Showing papers on "Autism published in 2001"
TL;DR: The Autism-Spectrum Quotient is a valuable instrument for rapidly quantifying where any given individual is situated on the continuum from autism to normality, and its potential for screening for autism spectrum conditions in adults of normal intelligence remains to be fully explored.
Abstract: Currently there are no brief, self-administered instruments for measuring the degree to which an adult with normal intelligence has the traits associated with the autistic spectrum. In this paper, we report on a new instrument to assess this: the Autism-Spectrum Quotient (AQ). Individuals score in the range 0-50. Four groups of subjects were assessed: Group 1: 58 adults with Asperger syndrome (AS) or high-functioning autism (HFA); Group 2: 174 randomly selected controls. Group 3: 840 students in Cambridge University; and Group 4: 16 winners of the UK Mathematics Olympiad. The adults with AS/HFA had a mean AQ score of 35.8 (SD = 6.5), significantly higher than Group 2 controls (M = 16.4, SD = 6.3). 80% of the adults with AS/HFA scored 32+, versus 2% of controls. Among the controls, men scored slightly but significantly higher than women. No women scored extremely highly (AQ score 34+) whereas 4% of men did so. Twice as many men (40%) as women (21%) scored at intermediate levels (AQ score 20+). Among the AS/HFA group, male and female scores did not differ significantly. The students in Cambridge University did not differ from the randomly selected control group, but scientists (including mathematicians) scored significantly higher than both humanities and social sciences students, confirming an earlier study that autistic conditions are associated with scientific skills. Within the sciences, mathematicians scored highest. This was replicated in Group 4, the Mathematics Olympiad winners scoring significantly higher than the male Cambridge humanities students. 6% of the student sample scored 32+ on the AQ. On interview, 11 out of 11 of these met three or more DSM-IV criteria for AS/HFA, and all were studying sciences/mathematics, and 7 of the 11 met threshold on these criteria. Test-retest and interrater reliability of the AQ was good. The AQ is thus a valuable instrument for rapidly quantifying where any given individual is situated on the continuum from autism to normality. Its potential for screening for autism spectrum conditions in adults of normal intelligence remains to be fully explored.
4,988 citations
TL;DR: The Revised Eyes Test has improved power to detect subtle individual differences in social sensitivity and was inversely correlated with the Autism Spectrum Quotient (the AQ), a measure of autistic traits in adults of normal intelligence.
Abstract: In 1997 in this Journal we published the ‘‘Reading the Mind in the Eyes’’ Test, as a measure of adult ‘‘mentalising’’. Whilst that test succeeded in discriminating a group of adults with Asperger syndrome (AS) or high-functioning autism (HFA) from controls, it suered from several psychometric problems. In this paper these limitations are rectified by revising the test. The Revised Eyes Test was administered to a group of adults with AS or HFA (N fl 15) and again discriminated these from a large number of normal controls (N fl 239) drawn from dierent samples. In both the clinical and control groups the Eyes Test was inversely correlated with the Autism Spectrum Quotient (the AQ), a measure of autistic traits in adults of normal intelligence. The Revised Eyes Test has improved power to detect subtle individual dierences in social sensitivity.
4,858 citations
TL;DR: Six items pertaining to social relatedness and communication were found to have the best discriminability between children diagnosed with and without autism/PDD.
Abstract: Autism, a severe disorder of development, is difficult to detect in very young children. However, children who receive early intervention have improved long-term prognoses. The Modified Checklist for Autism in Toddlers (M-CHAT), consisting of 23 yes/no items, was used to screen 1,293 children. Of the 58 children given a diagnostic/developmental evaluation, 39 were diagnosed with a disorder on the autism spectrum. Six items pertaining to social relatedness and communication were found to have the best discriminability between children diagnosed with and without autism/PDD. Cutoff scores were created for the best items and the total checklist. Results indicate that the M-CHAT is a promising instrument for the early detection of autism.
1,456 citations
TL;DR: Hyperplasia was present in cerebral gray matter and cerebral and cerebellar white matter in early life in patients with autism and normal regulation of brain growth in autism results in early overgrowth followed by abnormally slowed growth.
Abstract: Objective: To quantify developmental abnormalities in cerebral and cerebellar volume in autism. Methods: The authors studied 60 autistic and 52 normal boys (age, 2 to 16 years) using MRI. Thirty autistic boys were diagnosed and scanned when 5 years or older. The other 30 were scanned when 2 through 4 years of age and then diagnosed with autism at least 2.5 years later, at an age when the diagnosis of autism is more reliable. Results: Neonatal head circumferences from clinical records were available for 14 of 15 autistic 2- to 5-year-olds and, on average, were normal (35.1 ± 1.3 cm versus clinical norms: 34.6 ± 1.6 cm), indicative of normal overall brain volume at birth; one measure was above the 95th percentile. By ages 2 to 4 years, 90% of autistic boys had a brain volume larger than normal average, and 37% met criteria for developmental macrencephaly. Autistic 2- to 3-year-olds had more cerebral (18%) and cerebellar (39%) white matter, and more cerebral cortical gray matter (12%) than normal, whereas older autistic children and adolescents did not have such enlarged gray and white matter volumes. In the cerebellum, autistic boys had less gray matter, smaller ratio of gray to white matter, and smaller vermis lobules VI–VII than normal controls. Conclusions: Abnormal regulation of brain growth in autism results in early overgrowth followed by abnormally slowed growth. Hyperplasia was present in cerebral gray matter and cerebral and cerebellar white matter in early life in patients with autism.
1,391 citations
TL;DR: There was significant heterogeneity in their language skills, although across all the children, articulation skills were spared and the profile of performance across the standardised measures for the languageimpaired children with autism was similar to the profile that defines the disorder specific language impairment (or SLI).
Abstract: Autism involves primary impairments in both language and communication, yet in recent years the main focus of research has been on the communicative deficits that define the population. The study reported in this paper investigated language functioning in a group of 89 children diagnosed with autism using the ADI-R, and meeting DSM-IV criteria. The children, who were between 4- and 14- years-old were administered a battery of standardized language tests tapping phonological, lexical, and higher-order language abilities. The main findings were that among the children with autism there was significant heterogeneity in their language skills, although across all the children, articulation skills were spared. Different subgroups of children with autism were identified on the basis on their performance on the language measures. Some children with autism have normal language skills; for other children, their language skills are significantly below age expectations. The profile of performance across the standardized measures for the language-impaired children with autism was similar to the profile that defines the disorder specific language impairment (or SLI). The implications of this language impaired subgroup in autism for understanding the genetics and definition of both autism and SLI are discussed.
941 citations
TL;DR: It is suggested that in order for sophisticated cortical neuronal systems have evolved in which MNs function as key elements, early developmental failures of MN systems are likely to result in a consequent cascade of developmental impairments characterised by the clinical syndrome of autism.
925 citations
TL;DR: It appears that, as compared with normal individuals, autistic individuals 'see' faces utilizing different neural systems, with each patient doing so via a unique neural circuitry, suggesting that experiential factors do indeed play a role in the normal development of the FFA.
Abstract: Processing the human face is at the focal point of most social interactions, yet this simple perceptual task is difficult for individuals with autism, a population that spends limited amounts of time engaged in face-to-face eye contact or social interactions in general. Thus, the study of face processing in autism is not only important because it may be integral to understanding the social deficits of this disorder, but also, because it provides a unique opportunity to study experiential factors related to the functional specialization of normal face processing. In short, autism may be one of the only disorders where affected individuals spend reduced amounts of time engaged in face processing from birth. Using functional MRI, haemodynamic responses during a face perception task were compared between adults with autism and normal control subjects. Four regions of interest (ROIs), the fusiform gyrus (FG), inferior temporal gyrus, middle temporal gyrus and amygdala were manually traced on non-spatially normalized images and the percentage ROI active was calculated for each subject. Analyses in Talairach space were also performed. Overall results revealed either abnormally weak or no activation in FG in autistic patients, as well as significantly reduced activation in the inferior occipital gyrus, superior temporal sulcus and amygdala. Anatomical abnormalities, in contrast, were present only in the amygdala in autistic patients, whose mean volume was significantly reduced as compared with normals. Reaction time and accuracy measures were not different between groups. Thus, while autistic subjects could perform the face perception task, none of the regions supporting face processing in normals were found to be significantly active in the autistic subjects. Instead, in every autistic patient, faces maximally activated aberrant and individual-specific neural sites (e.g. frontal cortex, primary visual cortex, etc.), which was in contrast to the 100% consistency of maximal activation within the traditional fusiform face area (FFA) for every normal subject. It appears that, as compared with normal individuals, autistic individuals 'see' faces utilizing different neural systems, with each patient doing so via a unique neural circuitry. Such a pattern of individual-specific, scattered activation seen in autistic patients in contrast to the highly consistent FG activation seen in normals, suggests that experiential factors do indeed play a role in the normal development of the FFA.
867 citations
TL;DR: The identification of chromosomal abnormalities and Mendelian syndromes among individuals with autism, in conjunction with data from genome screens and candidate-gene studies, has helped to refine the view of the complex genetics that underlies autism spectrum conditions.
Abstract: Since autism was first recognized as a disorder in 1943, speculation about its aetiology has ranged from biological to psychological and back again. After twin studies during the 1970s and 1980s yielded unequivocal evidence for a genetic component, aetiological research in autism began to focus primarily on uncovering the genetic mechanisms involved. The identification of chromosomal abnormalities and Mendelian syndromes among individuals with autism, in conjunction with data from genome screens and candidate-gene studies, has helped to refine the view of the complex genetics that underlies autism spectrum conditions.
798 citations
TL;DR: The empirical evidence for the involvement of genetic risk factors in infantile autism is reviewed systematically for the first time to establish a causal link between genes and autism.
Abstract: Objective: To review systematically the empirical evidence for the involvement of genetic risk factors in infantile autism.
Method: We aimed at including all relevant papers written in English. We conducted a Medline search in September 2000. In addition we searched the reference lists of related papers.
Results: A relatively small number of reports including family and twin studies, comorbidity, cytogenetic and molecular genetic studies were reviewed.
Conclusion: As well family, twin, cytogenetic and molecular genetic studies supported the importance of genetic risk factors in infantile autism. In most individual cases probably at least a few gene variants simultaneously determine the genetic risk. Presently the most interesting chromosome regions concerning the aetiology of autism are chromosomes 7q31–35, 15q11–13 and 16p13.3 which have been suggested by different lines of genetic research.
697 citations
TL;DR: Parental depression was assessed using the Beck Depression Inventory (BDI) in 216 families with children with autism and/or intellectual disability (ID), and in 214 control families and single mothers of children with disabilities were found to be more vulnerable to severe depression.
Abstract: Parental depression was assessed using the Beck Depression Inventory (BDI) in 216 families with children with autism and/or intellectual disability (ID), and in 214 control families. Mothers with children with autism had higher depression scores (mean = 11.8) than mothers of children with ID without autism (mean = 9.2), who in turn, had higher depression scores than fathers of children with autism (mean = 6.2), fathers of children with ID without autism (mean = 5.0), and control mothers (mean = 5.0) and fathers (mean = 4.1). Forty-five per cent of mothers with children with ID without autism and 50% of mothers with children with autism had elevated depression scores (BDI > 9), compared to 15-21% in the other groups. Single mothers of children with disabilities were found to be more vulnerable to severe depression than mothers living with a partner.
TL;DR: Examination of the relationship between stressors, social support, locus of control, coping styles, and negative outcomes among parents of children with autism indicated that several coping styles corresponded to negative outcomes.
Abstract: Parents of children with autism experience more stress and are more susceptible to negative outcomes than parents of children with other disabilities. The present work examines the relationship between stressors, social support, locus of control, coping styles, and negative outcomes (depression, social isolation, and spousal relationship problems) among parents of children with autism. Fifty-eight parents completed surveys. Results indicated that several coping styles corresponded to negative outcomes. Furthermore, the relationship between stressors and negative outcomes was moderated by social support and coping style. Results are discussed in relation to applications for clinical practice.
TL;DR: It is suggested that amygdala dysfunction in autism might contribute to an impaired ability to link visual perception of socially relevant stimuli with retrieval of social knowledge and with elicitation of social behavior.
Abstract: Autism has been thought to be characterized, in part, by dysfunction in emotional and social cognition, but the pathology of the underlying processes and their neural substrates remain poorly understood. Several studies have hypothesized that abnormal amygdala function may account for some of the impairments seen in autism, specifically, impaired recognition of socially relevant information from faces. We explored this issue in eight high-functioning subjects with autism in four experiments that assessed recognition of emotional and social information, primarily from faces. All tasks used were identical to those previously used in studies of subjects with bilateral amygdala damage, permitting direct comparisons. All subjects with autism made abnormal social judgments regarding the trustworthiness of faces; however, all were able to make normal social judgments from lexical stimuli, and all had a normal ability to perceptually discriminate the stimuli. Overall, these data from subjects with autism show some parallels to those from neurological subjects with focal amygdala damage. We suggest that amygdala dysfunction in autism might contribute to an impaired ability to link visual perception of socially relevant stimuli with retrieval of social knowledge and with elicitation of social behavior.
TL;DR: The prevalence of autism in Brick Township seems to be higher than that in other studies, particularly studies conducted in the United States, but within the range of a few recent studies in smaller populations that used more thorough case-finding methods.
Abstract: Objective. This study determined the prevalence of autism for a defined community, Brick Township, New Jersey, using current diagnostic and epidemiologic methods. Methods. The target population was children who were 3 to 10 years of age in 1998, who were residents of Brick Township at any point during that year, and who had an autism spectrum disorder. Autism spectrum disorder was defined as autistic disorder, pervasive developmental disorder-not otherwise specified (PDD-NOS), and Asperger disorder. The study used 4 sources for active case finding: special education records, records from local clinicians providing diagnosis or treatment for developmental or behavioral disabilities, lists of children from community parent groups, and families who volunteered for participation in the study in response to media attention. The autism diagnosis was verified (or ruled out) for 71% of the children through clinical assessment. The assessment included medical and developmental history, physical and neurologic evaluation, assessment of intellectual and behavioral functioning, and administration of the Autism Diagnostic Observation Schedule—Generic. Results. The prevalence of all autism spectrum disorders combined was 6.7 cases per 1000 children. The prevalence for children whose condition met full diagnostic criteria for autistic disorder was 4.0 cases per 1000 children, and the prevalence for PDD-NOS and Asperger disorder was 2.7 cases per 1000 children. Characteristics of children with autism in this study were similar to those in previous studies of autism. Conclusions. The prevalence of autism in Brick Township seems to be higher than that in other studies, particularly studies conducted in the United States, but within the range of a few recent studies in smaller populations that used more thorough case-finding methods.
TL;DR: A circumscribed network that is active during mentalizing and links medial prefrontal regions with posterior superior temporal sulcus and temporal poles may involve weak connections between components of this system.
TL;DR: Discrete trial training (DTT) is a method for individualizing and simplifying instruction to enhance children's learning as mentioned in this paper, which is especially useful for teaching new forms of instruction for children with autism.
Abstract: Discrete trial training (DTT) is a method for individualizing and simplifying instruction to enhance children's learning. For children with autism, DTT is especially useful for teaching new forms o...
TL;DR: Speakers with AS were significantly more voluble than speakers with HFA, but otherwise there were few statistically significant differences between the two groups of speakers with pervasive developmental disorders.
Abstract: Speech and prosody-voice profiles for 15 male speakers with High-Functioning Autism (HFA) and 15 male speakers with Asperger syndrome (AS) were compared to one another and to profiles for 53 typica...
TL;DR: In this paper, children with a diagnosis of autism and normally developing children, matched for age and general ability, were tested on a series of visual search tasks in two separate experiments.
Abstract: Children with a diagnosis of autism and normally developing children, matched for age and general ability, were tested on a series of visual search tasks in 2 separate experiments. The children with autism performed better than the normally developing children on difficult visual search tasks. This result occurred regardless of whether the target was uniquely defined by a single feature or a conjunction of features, as long as ceiling effects did not mask the difference. Superior visual search performance in autism can be seen as analogous to other reports of enhanced unique item detection in autism. Unique item detection in autism is discussed in the light of mechanisms proposed to be involved in normal visual search performance.
TL;DR: In this article, high-functioning children with autism were compared with two control groups on measures of anxiety and social worries, and high anxiety subscale scores for the autism group were separation anxiety and obsessive-compulsive disorder.
Abstract: High-functioning children with autism were compared with two control groups on measures of anxiety and social worries. Comparison control groups consisted of children with specific language impairment (SLI) and normally developing children. Each group consisted of 15 children between the ages of 8 and 12 years and were matched for age and gender. Children with autism were found to be most anxious on both measures. High anxiety subscale scores for the autism group were separation anxiety and obsessive-compulsive disorder. These findings are discussed within the context of theories of autism and anxiety in the general population of children. Suggestions for future research are made.
TL;DR: Subjects with autism may have specific abnormalities in the AMPA-type glutamate receptors and glutamate transporters in the cerebellum, which may be directly involved in the pathogenesis of the disorder.
Abstract: Background: Studies examining the brains of individuals with autism have identified anatomic and pathologic changes in regions such as the cerebellum and hippocampus. Little, if anything, is known, however, about the molecules that are involved in the pathogenesis of this disorder. Objective: To identify genes with abnormal expression levels in the cerebella of subjects with autism. Method: Brain samples from a total of 10 individuals with autism and 23 matched controls were collected, mainly from the cerebellum. Two cDNA microarray technologies were used to identify genes that were significantly up- or downregulated in autism. The abnormal mRNA or protein levels of several genes identified by microarray analysis were investigated using PCR with reverse transcription and Western blotting. α-Amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid (AMPA)- and NMDA-type glutamate receptor densities were examined with receptor autoradiography in the cerebellum, caudate-putamen, and prefrontal cortex. Results: The mRNA levels of several genes were significantly increased in autism, including excitatory amino acid transporter 1 and glutamate receptor AMPA 1, two members of the glutamate system. Abnormalities in the protein or mRNA levels of several additional molecules in the glutamate system were identified on further analysis, including glutamate receptor binding proteins. AMPA-type glutamate receptor density was decreased in the cerebellum of individuals with autism ( p Conclusions: Subjects with autism may have specific abnormalities in the AMPA-type glutamate receptors and glutamate transporters in the cerebellum. These abnormalities may be directly involved in the pathogenesis of the disorder.
TL;DR: The finding of two FXS subgroups raises a hypothesis of additional genetic influences in the FXS autism group, warranting further genetic studies.
Abstract: This study was designed to explore the behavioral phenotype of autism in a group of young children with fragile X syndrome (FXS). Twenty-four children with FXS, ages 21 to 48 months, were compared with two well-matched groups: 27 children with autism (AD) and 23 children with other developmental delays (DD), on two standardized autism instruments, as well as on measures of development and adaptive behavior. Two FXS subgroups emerged. One subgroup (n = 16) did not meet study criteria for autism. Their profiles on the autism instruments and the developmental instruments were virtually identical to the other DD group. The other FXS subgroup (n = 8, or 33% of the total FXS group) met study criteria for autism. Their profiles on the autism instruments were virtually identical to the group with autism. The finding of two FXS subgroups raises a hypothesis of additional genetic influences in the FXS autism group, warranting further genetic studies.
TL;DR: A new computer program designed to teach people with autistic spectrum disorders to better recognize and predict emotional responses in others is used and results suggest positive effects.
Abstract: This randomized controlled trial looked at the effect of a new computer program designed to teach people with autistic spectrum disorders to better recognize and predict emotional responses in others. Two groups of 11 children (age 12-18) with autism or Asperger syndrome at two special schools participated: one group used the computer program for 10 half-hour sessions over 2 weeks. Within-program data showed a significant reduction in errors made from first to last use. Students were assessed pre- and post-intervention using facial expression photographs, cartoons depicting emotion-laden situations, and non-literal stories. Scores were not related to age or verbal ability. The experimental group made gains relative to the control group on all three measures. Gains correlated significantly with the number of times the computer program was used and results suggest positive effects. Further research could assess whether these gains generalized into real life or improved performance on theory of mind measures.
TL;DR: In autism and in a heterogeneous group of disorders of cognitive function, overexpression of certain neuropeptides and neurotrophins was observed in peripheral blood drawn in the first days of life.
Abstract: There has been little exploration of major biologic regulators of cerebral development in autism. In archived neonatal blood of children with autistic spectrum disorders (n = 69), mental retardation without autism (n = 60), or cerebral palsy (CP, n = 63) and of control children (n = 54), we used recycling immunoaffinity chromatography to measure the neuropeptides substance P (SP), vasoactive intestinal peptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP), calcitonin gene-related peptide (CGRP), and the neurotrophins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), and neurotrophin 4/5 (NT4/5), Neonatal concentrations of VIP, CGRP, BDNF, and NT4/5 were higher (ANOVA, all p values < 0.0001 by Scheffe test for pairwise differences) in children in the autistic spectrum and in those with mental retardation without autism than in control children. In 99% of children with autism and 97% with mental retardation, levels of at least one of these substances exceeded those of all control children. Concentrations were similar in subgroups of the autistic spectrum (core syndrome with or without mental retardation, other autistic spectrum disorders with or without mental retardation) and in the presence or absence of a history of regression. Among children with mental retardation, concentrations did not differ by severity or known cause (n = 11, including 4 with Down syndrome). Concentrations of measured substances were similar in children with CP as compared with control subjects. SP, PACAP, NGF, and NT3 were not different by diagnostic group. No measured analyte distinguished children with autism from children with mental retardation alone. In autism and in a heterogeneous group of disorders of cognitive function, overexpression of certain neuropeptides and neurotrophins was observed in peripheral blood drawn in the first days of life.
TL;DR: These findings represent the first documented link between the restricted range of interests and stereotyped behaviors pathognomonic of autism and particular neuroanatomic sites.
TL;DR: Behavior analysis has already contributed substantially to the treatment of children with autism, and further gains can result from more use of Skinners analysis of language in Verbal Behavior (1957) and in the resulting conceptual and experimental work.
Abstract: Behavior analysis has already contributed substantially to the treatment of children with autism, and further gains can result from more use of Skinner’s analysis of language in Verbal Behavior (1957) and in the resulting conceptual and experimental work. The approach emphasizes a unit of analysis consisting of the relations between behavior, motivative and discriminative variables, and consequences. Skinner identifies seven types of verbal operants—echoic, mand, tact, intraverbal, textual, transcriptive, and copying a text—which function as components of more advanced forms of language. This approach focuses on the development of each verbal operant (rather than on words and their meanings) and on the independent training of speaker and listener repertoires. Five more specific contributions are described that relate to the importance of (a) an effective language assessment, (b) mand training in early intervention, (c) establishing operations, (d) an intraverbal repertoire, and (e) automatic reinforcement.
TL;DR: Regression analyses showed that parents' stress levels were predicted mainly by psychological rather than demographic variables, and adaptive coping strategies, informal social support sources, and beliefs about the efficacy of the intervention were associated with lower reported stress and higher levels of autism symptomatology wereassociated with higher reported stress.
Abstract: There is increasing international interest in intensive home-based behavioral intervention for children with autism. In the present study, 141 UK parents conducting such interventions completed a questionnaire addressing issues of stress, coping, and support. Regression analyses showed that parents' stress levels were predicted mainly by psychological rather than demographic variables. In particular, adaptive coping strategies, informal social support sources, and beliefs about the efficacy of the intervention were associated with lower reported stress and higher levels of autism symptomatology were associated with higher reported stress. There was also evidence that the use of Passive Appraisal coping and beliefs about the efficacy of the interventions moderated the effects of autism symptomatology on parents' pessimism. Implications of these findings for future research and for the support of families engaged in intensive home-based behavioral intervention are discussed.
TL;DR: Recommendations for using visually cued instruction to guide the social language development of young children with autism as they interact with peers without disabilities are supported.
Abstract: This study investigated the effects of written text and pictorial cuing with supplemental video feedback on the social communication of 5 students with autism and social deficits. Two peers without disabilities participated as social partners with each child with autism to form five triads. Treatment was implemented twice per week and consisted of 10 min of systematic instruction using visual stimuli, 10 min of social interaction, and 10 min of self-evaluation using video feedback. Results showed increases in targeted social communication skills when the treatment was implemented. Some generalized treatment effects were observed across untrained social behaviors, and 1 participant generalized improvements within the classroom. In addition, naive judges reported perceived improvements in the quality of reciprocal interactions. These findings support recommendations for using visually cued instruction to guide the social language development of young children with autism as they interact with peers without disabilities.
TL;DR: Evidence is provided that no correlation exists between the prevalence of MMR vaccination and the rapid increase in the risk of autism over time, and the explanation for the marked increase in risk of the diagnosis of autism in the past decade remains uncertain.
Abstract: Objective: To estimate changes in the risk of autism and assess the relation of autism to the mumps, measles, and rubella (MMR) vaccine. Design: Time trend analysis of data from the UK general practice research database (GPRD). Setting: General practices in the United Kingdom. Subjects: Children aged 12 years or younger diagnosed with autism 1988-99, with further analysis of boys aged 2 to 5 years born 1988-93. Main outcome measures: Annual and age specific incidence for first recorded diagnoses of autism (that is, when the diagnosis of autism was first recorded) in the children aged 12 years or younger; annual, birth cohort specific risk of autism diagnosed in the 2 to 5 year old boys; coverage (prevalence) of MMR vaccination in the same birth cohorts. Results: The incidence of newly diagnosed autism increased sevenfold, from 0.3 per 10 000 person years in 1988 to 2.1 per 10 000 person years in 1999. The peak incidence was among 3 and 4 year olds, and 83% (254/305) of cases were boys. In an annual birth cohort analysis of 114 boys born in 1988-93, the risk of autism in 2 to 5 year old boys increased nearly fourfold over time, from 8 (95% confidence interval 4 to 14) per 10 000 for boys born in 1988 to 29 (20 to 43) per 10 000 for boys born in 1993. For the same annual birth cohorts the prevalence of MMR vaccination was over 95%. Conclusions: Because the incidence of autism among 2 to 5 year olds increased markedly among boys born in each year separately from 1988 to 1993 while MMR vaccine coverage was over 95% for successive annual birth cohorts, the data provide evidence that no correlation exists between the prevalence of MMR vaccination and the rapid increase in the risk of autism over time. The explanation for the marked increase in risk of the diagnosis of autism in the past decade remains uncertain.
TL;DR: Five additional patients with FVS and autism are presented and there was evidence of cognitive deficits, manifestations of autism, and typical phenotypic characteristics of FVS.
Abstract: Autism has been described in association with a variety of medical and genetic conditions. We previously reported on a patient whose clinical phenotype was compatible with both fetal valproate syndrome (FVS) and autism. Here we present five additional patients with FVS and autism. In all five of our patients, there was evidence of cognitive deficits, manifestations of autism, and typical phenotypic characteristics of FVS. The association between this known teratogen and autism has both clinical and research implications.