Autistic Sample Research Articles

The relevance of the interpersonal theory of suicide for predicting past-year and lifetime suicidality in autistic adults

BackgroundWhile there are known risk factors for suicidality in autistic adults, these are often unconnected from theoretical frameworks that might explain why risk is elevated and guide clinical interventions. The present study investigated the relevance of constructs from the Interpersonal Theory of Suicide (ITS), including perceived burdensomeness, thwarted belongingness and acquired capability for suicide, and explored mechanisms through which certain risk factors (relationship status, age at diagnosis) might elevate suicide risk.MethodsAutistic adults (n = 314) completed an online study including measures of depression, anxiety and constructs from the ITS. Linear and multinomial regression analysis disentangled contributions of ITS variables from effects of depression and anxiety for past-year suicide ideation, past-year and lifetime suicide attempts. Mediation analyses examined associations between risk factors and these suicide outcomes via mechanisms proposed by the ITS.ResultsPast-year suicide ideation was associated with burdensomeness, mental rehearsal of suicide plans (a facet of acquired capability), and depression. Greater feelings of burdensomeness, and reduced fear of death, marked out participants who had attempted suicide in comparison to those who had experienced suicide ideation in the past year. Relationship status was indirectly associated with past-year suicide ideation via the mediators of depression and burdensomeness, and was associated with past-year attempts via its effect on ideation. Age at diagnosis was unrelated to any variables.LimitationsCross-sectional research is insensitive to causality and temporal dynamics, which is likely why interaction hypotheses from the ITS were unsupported. Normative measures may be invalid in autistic samples. There was no control group. The autistic sample was unrepresentative of the whole population, particularly autistic people with intellectual disabilities, ethnic/racial minorities, and gender minorities.ConclusionsPerceived burdensomeness and acquired capability appear potentially important to suicide in autistic people, and may mediate the effects of some risk factors. Future research should explore the temporal dynamics of suicide trajectories in longitudinal, prospective designs.

Associations between coping strategies and mental health outcomes in autistic adults.

Compared to the general population, mental health difficulties are commonly reported in autistic adults. However, the ways in which coping strategies are associated with mental health and well-being in this population remain unknown. Further, we do not know if, and if so, how these associations might differ to that of non-autistic adults. In this study, we hypothesized that in both our autistic (N=255) and non-autistic (N=165) adult samples, disengagement coping strategies (e.g., denial) would relate to poorer mental health and well-being, while engagement coping strategies (e.g., problem solving) would relate to better mental health and well-being. Regression analyses revealed that higher use of disengagement coping strategies was significantly associated with higher levels of anxiety and depression, and lower levels of well-being in both samples. In contrast, increased use of engagement coping strategies was associated with better well-being, but only in the autistic sample. Our results contribute to the characterization of negative and positive mental health outcomes in autistic adults from a coping perspective, with potential to offer novel information regarding coping strategies to consider when addressing support options for mental health difficulties in the autistic adult population. LAY SUMMARY: Mental health conditions (such as anxiety and depression) and poor well-being are commonly reported in autistic adults. Research suggests that how one copes with stress is associated with one's mental health and well-being. However, we have little information about how coping strategies relate to the mental health of autistic adults, and whether this might be different in non-autistic adults. In this study, we examined the relationship between coping strategies and mental health in a large group of autistic individuals aged 15-80 years. We then compared this with similar aged non-autistic individuals. We found that in both the autistic and non-autistic individuals, using more disengagement coping strategies (such as being in denial, blaming oneself) was related to poorer mental health and well-being. Additionally, using more engagement coping strategies (such as problem solving, acceptance) was related to better mental health and well-being, but only in the autistic individuals. These results can help inform support services, as they highlight the coping strategies that may need to be focused on (i.e., developing engagement coping strategies and reducing disengagement coping strategies) in order to better support the mental health of autistic individuals.

Autism and chronic ill health: an observational study of symptoms and diagnoses of central sensitivity syndromes in autistic adults

BackgroundAutistic adults, particularly women, are more likely to experience chronic ill health than the general population. Central sensitivity syndromes (CSS) are a group of related conditions that are thought to include an underlying sensitisation of the central nervous system; heightened sensory sensitivity is a common feature. Anecdotal evidence suggests autistic adults may be more prone to developing a CSS. This study aimed to investigate the occurrence of CSS diagnoses and symptoms in autistic adults, and to explore whether CSS symptoms were related to autistic traits, mental health, sensory sensitivity, or gender.MethodsThe full sample of participants included 973 autistic adults (410 men, 563 women, mean age = 44.6) registered at the Netherlands Autism Register, who completed questionnaires assessing autistic traits, sensory sensitivity, CSS, physical and mental health symptoms. The reliability and validity of the Central Sensitization Inventory (CSI) in an autistic sample was established using exploratory and confirmatory factor analyses. Chi2 analyses, independent t-tests, hierarchical regression and path analysis were used to analyse relationships between CSS symptoms, autistic traits, measures of mental health and wellbeing, sensory sensitivity, age and gender.Results21% of participants reported one or more CSS diagnosis, and 60% scored at or above the clinical cut-off for a CSS. Autistic women were more likely to report a CSS diagnosis and experienced more CSS symptoms than men. Sensory sensitivity, anxiety, age and gender were significant predictors of CSS symptoms, with sensory sensitivity and anxiety fully mediating the relationship between autistic traits and CSS symptoms.LimitationsAlthough this study included a large sample of autistic adults, we did not have a control group or a CSS only group. We also could not include a non-binary group due to lack of statistical power.ConclusionsCSS diagnoses and symptoms appear to be very common in the autistic population. Increased awareness of an association between autism and central sensitisation should inform clinicians and guide diagnostic practice, particularly for women where CSS are common and autism under recognised.

The Comprehensive Autistic Trait Inventory (CATI): development and validation of a new measure of autistic traits in the general population

BackgroundTraits and characteristics qualitatively similar to those seen in diagnosed autism spectrum disorder can be found to varying degrees in the general population. To measure these traits and facilitate their use in autism research, several questionnaires have been developed that provide broad measures of autistic traits [e.g. Autism-Spectrum Quotient (AQ), Broad Autism Phenotype Questionnaire (BAPQ)]. However, since their development, our understanding of autism has grown considerably, and it is arguable that existing measures do not provide an ideal representation of the trait dimensions currently associated with autism. Our aim was to create a new measure of autistic traits that reflects our current understanding of autism, the Comprehensive Autism Trait Inventory (CATI).MethodsIn Study 1, 107 pilot items were administered to 1166 individuals in the general population and exploratory factor analysis of responses used to create the 42-item CATI comprising six subscales: Social Interactions, Communication, Social Camouflage, Repetitive Behaviours, Cognitive Rigidity, and Sensory Sensitivity. In Study 2, the CATI was administered to 1119 new individuals and confirmatory factor analysis used to verify the factor structure. The AQ and BAPQ were administered to validate the CATI, and additional autistic participants were recruited to compare the predictive ability of the measures. In Study 3, to validate the CATI subscales, the CATI was administered to 202 new individuals along with existing valid measures qualitatively similar to each CATI subscale.ResultsThe CATI showed convergent validity at both the total-scale (r ≥ .79) and subscale level (r ≥ .68). The CATI also showed superior internal reliability for total-scale scores (α = .95) relative to the AQ (α = .90) and BAPQ (α = .94), consistently high reliability for subscales (α > .81), greater predictive ability for classifying autism (Youden’s Index = .62 vs .56–.59), and demonstrated measurement invariance for sex.LimitationsAnalyses of predictive ability for classifying autism depended upon self-reported diagnosis or identification of autism. The autistic sample was not large enough to test measurement invariance of autism diagnosis.ConclusionsThe CATI is a reliable and economical new measure that provides observations across a wide range of trait dimensions associated with autism, potentially precluding the need to administer multiple measures, and to our knowledge, the CATI is also the first broad measure of autistic traits to have dedicated subscales for social camouflage and sensory sensitivity.

A Preliminary Psychometric Analysis of the Difficulties with Emotion Regulation Scale (DERS) Among Autistic Adolescents and Adults: Factor Structure, Reliability, and Validity.

Emotion dysregulation is common among autistic people, yet few measures have received psychometric evaluation in this population. We examined the factor structure, reliability, and validity of a commonly-used measure of emotion dysregulation, the Difficulties with Emotion Regulation Scale (DERS), in a sample of 156 autistic adolescents and adults. Data were drawn from the NIH National Database for Autism Research (NDAR) and an author's existing dataset. Results demonstrated that the factor structure generally conformed to the original 6-factor model, with modifications. Reliability analyses revealed good-to-excellent internal consistencies. Validity analyses indicated that the DERS was positively associated with measures of anxiety, depression, and alexithymia. Our findings provide preliminary evidence for the utility of the DERS in a small autistic sample, with minor modifications.

Effects of oxytocin administration on salivary sex hormone levels in autistic and neurotypical women

BackgroundOxytocin administration, which may be of therapeutic value for individuals with social difficulties, is likely to affect endogenous levels of other socially relevant hormones. However, to date, the effects of oxytocin administration on endogenous hormones have only been examined in neurotypical individuals. The need to consider multi-hormone interactions is particularly warranted in oxytocin trials for autism due to evidence of irregularities in both oxytocin and sex steroid systems.MethodsIn this double-blind cross-over study, saliva samples were collected from 16 autistic and 29 neurotypical women before and after intranasal administration of 24 IU oxytocin or placebo. Oestradiol, testosterone, and oxytocin levels were quantified in saliva samples. Participants also completed the Autism-Spectrum Quotient (AQ) and Empathy Quotient (EQ) questionnaires.ResultsDistinct patterns of change in testosterone and oestradiol levels pre- to-post-administration were observed in autistic relative to neurotypical women (ANCOVA, p < 0.05 main effect of Group), controlling for sample collection time. The mean percent change oestradiol was + 8.8% for the autism group and − 13.0% for the neurotypical group (t = 1.81, p = 0.08), while the mean percent change testosterone was + 1.1% in the autism group and − 12.6% in the neurotypical group (t = 1.26, p = 0.22). In the oxytocin condition, the mean percent change oestradiol was + 12.6% in the autism group and − 6.9% in the neurotypical group (t = 1.78, p = 0.08), while the mean percent change testosterone was + 14.4% in the autism group and − 15.2% in the neurotypical group (t = 3.00, p = 0.006). Robust regression confirmed that group differences in percent change hormone levels were not driven by a small number of influential individuals. Baseline hormone levels did not differ between groups when considered individually. However, baseline testosterone relative to oestradiol (T:E2 ratio) was higher in autistic women (p = 0.023, Cohen’s d = 0.63), and this ratio correlated positively and negatively with AQ and EQ scores, respectively, in the combined sample.LimitationsFurther studies with larger and more diverse autistic sample are warranted to confirm these effects.ConclusionsThis study provides the first evidence that oxytocin influences endogenous testosterone levels in autistic individuals, with autistic women showing increases similar to previous reports of neurotypical men. These findings highlight the need to consider sex steroid hormones as a variable in future oxytocin trials.

Cross-sectional and longitudinal predictors of quality of life in autistic individuals from adolescence to adulthood: The role of mental health and sleep quality.

Research shows that autistic adults are at risk of a range of physical (e.g. sleep difficulties) and mental health (e.g. anxiety) conditions, as well as lower employment and post-secondary education participation; these all can affect one's quality of life. However, we have little information about what affects quality of life for autistic individuals across the lifespan and whether this differs from non-autistic people. We determined what factors (e.g. mental or physical health challenges) affected quality of life in a large group of autistic individuals aged 15-80 years compared with similar age non-autistic individuals. We also examined what factors affected quality of life of the autistic group 2 years later. We found a similar pattern of results for the autistic and non-autistic groups; depression symptoms, psychological well-being, sleep quality and autonomic symptoms (e.g. sweating) were all significant predictors of quality of life. In addition, among the autistic group, baseline quality of life had the most influence on quality of life 2 years later. These results have implications for support services, as they highlight the relationship between mental health (especially depression) and quality of life. Given that sleep challenges (e.g. insomnia) are related to mental health, an intervention addressing both insomnia and mental health may be most useful in helping autistic individuals improve their quality of life.

Brief Report: Psychometric Properties of the Patient Health Questionaire-9 (PHQ-9) in Autistic Adults.

Despite the high prevalence of depression and other mental illnesses in autistic adults, screening instruments such as the Patient Health Questionnaire (PHQ-9) have not been specifically validated in an autistic sample. Using data from two Autism CRC longitudinal studies (n = 581), confirmatory factor analysis supported the two-factor model (somatic and cognitive/affective) in the autistic sample and one-factor model in the community comparison sample. Confirmatory bifactor analysis also supported use of the PHQ-9 total score in autism. Good convergent validity was found with two measures of psychological well-being for PHQ-9 total and subdomain scores. The PHQ-9 is a useful tool for autism research allowing comparison across autistic and non-autistic participants.

Assessment of pragmatic language in verbal and nonverbal autistic children

Theoretical backgroundLanguage abnormalities in autism spectrum disorder show diversity in their interpretation as well as complexity regarding their evaluation processes. The contribution of the speech therapist in multidisciplinary diagnostic process emphasizes the need to assess the parameters of sociopragmatic nature. AimTo investigate the pragmatic language field of verbal and nonverbal autistic children. MethodsThirty-one children, between 3 and 7 years of age, diagnosed with autism spectrum disorder, had their pragmatic abilities assessed by the ABFW test (the language test for young children vocabulary). ResultsThe total number of nonverbal autistic patients were 27 (87%). The communicative acts total in this sample was 2.4 per minute, and the communicative mean most commonly used by this autistic sample was the gestural mean. The communicative space occupied by children within the dyad was 47.7%. There was a statistically significant difference between the use of abilities that are categorized as interpersonal or non-interpersonal functions between verbal and nonverbal autistics. The comparison of each function between verbal and nonverbal patients showed statistically significant differences in the following functions:“Performative”, “Comment”, “Information request”, “Naming” and “Permission request” for the group of verbal patients, and “Exploratory” and “Game” functions for the nonverbal group. Use of “Self-regulatory”, “Exhibition”, and “Social routine request” functions was not encountered in this sample. ConclusionAlthough the verbal and nonverbal autistic children groups displayed discrepant communicative profiles, both groups showed a greater potential for pragmatic language in the setting of a naturalistic evaluation.

Healthcare Experiences of Autistic Adults

Decision to over-sample people with disabilities: The Gateway sample had a low rate of non-autistic people with disabilities. We over-sampled non-autistic people with disabilities in order to better approximate the general population. By doing so, our sample of nonautistic adults had disability rates, overall healthcare status, and rates of unmet healthcare needs that were similar to studies of the general population. The decisions to over-sample people with disabilities and to present the comparison to all non-autistic individuals as the primary analysis were both made in an attempt to be as conservative as possible. As Dr. Woodruff suggests, the differences between autistic and non-autistic participants were magnified in a secondary analysis in which the comparison group did not include any people with disabilities. Advertisement of the Gateway Project: We used multiple different fliers and announcements to recruit participants to the Gateway Project. Those targeted to general populations did not mention autism. It is still possible that some non-autistic participants learned about the study via fliers targeted to the autistic population, but as Dr. Woodruff suggests, inclusion of such individuals is likely to bias results toward the null hypothesis. High proportion of participants with diagnoses of Asperger’s: Due to the growing realization that distinctions between autistic disorder and Asperger’s disorder are unreliable, the American Psychiatric Association has decided to replace these diagnoses with a single diagnosis of Autistic Spectrum Disorder in the Diagnostic and Statistical Manual, fifth edition (DSM-5). We agree that these clinical distinctions are unreliable and may not be a useful way to describe the sample. High proportion of women in the autistic sample: We, too, were surprised at the high proportion of women in the autistic sample. The study was targeted to the online autistic community. Though there is little research describing the online autistic community, our team members, collectively, have spent a large amount of time interacting with this community. It is our informal impression that women are over-represented in the online autistic community. As we mention throughout the article, our findings should not be generalized to autistic adults who do not use the Internet. More research needs to be done to understand the healthcare experiences of the entire autistic population.

Urinary polyomavirus infections in neurodevelopmental disorders

We have recently reported enhanced frequencies of polyomavirus infection in post-mortem brain tissue of autistic patients compared to controls. To further explore potential contributions to neurodevelopmental disorders by polyomaviruses, we have employed specie-specific TaqMan assays to assess the prevalence and titres of BKV, JCV and SV40 inthe urines of 87 patients with autism spectrum disorder, 84 controls matched by sex and age with the autistic sample, 15 subjects with Down syndrome and 13 fragile X individuals. Prevalence rates of urinary BKV infection were significantly greater in Down syndrome and fragile X patients compared to autistic and control individuals (P

Representational drawing and the transition from intellectual to visual realism in children with autism

The present study compared the representational drawings of children with autism, children with Down syndrome and typically developing children. Participants were asked to draw a series of objects and their depictions were scored for the incidence of intellectual realism. The tasks sought evidence of conceptual as opposed to episodic influences on intellectual realism in terms of (1) omission errors for the visible decorative attributes of isolated objects and (2) commission errors for the hidden categorical attributes of contextually situated objects. All groups evinced sensitivity to meaning as gauged by the former measure but the autistic group were impaired in their performance on the latter measure. Whereas children without autism were less likely to depict the occluded handle of a cup when the model was presented in context rather than independently, this trend was lacking in the autistic sample. We consider these findings in terms of weak central coherence and alternative accounts of impaired conceptualization in autism.

Levetiracetam versus placebo in childhood and adolescent autism: a double-blind placebo-controlled study

The purpose of this study was to determine the safety and efficacy of the anticonvulsant levetiracetam in the treatment of children with autism. A previous open-label study in autistic children treated with levetiracetam demonstrated effectiveness in hyperactivity, impulsivity/aggression, and mood lability. Twenty patients with autism ranging from 5 to 17 years of age were entered into a 10-week, placebo-controlled, double-blind trial of levetiracetam versus placebo. The mean maximum dosage for levetiracetam was 862.50+/-279.19 mg/day. We evaluated global improvement of autism with the Clinical Global Impression-Improvement (CGI-I) Scale and aggression and affective instability with the Aberrant Behavior Checklist (ABC) parent and teacher ratings. We measured repetitive behaviors using the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) score and impulsivity and hyperactivity with the Conners' Rating Scale-Revised: Long Version for parent and teacher. No significant difference was found between levetiracetam and placebo groups comparing the change in CGI-I (t=0.350, d.f.=13.621, P=0.765), nor on change in ABC, CY-BOCS or Conners' scales. These findings suggest that levetiracetam does not improve behavioral disturbances of autism, but are limited by the small sample size and lack of stratification of the autistic sample at baseline.

Increased frontal cortical folding in autism: a preliminary MRI study

The gyrification index (GI), the ratio of total to outer cortical contour, was applied to measure the cerebral folding patterns in autism. GI was examined on a frontal coronal slice obtained from MRI scans of 30 nonmentally retarded individuals with autism and 32 matched healthy controls. In the autistic group, left frontal GI was higher in children and adolescents but not in adults. Cortical folding was decreased bilaterally with age in the total autistic sample but not in controls. These preliminary findings suggest that the gyrification patterns in autism may be abnormal, which could be related to the various cortical anomalies observed in this disorder.

High-functioning autism and schizophrenia: A comparison of an early and late onset neurodevelopmental disorder

Autism and schizophrenia are separate neurodevelopmental disorders that share a number of interpersonal and cognitive deficits. The symptoms of autism first appear during early life while schizophrenic symptoms do not typically appear until adolescence at the earliest. Efforts have been made to characterize the pattern of cognitive function in both disorders, and certain resemblances have become apparent such as deficits in abstract reasoning and the more complex aspects of memory and language. The present study provided a comparison of cognitive function between the two disorders. The autistic sample consisted of well-diagnosed individuals with high-functioning autism (IQ≥70). The schizophrenic sample was divided into four subgroups using Ward's method of cluster analysis. Participants received the Wechsler Adult Intelligence Scale-Revised (WAIS-R), the Halstead Category Test, the Trail Making test, and the Wisconsin Card Sorting test (WCST). The profile of the autism sample was compared with the four schizophrenia cluster profiles. The autism group resembled only one of the schizophrenia clusters, with both showing elevations on the WAIS-R Information and Block Design subtests and depressions on Comprehension and Digit Symbol. It was concluded that individuals with high-functioning autism have a cognitive profile that resembles that of an empirically derived subgroup of schizophrenia patients but that does not resemble profiles found in other schizophrenia subgroups. The pattern itself, marked by a relatively depressed score on the Comprehension subtest among the Verbal subtests and a relatively elevated score on Block Design among the Performance subtests, has been characterized in the past as a prototypic profile for high-functioning autism.

High-functioning autism and schizophrenia A comparison of an early and late onset neurodevelopmental disorder

Autism and schizophrenia are separate neurodevelopmental disorders that share a number of interpersonal and cognitive deficits. The symptoms of autism first appear during early life while schizophrenic symptoms do not typically appear until adolescence at the earliest. Efforts have been made to characterize the pattern of cognitive function in both disorders, and certain resemblances have become apparent such as deficits in abstract reasoning and the more complex aspects of memory and language. The present study provided a comparison of cognitive function between the two disorders. The autistic sample consisted of well-diagnosed individuals with high-functioning autism (IQ> or =70). The schizophrenic sample was divided into four subgroups using Ward's method of cluster analysis. Participants received the Wechsler Adult Intelligence Scale-Revised (WAIS-R), the Halstead Category Test, the Trail Making test, and the Wisconsin Card Sorting test (WCST). The profile of the autism sample was compared with the four schizophrenia cluster profiles. The autism group resembled only one of the schizophrenia clusters, with both showing elevations on the WAIS-R Information and Block Design subtests and depressions on Comprehension and Digit Symbol. It was concluded that individuals with high-functioning autism have a cognitive profile that resembles that of an empirically derived subgroup of schizophrenia patients but that does not resemble profiles found in other schizophrenia subgroups. The pattern itself, marked by a relatively depressed score on the Comprehension subtest among the Verbal subtests and a relatively elevated score on Block Design among the Performance subtests, has been characterized in the past as a prototypic profile for high-functioning autism.

Chromosomal fragility in a behavioral disorder.

Numerous studies have shown there is consistent evidence implicating genetic factors in the etiology of autism. In some cases chromosomal abnormalities have been identified. One type of these abnormalities is gaps and breaks nonrandomly located in chromosomes, denominated fragile sites (FS). We cytogenetically analyzed a group of autistic individuals and a normal population, and we examined the FS found in both samples with the aim of (1) comparing their FS expression, (2) ascertaining whether any FS could be associated with our autistic sample, and (3) examining if there are differences between individual and pooled-data analyses. Different statistical methods were used to analyse the FS of pooled and individual data. Our results show that there are statistically significant differences in the spontaneous expression of breakages between patients and controls, with a minimal sex difference. Using the method for pooled data, eight autosomal FS have preferential expression in patients and five patients were found to be positive at FS Xq27.3. With the method per-individual analysis, four FS emerged as specific in our autistic sample. Inferences of FS from pooled data were different from those of individual data. The findings suggest that although analysis of pooled data is necessitated by the problem of sparse data, analysis of single individuals is essential to know the significance of FS in autism.

Oxytocin and autistic disorder: alterations in peptide forms

Background: Oxytocin (OT) is synthesized as a prohormone that is sequentially processed to peptides. These peptides are the bioactive amidated form (OT) and the C-terminal extended peptides, OT-Gly, OT-Gly-Lys and OT-Gly-Lys-Arg, which are designated together as OT-X. As an extension of our previous study finding decreased plasma OT in autism, studies were conducted to determine whether there were changes in OT peptide forms in autistic children.Methods: Twenty eight male subjects (97 ± 20 months; range, 70–139 months), diagnosed with DSM-IV autistic disorder through observation and semi-structured interview, were compared with 31 age-matched nonpsychiatric control subjects (106 ± 22 months; range, 74–140 months). Using OT antisera with different specificity for the peptide forms, we measured plasma OT and OT-X in each group.Results: T tests showed that there was a decrease in plasma OT (t = 4.4, p < .0001), an increase in OT-X (t = 2.3, p < .03) and an increase in the ratio of OT-X/OT (t = 4.5, p < .0001) in the autistic sample, compared with control subjects.Conclusions: The results suggest that children with autistic disorder show alterations in the endocrine OT system. Deficits in OT peptide processing in children with autism may be important in the development of this syndrome.

Further evidence of intact working memory in autism.

Earlier investigations have found mixed evidence of working memory impairment in autism. The present study examined working memory in a high-functioning autistic sample, relative to both a clinical control group diagnosed with Tourette Syndrome and a typically developing control group. No group differences were found across three tasks and five dependent measures of working memory. Performance was significantly correlated with both age and IQ. It is concluded that working memory is not one of the executive functions that is seriously impaired in autism. We also suggest that the format of administration of working memory tasks may be important in determining whether or not performance falls in the impaired range.

Red blood cell fatty acid compositions in a patient with autistic spectrum disorder: a characteristic abnormality in neurodevelopmental disorders?

The fatty acid compositions of red blood cell (RBC) phospholipids from a patient with autistic spectrum disorder (ASD) had reduced percentages of highly unsaturated fatty acids (HUFA) compared to control samples. The percentage of HUFA in the RBC from the autistic patient was dramatically reduced (up to 70%) when the sample was stored for 6 weeks at −20°C. However, only minor HUFA reductions were recorded in control samples stored similarly, or when the autistic sample was stored at −80°C. A similar instability in RBC HUFA compositions upon storage at −20°C has been recorded in schizophrenic patients. In a number of other neurodevelopmental conditions, including attention deficit hyperactivity disorder (ADHD) and dyslexia, reduced concentrations of RBC HUFA have been recorded. The extent and nature of these aberrations require further assessment to determine a possible common biochemical origin of neurodevelopmental disorders in general. To facilitate this, a large scale assessment of RBC fatty acid compositions in patients with ASD, and related disorders, should be performed as a matter of urgency. Supplementing cells in culture with the tryptophan metabolite indole acrylic acid (IAA) affected the levels of cellular HUFA and prostaglandin production. Indole acroyl glycine (IAG), a metabolite of IAA excreted in urine, is found in high concentrations in patients with neurodevelopmental disorders including ASD, ADHD, dyslexia, Asperger's syndrome and obsessive compulsive disorder.