Recent literature has suggested that individuals with autism spectrum disorder (ASD) or autistic traits (ATs) would be more likely to encounter traumatic events in their lifetime and to develop post-traumatic stress disorder (PTSD). However, the nature of this relationship has not yet been fully elucidated. The aims of this study were to evaluate the relationship between AT and PTSD and to investigate which specific autistic dimension was more associated with trauma and stress-related symptoms.

A total of 68 subjects with ASD and 64 healthy controls (HCs) were assessed with the Adult Autism Subthreshold Spectrum (AdAS Spectrum) and the Trauma and Loss Spectrum (TALS) questionnaires. Statistical analyses included Mann–Whitney U test, chi-square test, calculation of Spearman’s coefficients, and logistic regression analysis.

Patients with significant AT reported a 30% rate of PTSD and higher TALS total and domain scores than HCs, among whom no PTSD was found instead. Significant positive correlations were reported between AdAS Spectrum and TALS-SR scores in the whole sample. AdAS Spectrum total scores were statistically predictive of the presence of PTSD. High scores at AdAS Spectrum Inflexibility and adherence to routine and Restrictive interest and rumination domains were identified as positive predictors of a probable PTSD.

Compared to HCs, subjects with significant AT are more likely to present symptoms of PTSD. In particular, AT related to ruminative thinking, narrow interests, and sensorial reactivity would seem to predict the presence of post-traumatic stress symptomatology.

Multiple risk behaviours (MRBs), typically beginning in adolescence, are associated with increased risk of adverse health and social outcomes. The association between autism and MRBs is little understood.

Data were from the Avon Longitudinal Study of Parents and Children, an UK-based longitudinal, birth cohort study. Exposures were diagnosed autism and four autistic traits: social communication difficulties, pragmatic language, repetitive behaviours and reduced sociability. Outcomes were participation in up to 14 risk behaviours, including alcohol consumption, smoking, risky sexual behaviours and physical inactivity. Outcome data were collected at ages approximately 12, 14, 16 and 18.

Up to 4300 participants were included in latent basis growth curve analyses with adjustment for confounders. Social communication difficulties were associated with an above average level of MRBs engagement at ~12 years (mean difference β 0.26; 95% CI 0.13–0.40), and above average rate of engagement from ages ~12–18 (β 0.08; 95% CI 0.02–0.13). Repetitive behaviours were associated with above average levels of engagement in MRBs at ~12 years (β 0.24; 95% CI 0.09–0.38). Contrastingly, reduced sociability was associated with a reduced rate of engagement in MRBs from ages ~12–18 (β −0.06; 95% CI −0.11 to −0.02). In sex-specific analyses, persisting differences in MRB engagement patterns from ages ~12–18 were observed in males with social communication difficulties and females with reduced sociability temperament.

Having elevated levels of some autistic traits appear to have differentiated effects on MRB engagement patterns. These findings could reflect difficulties fitting in and/or coping mechanisms relating to difficulties with fitting in.

Autism and autistic traits are risk factors for suicidal behaviour.

To explore the prevalence of autism (diagnosed and undiagnosed) in those who died by suicide, and identify risk factors for suicide in this group.

Stage 1: 372 coroners’ inquest records, covering the period 1 January 2014 to 31 December 2017 from two regions of England, were analysed for evidence that the person who died had diagnosed autism or undiagnosed possible autism (elevated autistic traits), and identified risk markers. Stage 2: 29 follow-up interviews with the next of kin of those who died gathered further evidence of autism and autistic traits using validated autism screening and diagnostic tools.

Stage 1: evidence of autism (10.8%) was significantly higher in those who died by suicide than the 1.1% prevalence expected in the UK general alive population (odds ratio (OR) = 11.08, 95% CI 3.92–31.31). Stage 2: 5 (17.2%) of the follow-up sample had evidence of autism identified from the coroners’ records in stage 1. We identified evidence of undiagnosed possible autism in an additional 7 (24.1%) individuals, giving a total of 12 (41.4%); significantly higher than expected in the general alive population (1.1%) (OR = 19.76, 95% CI 2.36–165.84). Characteristics of those who died were largely similar regardless of evidence of autism, with groups experiencing a comparably high number of multiple risk markers before they died.

Elevated autistic traits are significantly over-represented in those who die by suicide.

Studies on psychiatric patients have shown that the presence of autistic traits affects the effectiveness of the treatment, decreasing the likelihood of positive clinical outcomes.

The aim of the present study is to investigate which are the areas of overlap between psychiatric symptoms and the traits of the autism spectrum using a bayesian approach.

A sample of 190 adult psychiatric patients, diagnosed with schizophrenia, bipolar disorder, major depression, and personality disorder participated in the study. The RAADS-R questionnaire was used to assess the presence of autistic traits. The severity of psychiatric symptoms was measured with the BPRS and PANSS scales, the perceived well-being and disability using the Whodas and Whoqol scales, the TOL and STROOP for the measurement of executive functions, the attentional matrices for visual-spatial attention, the Raven for general cognitive skills.

No difference emerged between the diagnoses regarding the presence of symptoms of the autism spectrum, which affects 64% of subjects. Logistic regression showed that the severity of symptoms measured as BPRS and PANSS predicted the probability of having autistic traits. Bayesian regression showed that specific autistic traits are indicative of executive functions deficits. Namely, motor impairment severity measured at RAADS is strongly predicted by rule violation with number of correct moves measured at TOL. The other executive functions seemed to be only moderately linked to autistic traits.

These results provide new information about the expression of comorbidity with autism in psychiatric patients.

Autistic people show diverse trajectories of autistic traits over time, a phenomenon labelled ‘chronogeneity’. For example, some show a decrease in symptoms, whilst others experience an intensification of difficulties. Autism spectrum disorder (ASD) is a dimensional condition, representing one end of a trait continuum that extends throughout the population. To date, no studies have investigated chronogeneity across the full range of autistic traits. We investigated the nature and clinical significance of autism trait chronogeneity in a large, general population sample.

Autistic social/communication traits (ASTs) were measured in the Avon Longitudinal Study of Parents and Children using the Social and Communication Disorders Checklist (SCDC) at ages 7, 10, 13 and 16 (N = 9744). We used Growth Mixture Modelling (GMM) to identify groups defined by their AST trajectories. Measures of ASD diagnosis, sex, IQ and mental health (internalising and externalising) were used to investigate external validity of the derived trajectory groups.

The selected GMM model identified four AST trajectory groups: (i) Persistent High (2.3% of sample), (ii) Persistent Low (83.5%), (iii) Increasing (7.3%) and (iv) Decreasing (6.9%) trajectories. The Increasing group, in which females were a slight majority (53.2%), showed dramatic increases in SCDC scores during adolescence, accompanied by escalating internalising and externalising difficulties. Two-thirds (63.6%) of the Decreasing group were male.

Clinicians should note that for some young people autism-trait-like social difficulties first emerge during adolescence accompanied by problems with mood, anxiety, conduct and attention. A converse, majority-male group shows decreasing social difficulties during adolescence.

Previous case–control studies of autistic spectrum disorder (ASD) have identified altered brain structure such as altered frontal and temporal cortex volumes, or decreased fractional anisotropy (FA) within the inferior fronto-occipital fasciculus in patients. It remains unclear whether subclinical autistic-like traits might also be related to variation in these brain structures.

In this study, we analyzed magnetic resonance imaging (MRI) data of 250 psychiatrically healthy subjects phenotyped for subclinical autistic-like traits using the Autism Spectrum Quotient (AQ). For data analysis, we used voxel-based morphometry of T1-MRIs (Computational Anatomy Toolbox) and tract-based spatial statistics for diffusion tensor imaging data.

AQ attention switching subscale correlated negatively with FA values in the bilateral uncinate fasciculus as well as the bilateral inferior fronto-occipital fasciculus. Higher AQ attention switching subscale scores were associated with increased mean diffusivity and radial diffusivity values in the uncinate fasciculus, while axial diffusivity values within this tract show a negative correlation. AQ attention to detail subscale correlated positively with gray matter volume in the right pre- and postcentral gyrus.

We demonstrate that individuals with higher levels of autism-spectrum-like features show decreased white matter integrity in tracts associated with higher-level visual processing and increased cortical volume in areas linked to movement sequencing and working memory. Our results resemble regional brain structure alterations found in individuals with ASD. This offers opportunities to further understand the etiology and pathogenesis of the disorder and shows a subclinical continuum perspective.

There is increasing interest in the clinical and aetiological overlap between autism spectrum disorders and schizophrenia spectrum disorders, reported to co-occur at both diagnostic and trait levels. Individually, sub-clinical autistic and psychotic traits are associated with poor clinical outcomes, including increased depressive symptomatology, self-harming behaviour and suicidality. However, the implications when both traits co-occur remain poorly understood. The study aimed to (1) examine the relationship between autistic and psychotic traits and (2) determine if their co-occurrence increases depressive symptomatology, self-harm and suicidality.

Cross-sectional data from a self-selecting (online and poster advertising) sample of the adult UK population (n = 653) were collected using an online survey. Validated self-report measures were used to assess sub-clinical autistic and psychotic traits, depressive symptomatology, self-harming behaviour and suicidality. Correlation and regression analyses were performed.

A positive correlation between sub-clinical autistic and positive psychotic traits was confirmed (rs = 0.509, p < 0.001). Overall, autistic traits and psychotic traits were, independently, significant predictors of depression, self-harm and suicidality. Intriguingly, however, depression was associated with a negative interaction between the autistic domain attention to detail and psychotic traits.

This study supports previous findings that sub-clinical autistic and psychotic traits are largely independently associated with depression, self-harm and suicidality, and is novel in finding that their combined presence has no additional effect on depression, self-harm or suicidality. These findings highlight the importance of considering both autistic and psychotic traits and their symptom domains in research and when developing population-based depression prevention and intervention strategies.

Autism spectrum traits are increasingly being reported in individuals who identify as transgender, and the presence of such traits have implications for clinical support. To-date little is known about autism traits in individuals who identify as nonbinary.

To empirically contribute to current research by examining autistic traits in a self-identifying transgender and nonbinary gender group.

One hundred and seventy-seven participants responded to a survey consisting of the Autism Spectrum Quotient (AQ), the Empathy Quotient (EQ), the Systematising Quotient (SQ) and the Reading the Mind in the Eyes Task (RME). Comparisons were made between cisgender, transgender and nonbinary groups.

Individuals with autism spectrum disorder (ASD) or meeting the AQ cut-off score for ASD were over-represented in both the transgender and nonbinary groups. The key variables differentiating the transgender and nonbinary groups from the cisgender group were systematising and empathy. Levels of autistic traits and cases of ASD were higher in individuals assigned female at birth than those assigned male at birth.

A proportion of individuals seeking help and advice about gender identity will also present autistic traits and in some cases undiagnosed autism. Lower levels of empathy, diminished theory of mind ability and literalness may impede the delivery of effective support. Clinicians treating transgender and nonbinary individuals, should also consider whether clients, especially those assigned female at birth, have an undiagnosed ASD.

Although the literature documents low executive functions and sleep deficits in individuals with autism spectrum disorder or subclinical autistic traits, no study has simultaneously examined their relationships in the general child population. This study aimed to examine whether autistic traits impacted real-world executive functions through insufficient sleep in a nationally representative sample of children.

This was a national survey of 6832 primary and secondary school students, aged 8–14 years old, with equal sex distribution (3479 boys, 50.8%). Parents reported their child's nocturnal sleep duration and the need for sleep to maintain their daytime function and the Social Responsiveness Scale and the Behavior Rating Inventory of Executive Function (BRIEF) for their children's autistic traits and real-world executive functions, respectively.

We found that autistic traits exerted indirect effects on real-world executive functions through sleep deficits, independent of sex, and age. Moreover, such an indirect effect was observed only from restricted and repetitive behaviors to executive functions through sleep deficits, but not in the other components of autistic traits (i.e. social communication and interaction).

Our novel findings underscore the importance of sleep and autistic traits in executive functions and suggest potential mechanisms that may underlie the observed correlational structure among autistic behaviors, sleep deficits, and low executive function performance.

Harm avoidance (HA) and “not just right experience” (NJRE) have been proposed to be 2 core motivational processes underlying obsessive-compulsive disorder (OCD). The objective of this study was to explore whether NJRE demarcates a neurodevelopmental OCD subgroup distinct from HA related to autistic traits and/or to a broader phenotype of cognitive rigidity and sensory processing difficulties associated with an earlier age of OCD onset.

A correlational design investigated whether NJRE and HA are distinct entities in OCD and explored their relationship to autism spectrum disorder (ASD) traits measured by the Autism Quotient (AQ), sensory processing, set-shifting, and age of OCD onset in an OCD sample (N=25).

NJRE was only moderately (r=.34) correlated to HA and not significant in this study. Consistent with predictions, NJRE was associated with sensory processing difficulties and an earlier age of OCD onset. No significant relationships were found between NJRE and ASD traits as measured by the AQ or set-shifting difficulties.

These preliminary findings suggest a lack of evidence demonstrating NJRE as a manifestation of core autistic traits as measured by the AQ. However, NJRE was associated with sensory abnormalities and an earlier age of OCD onset. The role of NJRE as a developmental, and possibly neurodevelopmental, risk factor for OCD possibly warrants further investigation.

Autistic-like traits (ALTs), that is restrictions in intuitive social interaction, communication and flexibility of interests and behaviors, were studied in two population-based Swedish twin studies, one in children and one in adults: (1) to examine whether the variability in ALTs is a meaningful risk factor for concomitant attention deficit hyperactivity disorder (ADHD), anxiety, conduct problems, depression and substance abuse, and (2) to assess whether common genetic and environmental susceptibilities can help to explain co-existence of ALTs and traits associated with such concomitant problems.

Two nationwide twin cohorts from Sweden (consisting of 11 222 children and 18 349 adults) were assessed by DSM-based symptom algorithms for autism. The twins were divided into six groups based on their degree of ALTs and the risk for concomitant mental health problems was calculated for each group. Genetic and environmental susceptibilities common to ALTs and the other problem types were examined using bivariate twin modeling.

In both cohorts, even the lowest degree of ALTs increased the risk for all other types of mental health problems, and these risk estimates increased monotonically with the number of ALTs. For all conditions, common genetic and environmental factors could be discerned. Overall, the phenotypic correlation between ALTs and the traits examined were less pronounced in adulthood than in childhood and less affected by genetic compared with environmental factors.

Even low-grade ALTs are relevant to clinical psychiatry as they increase the risk for several heterotypical mental health problems. The association is influenced partly by common genetic and environmental susceptibilities. Attention to co-existing ALTs is warranted in research on a wide range of mental disorders.