Parental report of the early development of children with regressive autism

Is autism a PIN1 deficiency syndrome? A proposed etiological role for glyphosate

Autism is a neurodevelopmental disorder, the prevalence of which has increased dramatically in the United States over the past two decades. It is characterized by stereotyped behaviors and impairments in social interaction and communication. In this paper, we present evidence that autism can be viewed as a PIN1 deficiency syndrome. Peptidyl-prolyl cis/trans isomerase, NIMA-Interacting 1 (PIN1) is a peptidyl-prolyl cis/trans isomerase, and it has widespread influences in biological organisms. Broadly speaking, PIN1 deficiency is linked to many neurodegenerative diseases, whereas PIN1 over-expression is linked to cancer. Death-associated protein kinase 1 (DAPK1) strongly inhibits PIN1, and the hormone melatonin inhibits DAPK1. Melatonin deficiency is strongly linked to autism. It has recently been shown that glyphosate exposure to rats inhibits melatonin synthesis as a result of increased glutamate release from glial cells and increased expression of metabotropic glutamate receptors. Glyphosate's inhibition of melatonin leads to a reduction in PIN1 availability in neurons. In this paper, we show that PIN1 deficiency can explain many of the unique morphological features of autism, including increased dendritic spine density, missing or thin corpus callosum, and reduced bone density. We show how PIN1 deficiency disrupts the functioning of powerful high-level signaling molecules, such as nuclear factor erythroid 2-related factor 2 (NRF2) and p53. Dysregulation of both of these proteins has been linked to autism. Severe depletion of glutathione in the brain resulting from chronic exposure to oxidative stressors and extracellular glutamate leads to oxidation of the cysteine residue in PIN1, inactivating the protein and further contributing to PIN1 deficiency. Impaired autophagy leads to increased sensitivity of neurons to ferroptosis. It is imperative that further research be conducted to experimentally validate whether the mechanisms described here take place in response to chronic glyphosate exposure and whether this ultimately leads to autism.

Case Report: A playful digital-analogical rehabilitative intervention to enhance working memory capacity and executive functions in a pre-school child with autism

Background

Autism Spectrum Disorder (ASD) is often associated with deficits in Working Memory Capacity (WMC) and Executive Functions (EFs), as early as the first years of life. Research has shown that, even young children with ASD, WMC and EF deficits can be effectively addressed through interventions employing digital and/or analogical tools. Early intervention is important because executive dysfunction can negatively impact on the quality of life, both of children and their families. However, very few studies have been carried out involving intervention with pre-schoolers with ASD. To fill this gap, we developed an intervention that promotes pre-schoolers' WMC and EFs by employing both digital apps and analogical playful activities. This study reports on the feasibility of this intervention, which was carried out in a rehabilitative context.

Methods

A male pre-schooler diagnosed with ASD was engaged in a total of 17 intervention sessions, all held in a clinical context, over a nine-week period. Outcomes were measured using a battery of pre- and post-treatment tasks focusing on WMC, EFs and receptive language. The clinician who administered the intervention made written observations and noted any improvements in the child's performance emerging from the digital and analogical activities.

Results

The pre- and post-test scores for the cognitive tasks revealed qualitative improvements in the following cognitive domains: (a) WMC in the language receptive domain; (b) updating in WMC; (c) inhibition, specifically concerning control of motor response; (d) receptive vocabulary. Furthermore, when monitoring the child's performance, the clinician noted improvement in almost all the playful activities. Particularly notable improvements were observed in interaction with the apps, which the child appeared to find very motivating.

Conclusion

This study supports feasibility of a playful digital-analogical intervention conducted by a clinician in a rehabilitation context to promote cognitive abilities in pre-schoolers with ASD. Further studies are needed to establish whether the intervention's effectiveness can be generalized to a broad sample of children with ASD.

Risk factors and clinical characteristics of autism spectrum disorder with regression in China

Autism spectrum disorder with regression (ASD-R) is characterized by the loss of previously acquired skills during the initial year of life. This study aimed to investigate the clinical characteristics, patterns of regression, and potential risk factors associated with ASD-R in the Chinese Han population. A case-control study was conducted between September 2020 and March 2022. A total of 186 children were enrolled, including 58 children with ASD-R, 70 with ASD without regression (ASD-NR), and 58 typically developing children. Demographic information, clinical characteristics, and potential risk factors related to ASD-R were assessed using a combination of questionnaires, interviews, and physician assessments. The results revealed that children with ASD-R exhibited more severe impairments in social communication and stereotyped behaviors compared with those with ASD-NR. Language regression, constituting 40% of cases within the ASD-R group, was found to be the most common type of regression. Furthermore, our analysis revealed that fever (OR = 4.01, 95% CI: 1.26-12.76) and diarrhea (OR = 6.32, 95% CI: 1.38-29.03) were identified as significant risk factors for ASD-R. These findings contribute to our understanding of the heterogeneity of ASD and highlight the importance of considering immune responses and gastrointestinal factors in the etiology of ASD-R.

Autistic clinical profiles, age at first concern, and diagnosis among children with autism spectrum disorder

Background

To explore the relationship between autistic clinical profiles and age at first concern and diagnosis among children with autism spectrum disorder. The clinical profiles included the severity of autism, cognition, adaptability, language development, and regression.

Methods

The multivariate linear regression model was used to examine the association of diagnostic age and first-concern age with autistic clinical profiles and with further stratification analysis.

Results

A total of 801 autistic children were included. Language delay and regression were associated with earlier diagnostic age (language delay: crudeβ: -0.80, 95%CI%: -0.92--0.68; regression: crudeβ: -0.21, 95%CI%: -0.43--0.00) and the age of first concern of autistic children (language delay: crudeβ: -0.55, 95%CI%: -0.65--0.45; regression: crudeβ: -0.17, 95%CI%: -0.34--0.00). After stratification by sex, language delay tended to be more associated with the earlier diagnostic age among boys (crudeβ: -0.85, 95%CI%: -0.98--0.72) than among girls (crudeβ: -0.46, 95%CI%: -0.77--0.16). After stratification by maternal education level or family income level, language delay was most associated with the earlier diagnostic age in autistic children from families with higher socioeconomic levels.

Conclusion

Language delay, rather than other symptoms, promoted an earlier diagnostic age. Among male autistic children or children from families with higher socioeconomic levels, language delay was most significantly associated with an earlier age of diagnosis. Cognitive delay, or adaptive delay, was associated with a later age at diagnosis and presented only in autistic children from families with lower socioeconomic levels. There may be sex or socioeconomic inequality in the diagnostic age for autistic children. More publicity and public education about the diversity of autistic symptoms are urgently needed in the future, especially for low-socioeconomic families.

Predictors of language regression and its association with subsequent communication development in children with autism

BACKGROUND

Language regression, broadly defined as the loss of acquired language skills in early childhood, is a distinctive feature of autism. Little is known about the factors underlying regression or the prognosis of children who exhibit regression. We examine potential predictors of language regression and test its association with language development in a prospective longitudinal sample of children with autism spectrum disorder (ASD) from diagnosis to age 10 years.

METHODS

We analysed data from Pathways in ASD, a prospective longitudinal study of 421 children enrolled around the time of an autism diagnosis between 2 and 5 years. Autism Diagnostic Interview-Revised data were available for 408 children, of whom 90 (22%) were classified as having language regression.

RESULTS

Demographic and other health factors including caregiver education, family income, child sex, reported seizures, and age of enrolment did not differ between children with and without language regression. Children with language regression walked earlier and attained first words sooner than those without regression. However, both groups attained phrase speech at comparable ages. Those with regression exhibited greater delays in expressive and receptive communication over the follow-up period, although this effect was attenuated when accounting for baseline differences in motor and cognitive ability. Overall, those with language regression continued to exhibit expressive but not receptive communication delay compared to those without regression. Communication trajectories were heterogeneous to age 10 years, irrespective of regression status.

CONCLUSIONS

Although language regression can be alarming, our findings confirm that its occurrence does not necessarily foreshadow worse developmental outcomes relative to those without regression. Although a discrepancy in age-equivalent communication skills may persist, this can be expected to be of less practical importance with rising average levels of skills. Future studies need to account for the significant variability in language trajectories by considering factors beyond developmental regression.

Pilot Study of Maternal Autoantibody-Related Autism

OBJECTIVE

The objective of this study was to investigate the presence of maternal autoantibody-related autism spectrum disorder (MAR-ASD) in 2 geographically distinct DBPNet clinical sites (Pennsylvania and Arkansas). MAR-ASD is a biologically defined subtype of ASD that is defined by the presence of autoantibodies specific to proteins in the fetal brain and present in approximately 20% of a Northern California sample but has not been studied in other states.

METHODS

Sixty-eight mothers of children with ASD were recruited from 2 DBPNet clinics and provided blood samples. Mothers also completed behavioral questionnaires about their children, and data from the child's clinical diagnostic assessment were abstracted.

RESULTS

The mean age of mothers was 38.5 ± 6.1 years, and the mean age of children was 8.3 ± 2.7 years. MAR-ASD was present in 24% of the sample and similar across sites. Children of +MAR mothers had more severe autism symptoms as measured by Autism Diagnostic Observation Schedule comparison scores (W = 3604; p < 0.001) and the Social Communication Questionnaire (W = 4556; p < 0.001). There were no differences in IQ, adaptive function, or aberrant behavior.

CONCLUSION

MAR-ASD is a subtype of autism that is present in similar frequencies across 3 states and related to autism severity.

Urine lactate concentration as a non-invasive screener for metabolic abnormalities: Findings in children with autism spectrum disorder and regression

There is increasing evidence that diseases caused by dysfunctional mitochondria (MD) are associated with autism spectrum disorder (ASD). A comprehensive meta-analysis showed that developmental regression was reported in half of the children with ASD and mitochondrial dysfunction which is much higher than in the general population of ASD. The aim of the present exploratory study was to determine lactate concentrations in urine of children with ASD, as a non-invasive large-scale screening method for metabolic abnormalities including mitochondrial dysfunction and its possible association with regression. First, clinical characteristics of MD were examined in 99 children (3–11 years) with ASD. Second, clinical characteristics of MD, severity of ASD and reported regression were compared between children with the 20% lowest lactate concentrations and those with the 20% highest lactate concentrations in urine. Third, clinical characteristics of MD and lactate concentration in urine were compared in children with (n = 37) and without (n = 62) reported regression. An association of urine lactate concentrations with mitochondrial dysfunction and regression could not be demonstrated in our large ASD cohort. However, since ASD children were reported by their parents to show a broad range of phenotypic characteristics of MD (e.g., gastro-intestinal and respiratory impairments), and lactate concentrations in urine are not always increased in individuals with MD, the presence of milder mitochondrial dysfunction cannot be excluded. Development of alternative biomarkers and their implementation in prospective studies following developmental trajectories of infants at elevated likelihood for ASD will be needed in the future to further unravel the association of ASD with mitochondrial dysfunction and eventually improve early detection.

Children with ASD and Communication Regression: Examining Pre-Loss Skills and Later Language Outcomes Through the Preschool Years

This study investigated receptive and expressive language outcomes in children with autism spectrum disorder (ASD) with and without a history of language/communication regression, employing three progressively less stringent definitions of regression. Data were derived from a large, longitudinal sample of children with ASD in which regression was assessed at approximately 30 months. Results indicated poorer receptive language and larger discrepancies between receptive and expressive language in the regression group than the group without regression at 44 months but not 66 months. Number of words used before loss predicted receptive language at 44 months. Overall, results suggest that a regression profile in ASD is associated with modest and transient impacts on language outcomes that are no longer discernable at school entry.

Bayonet-shaped language development in autism with regression: a retrospective study

Background

Language delay is one of the major referral criteria for an autism evaluation. Once an autism spectrum diagnosis is established, the language prognosis is among the main parental concerns. Early language regression (ELR) is observed by 10–50% of parents but its relevance to late language level and socio-communicative ability is uncertain. This study aimed to establish the predictive value of ELR on the progression of language development and socio-communicative outcomes to guide clinicians in addressing parents’ concerns at the time of diagnosis.

Methods

We used socio-communicative, language, and cognitive data of 2,047 autism spectrum participants from the Simons Simplex Collection, aged 4–18 years (mean = 9 years; SD = 3.6). Cox proportional hazard and logistic regression models were used to evaluate the effect of ELR on language milestones and the probability of using complex and flexible language, as defined by the choice of ADOS module at enrollment. Linear models were then used to evaluate the relationship of ELR and non-verbal IQ with socio-communicative and language levels.

Results

ELR is associated with earlier language milestones but delayed attainment of fluent, complex, and flexible language. However, this language outcome can be expected for almost all autistic children without intellectual disability at 18 years of age. It is mostly influenced by non-verbal IQ, not ELR. The language and socio-communicative level of participants with flexible language, as measured by the Vineland and ADOS socio-communicative subscales, was not affected by ELR.

Limitations

This study is based on a relatively coarse measure of ultimate language level and relies on retrospective reporting of early language milestones and ELR. It does not prospectively document the age at which language catches up, the relationship between ELR and other behavioral areas of regression, nor the effects of intervention.

Conclusions

For autistic individuals with ELR and a normal level of non-verbal intelligence, language development follows a “bayonet shape” trajectory: early first words followed by regression, a plateau with limited progress, and then language catch up.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-021-00444-8.

Characteristics, Early Development and Outcome of Parent-Reported Regression in Autism Spectrum Disorder

This study explored regression patterns in 100 children with ASD (3-11 years) using several approaches to enhance the validity of retrospective parent report. Both early development and outcome were examined in regression groups defined by 36 months age cut-off and two underlying empirical patterns based on type and onset age. Results over regression groups were generally consistent. During early development, children with regression showed a similar amount of social atypicalities and stereotyped behaviour as compared to children without regression. However, parents indicated less communication skills which could be a valuable predictor of regression. Development after regression was characterised by early language delay and more restricted and repetitive behaviour. The findings provide insight into the diagnosis and prognosis of regression in ASD.

Metal and essential element levels in hair and association with autism severity

BACKGROUND

Autism Spectrum Disorder (ASD) is a complex disorder with heterogeneous etiology and wide clinical severity which supports the needs of recognizing biological and clinical features in patient subsets. The present study aimed to understand possible associations between the hair levels of metals and essential elements and some specific features of ASD measured by the Autism Diagnostic Observation Schedule (ADOS) that represents the gold-standard instrument to objectively confirm ASD diagnosis.

METHODS

A cross-sectional study was performed in the province of Catania (Sicily, South Italy). Forty-eight subjects with ASD (70.8% male), aged from 2 to 17 years were studied. Metals (Li, Be, Al, Ni, As, Mo, Cd, Hg, U, Pb) and essential trace elements (Cr, Co, Mn, Zn, Cu, Se) were quantified in hair by inductively coupled plasma mass spectrometry analysis. Participants were characterized by measuring the severity of autism symptoms and cognitive levels.

RESULTS

A significant and positive correlation was found between hair metal burden (lead, aluminum, arsenic and cadmium levels) and severity of ASD symptoms (social communication deficits and repetitive, restrictive behaviors). Hair zinc level were inversely related with age while there was a negative, significant association between hair zinc level and severity of autistic symptoms (defective functional play and creativity and increase of stereotyped behavior). Lead, molybdenum and manganese hair levels were inversely correlated with cognitive level (full intelligence quotient) in ASD individuals.

CONCLUSIONS

The present study suggests the importance to combine metallomics analysis with pertinent disease features in ASD to identify potential environmental risk factors on an individual level possibly in the early developmental period.

Is Autism Inborn And Lifelong For Everyone?

Autism or autism spectrum disorder (ASD) is described as a lifelong condition with core behavioural symptoms appearing during infancy or early childhood. Genetic and other effects occurring during the earliest times of life are thought to play a significant contributory role to the presentation of autism, denoting that autism is typically seen as an innate or inborn condition. Such descriptions have, and continue to, define autism research and clinical practice. Inspection of the existing research literature, however, suggests that within the vast heterogeneity of autism, not everyone experiences autism in such a prescribed way. Various reports have observed the presentation of "acquired autism" following a period of typical development. Other findings have documented an abatement of clinically relevant autistic features and related comorbid pathology for some. Such reports offer important insights into the heterogeneity and complexity of autism.

Childhood disintegrative disorder and autism spectrum disorder: a systematic review

AIM

In an attempt to clarify the debate surrounding the diagnostic validity of childhood disintegrative disorder (CDD), we systematically reviewed its characteristics and compared it with autism spectrum disorder (ASD).

METHOD

Four databases were searched (PubMed, PsycINFO, Embase, and Web of Science). Included articles had participants with CDD, as defined by symptoms present in the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision and the International Classification of Diseases, 10th Revision. Comparison groups were those with ASD and ASD with regression. Case studies were excluded.

RESULTS

Twenty articles, comprising 96 participants with CDD (80 males, 16 females), were included. Most studies were cross-sectional. The prevalence of CDD was 1.1 to 9.2 per 100 000, with a mean age at regression of 3 years 2 months (SD 1y 1mo), with a range of 2 years to 7 years. In addition to core CDD symptoms, most had intellectual impairment, anxiety, challenging behaviours, and regressed in toileting skills. Participants with CDD and ASD shared core diagnostic and extra-diagnostic features. However, participants with CDD seemed to have more severe symptoms and a different symptom profile, including apparently typical development before regression, faster regression, more affective symptoms, and more global developmental deficit. Possible genetic and autoimmune neurobiological mechanisms were identified.

INTERPRETATION

There is limited high-quality evidence describing the aetiology and outcomes of CDD. However, given the qualitative and prognostic differences between ASD and CDD, we recommend that future diagnostic criteria should distinguish late-onset regression.

Changing conceptualizations of regression: What prospective studies reveal about the onset of autism spectrum disorder

Until the last decade, studies of the timing of early symptom emergence in autism spectrum disorder (ASD) relied upon retrospective methods. Recent investigations, however, are raising significant questions about the accuracy and validity of such data. Questions about when and how behavioral signs of autism emerge may be better answered through prospective studies, in which infants are enrolled near birth and followed longitudinally until the age at which ASD can be confidently diagnosed or ruled out. This review summarizes the results of recent studies that utilized prospective methods to study infants at high risk of developing ASD due to family history. Collectively, prospective studies demonstrate that the onset of ASD involves declines in the rates of key social and communication behaviors during the first years of life for most children. This corpus of literature suggests that regressive onset patterns occur much more frequently than previously recognized and may be the rule rather than the exception.

Nuclear Peroxisome Proliferator-Activated Receptors (PPARs) as Therapeutic Targets of Resveratrol for Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by defective social communication and interaction and restricted, repetitive behavior with a complex, multifactorial etiology. Despite an increasing worldwide prevalence of ASD, there is currently no pharmacological cure to treat core symptoms of ASD. Clinical evidence and molecular data support the role of impaired mitochondrial fatty acid oxidation (FAO) in ASD. The recognition of defects in energy metabolism in ASD may be important for better understanding ASD and developing therapeutic intervention. The nuclear peroxisome proliferator-activated receptors (PPAR) α, δ, and γ are ligand-activated receptors with distinct physiological functions in regulating lipid and glucose metabolism, as well as inflammatory response. PPAR activation allows a coordinated up-regulation of numerous FAO enzymes, resulting in significant PPAR-driven increases in mitochondrial FAO flux. Resveratrol (RSV) is a polyphenolic compound which exhibits metabolic, antioxidant, and anti-inflammatory properties, pointing to possible applications in ASD therapeutics. In this study, we review the evidence for the existing links between ASD and impaired mitochondrial FAO and review the potential implications for regulation of mitochondrial FAO in ASD by PPAR activators, including RSV.

Regression in autism spectrum disorder: A critical overview of retrospective findings and recommendations for future research

Historically, two onset patterns in autism spectrum disorder (ASD) were described: early onset of symptoms and regression in which one-third appear to show a loss of previously established skills in the second year of life. Since this phenomenon could represent a distinct ASD subtype and provide more insight into the etiology, diagnosis, and prognosis, many studies have compared these two groups. The present review discusses definitions, etiology, and methods used in research with a retrospective design and provides an overview of the results on early development and outcomes. However, retrospective research has not provided clear answers on regression as a distinct subtype of ASD and the historic division between early onset and regression does not seem to fit the empirical findings. Based on inconsistent results, future research on onset patterns in ASD needs to be more systematic on the definitions and methods used. Several recommendations to enhance the reliability of future retrospective results are discussed. The combination of a categorical and dimensional approach provides a new interesting framework.

Regression in autism spectrum disorder: Reconciling findings from retrospective and prospective research

The way in which the behavioral manifestations of autism spectrum disorder (ASD) emerge in infancy is variable. Regression-loss of previously acquired skills-occurs in a subset of children. However, the etiology and significance of regression remains unclear. Until recently, investigation of regression relied on retrospective report by parents or examination of home videos from early in life. However, home videos and retrospective report of the nature and timing of regression, and association with factors such as illness or immunization, is potentially subject to bias. The advent of prospective studies of infant siblings at familial high-risk of ASD has the potential to document regression as it occurs. Recent research has suggested that subtle loss of skills occurs in a larger proportion of children with ASD than previously assumed; however, there are few reports of clear-cut regressions, such as that involving dramatic loss of language and other established skills, in the prospective literature. This could be because of the following: clear-cut regression occurs less commonly than parent report suggests, study design limits the potential to detect regression, or there are differences between multiplex and simplex families in the rate of de novo genetic mutations and therefore regression risk. This review will bring together literature from retrospective and prospective research and attempt to reconcile diverging findings, with a specific focus on methodological issues. Changing conceptualizations of regression will be discussed, as well as etiological factors that may be associated with regression. The main challenges that need to be addressed to measure regression in prospective studies will be set out. Autism Research 2018, 11: 1602-1620. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Regression-a loss of previously established skills-occurs in a subset of children with ASD. Parental recall is not always accurate but studying younger siblings of children with ASD, 10-20% of whom will develop ASD, should make it possible to measure regression as it occurs. Clear-cut regression, like loss of language, has not often been reported in infant sibling studies, but recent research suggests that gradual loss of social engagement might be more common. This review looks at the evidence for regression from infant sibling studies and asks how study design affects the likelihood of capturing regression.

A Prospective Study of Environmental Exposures and Early Biomarkers in Autism Spectrum Disorder: Design, Protocols, and Preliminary Data from the MARBLES Study

BACKGROUND

Until recently, environmental factors in autism spectrum disorder (ASD) were largely ignored. Over the last decade, altered risks from lifestyle, medical, chemical, and other factors have emerged through various study designs: whole population cohorts linked to diagnostic and/or exposure-related databases, large case-control studies, and smaller cohorts of children at elevated risk for ASD.

OBJECTIVES

This study aimed to introduce the MARBLES (Markers of Autism Risk in Babies-Learning Early Signs) prospective study and its goals, motivate the enhanced-risk cohort design, describe protocols and main exposures of interest, and present initial descriptive results for the study population.

METHODS

Families having one or more previous child with ASD were contacted before or during a pregnancy, and once the woman became pregnant, were invited to enroll. Data and biological samples were collected throughout pregnancy, at birth, and until the child's third birthday. Neurodevelopment was assessed longitudinally. The study began enrolling in 2006 and is ongoing.

RESULTS

As of 30 June 2018, 463 pregnant mothers have enrolled. Most mothers ([Formula: see text]) were thirty years of age or over, including 7.9% who are fourty years of age or over. The sample includes 22% Hispanic and another 25% nonHispanic Black, Asian, or multiracial participants; 24% were born outside the United States. Retention is high: 84% of participants whose pregnancies did not end in miscarriage completed the study or are still currently active. Among children evaluated at 36 months of age, 24% met criteria for ASD, and another 25% were assessed as nonASD nontypical development.

CONCLUSION

Few environmental studies of ASD prospectively obtain early-life exposure measurements. The MARBLES study fills this gap with extensive data and specimen collection beginning in pregnancy and has achieved excellent retention in an ethnically diverse study population. The 24% familial recurrence risk is consistent with recent reported risks observed in large samples of siblings of children diagnosed with ASD. https://doi.org/10.1289/EHP535.

Onset patterns in autism: Variation across informants, methods, and timing

While previous studies suggested that regressive forms of onset were not common in autism spectrum disorder (ASD), more recent investigations suggest that the rates are quite high and may be under-reported using certain methods. The current study undertook a systematic investigation of how rates of regression differed by measurement method. Infants with (n = 147) and without a family history of ASD (n = 83) were seen prospectively for up to 7 visits in the first three years of life. Reports of symptom onset were collected using four measures that systematically varied the informant (examiner vs. parent), the decision type (categorical [regression absent or present] vs. dimensional [frequency of social behaviors]), and the timing of the assessment (retrospective vs. prospective). Latent class growth models were used to classify individual trajectories to see whether regressive onset patterns were infrequent or widespread within the ASD group. A majority of the sample was classified as having a regressive onset using either examiner (88%) or parent (69%) prospective dimensional ratings. Rates of regression were much lower using retrospective or categorical measures (from 29 to 47%). Agreement among different measurement methods was low. Declining trajectories of development, consistent with a regressive onset pattern, are common in children with ASD and may be more the rule than the exception. The accuracy of widely used methods of measuring onset is questionable and the present findings argue against their widespread use. Autism Res 2018, 11: 788-797. © 2018 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

This study examines different ways of measuring the onset of symptoms in autism spectrum disorder (ASD). The present findings suggest that declining developmental skills, consistent with a regressive onset pattern, are common in children with ASD and may be more the rule than the exception. The results question the accuracy of widely used methods of measuring symptom onset and argue against their widespread use.

Risk Assessment for Parents Who Suspect Their Child Has Autism Spectrum Disorder: Machine Learning Approach

Background

Parents are likely to seek Web-based communities to verify their suspicions of autism spectrum disorder markers in their child. Automated tools support human decisions in many domains and could therefore potentially support concerned parents.

Objective

The objective of this study was to test the feasibility of assessing autism spectrum disorder risk in parental concerns from Web-based sources, using automated text analysis tools and minimal standard questioning.

Methods

Participants were 115 parents with concerns regarding their child’s social-communication development. Children were 16- to 30-months old, and 57.4% (66/115) had a family history of autism spectrum disorder. Parents reported their concerns online, and completed an autism spectrum disorder-specific screener, the Modified Checklist for Autism in Toddlers-Revised, with Follow-up (M-CHAT-R/F), and a broad developmental screener, the Ages and Stages Questionnaire (ASQ). An algorithm predicted autism spectrum disorder risk using a combination of the parent's text and a single screening question, selected by the algorithm to enhance prediction accuracy.

Results

Screening measures identified 58% (67/115) to 88% (101/115) of children at risk for autism spectrum disorder. Children with a family history of autism spectrum disorder were 3 times more likely to show autism spectrum disorder risk on screening measures. The prediction of a child’s risk on the ASQ or M-CHAT-R was significantly more accurate when predicted from text combined with an M-CHAT-R question selected (automatically) than from the text alone. The frequently automatically selected M-CHAT-R questions that predicted risk were: following a point, make-believe play, and concern about deafness.

Conclusions

The internet can be harnessed to prescreen for autism spectrum disorder using parental concerns by administering a few standardized screening questions to augment this process.

Homogeneous Subgroups of Young Children with Autism Improve Phenotypic Characterization in the Study to Explore Early Development

The objective of this study was to identify homogenous classes of young children with autism spectrum disorder (ASD) to improve phenotypic characterization. Children were enrolled in the Study to Explore Early Development between 2 and 5 years of age. 707 children were classified with ASD after a comprehensive evaluation with strict diagnostic algorithms. Four classes of children with ASD were identified from latent class analysis: mild language delay with cognitive rigidity, mild language and motor delay with dysregulation, general developmental delay, and significant developmental delay with repetitive motor behaviors. We conclude that a four-class phenotypic model of children with ASD best describes our data and improves phenotypic characterization of young children with ASD. Implications for screening, diagnosis, and research are discussed.

Autism and attachment difficulties: Overlap of symptoms, implications and innovative solutions

This article explores overlap of symptoms between autism and attachment difficulties and suggests innovative solutions based on formulation. Currently, clinicians express difficulties in differentiating between these conditions contributing to misdiagnosis. Research into the prevalence of attachment difficulties among children with autism often fails to reflect detailed knowledge of attachment theory. Consequently, studies in this area employ questionable modifications to attachment measures and methods of analysis. The findings of such studies are confusing and inconsistent. Children with autism and their parents are, however, known to be at high risk of developing insecure attachment patterns. Clinical assessments based on formulation may be helpful in these cases, as they include consideration of developmental and relational factors contributing to symptom presentation. Research suggests that where parents of children with autism establish secure relationships with their children outcomes are improved. Consequently, interventions, which improve dyadic synchrony and sensitivity of parents, are likely to benefit families living with autism and attachment difficulties.

The Early Origins of Autism

Autism spectrum disorders (ASDs) are neurodevelopmental disorders whose core features of impaired social communication and atypical repetitive behaviors and/or restrictions in range of interests emerge in toddlerhood and carry significant implications at successive stages of development. The ability to reliably identify most cases of the condition far earlier than the average age of diagnosis presents a novel opportunity for early intervention, but the availability of such an intervention is disparate across US communities, and its impact is imperfectly understood. New research may transform the clinical approach to these conditions in early childhood.

Parent-reported patterns of loss and gain in communication in 1- to 2-year-old children are not unique to autism spectrum disorder

We compared loss and gain in communication from 1 to 2 years in children later diagnosed with autism spectrum disorder (n = 41), language impairment (n = 110) and in children with typical language development at 7 years (n = 831). Participants were selected from a prospective population cohort study of child language (the Early Language in Victoria Study). Parent-completed communication tools were used. As a group, children with autism spectrum disorder demonstrated slower median skill gain, with an increasing gap between trajectories compared to children with typical development and language impairment. A proportion from all groups lost skills in at least one domain (autism spectrum disorder (41%), language impairment (30%), typical development (26%)), with more children with autism spectrum disorder losing skills in more than one domain (autism spectrum disorder (47%), language impairment (15%, p = 0.0003), typical development (16%, p < 0.001)). Loss was most common for all groups in the domain of 'emotion and eye gaze' but with a higher proportion for children with autism spectrum disorder (27%; language impairment (12%, p = 0.03), typical development (14%, p = 0.03)). A higher proportion of children with autism spectrum disorder also lost skills in gesture (p = 0.01), sounds (p = 0.009) and understanding (p = 0.004) compared to children with typical development but not with language impairment. These findings add to our understanding of early communication development and highlight that loss is not unique to autism spectrum disorder.

Relevance of Neuroinflammation and Encephalitis in Autism

In recent years, many studies indicate that children with an autism spectrum disorder (ASD) diagnosis have brain pathology suggestive of ongoing neuroinflammation or encephalitis in different regions of their brains. Evidence of neuroinflammation or encephalitis in ASD includes: microglial and astrocytic activation, a unique and elevated proinflammatory profile of cytokines, and aberrant expression of nuclear factor kappa-light-chain-enhancer of activated B cells. A conservative estimate based on the research suggests that at least 69% of individuals with an ASD diagnosis have microglial activation or neuroinflammation. Encephalitis, which is defined as inflammation of the brain, is medical diagnosis code G04.90 in the International Classification of Disease, 10th revision; however, children with an ASD diagnosis are not generally assessed for a possible medical diagnosis of encephalitis. This is unfortunate because if a child with ASD has neuroinflammation, then treating the underlying brain inflammation could lead to improved outcomes. The purpose of this review of the literature is to examine the evidence of neuroinflammation/encephalitis in those with an ASD diagnosis and to address how a medical diagnosis of encephalitis, when appropriate, could benefit these children by driving more immediate and targeted treatments.

Emergence of autism spectrum disorder in children from simplex families: relations to parental perceptions of etiology

Current research describes a four-category scheme of Autism Spectrum Disorder (ASD) onset: early, regressive, plateau, delay + regression. To replicate prevalence of different onset types, ASD onset (per the Autism Diagnostic Interview--Revised) was examined in a large North American sample; for a subset, parents' causal beliefs were ascertained via the Revised Illness Perception Questionnaire to examine potential associations with ASD-onset types. Onset rates were similar across samples, with a slightly higher proportion of children in the subsample categorized with regression. Top-rated causes of ASD were genetics, brain structure, will of God, toxins in vaccines, and environmental pollution. Parents reporting regression more often believed that toxins in vaccines caused ASD. Influences on treatment selection and broader public-health ramifications are discussed.

Proteomic analysis of post mortem brain tissue from autism patients: evidence for opposite changes in prefrontal cortex and cerebellum in synaptic connectivity-related proteins

Background

Autism is a neurodevelopmental disorder characterized by impaired language, communication and social skills. Although genetic studies have been carried out in this field, none of the genes identified have led to an explanation of the underlying causes. Here, we have investigated molecular alterations by proteomic profiling of post mortem brain samples from autism patients and controls. The analysis focussed on prefrontal cortex and cerebellum as previous studies have found that these two brain regions are structurally and functionally connected, and they have been implicated in autism.

Methods

Post mortem prefrontal cortex and cerebellum samples from autism patients and matched controls were analysed using selected reaction monitoring mass spectrometry (SRM-MS). The main objective was to identify significantly altered proteins and biological pathways and to compare these across these two brain regions.

Results

Targeted SRM-MS resulted in identification of altered levels of proteins related to myelination, synaptic vesicle regulation and energy metabolism. This showed decreased levels of the immature astrocyte marker vimentin in both brain regions, suggesting a decrease in astrocyte precursor cells. Also, decreased levels of proteins associated with myelination and increased synaptic and energy-related proteins were found in the prefrontal cortex, indicative of increased synaptic connectivity. Finally, opposite directional changes were found for myelination and synaptic proteins in the cerebellum.

Conclusion

These findings suggest altered structural and/or functional connectivity in the prefrontal cortex and cerebellum in autism patients, as shown by opposite effects on proteins involved in myelination and synaptic function. Further investigation of these findings could help to increase our understanding of the mechanisms underlying autism relating to brain connectivity, with the ultimate aim of facilitating novel therapeutic approaches.

Brain-region-specific alterations of the trajectories of neuronal volume growth throughout the lifespan in autism

Several morphometric studies have revealed smaller than normal neurons in the neocortex of autistic subjects. To test the hypothesis that abnormal neuronal growth is a marker of an autism-associated global encephalopathy, neuronal volumes were estimated in 16 brain regions, including various subcortical structures, Ammon's horn, archicortex, cerebellum, and brainstem in 14 brains from individuals with autism 4 to 60 years of age and 14 age-matched control brains. This stereological study showed a significantly smaller volume of neuronal soma in 14 of 16 regions in the 4- to 8-year-old autistic brains than in the controls. Arbitrary classification revealed a very severe neuronal volume deficit in 14.3% of significantly altered structures, severe in 50%, moderate in 21.4%, and mild in 14.3% structures. This pattern suggests desynchronized neuronal growth in the interacting neuronal networks involved in the autistic phenotype. The comparative study of the autistic and control subject brains revealed that the number of structures with a significant volume deficit decreased from 14 in the 4- to 8-year-old autistic subjects to 4 in the 36- to 60-year-old. Neuronal volumes in 75% of the structures examined in the older adults with autism are comparable to neuronal volume in age-matched controls. This pattern suggests defects of neuronal growth in early childhood and delayed up-regulation of neuronal growth during adolescence and adulthood reducing neuron soma volume deficit in majority of examined regions. However, significant correction of neuron size but limited clinical improvements suggests that delayed correction does not restore functional deficits.

Challenges and opportunities in early identification and intervention for children at-risk for autism spectrum disorders

This response to Camarata (2014) both agrees and disagrees with a number of points relative to early identification and intervention for children with autism spectrum disorders (ASD). The authors, too, recognize the difficulties of identifying toddlers with ASD and the complexities of intervening with these children. It is, however, suggested that there are alternatives to choosing to wait until diagnoses for at-risk children are stable and it is believed that there are many potential benefits from intervening, even when stable diagnoses cannot be made at the time, but risk markers are present. Specifically, it is suggested that it is not necessary to differentially diagnose children in efforts to evaluate treatment effects and suggestions are provided for alternative methods. This commentary also acknowledges the importance of effective ASD screening tools, along with expert clinical opinion, to help identify these toddlers with and at-risk for ASD. Both the available literature from other researchers as well as the authors' own work in these areas are used to make these arguments.

Autism spectrum disorder, flea and tick medication, and adjustments for exposure misclassification: the CHARGE (CHildhood Autism Risks from Genetics and Environment) case-control study

BACKGROUND

The environmental contribution to autism spectrum disorders (ASD) is largely unknown, but household pesticides are receiving increased attention. We examined associations between ASD and maternally-reported use of imidacloprid, a common flea and tick treatment for pets.

METHODS

Bayesian logistic models were used to estimate the association between ASD and imidacloprid and to correct for potential differential exposure misclassification due to recall in a case control study of ASD.

RESULTS

Our analytic dataset included complete information for 262 typically developing controls and 407 children with ASD. Compared with exposure among controls, the odds of prenatal imidacloprid exposure among children with ASD were slightly higher, with an odds ratio (OR) of 1.3 (95% Credible Interval [CrI] 0.78, 2.2). A susceptibility window analysis yielded higher ORs for exposures during pregnancy than for early life exposures, whereas limiting to frequent users of imidacloprid, the OR increased to 2.0 (95% CI 1.0, 3.9).

CONCLUSIONS

Within plausible estimates of sensitivity and specificity, the association could result from exposure misclassification alone. The association between imidacloprid exposure and ASD warrants further investigation, and this work highlights the need for validation studies regarding prenatal exposures in ASD.

Evaluation of regression in autism spectrum disorder based on parental reports

BACKGROUND

Research indicates that some children with autism spectrum disorder (ASD) experience a developmental regression.

AIMS

The study examined the percentage of children with autism, pervasive developmental disorder (PDD), ASD, and Asperger syndrome (AS) who were considered to be delayed (D), regressed (R), or delayed and later regressed (DR) and examined any relationship with autism severity, time of onset, factors associated with onset, gastrointestinal (GI) symptoms, race, age, and gender.

MATERIALS AND METHODS

The study reviewed developmental and medical information based on parental reports of 135 children with a diagnosis of autism, PDD, ASD, or AS.

RESULTS

The number of children in the D group was 53 (39.2%) with 19 (14.1%) in the DR group and 63 (46.7%) in the R group. Thus, 82 children (60.7%) were reported to have R. In regard to onset of symptoms, there was a significant difference between the D and R groups as well as between the DR and R groups. The analyses showed that there was no significant relationship between age, gender, race, severity, or GI symptoms and membership in any group; D, DR, or R. The majority of parents reported that the regression was preceded by or was associated with vaccinations (57.3%) or another medically related event (11.0%).

CONCLUSIONS

The findings are consistent with previous research and reinforce our understanding of regression in those children with an ASD diagnosis.

Childhood disintegrative disorder: distinction from autistic disorder and predictors of outcome

Childhood disintegrative disorder, a rare, relentlessly progressive neurologic disorder, first described by Heller in 1908, remains a condition of great interest. It has long been debated whether it is a discrete disorder or simply a late-onset variant of childhood autism. We have studied 6 cases of childhood disintegrative disorder, collected over 8 years, and followed for 2.5 to 22 years (mean 8.6 years). Childhood disintegrative disorder begins later in life than autism, and following a period of entirely normal development; the regression is more global and more severe than in autism; seizures are more frequent than in autism, yet demonstrable organicity in childhood disintegrative disorder is decidedly rare. Lastly, the prognosis is usually much worse than in autism, but in those cases with neither seizures nor epileptiform activity on electroencephalography (EEG), the outcome may be more favorable. Childhood disintegrative disorder should be viewed as a condition distinct from childhood autism.

Patterns of skill attainment and loss in young children with autism

The purpose of this study was to extend the literature on the ontogeny of autism spectrum disorder (ASD) by examining early attainment and loss of specific sociocommunicative skills in children with autism (AUT; n = 125), pervasive developmental disorder not otherwise specified (PDD-NOS; n = 42), nonspectrum developmental delays (n = 46), and typical development (n = 31). The ages of skill attainment and loss were obtained from a caregiver interview. The findings indicated that children with AUT, PDD-NOS, and developmental delays diverged from typically developing children in attainment of sociocommunicative skills early in the first year of life. Loss of at least one skill was reported in a majority of children with AUT and PDD-NOS. Significant delays in attainment of skills were also reported in children who lost skills. The wide variation in skill attainment and loss reported across children indicates that symptom onset and regression may be best represented continuously, with at least some early delay and loss present for a great majority of children with ASD.

Thimerosal exposure and the role of sulfation chemistry and thiol availability in autism

Autism spectrum disorder (ASD) is a neurological disorder in which a significant number of the children experience a developmental regression characterized by a loss of previously acquired skills and abilities. Typically reported are losses of verbal, nonverbal, and social abilities. Several recent studies suggest that children diagnosed with an ASD have abnormal sulfation chemistry, limited thiol availability, and decreased glutathione (GSH) reserve capacity, resulting in a compromised oxidation/reduction (redox) and detoxification capacity. Research indicates that the availability of thiols, particularly GSH, can influence the effects of thimerosal (TM) and other mercury (Hg) compounds. TM is an organomercurial compound (49.55% Hg by weight) that has been, and continues to be, used as a preservative in many childhood vaccines, particularly in developing countries. Thiol-modulating mechanisms affecting the cytotoxicity of TM have been identified. Importantly, the emergence of ASD symptoms post-6 months of age temporally follows the administration of many childhood vaccines. The purpose of the present critical review is provide mechanistic insight regarding how limited thiol availability, abnormal sulfation chemistry, and decreased GSH reserve capacity in children with an ASD could make them more susceptible to the toxic effects of TM routinely administered as part of mandated childhood immunization schedules.

Evidence of neurodegeneration in autism spectrum disorder

Autism spectrum disorder (ASD) is a neurological disorder in which a significant number of children experience a developmental regression characterized by a loss of previously-acquired skills and abilities. Loss of neurological function in ASD, as observed in affected children who have regressed, can be explained as neurodegeneration. Although there is research evidence of neurodegeneration or progressive encephalopathy in ASD, the issue of neurodegeneration in ASD is still under debate. Evidence of neurodegeneration in the brain in ASD includes: (1) neuronal cell loss, (2) activated microglia and astrocytes, (3) proinflammatory cytokines, (4) oxidative stress, and (5) elevated 8-oxo-guanosine levels. The evidence from this review suggests that neurodegeneration underlies the loss of neurological function in children with ASD who have experienced regression and loss of previously acquired skills and abilities, and that research into treatments to address the issue of neurodegeneration in ASD are warranted.

The Study to Explore Early Development (SEED): a multisite epidemiologic study of autism by the Centers for Autism and Developmental Disabilities Research and Epidemiology (CADDRE) network

The Study to Explore Early Development (SEED), a multisite investigation addressing knowledge gaps in autism phenotype and etiology, aims to: (1) characterize the autism behavioral phenotype and associated developmental, medical, and behavioral conditions and (2) investigate genetic and environmental risks with emphasis on immunologic, hormonal, gastrointestinal, and sociodemographic characteristics. SEED uses a case-control design with population-based ascertainment of children aged 2-5 years with an autism spectrum disorder (ASD) and children in two control groups-one from the general population and one with non-ASD developmental problems. Data from parent-completed questionnaires, interviews, clinical evaluations, biospecimen sampling, and medical record abstraction focus on the prenatal and early postnatal periods. SEED is a valuable resource for testing hypotheses regarding ASD characteristics and causes.

Controversies in autism: is a broader model of social disorders needed?

This article examines the most significant, contradictory evidence pertaining to autism. The first section of the article includes reports of recovery from autism, data obtained from studies involving oxytocin, early deprivation, autism in preterm children, late-onset autism, and symptom overlap among ASD, social phobias and personality disorders. In the second section of the article, we offer a model that better incorporates current findings and address controversies that continue to surround ASD. We propose an umbrella term "social inhibition disorders" which integrates autism spectrum disorders and social phobias, as well as schizoid, schizotypal, and obsessive-compulsive personality disorders. It would also include "quasi-autism," which has been found in early deprivation studies, autism in preterm children, and cases of late-onset autism presenting after herpes encephalitis infection. Finally, we discuss suggestions for further research and clinical perspectives.

Age of first words predicts cognitive ability and adaptive skills in children with ASD

Acquiring useful language by age 5 has been identified as a strong predictor of positive outcomes in individuals with Autism Spectrum Disorders (ASD). This study examined the relationship between age of language acquisition and later functioning in children with ASD (n = 119). First word acquisition at a range of ages was probed for its relationship to cognitive ability and adaptive behaviors at 52 months. Results indicated that although producing first words predicted better outcome at every age examined, producing first words by 24 months was a particularly strong predictor of better outcomes. This finding suggests that the historic criterion for positive prognosis (i.e., "useful language by age 5") can be updated to a more specific criterion with an earlier developmental time point.

Medical conditions affect the outcome of early intervention in preschool children with autism spectrum disorders

The aim was to explore the frequency of genetic and other medical conditions, including epilepsy, in a population-based group of 208 preschool children with early diagnosis of Autism spectrum disorders (ASD) and to relate outcome at a 2-year follow-up to the co-existing medical findings. They had all received early intervention. The Vineland Adaptive Behaviour Scales (VABS-II) composite score served as the primary outcome measure. In the total group, 38/208 children (18 %) had a significant medical or genetic condition. Epilepsy was present in 6.3 % at the first assessment and in 8.6 % at follow-up and was associated with more severe intellectual impairment. A history of regression was reported in 22 %. Children with any medical/genetic condition, including epilepsy, as well as children with a history of regression had significantly lower VABS-II scores at the 2-year follow-up. Children with a medical/genetic condition, including epilepsy, had been diagnosed with ASD at an earlier age than those without such conditions, and early age at diagnosis also correlated negatively with adaptive functioning outcome. The results underscore the importance of considering medical/genetic aspects in all young children with ASD and the requirement to individualize and tailor interventions according to their specific needs.

Predicting developmental status from 12 to 24 months in infants at risk for Autism Spectrum Disorder: a preliminary report

The study examined whether performance profiles on individual items of the Toddler Module of the Autism Diagnostic Observation Schedule at 12 months are associated with developmental status at 24 months in infants at high and low risk for developing Autism Spectrum Disorder (ASD). A nonparametric decision-tree learning algorithm identified sets of 12-month predictors of developmental status at 24 months. Results suggest that identification of infants who are likely to exhibit symptoms of ASD at 24 months is complicated by variable patterns of symptom emergence. Fine-grained analyses linking specific profiles of strengths and deficits with specific patterns of symptom emergence will be necessary for further refinement of screening and diagnostic instruments for ASD in infancy.

Latent class analysis of early developmental trajectory in baby siblings of children with autism

BACKGROUND

Siblings of children with autism (sibs-A) are at increased genetic risk for autism spectrum disorders (ASD) and milder impairments. To elucidate diversity and contour of early developmental trajectories exhibited by sibs-A, regardless of diagnostic classification, latent class modeling was used.

METHODS

Sibs-A (N = 204) were assessed with the Mullen Scales of Early Learning from age 6 to 36 months. Mullen T scores served as dependent variables. Outcome classifications at age 36 months included: ASD (N = 52); non-ASD social/communication delay (broader autism phenotype; BAP; N = 31); and unaffected (N = 121). Child-specific patterns of performance were studied using latent class growth analysis. Latent class membership was then related to diagnostic outcome through estimation of within-class proportions of children assigned to each diagnostic classification.

RESULTS

A 4-class model was favored. Class 1 represented accelerated development and consisted of 25.7% of the sample, primarily unaffected children. Class 2 (40.0% of the sample), was characterized by normative development with above-average nonverbal cognitive outcome. Class 3 (22.3% of the sample) was characterized by receptive language, and gross and fine motor delay. Class 4 (12.0% of the sample), was characterized by widespread delayed skill acquisition, reflected by declining trajectories. Children with an outcome diagnosis of ASD were spread across Classes 2, 3, and 4.

CONCLUSIONS

Results support a category of ASD that involves slowing in early non-social development. Receptive language and motor development is vulnerable to early delay in sibs-A with and without ASD outcomes. Non-ASD sibs-A are largely distributed across classes depicting average or accelerated development. Developmental trajectories of motor, language, and cognition appear independent of communication and social delays in non-ASD sibs-A.

Reduced activity of protein kinase C in the frontal cortex of subjects with regressive autism: relationship with developmental abnormalities

Autism is a neurodevelopmental disorder with unknown etiology. In some cases, typically developing children regress into clinical symptoms of autism, a condition known as regressive autism. Protein kinases are essential for G-protein-coupled receptor-mediated signal transduction, and are involved in neuronal functions, gene expression, memory, and cell differentiation. Recently, we reported decreased activity of protein kinase A (PKA) in the frontal cortex of subjects with regressive autism. In the present study, we analyzed the activity of protein kinase C (PKC) in the cerebellum and different regions of cerebral cortex from subjects with regressive autism, autistic subjects without clinical history of regression, and age-matched control subjects. In the frontal cortex of subjects with regressive autism, PKC activity was significantly decreased by 57.1% as compared to age-matched control subjects (p = 0.0085), and by 65.8% as compared to non-regressed autistic subjects (p = 0.0048). PKC activity was unaffected in the temporal, parietal and occipital cortices, and in the cerebellum in both autism groups, i.e., regressive and non-regressed autism as compared to control subjects. These results suggest brain region-specific alteration of PKC activity in the frontal cortex of subjects with regressive autism. Further studies showed a negative correlation between PKC activity and restrictive, repetitive and stereotyped pattern of behavior (r= -0.084, p = 0.0363) in autistic individuals, suggesting involvement of PKC in behavioral abnormalities in autism. These findings suggest that regression in autism may be attributed, in part, to alterations in G-protein-coupled receptor-mediated signal transduction involving PKA and PKC in the frontal cortex.

Risk factors for autistic regression: results of an ambispective cohort study

A subgroup of children diagnosed with autism experience developmental regression featured by a loss of previously acquired abilities. The pathogeny of autistic regression is unknown, although many risk factors likely exist. To better characterize autistic regression and investigate the association between autistic regression and potential influencing factors in Chinese autistic children, we conducted an ambispective study with a cohort of 170 autistic subjects. Analyses by multiple logistic regression showed significant correlations between autistic regression and febrile seizures (OR = 3.53, 95% CI = 1.17-10.65, P = .025), as well as with a family history of neuropsychiatric disorders (OR = 3.62, 95% CI = 1.35-9.71, P = .011). This study suggests that febrile seizures and family history of neuropsychiatric disorders are correlated with autistic regression.

Brief report: symptom onset patterns and functional outcomes in young children with autism spectrum disorders

This study examined the relationship between onset status and current functioning using a recently proposed onset classification system in 272 young children with autism spectrum disorder (ASD). Participants were classified into one of the following groups, based on parent report using the Autism Diagnostic Interview--Revised: Early Onset (symptoms by 12 months, no loss), Delay + Regression (symptoms by 12 months plus loss), Plateau (no early symptoms or loss), and Regression (no early symptoms, followed by loss). Findings indicate that current functioning does not differ according to onset pattern, calling into question the use of onset categorizations for prognostic purposes in children with ASD.