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Journal of Child Psychology and... May 2016The etiology of Autism Spectrum Disorder (ASD) has been recently debated due to emerging findings on the importance of shared environmental influences. However, two... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The etiology of Autism Spectrum Disorder (ASD) has been recently debated due to emerging findings on the importance of shared environmental influences. However, two recent twin studies do not support this and instead re-affirm strong genetic effects on the liability to ASD, a finding consistent with previous reports. This study conducts a systematic review and meta-analysis of all twin studies of ASD published to date and explores the etiology along the continuum of a quantitative measure of ASD.
METHODS
A PubMed Central, Science Direct, Google Scholar, Web of Knowledge structured search conducted online, to identify all twin studies on ASD published to date. Thirteen primary twin studies were identified, seven were included in the meta-analysis by meeting Systematic Recruitment criterion; correction for selection and ascertainment strategies, and applied prevalences were assessed for these studies. In addition, a quantile DF extremes analysis was carried out on Childhood Autism Spectrum Test scores measured in a population sample of 6,413 twin pairs including affected twins.
RESULTS
The meta-analysis correlations for monozygotic twins (MZ) were almost perfect at .98 (95% Confidence Interval, .96-.99). The dizygotic (DZ) correlation, however, was .53 (95% CI .44-.60) when ASD prevalence rate was set at 5% (in line with the Broad Phenotype of ASD) and increased to .67 (95% CI .61-.72) when applying a prevalence rate of 1%. The meta-analytic heritability estimates were substantial: 64-91%. Shared environmental effects became significant as the prevalence rate decreased from 5-1%: 07-35%. The DF analyses show that for the most part, there is no departure from linearity in heritability.
CONCLUSIONS
We demonstrate that: (a) ASD is due to strong genetic effects; (b) shared environmental effects become significant as a function of lower prevalence rate; (c) previously reported significant shared environmental influences are likely a statistical artefact of overinclusion of concordant DZ twins.
Topics: Autism Spectrum Disorder; Diseases in Twins; Genetic Predisposition to Disease; Humans
PubMed: 26709141
DOI: 10.1111/jcpp.12499 -
Neuroscience and Biobehavioral Reviews Oct 2021Post-mortem studies allow for the direct investigation of brain tissue in those with autism and related disorders. Several review articles have focused on aspects of... (Review)
Review
Post-mortem studies allow for the direct investigation of brain tissue in those with autism and related disorders. Several review articles have focused on aspects of post-mortem abnormalities but none has brought together the entire post-mortem literature. Here, we systematically review the evidence from post-mortem studies of autism, and of related disorders that present with autistic features. The literature consists of a small body of studies with small sample sizes, but several remarkably consistent findings are evident. Cortical layering is largely undisturbed, but there are consistent reductions in minicolumn numbers and aberrant myelination. Transcriptomics repeatedly implicate abberant synaptic, metabolic, proliferation, apoptosis and immune pathways. Sufficient replicated evidence is available to implicate non-coding RNA, aberrant epigenetic profiles, GABAergic, glutamatergic and glial dysfunction in autism pathogenesis. Overall, the cerebellum and frontal cortex are most consistently implicated, sometimes revealing distinct region-specific alterations. The literature on related disorders such as Rett syndrome, Fragile X and copy number variations (CNVs) predisposing to autism is particularly small and inconclusive. Larger studies, matched for gender, developmental stage, co-morbidities and drug treatment are required.
Topics: Autism Spectrum Disorder; Autistic Disorder; Autopsy; Brain; Cerebellum; DNA Copy Number Variations; Humans
PubMed: 34273379
DOI: 10.1016/j.neubiorev.2021.07.014 -
Complementary Therapies in Clinical... Feb 2023and purpose Individuals with autism spectrum disorder (ASD) experience difficulty with communication, learning, behaviour, and social interactions. Animal-assisted... (Review)
Review
BACKGROUND
and purpose Individuals with autism spectrum disorder (ASD) experience difficulty with communication, learning, behaviour, and social interactions. Animal-assisted therapy (AAT) is a growing alternative and complementary therapy for ASD. This review aims to investigate the effectiveness of AAT for children and adolescents with ASD in the domains of cognitive, social, emotional, behavioural, and physical.
METHODS
A systematic search of databases (Medline, Emcare, Embase, Cochrane Library, PsycINFO, PsycARTICLES, Scopus, ERIC and OTseeker) was conducted in March 2022. Grey literature was also explored which included searching Trove database and the first 10 pages of Google, as well as pearling reference lists of included studies. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The methodological quality of the included studies was assessed using a modified Joanna Briggs Institute Review Form for Randomised Controlled Trials. A descriptive synthesis was undertaken due to heterogeneity within the evidence base.
RESULTS
Seven randomised controlled/clinical controlled trials with moderate methodological quality were included in this review. Overall, participation in AAT identified positive trends in the cognitive, social, emotional, behavioural, and physical domains. Despite the positive outcomes, implementation of AAT should be taken with caution as there are currently no standardised frameworks due to heterogeneity within the intervention protocols and outcome measures.
CONCLUSION
AAT may have positive effects across a multitude of outcomes in the management of ASD for children and adolescents. However, the current literature has considerable methodological concerns which should be addressed by future research.
Topics: Animals; Child; Humans; Autism Spectrum Disorder; Animal Assisted Therapy; Communication; Outcome Assessment, Health Care; Emotions
PubMed: 36599281
DOI: 10.1016/j.ctcp.2022.101719 -
The Australian and New Zealand Journal... Feb 2023Autism spectrum disorders and personality disorders are spectrum conditions with shared clinical features. Despite similarities, previous attempts to synthesise... (Review)
Review
OBJECTIVES
Autism spectrum disorders and personality disorders are spectrum conditions with shared clinical features. Despite similarities, previous attempts to synthesise literature on co-existing prevalence and shared traits have employed a unidirectional focus, assessing personality characteristics of individuals with an autism spectrum disorder diagnosis. Here, we assess the prevalence of autism spectrum disorder diagnosis and/or traits among persons diagnosed with a personality disorder.
METHODS
We systematically reviewed the English-language literature following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, according to a pre-registered protocol (PROSPERO: CRD 42021264106). Peer-reviewed quantitative studies reporting the prevalence of autism spectrum disorder diagnosis or traits in persons with an established personality disorder diagnosis were included. Studies were critically appraised using the Appraisal tool for Cross-Sectional Studies.
RESULTS
Fifteen studies were identified, including 72,902 participants (median: 48, interquartile range: 30-77). Diagnoses included borderline, schizotypal and obsessive-compulsive personality disorders, and cohorts with unspecified personality disorder diagnoses. There was significant heterogeneity in diagnostic methodology and assessment tools used. We identified preliminary evidence of an increased prevalence of co-existing autism spectrum disorder diagnosis and traits among those diagnosed with a personality disorder, although significant limitations of the literature were identified.
CONCLUSION
Our research suggests clinicians should consider conducting a careful developmental assessment when assessing service-users with possible or confirmed personality disorder. Future research directions may include larger studies featuring clinical control groups, an exploration of shared and differentiating behavioural-cognitive features of the two conditions, and investigation into potentially shared aetiological factors. Research investigating demographic factors that may contribute to potential diagnostic overshadowing would also be welcomed.
Topics: Humans; Adult; Adolescent; Autism Spectrum Disorder; Prevalence; Cross-Sectional Studies; Personality Disorders; Obsessive-Compulsive Disorder
PubMed: 35986511
DOI: 10.1177/00048674221114603 -
Nutrients Mar 2023Many studies have explored the efficacy of probiotics on autism spectrum disorder (ASD) in children, but there is no consensus on the curative effect. This systematic... (Meta-Analysis)
Meta-Analysis Review
Many studies have explored the efficacy of probiotics on autism spectrum disorder (ASD) in children, but there is no consensus on the curative effect. This systematic review and meta-analysis aimed to comprehensively investigate whether probiotics could improve behavioral symptoms in children with ASD. A systematic database search was conducted and a total of seven studies were included in the meta-analysis. We found a nonsignificant overall effect size of probiotics on behavioral symptoms in children with ASD (SMD = -0.24, 95% CI: -0.60 to 0.11, = 0.18). However, a significant overall effect size was found in the subgroup of the probiotic blend (SMD = -0.42, 95% CI: -0.83 to -0.02, = 0.04). Additionally, these studies provided limited evidence for the efficacy of probiotics due to their small sample sizes, a shorter intervention duration, different probiotics used, different scales used, and poor research quality. Thus, randomized, double-blind, and placebo-controlled studies following strict trial guidelines are needed to precisely demonstrate the therapeutic effects of probiotics on ASD in children.
Topics: Humans; Child; Autism Spectrum Disorder; Probiotics; Randomized Controlled Trials as Topic
PubMed: 36986145
DOI: 10.3390/nu15061415 -
The American Journal of Occupational... 2019The purpose of this systematic review was to evaluate the evidence for the effectiveness of parent-mediated interventions on occupational performance of children with...
OBJECTIVE
The purpose of this systematic review was to evaluate the evidence for the effectiveness of parent-mediated interventions on occupational performance of children with autism spectrum disorder (ASD).
METHOD
We conducted a search of academic databases using terms such as autism spectrum disorder, parent, caregiver, and intervention. Five hundred eighty-two articles were reviewed, and 109 were selected for full-text review. The final analysis included 13 articles.
RESULTS
Strong evidence was found for the efficacy of parent-mediated intervention for increasing child joint attention. Moderate evidence was found for the improvement of language scores, expressive language, nonverbal communication, initiation and response to interaction, behavior, play, adaptive functioning, ASD symptoms, and social communication.
CONCLUSION
This systematic review suggests that parent-mediated interventions for children with ASD can improve various aspects of communication and ASD symptoms, with emerging support for occupational performance. Occupational therapy practitioners are well suited to facilitate these interventions to support families with children with autism.
Topics: Adult; Autism Spectrum Disorder; Autistic Disorder; Child; Communication; Humans; Parent-Child Relations; Parents
PubMed: 31120831
DOI: 10.5014/ajot.2019.030015 -
Stem Cell Reviews and Reports Jan 2022Assess the safety and efficacy of upcoming stem cell treatments and analyze their effects on the cognitive and behavioral impairments in patients diagnosed with autism. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Assess the safety and efficacy of upcoming stem cell treatments and analyze their effects on the cognitive and behavioral impairments in patients diagnosed with autism.
METHODS
We included controlled and noncontrolled, randomized and non-randomized trials evaluating stem cell therapy as a treatment in patients with autism spectrum disorder compared to placebo or without comparator.
DATA SOURCES
Scopus, Web of Science, MEDLINE and EMBASE. Risk of bias was assessed using Cochrane's Risk of Bias tool and the NIH's Quality Assessment Tool for Studies With No Control Group.
RESULTS
Eleven trials including 461 patients proved eligible. ABC scale meta-analysis showed a mean raw of -11.97 in the intervention groups (95 % CI -91.45 to 67.52, p < 0.01). CARS scale reported a mean raw of -9.08 (95 % CI -15.43 to -2.73, p < 0.01). VABS scale was reported by their domains: communication domain reported a mean raw of 2.69 (95 % CI 1.30 to 4.08, p = 0.92); daily living domain, 1.99 (95 % CI 0.83 to 3.15, p = 0.51); motor domain, 1.06 (95 % CI -0.37 to 2.48, p = 0.20); socialization domain, 3.09 (95 % CI 1.71 to 4.48, p = 0.61); adaptive behavior domain, 2.10 (95 % CI 1.04 to 3.16, p = 0.36). Furthermore, the most common side effects reported included fever, hyperactivity, vomit, headache, and aggressiveness; no serious adverse events were reported.
CONCLUSIONS
The body of evidence suggests that stem cell therapy significantly improves scales in patients with autism spectrum disorder, hence, future studies should help us have more confidence in the results. We found no serious adverse events related to the stem cell therapy.
Topics: Autism Spectrum Disorder; Cell- and Tissue-Based Therapy; Humans
PubMed: 34515938
DOI: 10.1007/s12015-021-10257-0 -
Journal of Autism and Developmental... Oct 2018This review (Prospero Registration Number: CRD42017057915) aimed to systematically identify and summarize existing research on the relationship between additional... (Meta-Analysis)
Meta-Analysis Review
The Association Between Emotional and Behavioral Problems in Children with Autism Spectrum Disorder and Psychological Distress in Their Parents: A Systematic Review and Meta-analysis.
This review (Prospero Registration Number: CRD42017057915) aimed to systematically identify and summarize existing research on the relationship between additional emotional and behavioral problems (EBP) in children with autism, and parenting stress (PS) and mental health problems (MHP) in their parents. Sixty-seven studies met criteria for inclusion in the review, 61 of which were included in the meta-analysis. Pooled correlation coefficients were in the low to moderate range ([Formula: see text]). Some evidence for moderation by measurement characteristics was found. Narrative review of concurrent adjusted associations showed some evidence for shared relationships with other factors, most notably ASD severity and parent perception of own parenting. Longitudinal studies showed mixed evidence for bidirectional predictive relationships between child EBP and parent psychological distress variables.
Topics: Adolescent; Autism Spectrum Disorder; Child; Child Behavior Disorders; Child, Preschool; Emotions; Female; Humans; Longitudinal Studies; Male; Parenting; Parents; Problem Behavior; Stress, Psychological; Young Adult
PubMed: 29777471
DOI: 10.1007/s10803-018-3605-y -
European Child & Adolescent Psychiatry Sep 2017Somatic disorders occur more often in adult psychiatric patients than in the general adult population. However, in child and adolescent psychiatry this association is... (Review)
Review
Somatic disorders occur more often in adult psychiatric patients than in the general adult population. However, in child and adolescent psychiatry this association is unclear, mainly due to a lack of integration of existing data. To address this issue, we here present a systematic review on medical comorbidity in the two major developmental disorders autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) and formulate clinical recommendations. The literature was searched using the PubMed and PsycINFO databases (2000-1 May 2016) with the keywords "[((child and adolescent) AND (Autism OR Attention Deficit Hyperactivity Disorder* OR ADHD)) AND ("Cardiovascular Diseases" [Mesh] OR "Endocrine System Diseases" [Mesh] OR "Immune System Diseases" [Mesh] OR "Neurobehavioral Manifestations" [Mesh] OR "Gastrointestinal Disorders" [Mesh] OR Somatic OR Autoimmune disease OR Nervous system disease OR Infection OR Infectious disease)]. Two raters independently assessed the quality of the eligible studies. The initial search identified 5278 articles. Based on inclusion and exclusion criteria 104 papers were selected and subsequently subjected to a quality control. This quality was assessed according to a standardized and validated set of criteria and yielded 29 studies for inclusion. This thorough literature search provides an overview of relevant articles on medical comorbidity in ADHD and/or ASD, and shows that medical disorders in these children and adolescents appear to be widespread. Those who work with children with ASD and/or ADHD should be well aware of this and actively promote routine medical assessment. Additionally, case-control studies and population-based studies are needed to provide reliable prevalence estimates. Future studies should furthermore focus on a broader evaluation of medical disorders in children and adolescents with ADHD and/or ASD to improve treatment algorithm in this vulnerable group.
Topics: Adolescent; Attention Deficit Disorder with Hyperactivity; Autism Spectrum Disorder; Child; Child, Preschool; Comorbidity; Cross-Sectional Studies; Female; Humans; Male
PubMed: 28674760
DOI: 10.1007/s00787-017-1020-0 -
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