The relationship between intelligence and global adaptive functioning in young people with or without neurodevelopmental disorders

Previous studies have shown an association between IQ and adaptive global functioning, i.e. how well a person is functioning in different domains of life. However, it is unclear to what extent such an association applies in children with neurodevelopmental disorders (NDDs). The study group consisted of 550 population-screened children assessed with the K-SADS, WISC-IV, and the C-GAS. Approximately half of the sample had been diagnosed with one or several NDDs (ADHD, autism, language disorder and tic disorder). A factorial ANOVA with IQ level and the presence of NDD was conducted, with C-GAS score as the dependent variable. Results revealed a significant interaction effect between IQ-group and NDD-status. In the non-NDD group (49% girls), higher IQ scores were clearly linked with better global adaptive functioning. Among children with NDDs (35% girls), however, higher IQ scores were not clearly associated with better functioning. Thus, the association between IQ and adaptive functioning were found to differ depending on the presence of NDD. These results have implications for the interpretation of IQ test results in neurodevelopmental assessments and point towards the importance of providing support based on an assessment of needs and functioning rather than scores from IQ tests.

The co-occurrence of neurodevelopmental problems in dyslexia

The primary aim of this study was to explore the overlaps between dyslexia and a range of neurodevelopmental disorders and problems (NDPs), specifically symptoms of attention-deficit/hyperactivity disorder, autism spectrum disorder, atypical sensory perception and developmental coordination disorder. Capitalizing on a population-based sample of twins, secondary aims included estimating the heritability of dyslexia and reporting on the measurement characteristics of the scale used to assess dyslexia. A telephone interview regarding symptoms of dyslexia and other NDPs was conducted with parents of 1,688 nine-year-old twins. The prevalence and the heritability of dyslexia were estimated at 8 and 52%, respectively. The boy: girl ratio was 1.5:1. Results revealed that there was more than an eight-fold increase in (diagnostic proxy) NDPs prevalence in the dyslexia group as compared to typical readers. Quantitatively measured symptoms of inattention, oral language problems and atypical sensory perception significantly predicted dyslexia status in a multivariate analysis. By contrast, ASD-related inflexibility was inversely associated with dyslexia in the multivariate model. In sum, dyslexia often overlaps with other NDPs. The current study provides new knowledge supporting the position to move beyond isolated diagnostic categories into behavioural profiles of co-occurring problems when trying to understand the pattern of strengths and needs in individuals with dyslexia.

Biomarker support for ADHD diagnosis based on Event Related Potentials and scores from an attention test

ADHD is a heterogeneous neurodevelopmental disorder associated with dysfunctions in several brain systems. Objective markers of brain dysfunction for clinical assessment are lacking. Many studies applying electroencephalography (EEG) and neuropsychological tests find significant differences between ADHD and controls, but the effect sizes (ES) are often too small for diagnostic purposes. This study aimed to compute a diagnostic index for ADHD by combining behavioral test scores from a cued visual go/no-go task and Event Related Potentials (ERPs). Sixty-one children (age 9-12 years) diagnosed with ADHD and 69 age- and gender-matched typically developing children (TDC) underwent EEG-recording while tested on a go/no-go task. Based on comparisons of ERP group-means and task-performance, variables that differed significantly between the groups with at least moderate ES were converted to a five points percentile scale and multiplied by the ES of the variable. The sum-scores of the variables constituted the diagnostic index. The index discriminated significantly between patients and TDC with a large ES. This index was applied to an independent sample (20 ADHD, 21 TDC), distinguishing the groups with an even larger ES. The diagnostic index described has the potential to support assessment. Further research establishing diagnostic indexes for differential diagnoses is needed.

Birth month and infant gross motor development: Results from the Japan Environment and Children's Study (JECS)

The association between birth month and neurodevelopmental or psychiatric disorders has been investigated in a number of previous studies; however, the results have been inconsistent. This study investigated the association between birth month and child gross motor development at 6 and 12 months of age in a large cohort of infants (n = 72,203) participating in the Japan Environment and Children’s Study (JECS). Gross motor development was assessed using the Ages and Stages Questionnaire (ASQ-3). At 6 months and 12 months, 20.7% and 14.2%, respectively, had ASQ-3 indications of gross motor problems. Birth month was strongly associated with gross motor development at both time points, particularly at 6 months. Summer-born infants had the worst outcomes at both 6 months and 12 months of age. This outcome applied to the ASQ-3 score itself and to the adjusted Relative Risk (aRR), with the highest aRRs (relative to January-born) among August-born (aRR 2.51; 95%CI 2.27–2.78 at 6 months), and June-born (aRR 1.84; 95%CI 1.63–2.09 at 12 months). Boys had better scores than girls both at 6 and 12 months of age. We speculate that seasonal factors—such as maternal vitamin D deficiency and influenza infection—affecting the fetus in early pregnancy might account for the findings.

Bumetanide for autism: Open-label trial in six children

Aim

Bumetanide, a diuretic agent, that reduces intracellular chloride—thereby reinforcing GABAergic inhibition—has been reported to improve core symptoms of autism in children. Given the positive results reported from French trials of bumetanide in children with autism, we decided to evaluate its effects in a small‐scale pilot study, in advance of a larger randomised controlled study (RCT).

Methods

This was an open‐label three‐month trial of bumetanide on six children (five boys), aged 3–14 years with autism. Ratings according to the Parental Satisfaction Survey (PASS) were used after four and twelve weeks to assess symptom change. Blood electrolyte status was monitored.

Results

Improvement in the PASS domain “Communicative and cognitive abilities” was marked or very marked in four children, and two had some improvements. Few negative side effects were reported.

Conclusion

Our small cohort responded well to bumetanide, particularly with regard to “Communicative and cognitive abilities”. Taken with the evidence from larger‐scale RCTs, we suggest that bumetanide should be considered for inclusion in ethically approved treatment/management trials for children with autism, subject to rigorous follow‐up in large‐scale RCTs.

The road to diagnosis and treatment in girls and boys with ADHD - gender differences in the diagnostic process

INTRODUCTION

The number of referrals for diagnostic assessments of Attention Deficit/Hyperactivity Disorder (ADHD) has increased in the last decade. There is a lack of studies examining the diagnostic process and the treatment provided, particularly from a gender perspective.

METHODS

From a consecutive cohort of Child and Adolescent Psychiatric (CAP) outpatients, the medical records of 50 boys and 50 girls (under 18 years of age) with a diagnosis of ADHD were selected by an Excel random numbers generator. Data about referral reason, diagnostic process and treatment were analysed.

RESULTS

Emotional symptoms were more common as a reason for referral to CAP among girls, whereas neurodevelopmental disorders were more common among boys. Compared to the boys, the girls were older at first visit to CAP and at the ADHD diagnosis. The girls had had more visits to the clinic prior to the ADHD diagnostic decision and had more often been prescribed non-ADHD medication both before and after the ADHD diagnosis. The rate of ADHD medication was similar in boys and girls. Girls had more often been admitted to a CAP inpatient care unit prior to the ADHD diagnosis due to acute psychiatric symptoms, and had received more individual psychotherapeutic counselling.

CONCLUSION

The results highlight the need for broader psychiatric investigations including neuropsychiatric symptoms in girls referred for 'emotional problems'.

Internalizing and neurodevelopmental problems in young people: Educational outcomes in a large population-based cohort of twins

Adolescent internalizing problems such as anxiety and depression have been associated with subsequent educational underachievement. However, it has not been investigated if the association is accounted for by neurodevelopmental disorders (NDDs, i.e., attention-deficit/hyperactivity disorder, autism spectrum disorder, developmental coordination disorder, tic disorder, learning disorder). This study is the first to describe the relationship between internalizing problems at age 15 and educational outcomes in later adolescence while controlling for a wide range of NDDs in childhood, and applying a genetically sensitive design. We used the nation-wide population-based Child and Adolescent Twin Study in Sweden, comprising 4997 fifteen-year-old Swedish twins born between 1994 and 1998. Internalizing problems and NDDs were measured with parental report. Educational outcomes were merit rating and upper secondary education eligibility, retrieved from the National School Register. Internalizing problems at age 15 were found to be negatively associated with educational outcomes in later adolescence. Additive genetics accounted for 89% of the covariation between internalizing problems and merit rating, out of which roughly half were unique genetic effects of internalizing problems and the remaining half due to NDDs. In conclusion, internalizing problems form an important risk factor for subsequent educational underachievement, going beyond the risk conferred by childhood NDDs.

Association of etiological factors across the extreme end and continuous variation in disordered eating in female Swedish twins

BACKGROUND

Accumulating evidence suggests that many psychiatric disorders etiologically represent the extreme end of dimensionally distributed features rather than distinct entities. The extent to which this applies to eating disorders (EDs) is unknown.

METHODS

We investigated if there is similar etiology in (a) the continuous distribution of the Eating Disorder Inventory-2 (EDI-2), (b) the extremes of EDI-2 score, and (c) registered ED diagnoses, in 1481 female twin pairs at age 18 years (born 1992-1999). EDI-2 scores were self-reported at age 18. ED diagnoses were identified through the Swedish National Patient Register, parent-reported treatment and/or self-reported purging behavior of a frequency and duration consistent with DSM-IV criteria. We differentiated between anorexia nervosa (AN) and other EDs.

RESULTS

The heritability of the EDI-2 score was 0.65 (95% CI 0.61-0.68). The group heritabilities in DeFries-Fulker extremes analyses were consistent over different percentile-based extreme groups [0.59 (95% CI 0.37-0.81) to 0.65 (95% CI 0.55-0.75)]. Similarly, the heritabilities in liability threshold models were consistent over different levels of severity. In joint categorical-continuous models, the twin-based genetic correlation was 0.52 (95% CI 0.39-0.65) between EDI-2 score and diagnoses of other EDs, and 0.26 (95% CI 0.08-0.42) between EDI-2 score and diagnoses of AN. The non-shared environmental correlations were 0.52 (95% CI 0.32-0.70) and 0.60 (95% CI 0.38-0.79), respectively.

CONCLUSIONS

Our findings suggest that some EDs can partly be conceptualized as the extreme manifestation of continuously distributed ED features. AN, however, might be more distinctly genetically demarcated from ED features in the general population than other EDs.

Attention-deficit/hyperactivity disorder with developmental coordination disorder: 24-year follow-up of a population-based sample

BACKGROUND

Although the body of research concerning neurodevelopmental disorders is vast, there is a scarcity of longitudinal studies beyond late adolescence, and of studies taking co-existing disorders into account. The present study aimed to investigate outcome in adulthood for children with attention-deficit/hyperactivity disorder (ADHD) combined with developmental coordination disorder (DCD) diagnosed at 6.6 years of age.

METHODS

Out of a screening-based population cohort of 589 individuals, 62 (10 female) diagnosed with ADHD+DCD at mean age 6.6 years naïve to stimulant treatment were followed into adulthood through national registries. Results were compared to a screen- and assessment negative population matched group from the same cohort (PM group, n = 51) and a registry-matched (RM group, n = 410) group of the same county and age.

RESULTS

At 30 to 31 years of age, five deaths had occurred; one in the ADHD+DCD group and two each in the comparison groups. In time to event analyses of the composite outcome of any psychiatric disorder, psychotropic prescription, sick pension or criminal sentence, events occurred at a significantly higher rate in the ADHD+DCD group (p = 0.0032, vs PM group p = 0.0115, vs RM group p = 0.0054). The ADHD+DCD group had significantly higher rates of psychiatric diagnoses, prescriptions of psychoactive medications and occurrence of sick pension than both comparison groups. Further, the ADHD+DCD group had significantly lower educational attainment compared to both comparison groups, more years with unemployment, and overall higher welfare recipiency. Rates of pain diagnoses and analgesic prescriptions did not separate the groups.

CONCLUSION

ADHD+DCD entailed a less favorable outcome in adulthood compared to a non-clinical comparison group and a registry-matched population. Neurodevelopmental disorder diagnosed upon school entry is of prognostic utility with respect to function in adulthood, and warrants early identification and management.

Language/cognitive predictors of literacy skills in 12-year-old children on the autism spectrum

AIM

Some school age children with autism spectrum disorder (ASD) struggle with literacy development, yet, the individual differences are major and not well understood. Moreover, literacy attainment is multi-faceted and literacy skills and difficulties manifest in more than one way. The aim of this study was to describe this variability and to identify language/cognitive predictors of different literacy skills.

METHODS

We assessed different literacy skills (word reading accuracy, reading fluency, reading comprehension, and spelling), along with a set of language/cognitive predictor skills (listening comprehension, rapid automatized naming, phonological awareness and nonverbal cognitive ability), in 12-year-old children with ASD without intellectual disability recruited from a longitudinal study in Sweden.

RESULTS

There was great heterogeneity (from floor to ceiling levels) in literacy skills, with a statistically increased prevalence of poor reading comprehension and reading fluency compared with population norms. In regression analyses, it was shown that concurrent language/cognitive predictor skills (e.g. phonological awareness) were differentially associated with literacy subskills. Moreover, a longitudinal analysis showed that preschool language problems were associated with poor word reading accuracy and spelling in middle school.

CONCLUSIONS

The results confirm previous findings as well as provide new knowledge regarding profiles of literacy (difficulties) in children with ASD; interestingly, the identified predictors of literacy skills in ASD resembled those identified as important in general reading (and dyslexia) research, which might indicate that similar kinds of support and training would be beneficial.

Autism and attention-deficit/hyperactivity disorder in children with cerebral palsy: high prevalence rates in a population-based study

AIM

To assess a total population of school-age children with cerebral palsy (CP) for autism and attention-deficit/hyperactivity disorder (ADHD) with a view to determining their prevalence and to relate findings to motor function, intellectual disability, and other associated impairments.

METHOD

Of 264 children, born between 1999 and 2006, from the CP register of western Sweden, 200 children (109 males, 91 females, median age at assessment 14y, range 7-18y) completed comprehensive screening and further neuropsychiatric clinical assessments.

RESULTS

Ninety children (45%) were diagnosed with autism, ADHD, or both, 59 (30%) were diagnosed with autism, and 60 (30%) were diagnosed with ADHD. Intellectual disability was present in 51%. Two-thirds had autism, ADHD, and/or intellectual disability. In regression models, autism was mainly predicted by intellectual disability (odds ratio [OR]=4.1) and ADHD (OR=3.2), and ADHD was predicted by intellectual disability (OR=2.3) and autism (OR=3.0). Autism was more common in children born preterm (OR=2.0). Gross motor function was not associated with autism. ADHD prevalence was low in children with severe motor impairment, possibly due to diagnostic limitations.

INTERPRETATION

Autism and ADHD were common in this population of children with CP and were mainlyindependent of motor severity and CP type. The strongest predictor of autism/ADHD was intellectual disability. Assessment for autism and ADHD is warranted as part of the evaluation in CP.

WHAT THIS PAPER ADDS

Forty-five percent of the children with cerebral palsy also had autism, attention-deficit/hyperactivity disorder (ADHD), or both. Autism and ADHD were predicted mainly by intellectual disability. Established diagnostic instruments worked well for all but the most disabled group of children.

Anorexia nervosa and autism: a prospective twin cohort study

BACKGROUND

Anorexia nervosa (AN) and autism spectrum disorder (ASD) may be phenotypically and etiologically linked. However, due to the absence of prospective studies, it remains unclear whether the elevation of autistic traits in AN is evident in early childhood. Here, we prospectively investigated autistic traits before and after the first diagnosis of AN.

METHODS

In a population-based sample of 5,987 individuals (52.4% female) from the Child and Adolescent Twin Study in Sweden, parents reported autistic traits at ages 9 and 18. AN and ASD diagnoses were retrieved from the Swedish National Patient Register. In addition, AN diagnoses were ascertained by parent-reported treatment for AN. We compared whether individuals with and without AN differed in autistic traits before the first diagnosis of AN (age 9) and after the first diagnosis of AN (age 18).

RESULTS

We did not find evidence for elevated autistic traits in 9-year-old children later diagnosed with AN. At age 18, however, there was a marked elevation in restricted/repetitive behavior and interests, but only in the subgroup of individuals with acute AN. A less pronounced elevation was observed for social communication problems.

CONCLUSIONS

Coping strategies in individuals with ASD and the somewhat different female ASD phenotype may explain why we did not find elevated autistic traits in children who later developed AN. Alternatively, it is possible that elevated autistic traits were not present prior to the onset of AN, thus questioning the previously reported elevated prevalence of ASD in AN. Future studies should use tailored measurements in order to investigate whether autistic traits in individuals with AN are best conceptualized as an epiphenomenon of the acute AN phase or whether these symptoms indeed represent ASD as a clinically verifiable neurodevelopmental disorder.

Mania symptoms in a Swedish longitudinal population study: The roles of childhood trauma and neurodevelopmental disorders

BACKGROUND

Adult psychiatric disorders are associated with both childhood traumatic experiences (CTEs) and neurodevelopmental disorders (NDDs). CTEs and NDDs frequently co-occur in childhood, but their combined risk effect on the emergence of juvenile mania symptoms has not yet been examined.

METHODS

In a population-representative Swedish twin study, CTEs and NDDs were assessed in 3,348 nine-year old twins born between 1998 and 2001, and treated as dichotomous predictors (any CTEs, any NDDs). Follow-up data were gathered at age 15 through parental reports of mania symptoms, yielding a symptom count score.

RESULTS

Both CTEs and NDDs at age 9 contributed uniquely to an increase in mania symptoms at age 15. Children with both risk factors had 1.6 times the rate of mania symptoms as children with CTEs-only (Incidence rate ratio [IRR] 1.63, 95% CI 1.37-1.93), and 1.3 times the rate of mania symptoms as children with NDDs-only (IRR 1.26, 95% CI 1.06-1.50). There was no evidence for an interactive effect of CTEs and NDDs. NDDs showed a trend towards having a larger effect on mania symptoms than CTEs (NDDs-only vs. CTEs-only: IRR 1.29, 95% CI 0.99-1.68).

LIMITATIONS

Although it is a strength of the study that the data on exposures and outcome were collected prospectively, parental recall of CTEs was required and CTEs may be under-reported.

CONCLUSIONS

NDDs are at least as important as CTEs in the development of mania symptoms, and their risk is additive. Those with a history of both CTEs and NDDs should be monitored closely for the development of more severe psychiatric presentations.

Low prevalence of risk drinking in adolescents and young adults with autism spectrum problems

Individuals with Autism Spectrum Disorder (ASD) have high rates of "comorbidity". Research on concurrent substance use (disorder) in ASD, however, is scarce and findings have been inconsistent. This study aims at assessing the prevalence of risk drinking in adolescent and young adult twins with and without autism spectrum problems. Data from a Swedish longitudinal nationwide twin study were analyzed. Across three age groups of 15- (N = 10,050), 18- (N = 7,931) and 24-year-olds (N = 2,882) prevalence rates of risk drinking were compared between twins with and without an ASD proxy diagnosis and between different ASD subgroups based on comorbid proxies for attention-deficit/hyperactivity disorder (ADHD) and/or Learning Disorder (LD). ASD, ADHD, and LD were assessed using the Autism-Tics, ADHD, and other Comorbidities inventory (A-TAC), and risk drinking was captured by the Alcohol Use Disorders Identification Test (AUDIT; age 18 and 24) and another set of self-report questions (age 15). In each age group, the prevalence of risk drinking in ASD was lower than in individuals without ASD, yet increasing continuously with age. Exploratory subgroup ASD analyses showed a trend towards risk drinking being more common among individuals with co-existing ADHD or LD problems than among those without "comorbidity", although sample sizes were too small to draw any certain conclusions. This study indicates low prevalence of risk drinking in adolescents and young adults with autism spectrum problems and highlights the need for further research on alcohol use in individuals with ASD and comorbid disorders.

Dialogical Family Guidance (dfg)-Development and implementation of an intervention for families with a child with neurodevelopmental disorders

Aim

To describe the development and implementation of a Dialogical Family Guidance (DFG) intervention, aimed at families with a child with neurodevelopmental disorders (NDD).

Design

The DFG components are presented and the content of a DFG training course. Professionals' experiences after the DFG training were evaluated.

Methods

Dialogical Family Guidance development phases and implementation process are examined. The Revised Standards for Quality Improvement Reporting Excellence checklist (SQUIRE 2.0) was used to provide a framework for reporting new knowledge.

Results

The DFG training course seemed to increase possibilities of a more independent role as a nurse to deliver the DFG family intervention. The project showed that the use of dialogue can be difficult for some professionals. Analysis of the questionnaire completed after DFG training reported a high level of satisfaction. DFG training offered a new approach to deliver knowledge and understanding to families using dialogue, including tailored psychoeducation and emotional and practical guidance.

Thirty years after anorexia nervosa onset, serum neurofilament light chain protein concentration indicates neuronal injury

Little is known about the long-term consequences of anorexia nervosa (AN) in terms of possible brain neuronal injury. We aimed at investigating whether women with adolescent-onset AN exhibit increased serum levels of neurofilament light chain protein (NfL), a biomarker for neuronal injury, compared with matched controls at 30-year follow-up. Blood samples were collected from 34 women with adolescent-onset AN and 38 matched healthy comparison women (COMP), at a mean age of 44 years (range 38-48 years). NfL was measured in serum using the in-house single molecule array (Simoa) method. The individuals were asked whether they or their parents had been diagnosed with dementia. The Swedish National Patient Register was searched for diagnoses related to dementia. Serum NfL concentrations were significantly higher in the AN group (AN 27.7 pg/ml; COMP 19.0 pg/ml; p = 0.041). When individuals with medical/neurological disorders in the AN and COMP groups were excluded, there was a statistically non-significant trend towards higher concentrations in the AN group (AN 27.4 pg/ml; COMP 18.8 pg/ml; p = 0.060). None of the participants had been diagnosed with dementia. There was no significant correlation between serum NfL and AN duration (r = 0.15). There was a moderate negative correlation between the serum NfL concentration and the current BMI in the AN group (r = 0.44). This is the first time that serum NfL has been assessed in middle-aged women with a history of adolescent-onset AN. The results suggest that there might be increased axonal degeneration as a sequel of AN. Individuals remaining underweight had higher serum NfL concentrations than those with a normal/high BMI. Additional studies are needed to confirm increased serum NfL concentrations in individuals recovered from AN. There is a need for further study of axonal degeneration as a consequence of AN.

Using the five to fifteen-collateral informant questionnaire for retrospective assessment of childhood symptoms in adults with and without autism or ADHD

Due to lack of previous studies, we aimed at evaluating the use of the Five to Fifteen (FTF) questionnaire in adults with neurodevelopmental disorders (NDD) and in controls without NDD. The NDD group consisted of adults with autism spectrum disorder ASD (n = 183) or attention-deficit/hyperactivity disorder (ADHD) (n = 174) without intellectual disability, recruited from a tertiary outpatient clinic. A web survey was used to collect data from general population adult control group without NDD (n = 738). The participants were retrospectively rated by their parents regarding childhood symptoms, using five to fifteen-collateral informant questionnaire (FTF-CIQ). Adults with NDD had higher FTF-CIQ domain and subdomain scores than controls, and displayed similar test profiles as children with corresponding diagnosis in previous studies. Based on the FTF-CIQ domain scores, 84.2% of the study participants (93% of the controls; 64% of the adults with NDD) were correctly classified in a logistic regression analysis. Likewise, Receiver Operating Characteristic (ROC) curve analysis on FTF-CIQ total sum score indicated that a cut-off value of 20.50 correctly classified 90% of the controls and 67% of the clinical cases, whilst a cut-off value of 30.50 correctly classified 84% of the controls and 77% of the clinical cases. The factor analysis revealed three underlying components: learning difficulties, cognitive and executive functions; social skills and emotional/behavioural symptoms; as well as motor and perceptual skills. Whilst not designed as a diagnostic instrument, the FTF-CIQ may be useful for providing information on childhood symptoms and associated difficulties in individuals assessed for NDD as adults.

Autism classified by magnetic resonance imaging: A pilot study of a potential diagnostic tool

OBJECTIVES

Individual anatomical biomarkers have limited power for the classification of autism. The present study introduces a multivariate classification approach using structural magnetic resonance imaging data from individuals with and without autism.

METHODS

The classifier utilizes z-normalization, parameter weighting, and interindividual comparison on brain segmentation data, for estimation of an individual summed total index (TI). The TI indicates whether the gross morphological pattern of each individual's brain is in the direction of cases or controls.

RESULTS

Morphometric analysis found significant differences within subcortical gray matter structures and limbic areas. There was no significant difference in total brain volume. A case-control pilot-study of TIs in normally intelligent individuals with autism (24) and without (21) yielded a maximal accuracy of 78.9% following cross-validation. It showed a high accuracy compared with machine learning methods when tested on the same dataset. The TI correlated well with the autism quotient (R = 0.51) across groups.

CONCLUSION

These results are on par with studies on autism using machine learning. The main contributions are its transparency and simplicity. The possibility of including additional neuroimaging data further increases the potential of the classifier as a diagnostic aid for neuropsychiatric disorders, as well as a research tool for neuroscientific investigations.

Adverse childhood experiences, epigenetics and telomere length variation in childhood and beyond: a systematic review of the literature

A systematic review following PRISMA guidelines was conducted to answer the question: What epigenetic, telomeric and associated biological changes are associated with exposure to adverse childhood experiences (ACEs) in the under 12s? Using PRISMA guidelines, appropriate databases were searched. 190 papers were returned with 38 articles fully reviewed. Articles were each independently quality rated by two authors using the Crowe Critical Appraisal Tool and data were extracted. Of the 38 articles, 23 were rated as very high quality. Most study participants were adults (n = 7769) with n = 727 child participants. Only seven of the very/high-quality studies were prospective and involved children. Methylation was the most studied method of epigenetic modification. There is some evidence supporting epigenetic modification of certain markers in participants exposed to ACEs measured in adulthood. Research is lacking on non-coding aspects of the epigenome and on coding aspects other than DNA methylation. There is some evidence of a more powerful effect on telomere length if physical neglect was involved. Much further work is required to model biological and psychological effects of epigenetic changes during childhood using prospective study designs. The effect of ACEs on the cellular ageing process during childhood is inadequately investigated and relies solely on measure of telomere length. Future research suggestions are proposed.

Etiology of Autism Spectrum Disorders and Autistic Traits Over Time

IMPORTANCE

The frequency with which autism spectrum disorders (ASDs) are diagnosed has shown a marked increase in recent years. One suggestion is that this is partly because of secular changes in the environment, yet to our knowledge this hypothesis lacks evidence.

OBJECTIVE

To assess whether the relative importance of genetic and environmental associations with ASD and autistic traits has changed over a 16-year and 26-year period.

DESIGN, SETTING, AND PARTICIPANTS

A twin design was used to assess whether the heritability of ASD and autistic traits has changed over time. Data from 2 nationwide Swedish twin cohorts was used: the Swedish Twin Registry (STR; participants born between January 1982 and December 2008) and the Child and Adolescent Twin Study in Sweden (CATSS; participants born between January 1992 and December 2008). Autism spectrum disorder diagnoses were identified for twins in the STR, with follow-up to 2013. Questionnaires assigned screening diagnoses of ASD to CATSS participants and assessed autistic traits. Analyses were performed from September 1, 2018, to March 31, 2019.

EXPOSURES

Each sample was divided into several birth cohorts covering 1982 to 1991 (for the STR only), 1992-1995, 1996-1999, 2000-2003, and 2004-2008.

OUTCOMES

We assessed whether the genetric and environment variance underlying autistic traits changed across birth cohorts and examined whether the relative contribution of genetics and environment to liability for autism changed across birth cohorts.

RESULTS

Data were available for 22 678 twin pairs (5922 female same-sex pairs [26.1%], 5563 male same-sex pairs [24.5%], and 11193 opposite-sex pairs [49.4%]) in the STR and 15 280 pairs (4880 female same-sex pairs [31.9%], 5092 male same-sex pairs [33.3%], and 5308 opposite-sex pairs [34.7%]) in CATSS. The heritability of ASD diagnoses in the STR ranged from 0.88 (95% CI, 0.74-0.96) to 0.97 (95% CI, 0.89-0.99). The heritability of screening diagnoses in CATSS varied from 0.75 (95% CI, 0.58-0.87) to 0.93 (95% CI, 0.84-0.98). Autistic traits showed a modest variance increase over time that was associated with increases in genetic and environmental variance, with the total variance increasing from 0.95 (95% CI, 0.92-0.98) to 1.17 (95% CI, 1.13-1.21) over time.

CONCLUSIONS AND RELEVANCE

Weak evidence was found for changes in the genetic and environmental factors underlying ASD and autistic traits over time. Genetic factors played a consistently larger role than environmental factors. Environmental factors are thus unlikely to explain the increase in the prevalence of ASD.

Schoolchildren with unilateral or mild to moderate bilateral sensorineural hearing loss should be screened for neurodevelopmental problems

AIM

The aim was to assess the rate and overlap of language and other neurodevelopmental problems in children aged 9-12 years with unilateral or mild to moderate bilateral sensorineural hearing loss.

METHODS

Caregivers of 24 of the 58 eligible children, born 2004-2007, registered at the regional audiology department in Gothenburg, Sweden, with these types of hearing loss completed the Five-to-Fifteen questionnaire, a comprehensive screening instrument for neurodevelopmental problems. Of these 24 children, 21 were assessed with the Clinical Evaluation of Language Fundamentals-Fourth Edition (CELF-4). Children with scores indicating definite problem on the Five-to-Fifteen questionnaire and their parents were invited to a clinical neuropaediatric assessment.

RESULTS

Of the 24 children, 13 (54%) screened positive for definite neurodevelopmental problems. Clinical assessments confirmed the presence of at least one neurodevelopmental disorder in eight of these 24, corresponding to 33%. Seven (33%) of the 21 children participating in the CELF-4 had scores indicating a language disorder, of whom four children had a neurodevelopmental disorder according to the neuropaediatric assessment.

CONCLUSION

The results support that schoolchildren with unilateral or mild to moderate bilateral sensorineural hearing loss should undergo neurodevelopmental screening to identify possible coexisting neurodevelopmental problems or disorders.

Narrative Skills in Primary School Children with Autism in Relation to Language and Nonverbal Temporal Sequencing

Recent research has suggested that temporal sequencing of narrative events might be a domain-general ability that underlies oral narrative capacities. The current study investigated this issue in a group of children with known pragmatic and narrative difficulties, namely Autism Spectrum Disorder (ASD). We hypothesized (1) that children with ASD (n = 45) would retell narratives of poorer quality than both chronological age-matched (CAM) children and younger children matched on sentence-level language skills (LM), and (2) that nonverbal temporal sequencing skills would uniquely predict individual differences in oral narrative performance in children with ASD. The results show that children with ASD performed poorer on all measures of oral narrative quality compared with the CAM group, and on eight of ten measures compared with the LM group. Thus, our first hypothesis was confirmed, suggesting that narrative difficulties in ASD cannot be fully explained by impaired language. The second hypothesis was only partly confirmed: nonverbal temporal sequencing explained significant or marginally significant variance in some, but not all, aspects of oral narrative performance of children with ASD. These results are discussed from theoretical and clinical/educational perspectives, in relation to the heterogeneity of language skills in ASD and to domain-general features of narrative processing.