herein, we estimated the association between rare genetic variations in 410 vitamin A (VA)-related genes (VARGs) and ASD aetiology using publicly available de novo mutations (DNMs), rare inherited variants, and copy number variations (CNVs) from about 50,000 ASD probands and 20,000 normal controls (discovery and validation cohorts). Additionally, given the functional relevance of VA and oxytocin, we systematically compared the similarities and differences between VA and oxytocin with respect to ASD aetiology and evaluated their potential for clinical applications. Functional DNMs and pathogenic CNVs in VARGs contributed to ASD pathogenesis in the discovery and validation cohorts. Additionally, 324 potential VA-related biomarkers were identified, 243 of which were shared with previously identified oxytocin-related biomarkers, while 81 were unique VA biomarkers. Moreover, multivariable logistic regression analysis revealed that both VA- and oxytocin-related biomarkers were able to predict ASD aetiology for individuals carrying functional DNM in corresponding biomarkers with an average precision of 0.94. As well as, convergent and divergent functions were also identified between VA- and oxytocin-related biomarkers. The findings of this study provide a basis for future studies aimed at understanding the pathophysiological mechanisms underlying ASD while also defining a set of potential molecular biomarkers for adjuvant diagnosis and intervention in ASD.

A snapshot of gut microbiota data from murine models of Autism Spectrum Disorder: Still a blurred picture

Autism Spectrum Disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized by deficits in social communication and interaction and repetitive/stereotyped behaviors. In recent years, the role of microbiota-gut-brain axis in ASD pathogenesis received growing attention, appearing as an attractive therapeutic target. We provide a comprehensive overview of changes in microbiota composition in ASD murine models so far identified, and summarize the therapeutic approaches targeting the microbiota on ASD-like neurobehavioral profile. Although alterations in microbiota composition have been observed in both genetic and environmental murine models of ASD, a clear microbiota profile shared by different ASD murine models has not been identified. We documented substantial discrepancies among studies (often within the same model), likely due to several confounding factors (from sex and age of animals to housing conditions). Despite these limitations, ASD animal models (under standardized conditions) remain a useful tool to evaluate (i) the beneficial effects of manipulations of gut microbiota on behavioral abnormalities; (ii) underlying neurobiological mechanisms related to gut-brain axis; and (iii) to identify optimal time windows for therapeutic interventions.

Translational Neuroscience Approaches to Understanding Autism

While autism spectrum disorder affects nearly 2% of children in the United States, little is known with certainty concerning the etiologies and brain systems involved. This is due, in part, to the substantial heterogeneity in the presentation of the core symptoms of autism as well as the great number of co-occurring conditions that are common in autistic individuals. Understanding the neurobiology of autism is further hampered by the limited availability of postmortem brain tissue to determine the cellular and molecular alterations that take place in the autistic brain. Animal models therefore provide great translational value in helping to define the neural systems that constitute the social brain and mediate repetitive behaviors or interests. If they are based on genetic or environmental factors that contribute to autism, organisms from flies to nonhuman primates may serve as models of the neural structure or function of the autistic brain. Ultimately, successful models can also be employed to test the safety and effectiveness of potential therapeutics. This is an overview of the major animal species that are currently used as models of autism, including an appraisal of the advantages and limitations of each.

Visual Autism

Autism spectrum disorder (ASD) is a lifelong neurodevelopmental disorder characterized by deficits in social communication and restricted, repetitive behaviors. It affects approximately 2.2% of children. Both genetic and environmental risk factors have been identified for ASD. Visual comorbidities are relatively common among children with ASD. Between 20 and 44% of ASD children have visually significant refractive error, on-third have strabismus, and one-fifth have amblyopia. In addition, ASD is 30 times more common in children with congenital blindness. It is unknown whether the association of ASD with visual morbidity is causal, comorbid, or contributing. Structural and functional abnormalities have been identified in MRIs of ASD children, and ASD children have been noted to have aberrant eye tracking. ASD children with visually significant refractive errors and poor spectacle compliance (present in 30% of ASD children) offer the opportunity for investigation into how improved visual acuity influences ASD behaviors. In this review, we focus on what is known of the visual system, refractive surgery, and ASD.

Poly(I:C)-induced maternal immune activation causes elevated self-grooming in male rat offspring: Involvement of abnormal postpartum static nursing in dam

Introduction: Maternal immune activation (MIA) is closely related to the onset of autism-like behaviors in offspring, but the mechanism remains unclear. Maternal behaviors can influence offspring’s development and behaviors, as indicated in both human and animal studies. We hypothesized that abnormal maternal behaviors in MIA dams might be other factors leading to delayed development and abnormal behaviors in offspring.

Methods: To verify our hypothesis, we analyzed poly(I:C)-induced MIA dam’s postpartum maternal behavior and serum levels of several hormones related to maternal behavior. Pup’s developmental milestones and early social communication were recorded and evaluated in infancy. Other behavioral tests, including three-chamber test, self-grooming test, open field test, novel object recognition test, rotarod test and maximum grip test, were performed in adolescence of pups.

Results: Our results showed that MIA dams exhibit abnormal static nursing behavior but normal basic care and dynamic nursing behavior. The serum levels of testosterone and arginine vasopressin in MIA dams were significantly reduced compared with control dams. The developmental milestones, including pinna detachment, incisor eruption and eye opening, were significantly delayed in MIA offspring compared with control offspring, while the weight and early social communication showed no significant differences between the two groups. Behavioral tests performed in adolescence showed that only male MIA offspring display elevated self-grooming behaviors and reduced maximum grip.

Discussion: In conclusion, MIA dams display abnormal postpartum static nursing behavior concomitantly with reduced serum levels of testosterone and arginine vasopressin, possibly involving in the pathogenesis of delayed development and elevated self-grooming in male offspring. These findings hint that improving dam’s postpartum maternal behavior might be a potential regime to counteract delayed development and elevated self-grooming in male MIA offspring.

Folate–Methionine Cycle Disruptions in ASD Patients and Possible Interventions: A Systematic Review

Autism Spectrum Disorder (ASD) has become a major public health concern due to its rapidly rising incidence over the past few years. Disturbances in folate or methionine metabolism have been identified in many individuals with ASD, suggesting that the folate–methionine cycle may play an essential role in the pathogenesis of autism. Thus, changes in metabolite concentrations associated with this cycle could be used as potential biomarkers and therapeutic targets for ASD. The aim of this systematic review is to elucidate the perturbations of this cycle and the possible interventions that may be proposed in this context. Several studies have shown that high levels of homocysteine and low levels of vitamins B12 and folate are associated with ASD. These changes in serum metabolites are influenced by poor diet. In fact, children with ASD tend to eat selectively, which could compromise the quality of their diet and result in nutrient deficiencies. Moreover, these disturbances may also be caused by genetic predispositions such as polymorphisms of the MTHFR gene. Few studies have demonstrated the beneficial effects of the use of nutritional supplements in treating ASD children. Therefore, larger, well-structured studies are recommended to examine the impact of vitamin B12 and folate supplementation on homocysteine levels.

Evaluation of the Lebanese Adults' Knowledge Regarding Autism Spectrum Disorder

The daily functioning and overall well-being of people with ASD depends largely on understanding how the wider public views ASD. Indeed, an increased level of ASD knowledge in the general population may result in earlier diagnosis, earlier intervention, and better overall outcomes. The present study aimed to examine the current state of ASD knowledge, beliefs, and sources of information in a Lebanese general population sample, to identify the factors that could influence this knowledge. A total of 500 participants were involved in this cross-sectional study, which was conducted in Lebanon between May 2022 and August 2022 using the Autism Spectrum Knowledge scale, General Population version (ASKSG). Overall, the participants' understanding of autism spectrum disorder was low, with a mean score of 13.8 (6.69) out of 32, or 43.1%. The highest knowledge score was found for items related to knowledge of the symptoms and associated behaviors (52%). However, the level of knowledge regarding the etiology and prevalence, assessment and diagnosis, treatment, outcomes, and prognosis of the disease was low (29%, 39.2%, 46%, and 43.4%, respectively). Moreover, age, gender, place of residence, sources of information, and ASD case were all statistically significant predictors of ASD knowledge (p < 0.001, p < 0.001, and p = 0.012, p < 0.001, p < 0.001, respectively). The general public in Lebanon perceive a lack of awareness and insufficient knowledge regarding ASD. This results in delayed identification and intervention, leading to unsatisfactory outcomes in patients. Raising awareness about autism among parents, teachers, and healthcare professionals should be a top priority.

Nexus between genome-wide copy number variations and autism spectrum disorder in Northeast Han Chinese population

BACKGROUND

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder, with an increasing prevalence worldwide. Copy number variation (CNV), as one of genetic factors, is involved in ASD etiology. However, there exist substantial differences in terms of location and frequency of some CNVs in the general Asian population. Whole-genome studies of CNVs in Northeast Han Chinese samples are still lacking, necessitating our ongoing work to investigate the characteristics of CNVs in a Northeast Han Chinese population with clinically diagnosed ASD.

METHODS

We performed a genome-wide CNVs screening in Northeast Han Chinese individuals with ASD using array-based comparative genomic hybridization.

RESULTS

We found that 22 kinds of CNVs (6 deletions and 16 duplications) were potentially pathogenic. These CNVs were distributed in chromosome 1p36.33, 1p36.31, 1q42.13, 2p23.1-p22.3, 5p15.33, 5p15.33-p15.2, 7p22.3, 7p22.3-p22.2, 7q22.1-q22.2, 10q23.2-q23.31, 10q26.2-q26.3, 11p15.5, 11q25, 12p12.1-p11.23, 14q11.2, 15q13.3, 16p13.3, 16q21, 22q13.31-q13.33, and Xq12-q13.1. Additionally, we found 20 potential pathogenic genes of ASD in our population, including eight protein coding genes (six duplications [DRD4, HRAS, OPHN1, SHANK3, SLC6A3, and TSC2] and two deletions [CHRNA7 and PTEN]) and 12 microRNAs-coding genes (ten duplications [MIR202, MIR210, MIR3178, MIR339, MIR4516, MIR4717, MIR483, MIR675, MIR6821, and MIR940] and two deletions [MIR107 and MIR558]).

CONCLUSION

We identified CNVs and genes implicated in ASD risks, conferring perception to further reveal ASD etiology.

Candidate diagnostic biomarkers for neurodevelopmental disorders in children and adolescents: a systematic review

Neurodevelopmental disorders - including attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, communication disorders, intellectual disability, motor disorders, specific learning disorders, and tic disorders - manifest themselves early in development. Valid, reliable and broadly usable biomarkers supporting a timely diagnosis of these disorders would be highly relevant from a clinical and public health standpoint. We conducted the first systematic review of studies on candidate diagnostic biomarkers for these disorders in children and adolescents. We searched Medline and Embase + Embase Classic with terms relating to biomarkers until April 6, 2022, and conducted additional targeted searches for genome-wide association studies (GWAS) and neuroimaging or neurophysiological studies carried out by international consortia. We considered a candidate biomarker as promising if it was reported in at least two independent studies providing evidence of sensitivity and specificity of at least 80%. After screening 10,625 references, we retained 780 studies (374 biochemical, 203 neuroimaging, 133 neurophysiological and 65 neuropsychological studies, and five GWAS), including a total of approximately 120,000 cases and 176,000 controls. While the majority of the studies focused simply on associations, we could not find any biomarker for which there was evidence - from two or more studies from independent research groups, with results going into the same direction - of specificity and sensitivity of at least 80%. Other important metrics to assess the validity of a candidate biomarker, such as positive predictive value and negative predictive value, were infrequently reported. Limitations of the currently available studies include mostly small sample size, heterogeneous approaches and candidate biomarker targets, undue focus on single instead of joint biomarker signatures, and incomplete accounting for potential confounding factors. Future multivariable and multi-level approaches may be best suited to find valid candidate biomarkers, which will then need to be validated in external, independent samples and then, importantly, tested in terms of feasibility and cost-effectiveness, before they can be implemented in daily clinical practice.

The environmental risk factors associated with ectopic pregnancy: An umbrella review

INTRODUCTION

Ectopic pregnancy(EP) is the implantation of a fertilized ovum outside of the uterine cavity. The incidence of EP has steadily increased around the world. The present umbrella review evaluated risk factors prior to conception associated with EP based on meta-analyses and systematic reviews.

METHODS

We searched PubMed, Scopus, and Web of Science until June 25, 2021. All meta-analyses that had focused on assessing the risk factors associated with EP were included. We calculated summary effect estimates, 95% CI, heterogeneity I², 95% prediction interval, small-study effects, excess significance biases, and sensitive analysis. The quality of the meta-analyses was evaluated with A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2).

RESULTS

Two risk factors including chlamydia trachomatis (OR: 3.03) and smoking (OR: 1·77) were graded as suggestive evidence (class III). IUD with pregnant control (OR: 10.63) and endometriosis for case-control studies (OR: 2·66) and tubal ligation with pregnant control (OR: 9.3) were graded as risk factors with weak evidence (class IV). Tubal ligation with non-pregnant control was a protective factor (class IV). IUD with non-pregnant control and endometriosis for cohort studies were not as risk factors for EP.

CONCLUSION

Two risk factors including chlamydia trachomatis and smoking were graded as suggestive evidence. IUD with pregnant control and endometriosis for case-control studies and tubal ligation with pregnant control were graded as risk factors with weak evidence. Strong evidence for risk factors of EP was not achieved, indicating the degree of uncertainty and bias, which bring an emergency to conduct further no-bias studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO (CRD42021281632).

Nutritional Status and Feeding Behavior of Children with Autism Spectrum Disorder in the Middle East and North Africa Region: A Systematic Review

Autism spectrum disorder (ASD) in children is associated with increased risks of overweight/obesity and underweight, altered nutrient profile, and abnormal feeding behaviors. This systematic review aimed to elucidate the literature on the nutritional status of children with ASD in the Middle East North Africa (MENA) region, by providing a summary and assessment of the body of evidence. A systematic review of English and Arabic publications up to November 2020 was conducted of five databases in addition to the grey literature, which include a nutrition-related parameter, from both experimental and observational study designs. Children with ASD (ASD-C) between 2 and 19 years in the MENA Region were the target population. For risk of bias, the Academy of Nutrition and Dietetics' Quality Criteria Checklist (QCC) was adopted. The number of published articles was grossly limited. Forty-three articles were included, of which only four articles reported a low risk of bias; therefore, the results were interpreted in light of methodological limitations. Both overweight and underweight were common in ASD-C, although not consistently different than typically developing children. Nutrient inadequacies of energy, protein, omega-3, and others; deficiencies in serum iron indicators and calcium, as well as vitamins B12, B9, and D levels; and higher levels of homocysteine and omega-6/omega-3 ratios were reported. Feeding behavior problems were also common in ASD-C. Understanding nutritional requirements and food preferences can guide the planning of the appropriate comprehensive interventions for ASD-C. Various nutritional and behavioral concerns were identified in the included studies; however, they were subject to methodological weaknesses, which limited the generalizability of these results. Future research is warranted that must be directed to finding strong evidence using robust study designs on nutritional status and feeding behaviors of ASD-C, with a particular emphasis on the MENA Region.

Autism Spectrum Disorder: A Review

IMPORTANCE

Autism spectrum disorder (ASD), characterized by deficits in social communication and the presence of restricted, repetitive behaviors or interests, is a neurodevelopmental disorder affecting approximately 2.3% children aged 8 years in the US and approximately 2.2% of adults. This review summarizes evidence on the diagnosis and treatment of ASD.

OBSERVATIONS

The estimated prevalence of ASD has been increasing in the US, from 1.1% in 2008 to 2.3% in 2018, which is likely associated with changes in diagnostic criteria, improved performance of screening and diagnostic tools, and increased public awareness. No biomarkers specific to the diagnosis of ASD have been identified. Common early signs and symptoms of ASD in a child's first 2 years of life include no response to name when called, no or limited use of gestures in communication, and lack of imaginative play. The criterion standard for the diagnosis of ASD is a comprehensive evaluation with a multidisciplinary team of clinicians and is based on semistructured direct observation of the child's behavior and semistructured caregiver interview focused on the individual's development and behaviors using standardized measures, such as the Autism Diagnostic Observation Schedule-Second Edition and the Autism Diagnostic Interview. These diagnostic measures have sensitivity of 91% and 80% and specificity of 76% and 72%, respectively. Compared with people without ASD, individuals with ASD have higher rates of depression (20% vs 7%), anxiety (11% vs 5%), sleep difficulties (13% vs 5%), and epilepsy (21% with co-occurring intellectual disability vs 0.8%). Intensive behavioral interventions, such as the Early Start Denver Model, are beneficial in children 5 years or younger for improvement in language, play, and social communication (small to medium effect size based on standardized mean difference). Pharmacotherapy is indicated for co-occurring psychiatric conditions, such as emotion dysregulation or attention-deficit/hyperactivity disorder. Risperidone and aripiprazole can improve irritability and aggression (standardized mean difference of 1.1, consistent with a large effect size) compared with placebo. Psychostimulants are effective for attention-deficit/hyperactivity disorder (standardized mean difference of 0.6, consistent with a moderate effect size) compared with placebo. These medications are associated with adverse effects including, most commonly, changes in appetite, weight, and sleep.

CONCLUSIONS AND RELEVANCE

ASD affects approximately 2.3% of children aged 8 years and approximately 2.2% of adults in the US. First-line therapy consists of behavioral interventions, while co-occurring psychiatric conditions, such as anxiety or aggression, may be treated with specific behavioral therapy or medication.

Interactions of genetic risks for autism and the broad autism phenotypes

Background

Common polygenic risk and de novo variants (DNVs) capture a small proportion of autism spectrum disorder (ASD) liability, and ASD phenotypic heterogeneity remains difficult to explain. Integrating multiple genetic factors contribute to clarifying the risk and clinical presentation of ASD.

Methods

In our study, we investigated the individual and combined effects of polygenic risk, damaging DNVs (including those in ASD risk genes), and sex among 2,591 ASD simplex families in the Simons Simplex Collection. We also explored the interactions among these factors, along with the broad autism phenotypes of ASD probands and their unaffected siblings. Finally, we combined the effects of polygenic risk, damaging DNVs in ASD risk genes, and sex to explain the total liability of ASD phenotypic spectrum.

Results

Our findings revealed that both polygenic risk and damaging DNVs contribute to an increased risk for ASD, with females exhibiting higher genetic burdens than males. ASD probands that carry damaging DNVs in ASD risk genes showed reduced polygenic risk. The effects of polygenic risk and damaging DNVs on autism broad phenotypes were inconsistent; probands with higher polygenic risk exhibited improvement in some behaviors, such as adaptive/cognitive behaviors, while those with damaging DNVs exhibited more severe phenotypes. Siblings with higher polygenic risk and damaging DNVs tended to have higher scores on broader autism phenotypes. Females exhibited more severe cognitive and behavioral problems compared to males among both ASD probands and siblings. The combination of polygenic risk, damaging DNVs in ASD risk genes, and sex explained 1-4% of the total liability of adaptive/cognitive behavior measurements.

Conclusion

Our study revealed that the risk for ASD and the autism broad phenotypes likely arises from a combination of common polygenic risk, damaging DNVs (including those in ASD risk genes), and sex.

Implication of Hippocampal Neurogenesis in Autism Spectrum Disorder: Pathogenesis and Therapeutic Implications

Autism spectrum disorder (ASD) is a cluster of heterogeneous neurodevelopmental conditions with atypical social communication and repetitive sensory-motor behaviors. The formation of new neurons from neural precursors in the hippocampus has been unequivocally demonstrated in the dentate gyrus of rodents and non-human primates. Accumulating evidence sheds light on how the deficits in the hippocampal neurogenesis may underlie some of the abnormal behavioral phenotypes in ASD. In this review, we describe the current evidence concerning pre-clinical and clinical studies supporting the significant role of hippocampal neurogenesis in ASD pathogenesis, discuss the possibility of improving hippocampal neurogenesis as a new strategy for treating ASD, and highlight the prospect of emerging pro-neurogenic therapies for ASD.

Global, regional, and national disease burden of autism spectrum disorder among children under 5 years from 1990 to 2019: An analysis for the Global Burden of Disease 2019 Study

AIM

To estimate the trend in burden of autism spectrum disorder (ASD) at global, regional, and national levels from 1990 to 2019.

METHODS

Annual incident cases, incidence rates, prevalent cases, prevalence rates, disability-adjusted life years (DALYs), and DALY rates of ASD among children under 5 years from 1990 to 2019 were collected from the Global Burden of Diseases Study 2019. The percentage of relative changes in cases and the estimated annual percentage changes (EAPCs) of rates were calculated to reflect the temporal trends of ASD burden. Pearson correlation analysis was used to explore the influential factors for EAPC.

RESULTS

Globally, the incidence rate, prevalence rate, and DALY rate of ASD among children under 5 years were 91.09 per 100,000, 439.39 per 100,000, and 68.67 per 100,000 in 2019, respectively. From 1990-2019, the incidence rate decreased (EAPC = -0.09, 95% confidence interval [CI] -0.12 to -0.06), whereas the prevalence rate (EAPC=0.08, 95%CI 0.06-0.09) and DALY rate (EAPC=0.08, 95%CI 0.07-0.10) increased. The largest increases in prevalent cases (80.26%) and DALYs (81.24%) were found in low SDI regions, while High-income North America experienced the fastest increase in incidence rate, prevalence rate, and DALY rate. Moreover, the burden of ASD among male children under 5 years was approximately three times that among female children, despite the slight narrowing of gender disparity. The EAPC of incidence rate was positively correlated with SDI and UHCI in 2019 (P < 0.001).

CONCLUSION

ASD is a noticeable child neurodevelopmental syndrome. More attention should be given to early screening, diagnosis, and intervention, particularly in resource-limited areas.

Unsaturated Fatty Acids in Mental Disorders: An Umbrella Review of Meta-Analyses

Unsaturated fatty acids might be involved in the prevention of and improvement in mental disorders, but the evidence on these associations has not been comprehensively assessed. This umbrella review aimed to appraise the credibility of published evidence evaluating the associations between unsaturated fatty acids and mental disorders. In this umbrella review, systematic reviews and meta-analyses of studies comparing unsaturated fatty acids (including supplementation, dietary intake, and blood concentrations) in participants with mental disorders with healthy individuals were included. We reanalyzed summary estimates, between-study heterogeneity, predictive intervals, publication bias, small-study effects, and excess significance bias for each meta-analysis. Ninety-five meta-analyses from 29 systematic reviews were included, encompassing 43 studies on supplementation interventions, 32 studies on dietary factors, and 20 studies on blood biomarkers. Suggestive evidence was only observed for dietary intake, in which higher intake of fish was associated with reduced risk of depression (RR: 0.78; 95% CI: 0.69, 0.89) and Alzheimer disease (RR: 0.74; 95% CI: 0.63, 0.87), and higher intake of total PUFAs might be associated with a lower risk of mild cognitive impairment (RR: 0.71; 95% CI: 0.61, 0.84). Evidence showed that PUFA supplementation was favorable but had weak credibility in anxiety, depression, attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), dementia, mild cognitive impairment, Huntington's disease, and schizophrenia (P-random effects <0.001-0.040). There was also weak evidence on the effect of decreased circulating n-3 (ɷ-3) PUFAs among patients on risk of ADHD, ASD, bipolar disorder, and schizophrenia (P-random effects <10-6-0.037). Our results suggest that higher levels of unsaturated fatty acids may relieve symptoms or reduce the risk of various mental disorders; however, the strength of the associations and credibility of the evidence were generally weak. Future high-quality research is needed to identify whether PUFA interventions should be prioritized to alleviate mental disorders.