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Journal of Autism and Developmental... Aug 2023The suggested overlap between autism spectrum disorder (ASD) and gender dysphoria/incongruence (GD/GI) has been much disputed. This review showed a relationship between... (Meta-Analysis)
Meta-Analysis
The suggested overlap between autism spectrum disorder (ASD) and gender dysphoria/incongruence (GD/GI) has been much disputed. This review showed a relationship between ASD traits and GD feelings in the general population and a high prevalence of GD/GI in ASD. Our meta-analyses revealed that the pooled estimate of the prevalence of ASD diagnoses in GD/GI people was 11% (p < .001) and the overall effect size of the difference in ASD traits between GD/GI and control people was significant (g = 0.67, p < .001). Heterogeneity was high in both meta-analyses. We demonstrated that the chances that there is not a link between ASD and GD/GI are negligible, yet the size of it needs further investigation.
Topics: Humans; Gender Dysphoria; Autism Spectrum Disorder; Prevalence
PubMed: 35596023
DOI: 10.1007/s10803-022-05517-y -
JAMA Network Open Dec 2023Contemporary studies raise concerns regarding the implications of excessive screen time on the development of autism spectrum disorder (ASD). However, the existing... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Contemporary studies raise concerns regarding the implications of excessive screen time on the development of autism spectrum disorder (ASD). However, the existing literature consists of mixed and unquantified findings.
OBJECTIVE
To conduct a systematic review and meta-analyis of the association between screen time and ASD.
DATA SOURCES
A search was conducted in the PubMed, PsycNET, and ProQuest Dissertation & Theses Global databases for studies published up to May 1, 2023.
STUDY SELECTION
The search was conducted independently by 2 authors. Included studies comprised empirical, peer-reviewed articles or dissertations published in English with statistics from which relevant effect sizes could be calculated. Discrepancies were resolved by consensus.
DATA EXTRACTION AND SYNTHESIS
This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline. Two authors independently coded all titles and abstracts, reviewed full-text articles against the inclusion and exclusion criteria, and resolved all discrepancies by consensus. Effect sizes were transformed into log odds ratios (ORs) and analyzed using a random-effects meta-analysis and mixed-effects meta-regression. Study quality was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. Publication bias was tested via the Egger z test for funnel plot asymmetry. Data analysis was performed in June 2023.
MAIN OUTCOMES AND MEASURES
The 2 main variables of interest in this study were screen time and ASD. Screen time was defined as hours of screen use per day or per week, and ASD was defined as an ASD clinical diagnosis (yes or no) or ASD symptoms. The meta-regression considered screen type (ie, general use of screens, television, video games, computers, smartphones, and social media), age group (children vs adults or heterogenous age groups), and type of ASD measure (clinical diagnosis vs ASD symptoms).
RESULTS
Of the 4682 records identified, 46 studies with a total of 562 131 participants met the inclusion criteria. The studies were observational (5 were longitudinal and 41 were cross-sectional) and included 66 relevant effect sizes. The meta-analysis resulted in a positive summary effect size (log OR, 0.54 [95% CI, 0.34 to 0.74]). A trim-and-fill correction for a significant publication bias (Egger z = 2.15; P = .03) resulted in a substantially decreased and nonsignificant effect size (log OR, 0.22 [95% CI, -0.004 to 0.44]). The meta-regression results suggested that the positive summary effect size was only significant in studies targeting general screen use (β [SE] = 0.73 [0.34]; t58 = 2.10; P = .03). This effect size was most dominant in studies of children (log OR, 0.98 [95% CI, 0.66 to 1.29]). Interestingly, a negative summary effect size was observed in studies investigating associations between social media and ASD (log OR, -1.24 [95% CI, -1.51 to -0.96]).
CONCLUSIONS AND RELEVANCE
The findings of this systematic review and meta-analysis suggest that the proclaimed association between screen use and ASD is not sufficiently supported in the existing literature. Although excessive screen use may pose developmental risks, the mixed findings, the small effect sizes (especially when considering the observed publication bias), and the correlational nature of the available research require further scientific investigation. These findings also do not rule out the complementary hypothesis that children with ASD may prioritize screen activities to avoid social challenges.
Topics: Child; Adult; Humans; Autism Spectrum Disorder; Screen Time; Publication Bias
PubMed: 38064216
DOI: 10.1001/jamanetworkopen.2023.46775 -
Cureus Jul 2023Autism spectrum disorder (ASD) is a neurological deficit in brain functions that prevents a child from having a normal social life like his peers. It results in the... (Review)
Review
Autism spectrum disorder (ASD) is a neurological deficit in brain functions that prevents a child from having a normal social life like his peers. It results in the inability to interact and communicate with others. Unsurprisingly, the alarming increase in screen-time exposure in children has become even more of a concern. Electronic devices are a double-edged sword. Despite their benefits, they have many potential hazards to children's neurological development. Previous studies have investigated the effects of unsupervised screen time and its impact on white matter development during the early years of life of children. The white matter has an important role in the development of neurological functions. This systematic review aims to qualitatively analyze the literature available on early screen time exposure and its association with the risk of developing ASD. This systematic review implemented the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) 2020 guidelines. PubMed, PubMed Central (PMC), Google Scholar, and Cochrane Library databases were searched for data in the recent six years. A total of 27,200 articles were identified using the MeSH and keywords through four selected databases. Search results revealed 70 from PubMed, 17,700 from Google Scholar, zero from Cochrane Library, and 9,430 from PubMed Central. After applying filters and screening the results by title and abstract and then by full text, 11 studies fulfilled the criteria to be included in the review. We found that the longer the period of screen exposure, the higher the risk that the child may develop ASD. Further, the earlier the child is exposed to screens, the higher the risk of developing ASD in children compared to children exposed later.
PubMed: 37614255
DOI: 10.7759/cureus.42292 -
Neuroscience and Biobehavioral Reviews Dec 2023This systematic review estimates the prevalence of co-occurring conditions (CCs) in children and adults with autism. A comprehensive search strategy consulting existing... (Meta-Analysis)
Meta-Analysis Review
This systematic review estimates the prevalence of co-occurring conditions (CCs) in children and adults with autism. A comprehensive search strategy consulting existing guidelines, diagnostic manuals, experts, carers, and autistic people was developed. PubMed and PsycInfo databases from inception to May 2022 were searched. PROSPERO registration: CRD42019132347. Two blind authors screened and extracted the data. Prevalence estimates for different CCs were summarized by using random effects models. Subgroup analyses were performed for age groups (children/adolescents vs adults) and study designs (population/registry-based vs clinical sample-based). Of 19,932 studies, 340 publications with about 590,000 participants were included and meta-analyzed to estimate the prevalence of 38-point prevalence, 27-lifetime, and 3 without distinction between point and lifetime prevalence. Point prevalence of developmental coordination disorder, sleep-wake problem, gastrointestinal problem, ADHD, anxiety disorder, overweight/obesity, feeding and eating disorder, elimination disorder, disruptive behavior, and somatic symptoms and related disorder were the most frequent CCs. Prevalence differed depending on the age group and study design. Knowing specific CCs linked to autism helps professional investigations and interventions for improved outcomes.
Topics: Child; Adolescent; Adult; Humans; Autism Spectrum Disorder; Prevalence; Obesity; Autistic Disorder; Overweight
PubMed: 37913872
DOI: 10.1016/j.neubiorev.2023.105436 -
Pharmacology, Biochemistry, and Behavior Sep 2023Cannabis-derived compounds, such as cannabidiol (CBD) and delta-9-trans-tetrahydrocannabinol (THC), are increasingly prescribed for a range of clinical indications.... (Review)
Review
Cannabis-derived compounds, such as cannabidiol (CBD) and delta-9-trans-tetrahydrocannabinol (THC), are increasingly prescribed for a range of clinical indications. These phyto-cannabinoids have multiple biological targets, including the body's endocannabinoid system. There is growing scientific interest in the use of CBD, a non-intoxicating compound, to ameliorate symptoms associated with neurodevelopmental disorders. However, its suitability as a pharmaceutical intervention has not been reliably established in these clinical populations. This systematic review examines the nine published randomised controlled trials (RCTs) that have probed the safety and efficacy of CBD in individuals diagnosed with attention deficit hyperactivity disorder, autism spectrum disorder, intellectual disability, Tourette Syndrome, and complex motor disorders. Studies were identified systematically through searching four databases: Medline, CINAHL complete, PsycINFO, and EMBASE. Inclusion criteria were randomised controlled trials involving CBD and participants with neurodevelopmental disorders. No publication year or language restrictions were applied. Relevant data were extracted from the identified list of eligible articles. After extraction, data were cross-checked between the authors to ensure consistency. Several trials indicate potential efficacy, although this possibility is currently too inconsistent across RCTs to confidently guide clinical usage. Study characteristics, treatment properties, and outcomes varied greatly across the included trials. The material lack of comparable RCTs leaves CBD's suitability as a pharmacological treatment for neurodevelopmental disorders largely undetermined. A stronger evidence base is urgently required to establish safety and efficacy profiles and guide the ever-expanding clinical uptake of cannabis-derived compounds in neurodevelopmental disorders. Prospero registration number: CRD42021267839.
Topics: Humans; Cannabidiol; Cannabinoids; Cannabis; Hallucinogens; Attention Deficit Disorder with Hyperactivity; Dronabinol; Randomized Controlled Trials as Topic
PubMed: 37543051
DOI: 10.1016/j.pbb.2023.173607 -
Autism : the International Journal of... Nov 2023The way autism is represented in fictional media can impact people's views of autistic people. For example, representations may contribute to negative views of autistic... (Review)
Review
The way autism is represented in fictional media can impact people's views of autistic people. For example, representations may contribute to negative views of autistic people as being unusual or dangerous, or they may challenge stereotypes and instead highlight the strengths of autistic people. This work aimed to review previous research to understand how autistic people have been represented in fictional media (Part A). It also sought to understand whether viewing fictional portrayals of autism has an impact on people's knowledge of autism and attitudes towards autistic people (Part B). Of 14 studies that were included in Part A, several unhelpful and stereotypical portrayals of autism emerged. Positive portrayals were those that highlighted the strengths of autistic people and reflected nuance. There is a need for greater diversity in representation of autism in fictional media. For example, not all autistic people are white heterosexual males. Across the five studies included in Part B, there were no improvements in people's knowledge of autism after watching or reading a short segment from a fictional TV series or novel that depicts an autistic person. Although there was a significant improvement in people's attitudes towards autistic people, these findings do not provide a complete picture given the short length of the media exposure and small number of studies. Future studies should investigate how multiple exposures to the representation of autistic people in both fictional and non-fictional sources can affect people's understanding of autism. There is also a need to develop more accurate and respectful ways of measuring people's knowledge of, and attitudes towards, autism.
Topics: Male; Humans; Autistic Disorder; Autism Spectrum Disorder; Stereotyped Behavior; Respect; Stereotypic Movement Disorder
PubMed: 36802826
DOI: 10.1177/13623613231155770 -
BMJ (Clinical Research Ed.) Nov 2023To summarize the breadth and quality of evidence supporting commonly recommended early childhood autism interventions and their estimated effects on developmental... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To summarize the breadth and quality of evidence supporting commonly recommended early childhood autism interventions and their estimated effects on developmental outcomes.
DESIGN
Updated systematic review and meta-analysis (autism intervention meta-analysis; Project AIM).
DATA SOURCES
A search was conducted in November 2021 (updating a search done in November 2017) of the following databases and registers: Academic Search Complete, CINAHL Plus with full text, Education Source, Educational Administration Abstracts, ERIC, Medline, ProQuest Dissertations and Theses, PsycINFO, Psychology and Behavioral Sciences Collection, and SocINDEX with full text, , and ClinicalTrials.gov.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
Any controlled group study testing the effects of any non-pharmacological intervention on any outcome in young autistic children younger than 8 years.
REVIEW METHODS
Newly identified studies were integrated into the previous dataset and were coded for participant, intervention, and outcome characteristics. Interventions were categorized by type of approach (such as behavioral, developmental, naturalistic developmental behavioral intervention, and technology based), and outcomes were categorized by domain (such as social communication, adaptive behavior, play, and language). Risks of bias were evaluated following guidance from Cochrane. Effects were estimated for all intervention and outcome types with sufficient contributing data, stratified by risk of bias, using robust variance estimation to account for intercorrelation of effects within studies and subgroups.
RESULTS
The search yielded 289 reports of 252 studies, representing 13 304 participants and effects for 3291 outcomes. When contributing effects were restricted to those from randomized controlled trials, significant summary effects were estimated for behavioral interventions on social emotional or challenging behavior outcomes (Hedges' g=0.58, 95% confidence interval 0.11 to 1.06; P=0.02), developmental interventions on social communication (0.28, 0.12 to 0.44; P=0.003); naturalistic developmental behavioral interventions on adaptive behavior (0.23, 0.02 to 0.43; P=0.03), language (0.16, 0.01 to 0.31; P=0.04), play (0.19, 0.02 to 0.36; P=0.03), social communication (0.35, 0.23 to 0.47; P<0.001), and measures of diagnostic characteristics of autism (0.38, 0.17 to 0.59; P=0.002); and technology based interventions on social communication (0.33, 0.02 to 0.64; P=0.04) and social emotional or challenging behavior outcomes (0.57, 0.04 to 1.09; P=0.04). When effects were further restricted to exclude caregiver or teacher report outcomes, significant effects were estimated only for developmental interventions on social communication (0.31, 0.13 to 0.49; P=0.003) and naturalistic developmental behavioral interventions on social communication (0.36, 0.23 to 0.49; P<0.001) and measures of diagnostic characteristics of autism (0.44, 0.20 to 0.68; P=0.002). When effects were then restricted to exclude those at high risk of detection bias, only one significant summary effect was estimated-naturalistic developmental behavioral interventions on measures of diagnostic characteristics of autism (0.30, 0.03 to 0.57; P=0.03). Adverse events were poorly monitored, but possibly common.
CONCLUSION
The available evidence on interventions to support young autistic children has approximately doubled in four years. Some evidence from randomized controlled trials shows that behavioral interventions improve caregiver perception of challenging behavior and child social emotional functioning, and that technology based interventions support proximal improvements in specific social communication and social emotional skills. Evidence also shows that developmental interventions improve social communication in interactions with caregivers, and naturalistic developmental behavioral interventions improve core challenges associated with autism, particularly difficulties with social communication. However, potential benefits of these interventions cannot be weighed against the potential for adverse effects owing to inadequate monitoring and reporting.
Topics: Child; Humans; Child, Preschool; Autistic Disorder; Behavior Therapy; Early Intervention, Educational; Social Skills; Adaptation, Psychological
PubMed: 37963634
DOI: 10.1136/bmj-2023-076733 -
International Journal of Molecular... Nov 2023Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by several core symptoms: restricted interests, communication difficulties, and... (Review)
Review
Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by several core symptoms: restricted interests, communication difficulties, and impaired social interactions. Many ASD children experience gastrointestinal functional disorders, impacting their well-being. Emerging evidence suggests that a gut microbiota imbalance may exacerbate core and gastrointestinal symptoms. Our review assesses the gut microbiota in children with ASD and interventions targeting microbiota modulation. The analysis of forty-four studies (meta-analyses, reviews, original research) reveals insights into the gut microbiota-ASD relationship. While specific microbiota alterations are mixed, some trends emerge. ASD children exhibit increased Firmicutes (36-81%) and Pseudomonadota (78%) and decreased Bacteroidetes (56%). The Bacteroidetes to Firmicutes ratio tends to be lower (56%) compared to children without ASD, which correlates with behavioral and gastrointestinal abnormalities. Probiotics, particularly , , and strains, show promise in alleviating behavioral and gastrointestinal symptoms (66%). Microbiota transfer therapy (MTT) seems to have lasting benefits for the microbiota and symptoms in one longitudinal study. Prebiotics can potentially help with gastrointestinal and behavioral issues, needing further research for conclusive efficacy due to different interventions being used. This review highlights the gut microbiota-ASD interplay, offering potential therapeutic avenues for the gut-brain axis. However, study heterogeneity, small sample sizes, and methodological variations emphasize the need for comprehensive, standardized research. Future investigations may unveil complex mechanisms linking the gut microbiota to ASD, ultimately enhancing the quality of life for affected individuals.
Topics: Child; Humans; Autism Spectrum Disorder; Longitudinal Studies; Quality of Life; Microbiota; Gastrointestinal Microbiome; Gastrointestinal Diseases; Bacteroidetes; Firmicutes
PubMed: 38068995
DOI: 10.3390/ijms242316660 -
Nutrients Aug 2023Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder, the prevalence of which has increased in children and adolescents over the years. Studies point to... (Review)
Review
Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder, the prevalence of which has increased in children and adolescents over the years. Studies point to deficiency of trace elements as one of the factors involved in the etiology of the disorder, with zinc being one of the main trace elements investigated in individuals with ASD. The aim of this review is to summarize scientific evidence about the relationship between zinc status and ASD in children and adolescents. This review has been registered in the International Prospective Register of Systematic Reviews (registration number CRD42020157907). The methodological guidelines adopted were in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies were selected from an active investigation of the PubMed, Scopus, LILACS, and Google databases to search for observational studies. Fifty-two studies from twenty-two countries were included. The sample sizes ranged from 20 to 2635, and the participants ranged from 2 to 18 years old. Nine types of biological matrices were used, with hair, serum, and plasma being the most frequently used in the evaluation of zinc concentrations. Significant differences in zinc concentrations between the ASD and control groups were observed in 23 studies, of which 19 (36%) showed lower zinc concentrations in the ASD group. The classification of studies according to methodological quality resulted in high, moderate, and low quality in 10, 21, and 21 studies, respectively. In general, we did not observe a significant difference between zinc concentrations of children and adolescents with ASD compared to controls; however, studies point to an occurrence of lower concentrations of Zn in individuals with ASD. This review reveals that more prospective studies with greater methodological rigor should be conducted in order to further characterize this relation.
Topics: Humans; Adolescent; Child; Child, Preschool; Zinc; Trace Elements; Autism Spectrum Disorder; Prospective Studies; Databases, Factual
PubMed: 37630853
DOI: 10.3390/nu15163663 -
Brain, Behavior, and Immunity Nov 2023The aetiology of autism spectrum disorder (ASD) is complex and, partly, accounted by genetic factors. Nonetheless, the genetic underpinnings of ASD are poorly defined.... (Review)
Review
The aetiology of autism spectrum disorder (ASD) is complex and, partly, accounted by genetic factors. Nonetheless, the genetic underpinnings of ASD are poorly defined. The presence of immune dysregulations in autistic individuals, and their families, supports a role of the immune system and its genetic regulators. Albeit immune responses belong either to the innate or adaptive arms, the overall immune system genetics is broad, and encompasses a multitude of functionally heterogenous pathways which may have different influences on ASD. Hence, to gain insights on the immunogenetic underpinnings of ASD, we conducted a systematic literature review of previous immune genetic and transcription studies in ASD. We defined a list of immune genes relevant to ASD and explored their neuro-immune function. Our review confirms the presence of immunogenetic variability in ASD, accounted by inherited variations of innate and adaptive immune system genes and genetic expression changes in the blood and post-mortem brain of autistic individuals. Besides their immune function, the identified genes control neurodevelopment processes (neuronal and synaptic plasticity) and are highly expressed in pre/peri-natal periods. Hence, our synthesis bolsters the hypothesis that perturbation in immune genes may contribute to ASD by derailing the typical trajectory of neurodevelopment. Our review also helped identifying some of the limitations of prior immunogenetic research in ASD. Thus, alongside clarifying the neurodevelopment role of immune genes, we outline key considerations for future work into the aetiology of ASD and possible novel intervention targets.
PubMed: 37717669
DOI: 10.1016/j.bbi.2023.09.010