Urbanicity and autism spectrum disorders

Observational methods for human studies of transgenerational effects

There are substantial challenges in studying human transgenerational epigenetic outcomes resulting from environmental conditions. The task requires specialized methods and tools that incorporate specific knowledge of multigenerational relationship combinations of probands and their ancestors, phenotype data for individuals, environmental information of ancestors and their descendants, which can span historical to present datasets, and informative environmental data that chronologically aligns with ancestors and descendants over space and time. As a result, there are few epidemiologic studies of potential transgenerational effects in human populations, thus limiting the knowledge of ancestral environmental conditions and the potential impacts we face with modern human health outcomes. In an effort to overcome some of the challenges in studying human transgenerational effects, we present two transgenerational study designs: transgenerational space-time cluster detection and transgenerational case-control study design. Like other epidemiological methods, these methods determine whether there are statistical associations between phenotypic outcomes (e.g., adverse health outcomes) among probands and the shared environments and environmental factors facing their ancestors. When the ancestor is a paternal grandparent, a statistically significant association provides some evidence that a transgenerational inheritable factor may be involved. Such results may generate useful hypotheses that can be explored using epigenomic data to establish conclusive evidence of transgenerational heritable effects. Both methods are proband-centric: They are designed around the phenotype of interest in the proband generation for case selection and family pedigree creation. In the examples provided, we incorporate at least three generations of paternal lineage in both methods to observe a potential transgenerational effect.

Prenatal Exposure to Source-Specific Fine Particulate Matter and Autism Spectrum Disorder

In this study, associations between prenatal exposure to fine particulate matter (PM2.5) from 9 sources and development of autism spectrum disorder (ASD) were assessed in a population-based retrospective pregnancy cohort in southern California. The cohort included 318,750 mother-child singleton pairs. ASD cases (N = 4559) were identified by ICD codes. Source-specific PM2.5 concentrations were estimated from a chemical transport model with a 4 × 4 km2 resolution and assigned to maternal pregnancy residential addresses. Cox proportional hazard models were used to estimate the hazard ratios (HR) of ASD development for each individual source. We also adjusted for total PM2.5 mass and in a separate model for all other sources simultaneously. Increased ASD risk was observed with on-road gasoline (HR [CI]: 1.18 [1.13, 1.24]), off-road gasoline (1.15 [1.12, 1.19]), off-road diesel (1.08 [1.05, 1.10]), food cooking (1.05 [1.02, 1.08]), aircraft (1.04 [1.01, 1.06]), and natural gas combustion (1.09 [1.06, 1.11]), each scaled to standard deviation increases in concentration. On-road gasoline and off-road gasoline were robust for other pollutant groups. PM2.5 emitted from different sources may have different impacts on ASD. The results also identify PM source mixtures for toxicological investigations that may provide evidence for future public health policies.

Positive Autism Screening Rates in Toddlers Born During the COVID-19 Pandemic

Importance

Stress and viral illness during pregnancy are associated with neurodevelopmental conditions in offspring. Autism screening positivity for children born during the pandemic remains unknown.

Objective

To examine associations between prenatal exposure to the pandemic milieu and maternal SARS-CoV-2 infection with rates of positive Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) screenings.

Design, Setting, and Participants

Data for this cohort study were drawn from the COVID-19 Mother Baby Outcomes (COMBO) Initiative. M-CHAT-R scores obtained from children aged 16 to 30 months during routine clinical care at Columbia University Irving Medical Center in New York City were abstracted from electronic health records (EHRs) for children born between January 2018 and September 2021 (COMBO-EHR cohort). Separately, the M-CHAT-R was administered at 18 months for children born between February 2020 and September 2021 through a prospective longitudinal study (COMBO-RSCH cohort). Prenatal pandemic exposure (birth after March 1, 2020) and maternal SARS-CoV-2 status during pregnancy was determined through EHRs. Data were analyzed from March 2022 to June 2024.

Exposures

Prenatal exposures to the pandemic milieu and maternal SARS-CoV-2 infection.

Main Outcomes and Measures

The primary outcome was rate of positive M-CHAT-R screenings. For all primary analyses, unadjusted χ2 tests and adjusted logistic regression models were performed.

Results

The COMBO-EHR cohort included 1664 children (442 born before the pandemic and 1222 born during the pandemic; 997 SARS-CoV-2 unexposed, 130 SARS-CoV-2 exposed, and 95 with unknown SARS-CoV-2 exposure status), of whom 266 (16.0%) were Black, 991 (59.6%) were Hispanic, 400 (24.0%) were White, 1245 (74.8%) were insured through Medicaid, 880 (52.9%) were male, and 204 (12.3%) were born prematurely. The COMBO-RSCH cohort included 385 children (74 born before the pandemic and 311 born during the pandemic; 201 SARS-CoV-2 unexposed, 101 SARS-CoV-2 exposed, and 9 with unknown SARS-CoV-2 exposure status), of whom 39 (10.1%) were Black, 168 (43.6%) were Hispanic, 157 (40.8%) were White, 161 (41.8%) were insured through Medicaid, 222 (57.7%) were male, and 38 (9.9%) were born prematurely. Prenatal pandemic exposure was not associated with a higher positive M-CHAT-R screening rate in either the COMBO-EHR or COMBO-RSCH cohort. Prenatal exposure to maternal SARS-CoV-2 infection was associated with a lower rate of M-CHAT-R positivity in the COMBO-EHR cohort (12.3% [16 children] vs 24.0% [239 children]; adjusted odds ratio, 0.40; 95% CI, 0.22-0.68; P = .001), but no association was found in the COMBO-RSCH cohort (12.9% [13 children] vs 19.9% [40 children]; adjusted odds ratio, 0.51; 95% CI, 0.24-1.04; P = .07).

Conclusions and Relevance

In this cohort study of 2 groups of children with prenatal pandemic exposure and/or exposure to maternal SARS-CoV-2 infection, neither exposure was associated with greater M-CHAT-R positivity.

Mapping associations of polygenic scores with autistic and ADHD traits in a single city region

BACKGROUND

The genetic and environmental aetiology of autistic and Attention Deficit Hyperactivity Disorder (ADHD) traits is known to vary spatially, but does this translate into variation in the association of specific common genetic variants?

METHODS

We mapped associations between polygenic scores for autism and ADHD and their respective traits in the Avon Longitudinal Study of Parents and Children (N = 4,255-6,165) across the area surrounding Bristol, UK, and compared them to maps of environments associated with the prevalence of autism and ADHD.

RESULTS

Our results suggest genetic associations vary spatially, with consistent patterns for autistic traits across polygenic scores constructed at different p-value thresholds. Patterns for ADHD traits were more variable across thresholds. We found that the spatial distributions often correlated with known environmental influences.

CONCLUSIONS

These findings shed light on the factors that contribute to the complex interplay between the environment and genetic influences in autistic and ADHD traits.

Childhood urbanicity is associated with emotional episodic memory-related striatal function and common variation in NTRK2

BACKGROUND

Childhoods in urban or rural environments may differentially affect the risk of neuropsychiatric disorders, possibly through memory processing and neural response to emotional stimuli. Genetic factors may not only influence individuals' choices of residence but also modulate how the living environment affects responses to episodic memory.

METHODS

We investigated the effects of childhood urbanicity on episodic memory in 410 adults (discovery sample) and 72 adults (replication sample) with comparable socioeconomic statuses in Beijing, China, distinguishing between those with rural backgrounds (resided in rural areas before age 12 and relocated to urban areas at or after age 12) and urban backgrounds (resided in cities before age 12). We examined the effect of childhood urbanicity on brain function across encoding and retrieval sessions using an fMRI episodic memory paradigm involving the processing of neutral or aversive pictures. Moreover, genetic association analyses were conducted to understand the potential genetic underpinnings that might contribute to memory processing and neural mechanisms influenced by early-life urban or rural environments.

RESULTS

Episodic memory retrieval accuracy for more difficult neutral stimuli was similar between those with urban and rural childhoods, whereas aversive stimuli elicited higher retrieval accuracy in the urban group (P = 0.023). For aversive stimuli, subjects with urban childhood had relatively decreased engagement of the striatum at encoding and decreased engagement of the hippocampus at retrieval. This more efficient striatal encoding of aversive stimuli in those with urban childhoods was associated with common variation in neurotrophic tyrosine kinase receptor type 2 (NTRK2) (right striatum: P = 1.58×10-6). These findings were confirmed in the replication sample.

CONCLUSIONS

We suggest that this differential striatal processing of aversive stimuli observed in individuals with urban or rural childhoods may represent mechanisms by which childhood urbanicity may affect brain circuits, heightening behavioral responses to negative stressors associated with urban environments. NTRK2-associated neural processes in the striatum may play a role in these processes.

Evaluating screening for autism spectrum disorder using cluster randomization

We evaluated the rate of autism spectrum disorder (ASD) in a group invited to a screening program compared to the rates in two groups who received usual care. The population eligible for screening was all children in Iceland registered for their 30-month well-child visits at primary healthcare centers (PHCs) from March 1, 2016, to October 31, 2017 (N = 7173). The PHCs in the capital area of Reykjavik were the units of cluster randomization. Nine PHCs were selected for intervention (invited group), while eight PHCs received usual care (control group 1). PHCs outside the capital area were without randomization (control group 2). An interdisciplinary team, including a pediatrician contributing with physical and neurological examination, a psychologist evaluating autism symptoms using a diagnostic instrument, and a social worker interviewing the parents, reached a consensus on the clinical diagnosis of ASD according to the ICD-10 diagnostic system. Children in the population were followed up for at least two years and 119 cases were identified. The overall cumulative incidence of ASD was 1.66 (95% confidence interval (CI): 1.37, 1.99). In the invited group the incidence rate was 2.13 (95% CI: 1.60, 2.78); in control group 1, the rate was 1.83 (95% CI: 1.31, 2.50); and in control group 2, the rate was 1.02 (95% CI: 0.66, 1.50). Although the rate of ASD was higher in the invited group than in the control groups, the wide confidence intervals prevented us from concluding definitively that the screening detected ASD more readily than usual care.

Urban and rural differences in needs, service use and satisfaction among caregivers of autistic children in Morocco

LAY ABSTRACT

It is very important to understand the needs of caregivers to be able to empower caregivers and to develop or improve services around the world. Therefore, research in different regions is needed to understand differences in caregivers needs between countries, but also between areas within countries. This study investigated differences in needs and service use between caregivers of autistic children in Morocco, living in urban and rural areas. A total of 131 Moroccan caregivers of autistic children took part in the study and responded to an interview survey. The results showed both similarities and differences between urban and rural living caregivers' challenges and needs. Autistic children from urban communities were much more likely to receive intervention and attend school than children from rural communities, even though age and verbal skills of the two groups of children were comparable. Caregivers expressed similar needs for improved care and education, but different challenges in caring. Limited autonomy skills in children were more challenging to rural caregivers, while limited social-communicational skills were more challenging to urban caregivers. These differences may inform healthcare policy-makers and program developers. Adaptive interventions are important to respond to regional needs, resources, and practices. In addition, the results showed the importance of addressing challenges as experienced by caregivers such as costs related to care, barriers in access to information, or stigma. Addressing these issues may help reduce both global and within-country differences in autism care.

Autism spectrum disorder among 16- to 30-month-old children in Bangladesh: Observational cross-sectional study

LAY ABSTRACT

A nationwide survey was done in Bangladesh to assess autism spectrum disorder prevalence in 16- to 30-month-old children at urban-rural distribution and to determine the association with socioeconomic and demographic conditions. A three-stage cluster sampling method was used where districts from all divisions were selected in the first stage, census enumeration areas as blocks of households were selected in the second stage and households (within the blocks) were selected in the third stage. Thereby, it included 38,440 children from 37,982 households (71% rural, 29% urban) aged 16-30 months from 30 districts of eight divisions of Bangladesh. Screening was done with a 'Red Flag' tool and Modified Checklist for Toddlers and a final diagnosis using Diagnostic and Statistical Manual of Mental Disorders, 5th Edition for autism spectrum disorder. Autism spectrum disorder prevalence was 17 per 10,000 young children - in other words, one in 589 young children. Boys were found at higher risk of autism (one in 423 boys; one in 1026 girls). Prevalence of autism spectrum disorder was higher in urban environments than in rural ones - 25/10,000 and 14/10,000, respectively. More autism spectrum disorder children were found in advanced age groups of parents, especially mothers, and in households with a higher wealth quintile. This survey is significant as it covers both urban and rural areas and specifically targets very young children. The involvement of the Bangladesh Bureau of Statistics, as well as support from the entire healthcare system infrastructure, makes this survey more representative on a national level. Its results will form a database to support the development of an effective early intervention programme in Bangladesh. We hope it will prove useful for researchers, clinicians and frontline healthcare workers, and inform the decisions of policymakers and funders in Bangladesh.

Environmental Influences on Individuals with Autistic Spectrum Disorders with Special Emphasis on Seasonality: An Overview

This paper offers an in-depth exploration of the intricate relationship between environmental factors and autism spectrum disorder (ASD), with a special emphasis on seasonality. It reviews existing research, providing a comprehensive summary of findings and highlighting the multifaceted dimensions of several environmental factors influencing the etiology of ASD. The discussion encompasses various elements, including birth months, maternal health, dietary choices, and vitamin D deficiency, delving into the intricate interplay of seasonality with environmental influences such as viral infections and solar radiation. The present study raises essential questions regarding the timing of environmental influences and the factors contributing to the rising prevalence of ASD. Ultimately, it underscores the need for future epidemiological research to incorporate more extensive investigations of environmental risk factors and employ advanced statistical analyses. This comprehensive overview contributes to a deeper understanding of how environmental factors, particularly seasonality, may be linked to the occurrence of ASD and its increasing prevalence, recognizing the multifaceted and diverse nature of these interactions.

Autism trends in a medium size coastal town of England

Autism spectrum disorder (ASD) is a complex set of neurodevelopmental conditions which affects just under 1% of the global population. This study aims to investigate the trends in ASD diagnoses in a typical English deprived coastal community over the last two decades. ASD information for patients registered at Fleetwood GP practices were provided for the period between July 1952 to March 2022. The incidence and prevalence were calculated and Poisson regression modelling was employed to estimate the effects of age and sex on the number of ASD diagnoses over time. The study shows that there has been an upward trend in the number of ASD diagnoses over the past two decades. Model's results showed that sex differences in ASD diagnoses are less pronounced when accounting for time trends. The study findings show that Fleetwood has experienced a similar rise in ASD cases as the rest of the UK, most likely due to increased awareness that may explain the time effects over gender differences. However, due to the small sample size of the study, confirmation of the gender results and identification of the factors determining the temporal trends are needed in order to determine the gender effects in ASD diagnosis.

Autism incidence and spatial analysis in more than 7 million pupils in English schools: a retrospective, longitudinal, school registry study

BACKGROUND

Understanding how certain factors affect autism incidence can help to identify inequities in diagnostic access. We aimed to investigate the incidence of autism in England as a function of geography and sociodemographics, examining spatial distribution across health service boundaries.

METHODS

In this retrospective, longitudinal, school registry study, we sourced data for the years 2014-17 from the summer school census, which is a component of the National Pupil Database, a government registry of pupils under state education in England. Our main outcome was the incidence of autism in the English state-funded education system, defined by the amount of new autism-specific Education, Health and Care Plans or autism-specific special education needs and disability support recorded during each summer school census year since the 2014 baseline. After excluding prevalent cases in 2014, we calculated unadjusted incidence and age-adjusted, sex-adjusted incidence per 100 000 person-years per subsequent school year and by various sociodemographic categories and local authority districts. We report spatial effects using local indicators of spatial association. We used a three-level mixed-effects logistic regression model with two random intercepts (lower-layer super output area [a geographical area in England containing 1000-3000 residents] and pupil identifier) to calculate odds ratios (ORs) for autism incidence, adjusting for age, sex, ethnicity, claimed eligibility for free school meals, ethnic density quintile, Index of Multiple Deprivation quintile, first language spoken at home, and year, with our reference category being White girls without claimed eligibility for free school meals who speak English as their first language.

FINDINGS

Between 2014 and 2017, our total sample included 31 580 512 person-years and 102 338 newly diagnosed autistic pupils, corresponding to an unadjusted annual autism incidence of 429·1 cases per 100 000 person-years (95% CI 426·4-431·7) and an age-adjusted, sex-adjusted annual incidence of 426·9 cases per 100 000 person-years (423·5-430·4). The adjusted incidence of autism was slightly higher in 2014-15 than in 2015-16 or 2016-17, and, of the age groups, pupils aged 1-3 years, 4-6 years, and 10-12 years had the highest incidence of autism. Adjusted autism incidence in boys was 3·9-times the incidence in girls (668·6 cases per 100 000 person-years [95% CI 662·5-674·6] vs 173·2 cases per 100 000 person-years [170·1-176·3]). Across ethnic groups, adjusted incidence was highest in pupils who had an unclassified ethnicity (599·4 cases per 100 000 person-years [574·5-624·3]) or were Black (466·9 cases per 100 000 person-years [450·8-483·0]). However, in our fully adjusted mixed-effects logistic regression model, we observed lower odds of autism among Asian (OR 0·65 [0·59-0·71]), Black (0·84 [0·77-0·92]), and Chinese (0·62 [0·42-0·92]) girls compared with White girls when these groups had not claimed free school meals and spoke English as a first language. Boys from all ethnicities irrespective of first language spoken and free school meals status had increased odds of autism compared with White girls with no claimed eligibility for free school meals who spoke English as their first language. We also found that claimed free school meal eligibility, first language spoken, sex, and ethnicity differentially impacted the odds of autism. Our spatial analysis showed significant spatial autocorrelation across lower-layer super output areas in England, with 2338 hotspots (high-incidence areas surrounded by other high-incidence areas).

INTERPRETATION

The incidence of autism varies across sex, age, ethnicity, and geographical location. Environmental and social factors might interact with autism aetiology. Speaking a language other than English and economic hardship might increase access barriers to autism diagnostic services, autism-specific Education, Health and Care Plans, and school-level support.

FUNDING

The Commonwealth Fund, the Institute for Data Valorization, the Fonds de recherche du Québec-Santé, Calcul Quebec, the Digital Research Alliance of Canada, the Wellcome Trust, the Innovative Medicines Initiative, the Autism Centre of Excellence, the Simons Foundation Autism Research Initiative, the Templeton World Charitable Fund, the Medical Research Council, the National Institute for Health and Care Research Cambridge Biomedical Research Centre, and the National Institute for Health and Care Research Applied Research Collaboration East of England-Population Evidence and Data Science.

PM2.5 and PM10 air pollution peaks are associated with emergency department visits for psychotic and mood disorders

Particulate matters with a diameter of less than 10 µm (PM10) or less than 2.5 µm (PM2.5) are major air pollutants. Their relationship to psychiatric disorders has not yet been extensively studied. We aimed to explore the relationship between PM10 and PM2.5 air pollution peaks and the daily number of emergency visits for psychotic and mood disorders. Clinical data were collected from the Emergency Department of a Paris suburb (Créteil, France) from 2008 to 2018. Air pollution data were measured by the Paris region air quality network (Airparif) and collected from public databases. Pollution peak periods were defined as days for which the daily mean level of PM was above nationally predefined warning thresholds (20 µg/m3 for PM2.5, and 50 µg/m3 for PM10), and the 6 following days. Multivariable analyses compared the number of daily visits for psychotic and mood (unipolar and bipolar) disorders according to pollution peak, using negative binomial regression. After adjustment on meteorological variables (temperature, humidity, amount of sunshine in minutes), the daily number of emergency visits for psychotic disorders was significantly higher during PM2.5 and PM10 air pollution peak periods; while the number of visits for unipolar depressive disorders was higher only during PM10 peak periods (β = 0.059, p-value = 0.034). There were no significant differences between peak and non-peak periods for bipolar disorders. Differences in the effects of PM air pollution on psychotic and mood disorders should be analyzed in further studies.

Screening for Autism in 2-Year-Old Children: The Application of the Systematic Observation of Red Flags to the Screening Tool for Autism in Toddlers and Young Children

PURPOSE

A multimeasure approach was developed to capitalize on the strengths of two screening measures: the Screening Tool for Autism in Toddlers and Young Children (STAT), an observational measure of social communication, and the Systematic Observation of Red Flags (SORF), a checklist including restricted and repetitive behavior (RRB) items. This approach offers a novel method of identifying autism in toddlers.

METHOD

This was a retrospective study of data collected from a multidisciplinary diagnostic program for 24- to 36-month-olds with developmental delays. Raters with autism expertise but naïve to diagnoses applied the SORF to STAT videos. Psychometrics were derived for the SORF on STAT observations and a multiple-measure approach that used a Least Absolute Shrinkage and Selection Operator modeling framework to construct a STAT-SORF RRB Hybrid, retaining SORF RRB items based on individual predictive abilities.

RESULTS

The SORF alone correctly classified 84% of the sample (84% sensitivity and 86% specificity). The STAT-SORF RRB Hybrid model, which retained four SORF RRB items, correctly classified 90% of a validation sample (95% sensitivity and 75% specificity).

CONCLUSION

These findings highlight the potential utility of using multiple autism identification tools and regression-based scoring to establish presumptive eligibility and facilitate early access to autism interventions.

The complex relationship between greenspace and well-being in children with and without autism

Greenspace (defined here as canopy coverage) positively correlates with improved well-being in typically developing individuals, but this relationship has not been established in children with autism spectrum disorder (ASD). To investigate this relationship, the current study merged data from the National Survey of Children's Health (2012) with the National Land Cover Database. Across typically developing children, children with ASD, and non-autistic children with special healthcare needs (CSHCN), greenspace unexpectedly negatively correlated with well-being. Further, compared with typically developing children, children with ASD or CSHCN status had lower well-being. Interestingly, typically developing children with conduct problems displayed an unexpected negative relationship (i.e. as greenspace increased whereas well-being decreased), though those without conduct problems showed no relationship. Children with ASD displayed no relationship between greenspace independent of conduct problems. CSHCN displayed non-significant trends suggesting mild positive relationships between greenspace and well-being. These data indicate the relationship between greenspace and well-being is more complex than expected and may depend on the diagnostic traits of the population studied.

Evidence of transgenerational effects on autism spectrum disorder using multigenerational space-time cluster detection

Background

Transgenerational epigenetic risks associated with complex health outcomes, such as autism spectrum disorder (ASD), have attracted increasing attention. Transgenerational environmental risk exposures with potential for epigenetic effects can be effectively identified using space-time clustering. Specifically applied to ancestors of individuals with disease outcomes, space-time clustering characterized for vulnerable developmental stages of growth can provide a measure of relative risk for disease outcomes in descendants.

Objectives

(1) Identify space-time clusters of ancestors with a descendent with a clinical ASD diagnosis and matched controls. (2) Identify developmental windows of ancestors with the highest relative risk for ASD in descendants. (3) Identify how the relative risk may vary through the maternal or paternal line.

Methods

Family pedigrees linked to residential locations of ASD cases in Utah have been used to identify space-time clusters of ancestors. Control family pedigrees of none-cases based on age and sex have been matched to cases 2:1. The data have been categorized by maternal or paternal lineage at birth, childhood, and adolescence. A total of 3957 children, both parents, and maternal and paternal grandparents were identified. Bernoulli space-time binomial relative risk (RR) scan statistic was used to identify clusters. Monte Carlo simulation was used for statistical significance testing.

Results

Twenty statistically significant clusters were identified. Thirteen increased RR (> 1.0) space-time clusters were identified from the maternal and paternal lines at a p-value < 0.05. The paternal grandparents carry the greatest RR (2.86–2.96) during birth and childhood in the 1950’s–1960, which represent the smallest size clusters, and occur in urban areas. Additionally, seven statistically significant clusters with RR < 1 were relatively large in area, covering more rural areas of the state.

Conclusion

This study has identified statistically significant space-time clusters during critical developmental windows that are associated with ASD risk in descendants. The geographic space and time clusters family pedigrees with over 3 + generations, which we refer to as a person’s geographic legacy, is a powerful tool for studying transgenerational effects that may be epigenetic in nature. Our novel use of space-time clustering can be applied to any disease where family pedigree data is available.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12942-022-00313-4.

Children with neuro-developmental disorders at Center for Child and Adolescent Mental Health in Cambodia

The Center for Child and Adolescent Mental Health (CCAMH) is one of the centers that have psychiatric specialists for children in Cambodia. This study aims to understand the characteristics of children with neuro-developmental disorders, especially autism spectrum disorder (ASD), at CCAMH. This study included 440 cases that were randomly chosen from 2,147 new patients at CCAMH in 2018-2019 and were aged 0-12 years. Socio-demographic factors, parent's information, obstetrical factors, and clinical data were collected from patients' records. A logistic regression analysis and Pearson's chi-square test were used to compare the characteristics between children who were finally diagnosed with ASD and the others (non-ASD). Of the 440 patients, most were male (75.2%), 0-4 years old (57.7%), and diagnosed with ASD (50.0%). Common symptoms were delay of speech, playing alone, and hyperactivity. ASD was significantly more prevalent in male patients compared to females and in the 0-4 years age group compared to the 5-12 years age group. Parents who lived in Phnom Penh and had high education were more likely to visit the CCAMH with their children who were diagnosed with ASD. Regarding treatment, approximately half of all 440 patients had family counselling and psychosocial education. ASD patients had more speech therapy, special education and structured teaching, and networking and coordination therapy compared to non-ASD patients. To provide education and therapy to children with ASD and their parents from the early stage, information about the center and ASD should be widely distributed to all parents in Cambodia.

Perspectives of Canadian Rural Consultant Pediatricians on Diagnosing Autism Spectrum Disorder: A Qualitative Study

BACKGROUND

Consultant pediatricians represent a potential resource for increasing autism spectrum disorder (ASD) diagnostic capacity; however, little is known about how they perceive their roles in ASD diagnosis.

OBJECTIVE

The objective of this study was to examine the perspectives of rural consultant pediatricians regarding their perceived roles, facilitators, and barriers in ASD diagnosis.

METHODS

We performed a qualitative study using thematic analysis. Consultant pediatricians from 3 small-sized and medium-sized Ontario communities were recruited. Semistructured interviews were conducted, transcribed, coded, and analyzed.

RESULTS

Fourteen pediatricians participated in this study. Participants all considered ASD diagnosis to be in their scope of practice. The major theme identified was the process of diagnosing ASD, which occurred in 3 stages: preassessment (gathering information before the first clinic visit), diagnosis, and service access. All these stages are influenced by ecological factors consisting of characteristics of the child, family, individual physician, pediatric group practice, and the broader system of ASD care.

CONCLUSION

Consultant pediatricians practicing in nonurban Ontario communities see ASD diagnosis as part of their scope of practice and collaboratively work within groups to address the needs of their communities. Strategies aimed at increasing diagnostic capacity should target salaried group practices and improve the efficiency of assessments through preclinic information gathering.

Urban-Rural Disparity in the Incidence of Diagnosed Autism Spectrum Disorder in Taiwan: A 10-Year National Birth Cohort Follow-up Study

Autism spectrum disorder (ASD) is reportedly more prevalent in urban areas partly because of better accessibility and affordability to healthcare. With universal health insurance coverage in Taiwan, a previous study has shown no urban-rural disparity in the utilization rate of a child's preventive healthcare. Under this circumstance, we followed a birth cohort of 176,273 live births from 2006 to 2015 to detect the differences in ASD incidence between urbanicities. After adjusting for socioeconomic factors, children were 1.28 (95% confidence interval (CI): 1.13-1.44) and 1.54 (95% CI: 1.36-1.75) more likely to acquire ASD in satellite and urban areas compared with those in rural areas, respectively. A gradient association between parental educational attainment and ASD incidence was also noted. Greater ASD incidences in more urbanized areas and more advanced educated parents' children were detected under a circumstance with low barriers to healthcare.

The synergistic interaction between urbanicity and maternal education affecting childcare pressure related to autism spectrum disorder in two national birth cohort studies

To gain a holistic approach for parental help-seeking behavior and ASD diagnosis, this study aimed to use two national birth cohort study datasets to investigate the pathway relationship between personal and social/environmental factors, including maternal perceived childcare pressure, maternal level of education, urbanization at age 3, and the chance of receiving a autism spectrum disorder (ASD) diagnosis at when children are aged 5.5 years (2.5 years later). The 2003 Taiwan Birth Cohort Pilot Study (TBCS-p; N = 1618) and 2005 Taiwan Birth Cohort Study (TBCS; N = 19,183) datasets were used. The TBCS-p and TBCS both showed similar prevalence of ASD (0.3-0.4%). Children with ASD characteristics, as measured using the Modified Checklist of Autism in Toddlers, had 8.27-18.20 times increased likelihood of receiving ASD diagnosis [TBCS confidence interval (CF) of 5.32-12.86; TBCS-p CF of 2.03-163.46]. Pathway analysis showed that, although having a mother with higher education or who lived in a city decreased the chance for ASD diagnosis, the interactive effect of a maternal higher level of education and living in a city led to an increased likelihood for ASD diagnosis. Additionally, mothers who perceived a higher level of childcare pressure were also more likely to seek medical assistance and diagnosis. Access to healthcare (living in the city), maternal level of awareness (level of education), and perceived childcare pressure are all factors that influence help-seeking behavior and diagnosis. Therefore, medical professionals should pay special attention to the developmental condition of children in underserved backgrounds and rural areas to prevent delayed diagnosis.

Prevalence and Characteristics of Autism Spectrum Disorder Among Children Aged 8 Years - Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2018

Problem/Condition

Autism spectrum disorder (ASD).

Period Covered

2018.

Description of System

The Autism and Developmental Disabilities Monitoring (ADDM) Network conducts active surveillance of ASD. This report focuses on the prevalence and characteristics of ASD among children aged 8 years in 2018 whose parents or guardians lived in 11 ADDM Network sites in the United States (Arizona, Arkansas, California, Georgia, Maryland, Minnesota, Missouri, New Jersey, Tennessee, Utah, and Wisconsin). To ascertain ASD among children aged 8 years, ADDM Network staff review and abstract developmental evaluations and records from community medical and educational service providers. In 2018, children met the case definition if their records documented 1) an ASD diagnostic statement in an evaluation (diagnosis), 2) a special education classification of ASD (eligibility), or 3) an ASD International Classification of Diseases (ICD) code.

Results

For 2018, across all 11 ADDM sites, ASD prevalence per 1,000 children aged 8 years ranged from 16.5 in Missouri to 38.9 in California. The overall ASD prevalence was 23.0 per 1,000 (one in 44) children aged 8 years, and ASD was 4.2 times as prevalent among boys as among girls. Overall ASD prevalence was similar across racial and ethnic groups, except American Indian/Alaska Native children had higher ASD prevalence than non-Hispanic White (White) children (29.0 versus 21.2 per 1,000 children aged 8 years). At multiple sites, Hispanic children had lower ASD prevalence than White children (Arizona, Arkansas, Georgia, and Utah), and non-Hispanic Black (Black) children (Georgia and Minnesota). The associations between ASD prevalence and neighborhood-level median household income varied by site. Among the 5,058 children who met the ASD case definition, 75.8% had a diagnostic statement of ASD in an evaluation, 18.8% had an ASD special education classification or eligibility and no ASD diagnostic statement, and 5.4% had an ASD ICD code only. ASD prevalence per 1,000 children aged 8 years that was based exclusively on documented ASD diagnostic statements was 17.4 overall (range: 11.2 in Maryland to 29.9 in California). The median age of earliest known ASD diagnosis ranged from 36 months in California to 63 months in Minnesota.

Among the 3,007 children with ASD and data on cognitive ability, 35.2% were classified as having an intelligence quotient (IQ) score ≤70. The percentages of children with ASD with IQ scores ≤70 were 49.8%, 33.1%, and 29.7% among Black, Hispanic, and White children, respectively. Overall, children with ASD and IQ scores ≤70 had earlier median ages of ASD diagnosis than children with ASD and IQ scores >70 (44 versus 53 months).

Interpretation

In 2018, one in 44 children aged 8 years was estimated to have ASD, and prevalence and median age of identification varied widely across sites. Whereas overall ASD prevalence was similar by race and ethnicity, at certain sites Hispanic children were less likely to be identified as having ASD than White or Black children. The higher proportion of Black children compared with White and Hispanic children classified as having intellectual disability was consistent with previous findings.

Public Health Action

The variability in ASD prevalence and community ASD identification practices among children with different racial, ethnic, and geographical characteristics highlights the importance of research into the causes of that variability and strategies to provide equitable access to developmental evaluations and services. These findings also underscore the need for enhanced infrastructure for diagnostic, treatment, and support services to meet the needs of all children.

Associations of parental mental disorders and age with childhood mental disorders: a population-based cohort study with four million offspring

This Taiwan study examined the associations of parental age and mental disorders with the offspring risks of attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), major depressive disorder (MDD), and bipolar disorder (BD). Children born between January 1991 and December 2004 in Taiwan were enrolled as the birth cohort (n = 4,138,151) and followed up until December 2011. A logistic regression analysis was performed to identify the odds ratio (OR). The advanced age effects were significant in ADHD (range of OR: 1.04 to 1.49) and ASD (range of OR: 1.35 to 2.27). Teenage mothers, teenage fathers, and fathers ≥ 50 years had higher offspring risks of MDD (range of OR: 1.24 to 1.46); and teenage mothers and fathers ≥ 50 years had increased offspring risks of BD (range of OR: 1.23 to 1.87). Both paternal and maternal mental disorders were associated with higher risks of within-disorder transmission for ADHD, ASD, MDD, and BD (range of OR: 2.64 to 30.41). Besides, parents with one of these four mental disorders (ADHD, ASD, MDD, and BD) might have higher risk of cross-disorder transmission to at least one of the other three mental disorders in the offspring (range of OR: 1.35 to 7.15). Parental age and mental disorders had complex and nuanced patterns in association with offspring mental disorders.

Mapping the genetic and environmental aetiology of autistic traits in Sweden and the United Kingdom

Background

Autistic traits are influenced by both genetic and environmental factors, and are known to vary geographically in prevalence. But to what extent does their aetiology also vary from place to place?

Methods

We applied a novel spatial approach to data on autistic traits from two large twin studies, the Child and Adolescent Twin Study in Sweden (CATSS; N = 16,677, including 8307 twin pairs) and the Twins Early Development Study in the UK (TEDS; N = 11,594, including 5796 twin pairs), to explore how the influence of nature and nurture on autistic traits varies from place to place.

Results

We present maps of gene‐ and environment‐ by geography interactions in Sweden and the United Kingdom (UK), showing geographical variation in both genetic and environmental influences across the two countries. In Sweden genetic influences appear higher in the far south and in a band running across the centre of the country. Environmental influences appear greatest in the south and north, with reduced environmental influence across the central band. In the UK genetic influences appear greater in the south, particularly in more central southern areas and the southeast, the Midlands and the north of England. Environmental influences appear greatest in the south and east of the UK, with less influence in the north and the west.

Conclusions

We hope this systematic approach to identifying aetiological interactions will inspire research to examine a wider range of previously unknown environmental influences on the aetiology of autistic traits. By doing so, we will gain greater understanding of how these environments draw out or mask genetic predisposition and interact with other environmental influences in the development of autistic traits.

Childhood urbanicity interacts with polygenic risk for depression to affect stress-related medial prefrontal function

Urbanization is increasing globally, and is associated with stress and increased mental health risks, including for depression. However, it remains unclear, especially at the level of brain function, how urbanicity, social threat stressors, and psychiatric risk may be linked. Here, we aim to define the structural and functional MRI neural correlates of social stress, childhood urbanicity, and their putative mechanistic relevance to depressive illness risk, in terms of behavioral traits and genetics. We studied a sample of healthy adults with divergent urban and rural childhoods. We examined childhood urbanicity effects on brain structure as suggested by MRI, and its functional relevance to depression risk, through interactions between urbanicity and trait anxiety-depression, as well as between urbanicity and polygenic risk for depression, during stress-related medial prefrontal cortex (mPFC) engagement. Subjects with divergent rural and urban childhoods were similar in adult socioeconomic status and were genetically homogeneous. Urban childhood was associated with relatively reduced mPFC gray matter volumes as suggested by MRI. MPFC engagement under social status threat correlated with the higher trait anxiety-depression in subjects with urban childhoods, but not in their rural counterparts, implicating an exaggerated physiological response to the threat context with urbanicity, in association with behavioral risk for depression. Stress-associated mPFC engagement also interacted with polygenic risk for depression, significantly predicting a differential mPFC response in individuals with urban but not rural childhoods. Developmental urbanicity, therefore, appears to interact with genetic and behavioral risk for depression on the mPFC neural response to a threat context.

Parental Socioeconomic Status and Autism Spectrum Disorder in Offspring: A Population-Based Cohort Study in Taiwan

Studies from the United States have shown increasing incidence of autism spectrum disorder (ASD) with increasing socioeconomic status (SES), whereas in Scandinavian countries, no such relation was identified. We investigated how ASD risk in offspring varied according to parental SES in Taiwan, where there is universal health care. Through linking birth reporting data and data from Taiwan's national health insurance program, we studied 706,111 singleton births from 2004 to 2007 and followed them until 2015. Parental SES was determined by monthly salary at the time of childbirth, and child neuropsychiatric outcomes were defined using International Classification of Diseases codes. We identified 7,323 ASD cases and 7,438 intellectual disability (ID) cases; 17% of ASD cases had co-occurring ID. In multivariable Cox regression analysis, higher SES was independently associated with higher risk of ASD after we took into account urbanization levels, child sex, parental age, and other covariates. By contrast, higher SES was independently associated with lower risk of ID. Besides the SES disparity in ASD case ascertainment and in the access to health care, findings from Taiwan suggest that other social, environmental, biological, and immunological factors linked with parental SES levels may contribute to the positive relation of SES and ASD risk.

Understanding urbanicity: how interdisciplinary methods help to unravel the effects of the city on mental health

Twenty-first century urbanization poses increasing challenges for mental health. Epidemiological studies have shown that mental health problems often accumulate in urban areas, compared to rural areas, and suggested possible underlying causes associated with the social and physical urban environments. Emerging work indicates complex urban effects that depend on many individual and contextual factors at the neighbourhood and country level and novel experimental work is starting to dissect potential underlying mechanisms. This review summarizes findings from epidemiology and population-based studies, neuroscience, experimental and experience-based research and illustrates how a combined approach can move the field towards an increased understanding of the urbanicity-mental health nexus.

Characterizing Available Tools for Synchronous Virtual Assessment of Toddlers with Suspected Autism Spectrum Disorder: A Brief Report

The COVID-19 pandemic, and associated social distancing mandates, has placed significant limitations on in-person health services, requiring creative solutions for supporting clinicians engaged in the diagnosis of autism spectrum disorder (ASD). This report describes the five virtual instruments available at the time of manuscript development for use by experienced clinicians making diagnostic determinations of ASD for toddlers across the 12- to 36-months age range. We focus on synchronous virtual assessments in which clinicians guide the child's caregiver through a range of assessment activities and observe spontaneous and elicited behaviors. Assessments are compared on dimensions of targeted behavioral domains, specific activities and presses employed, scoring approaches, and other key logistical considerations to guide instrument selection for use in varied clinical and research contexts.

Exploratory spatial analysis of autism rates in New York school districts: role of sociodemographic and language differences

Background

Literature on autism spectrum disorder (ASD) suggests lower ASD prevalence and higher age of diagnosis among children of color, from lower socioeconomic backgrounds, and from families with lower educational levels. These disparities have been attributed to factors such as limited access to diagnostic and treatment services, less opportunity for upward mobility to locales with ample resources, and linguistic barriers. However, few studies describe prevalence and geographic differences of ASD diagnoses by English Language Learner (ELL) status.

Objectives

The primary objectives of this study are to (1) spatially explore the prevalence of ASD among New York State school districts and (2) examine differences of ASD prevalence rates between ELLs and native English-speaking peers.

Methods

Using the 2016–2017 district-level data on public and non-public school age students (3–21 years old) receiving special education services in New York, we analyzed sociodemographic trends among school districts with varying percentages (low, medium, and high ranges) of students with ASD and ELLs. To do this, we conducted exploratory spatial analyses using GIS software, analysis of school district level demographic data, and multivariate linear regression.

Results

In contrast to prior research on ASD prevalence among minority groups, we found disproportionately higher rates of ASD among school districts with higher proportions of Black and Hispanic students. Geographic analysis revealed statistically significant clustering of school districts with high ASD rates in New York City and Albany. Higher proportions of ELLs tended to be concentrated in densely populated, urban, and geographically smaller school districts and had higher proportions of Black, Hispanic, and Asian students.

Conclusions

Schools with higher rates of ASD and ELL students tend to be concentrated in urban regions throughout New York and have higher representation of Black and Hispanic/Latino students, as well as higher rates of learning disabilities in general. Further research is warranted to explore possible reasons for this phenomenon.

The Relationship of Urbanization and Performance of Activity and Participation Functioning among Adults with Developmental Disabilities in Taiwan

Developmental disability is likely to be lifelong in nature and to result in substantial activity and societal participation limitations. The performance of individuals is related to the environment, supports, and urbanization of living cities. Most of the surveys for people with disabilities have not discussed the relationship between the cognitive impairment properties and performance of participation and activities functioning, and most cognitive impairments are regarded as having similar performance. The location of residence in childhood is mainly influenced by parents and main caregivers, but the factors related to the preferences of adults with cognitive impairment in the location of residence are more complicated. Objective(s): The aim was to explore and compare the relationships of the urbanization degree of their living cities and the functioning performance of daily living in various domains among adults with intellectual disability (ID), autism, and concomitant communicative impairment (CCI). Method: The cross-sectional study was applied, and the data was collected face-to-face by professionals in all authorized hospitals in Taiwan. The participants were 5374 adults with ID (n = 4455), autism (n = 670), CCI (n = 110) and combination disabilities (n = 139) which were according to the International Statistical Classification of Diseases 9th Revision (ICD-9) from a total of 167,069 adults with disabilities from the Disability Eligibility System (DES) in Taiwan between July 2012 and October 2013. The authors used the World Health Organization Disability Assessment Schedule 2.0–36 item version of WHO (WHODAS 2.0-36 items) to measure performance and capability of daily living. Results and Conclusions: There were significant differences in age, gender, disabled severity, and the urbanization between all subgroups (p < 0.05). After adjusting the age of all participators, the degree of urbanization just significantly affected the functioning score distribution in domain 1: cognition for an adult with ID, autism, and CCI; in domain 2, mobility for an adult with CCI and combination disability; in domain 3, self-care; domain 4, independent domains for ID (p < 0.05). There were no significant differences between urbanization degree and functioning scores in all domains for adults with autism. All in all, only in groups with combination disability did we find that the worse the degree of impairment was, the lower the degree of urbanization of their place of residence was, and there was no such phenomenon in adults with autism and ID in our study.

The association between newborn screening analytes as measured on a second screen and childhood autism in a Texas Medicaid population

Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. We previously explored whether there was an association of ASD with any analyte measured in the first newborn screening blood test. Here we explore the second screen. Our matched case-control study examined data on 3-5 year-old patients with any ASD diagnosis in the Texas Medicaid system in 2010-2012. Subjects were linked to their 2007-2009 newborn screening blood test data, which included values for 36 analytes or analyte ratios. Data were available for 3,005 cases and 6,212 controls. The most compelling associations were evident for fatty acid oxidation analytes octanoylcarnitine (C8) and octanoylcarnitine/acetylcarnitine (C8/C2). Their adjusted odds ratios comparing 10th versus first analyte deciles were between 1.42 and 1.54 in total births, term births, and males. C8 was consistent with first screen results. Adipylcarnitine (C6DC), an organic acid analyte, showed opposite results in the two screens. Several other analytes exhibiting significant associations in the first screen did not in the second. Our results provide evidence that abnormal newborn blood levels of some carnitines may be associated with risk of later ASD, possibly related to their involvement with mitochondrial function in the developing brain.

Geospatial analysis of births with congenital disorders, Paraná, 2008-2015: ecological study

OBJECTIVE

analyze the pattern of spatial distribution of the prevalence rate of births with congenital disorders and its relationship with social, economic, health care and environmental indicators in Paraná, Brazil, from 2008 to 2015.

METHOD

ecological study with variables extracted from secondary banks, related to the births of children of mothers residing in Paraná, in two quadrennial (2008-2011 and 2012-2015). The analysis of the rates was performed with univariate spatial (Moran) and multivariate approach (Ordinary Least Squares and Geographically Weighted Regression).

RESULTS

the occurrence of congenital disorders presented a significant association (p<0.05) with: registration in primary care of pregnant women over 20 years of age; urbanization degree; consumption of pesticides; and balance of female formal employment.

CONCLUSION/FINAL CONSIDERATIONS

social, health care and environmental variables showed a non-stationary spatial pattern in the analyzed period and influenced positively and negatively the rates.

Urbanicity, biological stress system functioning and mental health in adolescents

Growing up in an urban area has been associated with an increased chance of mental health problems in adults, but less is known about this association in adolescents. We examined whether current urbanicity was associated with mental health problems directly and indirectly via biological stress system functioning. Participants (n = 323) were adolescents from the Dutch general population. Measures included home and laboratory assessments of autonomic nervous system and hypothalamic-pituitary-adrenal axis functioning, neighborhood-level urbanicity and socioeconomic status, and mother- and adolescent self-reported mental health problems. Structural equation models showed that urbanicity was not associated with mental health problems directly. Urbanicity was associated with acute autonomic nervous system and hypothalamic-pituitary-adrenal axis reactivity such that adolescents who lived in more urban areas showed blunted biological stress reactivity. Furthermore, there was some evidence for an indirect effect of urbanicity on mother-reported behavioral problems via acute autonomic nervous system reactivity. Urbanicity was not associated with overall autonomic nervous system and hypothalamic-pituitary-adrenal axis reactivity or basal hypothalamic-pituitary-adrenal axis functioning. Although we observed some evidence for associations between urbanicity, biological stress reactivity and mental health problems, most of the tested associations were not statistically significant. Measures of long-term biological stress system functioning may be more relevant to the study of broader environmental factors such as urbanicity.

Urbanicity and autism of children in China

OBJECTIVES

Increased risk of autism with the increment of urbanization has been documented in developed countries. However, very few studies in developing countries focused on this topic. By using Chinese nationally representative large dataset, we investigated the association between urbanicity and autism among children aged 0-17 years in China. Also, we analyzed whether there existed a sexually dimorphic effect on this association.

METHODS

Data from the Second National Sample Survey on Disability (SNSSD) was used in this study, and 616,940 children was selected for analysis. Autism was measured by experienced psychiatrists according to The International Statistical Classification of Diseases and Related Health Problems 10th Revision Symptom Checklist for Mental Disorders. Logistic regression models allowing for multiple demographic and socioeconomic covariates were used to evaluate the association between the level of urbanization and autism in children.

RESULTS

Compared with children in low level of urbanization areas, those in high urbanization level areas was 2.12 (95%CI: 1.28, 3.49) times more likely to develop autism, and 1.85 (95%CI: 1.21, 2.84) times for those in moderate level of urbanization areas. Stratified analyses found that all observed associations were only in male children, not in female children.

CONCLUSIONS

Our findings suggested that higher level of urbanicity was associated with higher risk of autism in children. This association was only present in male children, not in female children.

Urbanicity, hypothalamic-pituitary-adrenal axis functioning, and behavioral and emotional problems in children: a path analysis

BACKGROUND

Urbanization is steadily increasing worldwide. Previous research indicated a higher incidence of mental health problems in more urban areas, however, very little is known regarding potential mechanisms underlying this association. We examined whether urbanicity was associated with mental health problems in children directly, and indirectly via hypothalamic-pituitary-adrenal (HPA)-axis functioning.

METHODS

Utilizing data from two independent samples of children we examined the effects of current urbanicity (n = 306, ages seven to 12 years) and early childhood urbanicity (n = 141, followed from birth through age 7 years). Children's mothers reported on their mental health problems and their family's socioeconomic status. Salivary cortisol samples were collected during a psychosocial stress procedure to assess HPA axis reactivity to stress, and at home to assess basal HPA axis functioning. Neighborhood-level urbanicity and socioeconomic conditions were extracted from Statistics Netherlands. Path models were estimated using a bootstrapping procedure to detect indirect effects.

RESULTS

We found no evidence for a direct effect of urbanicity on mental health problems, nor were there indirect effects of urbanicity through HPA axis functioning. Furthermore, we did not find evidence for an effect of urbanicity on HPA axis functioning or effects of HPA axis functioning on mental health problems.

CONCLUSIONS

Possibly, the effects of urbanicity on HPA axis functioning and mental health do not manifest until adolescence. An alternative explanation is a buffering effect of high family socioeconomic status as the majority of children were from families with an average or high socioeconomic status. Further studies remain necessary to conclude that urbanicity does not affect children's mental health via HPA axis functioning.

Risk of non-affective psychotic disorder or bipolar disorder in autism spectrum disorder: a longitudinal register-based study in the Netherlands

BACKGROUND

Individuals with autism spectrum disorder (ASD) appear to be at increased risk of non-affective psychotic disorder (NAPD) and bipolar disorder (BD). However, most previous studies examined the co-occurrence of ASD and NAPD or BD, ignoring possible diagnostic bias and selection bias. We used longitudinal data from Dutch psychiatric case registers to assess the risk of NAPD or BD among individuals with ASD, and compared the results to those obtained for the Dutch population in earlier studies.

METHODS

Individuals with ASD (n = 17 234) were followed up between 16 and 35 years of age. Kaplan-Meier estimates were used to calculate the risk of NAPD or BD. We conducted separate analyses to reduce possible bias, including an analysis among individuals diagnosed with ASD before age 16 years (n = 8337).

RESULTS

Of the individuals with ASD, 23.50% (95% confidence interval 21.87-25.22) were diagnosed with NAPD and 3.79% (3.06-4.69) with BD before age 35 years. The corresponding figures for the general population were 0.91% (0.63-1.28) and 0.13% (0.08-0.20). Risk estimates were substantially lower, but still higher than general population estimates, when we restricted our analyses to individuals diagnosed with ASD before age 16, with 1.87% (1.33-2.61) being diagnosed with NAPD and 0.57% (0.21-1.53) with BD before age 25 years. The corresponding figures for the general population were 0.63% (0.44-0.86) and 0.08% (0.05-0.12).

CONCLUSIONS

Individuals with ASD are at increased risk of NAPD or BD. This is likely not the result of diagnostic or selection bias.

Identification and Quantification of Gaps in Access to Autism Resources in the United States: An Infodemiological Study

BACKGROUND

Autism affects 1 in every 59 children in the United States, according to estimates from the Centers for Disease Control and Prevention's Autism and Developmental Disabilities Monitoring Network in 2018. Although similar rates of autism are reported in rural and urban areas, rural families report greater difficulty in accessing resources. An overwhelming number of families experience long waitlists for diagnostic and therapeutic services.

OBJECTIVE

The objective of this study was to accurately identify gaps in access to autism care using GapMap, a mobile platform that connects families with local resources while continuously collecting up-to-date autism resource epidemiological information.

METHODS

After being extracted from various databases, resources were deduplicated, validated, and allocated into 7 categories based on the keywords identified on the resource website. The average distance between the individuals from a simulated autism population and the nearest autism resource in our database was calculated for each US county. Resource load, an approximation of demand over supply for diagnostic resources, was calculated for each US county.

RESULTS

There are approximately 28,000 US resources validated on the GapMap database, each allocated into 1 or more of the 7 categories. States with the greatest distances to autism resources included Alaska, Nevada, Wyoming, Montana, and Arizona. Of the 7 resource categories, diagnostic resources were the most underrepresented, comprising only 8.83% (2472/28,003) of all resources. Alarmingly, 83.86% (2635/3142) of all US counties lacked any diagnostic resources. States with the highest diagnostic resource load included West Virginia, Kentucky, Maine, Mississippi, and New Mexico.

CONCLUSIONS

Results from this study demonstrate the sparsity and uneven distribution of diagnostic resources in the United States, which may contribute to the lengthy waitlists and travel distances-barriers to be overcome to be able to receive diagnosis in specific regions. More data are needed on autism diagnosis demand to better quantify resource needs across the United States.

The association between newborn screening analytes and childhood autism in a Texas Medicaid population, 2010-2012

Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. It is commonly diagnosed at 3 or 4 years of age. We explored whether there was an association of any analytes measured by newborn screening tests with a later diagnosis of ASD. A database was compiled of 3-5 year-old patients with any ASD diagnosis in the Texas Medicaid system in 2010-2012. Two controls (without any ASD diagnosis) were matched to each case by infant sex and birth year/month. All study subjects were linked to their 2007-2009 birth and newborn screening laboratory records, including values for 36 analytes or analyte ratios. We examined the association of analytes/ratios with a later diagnosis of ASD. Among 3,258 cases and 6,838 controls, seven analytes (e.g., 17-hydroxyprogesterone, acylcarnitines) were associated with a later ASD diagnosis. In this exploratory study, an ASD diagnosis was associated with 7 of 36 newborn screening analytes/ratios. These findings should be replicated in other population-based datasets.

Prevalence of DSM-5 Autism Spectrum Disorder Among School-Based Children Aged 3-12 Years in Shanghai, China

We estimated the prevalence of ASD in a population-based sample comprising children aged 3-12 years (N = 74,252) in Shanghai. This included a high-risk group sampled from special education schools and a low-risk group randomly sampled from general schools. First, we asked parents and then teachers to complete the Social Communication Questionnaire for participating children. Children who screened positive based on both parental and teachers' reports were comprehensively assessed. ASD was identified based on DSM-5 criteria. We identified 711 children as being at-risk for ASD, of which 203 were identified as ASD cases. The prevalence of ASD was 8.3 per 10,000, which is likely an underestimate, given that 81.6% of the children diagnosed with ASD had IQs below 40. This is the first report on the prevalence of ASD according to DSM-5 in China.

Prevalence of autism spectrum disorders and their relation to selected socio-demographic factors among children aged 18-30 months in northern Vietnam, 2017

Background

Autism spectrum disorders are increasing worldwide and in Vietnam. This study reports the prevalence of autism spectrum disorders and examines their relation to selected socio-demographic factors among children aged 18 and 30 months in three northern cities/provinces in Vietnam, 2017.

Methods

This was a cross-sectional study conducted among 17,277 children aged 18 and 30 months one city (Hanoi capital) and two provinces in northern Vietnam. The multi-stage sampling technique was applied in this study. We used M-CHAT to screen children with high risk of ASD. M-CHAT positive cases were diagnosed by pediatric neurologists from National Pediatrics Hospital using DSM-IV criteria. Descriptive and analytical statistics were performed.

Results

The overall prevalence of ASD among children aged 18 and 30 months in the three studied sites was 0.752% (95% CI 0.629–0.893%). The odds of having ASD were statistically significant higher among (a) children living in urban area as compared to those from rural settings (OR = 2.7, 95% CI 1.73–4.21); (b) boys as compared to girls (OR = 4.04, 95% CI 2.57–6.35); and (c) children of mothers who worked as farmers as compared to children of mothers who were government staff (OR = 4.72, 95% CI 2.03–10.97).

Conclusions

Our study revealed that the prevalence of ASD among children in Vietnam seems to be increasing. The significant correlates of ASD among the children were urban setting, male gender and mother’s occupation (farmer). Further and more in-depth studies on determinants of ASD are needed to provide insights into the problem.

Attention-Deficit/Hyperactivity Disorder in Childhood and Adolescence and the Risk of Crime in Young Adulthood in a Danish Nationwide Study

OBJECTIVE

To determine the risk of long-term conviction and incarceration associated with childhood attention-deficit/hyperactivity disorder (ADHD), and to identify risk and protective factors including associations with active treatment with ADHD medication.

METHOD

All participants with ADHD who were 4 to 15 years of age during 1995 to 2005 were matched by year of birth and sex to a random sample of participants without ADHD from the Danish population using nationwide registers. Using Cox proportional hazard models, we estimated the risk of conviction and incarceration associated with ADHD in childhood and estimated associations with active treatment and outcome.

RESULTS

The ADHD cohort were followed up at a mean of 22.0 (SD = 5.8) years. Of 4,231 individuals with ADHD, 1,355 (32.0%) had received at least one conviction, compared to 3,059 (15.6%) of the 19,595 participants without ADHD (p < 0.001). ADHD was significantly associated with conviction (hazard ratio [HR] = 2.4, 95% CI = 2.3-2.6) and incarceration (HR = 3.0, 95% CI = 2.8-3.3). Subsequent to adjustment for various risk factors, ADHD exposure was still significantly related to conviction (HR = 1.6, 95% CI = 1.5-1.8) and incarceration (HR = 1.7, 95% CI = 1.5-1.9). Comorbidity with substance use disorder, oppositional-defiant disorder/conduct disorder, low family socioeconomic status, parental incarceration, and parental relationship status all significantly increased the risk of conviction and incarceration. Crime rates increased with the number of associated risks but were reduced during periods of taking ADHD medication.

CONCLUSION

In addition to ADHD, a broad range of individual, familial, and social factors increase the risk of antisocial development. The findings imply that ADHD medication may contribute to crime prevention.

Annual trends in prevalence and incidence of autism spectrum disorders in Manitoba preschoolers and toddlers: 2004-2015

OBJECTIVES

Autism spectrum disorders (ASD) are among the leading causes of disabilities in children. We examined the annual prevalence and incidence rate of ASD between 2004 and 2015 in children aged 1 to 5 years residing in Manitoba.

METHODS

A population-based study was conducted using the Manitoba Population Research Data Repository. The study included children aged 1 to 5 years residing in Manitoba between 2004 and 2015. Standard identification algorithm was used to identify ASD cases from hospital abstracts and medical claims. Annual prevalence and incidence rates were calculated for the overall population and then stratified according to sex, region, and socio-economic status (SES). Multivariable negative binomial regression models, adjusted for sex, region, and SES, were used to examine changes in prevalence and incidence over study years.

RESULTS

Among children aged 1 to 5 years, 1685 ASD cases were diagnosed between 2004 and 2015. The crude ASD prevalence increased from 0.46% in 2004 to 0.97% in 2015 (p = 0.002). The crude incidence rate increased from 0.16% in 2004 to 0.39% in 2015 (p = 0.002). The increase in ASD prevalence and incidence was observed in all subgroups based on sex, region, and SES. The adjusted negative binomial model showed an annual relative risk increase, since 2004, for both prevalence and incidence of 1.69 (95% CI 1.56-1.83) and 1.84 (95% CI 1.62-2.09), respectively.

CONCLUSION

During the period from 2004 to 2015, both prevalence and incidence rates of diagnosed ASD in preschoolers and toddlers residing in Manitoba increased significantly.

Autism spectrum disorders: let's talk about glucose?

Autism spectrum disorders (ASD) are characterized by disconnectivity due to disordered neuronal migration, and by neuronal mitochondrial dysfunction. Different pathways involved in neuronal migration are affected by intrauterine hyperglycemia and hyperinsulinemia, while prolonged neonatal hypoglycemia may cause mitochondrial dysfunction. Our hypothesis was that conditions leading to intrauterine hyperglycemia or neonatal hypoglycemia would influence ASD pathogenesis. In this study, we identified risk factors for ASD by searching PubMed with the MeSH terms "autism spectrum disorder" and "risk factors". We then analyzed the relationship between the risk factors and glucose abnormalities in the mother and the offspring. The relationship between glucose abnormalities and risk factors such as obesity, excessive maternal weight gain, or diabetes mellitus is evident. For risk factors such as malformations or exposure to selective serotonin reuptake inhibitors, the relationship is speculative. In rodents, for example, intrauterine hyperglycemia is associated with malformations, independent of maternal diabetes. In their turn, selective serotonin reuptake inhibitors reduce the signs of neonatal hypoglycemia. Going undetected, prolonged hypoglycemia may harm the neonatal brain. Importantly, our group demonstrated that either high-carbohydrate diets or physical inactivity the day before delivery may influence neonatal glycemia. In that study, of 158 neonates selected to be screened according to maternal lifestyle risk factors, 48 had hypoglycemia. Of note, five of them had not been identified with current screening programs. Controlled studies are needed to clarify whether maternal interventions aiming at maintaining glycemic control, together with screening programs for neonatal hypoglycemia based on maternal lifestyle risk factors and on exposure to specific prenatal medications can reduce the prevalence of ASD.

Geographic Disparities in Treatment for Children with Autism Spectrum Disorder

OBJECTIVE

Geographic differences may provide insight into what factors influence the likelihood that a child is diagnosed with autism spectrum disorder (ASD) in the United States; yet, there have been few nationally representative surveys that have explored this topic. The current study expands the limited literature by analyzing regional differences in ASD prevalence, service utilization, and the presence of unmet needs within a nationally representative sample of children.

METHODS

Data were drawn from the 2014-2016 National Health Interview Survey (NHIS), a nationally representative household survey of the noninstitutionalized US population. Children 3 to 17 years of age were included in the analytic sample. Prevalence estimates accounted for the complex survey design of the NHIS, and differences between geographic regions were compared using logistic/linear regressions with and without adjustment for child/family characteristics.

RESULTS

The prevalence of ASD was highest in the Northeast (3.0%), followed by the Midwest (2.4%), South (2.4%), and West (2.3%). A significant difference was found between the Northeast and West (P < .05); however, after accounting for child and family characteristics, this difference was no longer significant. Children with ASD in the Northeast were the most likely to have seen a specialist in the past year. Approximately 1 in 8 children with ASD experienced at least 1 unmet need, but there were no differences found by geographic region.

CONCLUSIONS

Although differences in prevalence were not significant after adjustment, service utilization differences remained. It appears that children with ASD in the Northeast utilize the greatest number of specialty services when compared to children with ASD from other parts of the country.

Prenatal exposure to TiO2 nanoparticles in mice causes behavioral deficits with relevance to autism spectrum disorder and beyond

Environmental factors are involved in the etiology of autism spectrum disorder (ASD) and may contribute to the raise in its incidence rate. It is currently unknown whether the increasing use of nanoparticles such as titanium dioxide (TiO₂ NPs) in consumer products and biomedical applications may play a role in these associations. While nano-sized TiO₂ is generally regarded as safe and non-toxic, excessive exposure to TiO₂ NPs may be associated with negative health consequences especially when occurring during sensitive developmental periods. To test if prenatal exposure to TiO₂ NPs alters fetal development and behavioral functions relevant to ASD, C57Bl6/N dams were subjected to a single intravenous injection of a low (100 µg) or high (1000 µg) dose of TiO₂ NPs or vehicle solution on gestation day 9. ASD-related behavioral functions were assessed in the offspring using paradigms that index murine versions of ASD symptoms. Maternal exposure to TiO₂ NPs led to subtle and dose-dependent impairments in neonatal vocal communication and juvenile sociability, as well as a dose-dependent increase in prepulse inhibition of the acoustic startle reflex of both sexes. These behavioral alterations emerged in the absence of pregnancy complications. Prenatal exposure to TiO₂ NPs did not cause overt fetal malformations or changes in pregnancy outcomes, nor did it affect postnatal growth of the offspring. Taken together, our study provides a first set of preliminary data suggesting that prenatal exposure to nano-sized TiO₂ can induce behavioral deficits relevant to ASD and related neurodevelopmental disorders without inducing major changes in physiological development. If extended further, our preclinical findings may provide an incentive for epidemiological studies examining the role of prenatal TiO₂ NPs exposure in the etiology of ASD and other neurodevelopmental disorders.

The Effects of Housing Density on Social Interactions and Their Correlations with Serotonin in Rodents and Primates

Population density has been suggested to affect social interactions of individuals, but the underlying neural mechanisms remain unclear. In contrast, neurotransmission of monoamines such as serotonin (5-HT) and dopamine (DA) has been demonstrated to play important roles in social behaviors. Here, we investigated whether housing density affected social interactions of rodents and non-human primates housed in groups, and its correlations with monoamines. Japanese macaques exhibited higher plasma 5-HT, but not DA, concentrations than rhesus macaques. Similarly, C57BL/6 mice exhibited higher plasma and brain tissue 5-HT concentrations than DBA2 mice. Under crowding, C57BL/6 mice and Japanese macaques exhibited more prominent social avoidance with mates than DBA2 mice and rhesus macaques, respectively. Although DBA2 mice and rhesus macaques in crowding exhibited elevated plasma stress hormones, such stress hormone elevations associated with crowding were absent in C57BL/6 mice and Japanese macaques. Administration of parachlorophenylalanine, which inhibits 5-HT synthesis, increased social interactions and stress hormones in C57BL/6 mice under crowding. These results suggest that, animals with hyperserotonemia may exhibit social avoidance as an adaptive behavioral strategy to mitigate stress associated with crowding environments, which may also be relevant to psychiatric disorder such as autism spectrum disorder.

Developmental and behavioral alterations in zebrafish embryonically exposed to valproic acid (VPA): An aquatic model for autism

Autism spectrum disorder (ASD) has complex neurodevelopmental impairments and origins that are linked to both genetic and environmental factors. Hence, there is an urgency to establish animal models with ASD-like characteristics to understand the underlying mechanisms of ASD. Prenatal exposure to valproic acid (VPA) produced ASD-like symptoms in humans, rats, and recently zebrafish. The present study investigated the use of VPA exposure to generate an ASD model in zebrafish. Early life stage exposures produced ASD-like phenotypes in the developing brain development and behavioral changes in embryonic and larval zebrafish. Our findings revealed that treating zebrafish embryos with VPA starting at 8h post fertilization (hpf) resulted in significant: increase in the ASD macrocephalic phenotype; hyperactivity of embryo/larvae movement behaviors; and increases of ASD-like larval social behaviors. Further analysis showed increases in cell proliferation, the proportion of mature newborn neurons, and neural stem cell proliferation in the brain region, which may contribute to the brain overgrowth and macrocephaly observed following VPA exposure. Our study demonstrated that VPA exposure generates ASD-like phenotypes and behaviors, indicating that zebrafish is an alternative model to investigate underlying ASD mechanisms.

Childhood trauma is not a confounder of the overlap between autistic and schizotypal traits: A study in a non-clinical adult sample

Childhood trauma has been shown to be a robust risk factor for mental disorders, and may exacerbate schizotypal traits or contribute to autistic trait severity. However, little is known whether childhood trauma confounds the overlap between schizotypal traits and autistic traits. This study examined whether childhood trauma acts as a confounding variable in the overlap between autistic and schizotypal traits in a large non-clinical adult sample. A total of 2469 participants completed the Autism Spectrum Quotient (AQ), the Schizotypal Personality Questionnaire (SPQ), and the Childhood Trauma Questionnaire-Short Form. Correlation analysis showed that the majority of associations between AQ variables and SPQ variables were significant (p < 0.05). In the multiple regression models predicting scores on the AQ total, scores on the three SPQ subscales were significant predictors(Ps < 0.05). Scores on the Positive schizotypy and Negative schizotypy subscales were significant predictors in the multiple regression model predicting scores on the AQ Social Skill, AQ Attention Switching, AQ Attention to Detail, AQ Communication, and AQ Imagination subscales. The association between autistic and schizotypal traits could not be explained by shared variance in terms of exposure to childhood trauma. The findings point to important overlaps in the conceptualization of ASD and SSD, independent of childhood trauma.

Parental Action and Referral Patterns in Spatial Clusters of Childhood Autism Spectrum Disorder

Sociodemographic factors have long been associated with disparities in autism spectrum disorder (ASD) diagnosis. Studies that identified spatial clustering of cases have suggested the importance of information about ASD moving through social networks of parents. Yet there is no direct evidence of this mechanism. This study explores the help-seeking behaviors and referral pathways of parents of diagnosed children in Costa Rica, one of two countries in which spatial clusters of cases have been identified. We interviewed the parents of 54 diagnosed children and focused on social network connections that influenced parents' help seeking and referral pathways that led to assessment. Spatial clusters of cases appear to be a result of seeking private rather than public care, and private clinics are more likely to refer cases to the diagnosing hospital. The referring clinic rather than information spread appears to explain the disparities.

Inverse relationship between urban green space and childhood autism in California elementary school districts

Green space has a variety of health benefits. However, little is known about its impact on autism, the fastest-growing neurodevelopmental disorder in children. This study examined the relationship between green space and childhood autism prevalence. Autism count data in 2010 were obtained for 543 of ~560 public elementary school districts in California. Multiple types of green space were measured in each school district, including percentages of forest, grassland, and average tree canopy and near-road tree canopy. Their associations with autism prevalence were evaluated with negative binomial regression models and spatial regression models. We observed inverse associations between several green space metrics and autism prevalence in school districts with high road density, the highly urbanized areas, but not in others. According to negative binomial regression models, adjusted rate ratios (RR) for the relationships in these school districts between autism prevalence and green space metrics in 10% increments were as follows: for forest, RR=0.90 (95% confidence interval [CI]: 0.84-0.95); for grassland, RR=0.90 (95% CI: 0.83-0.97); for average tree canopy, RR=0.89 (95% CI: 0.83-0.95), and for near-road tree canopy, RR=0.81 (95% CI: 0.73-0.91). These results suggest that increases of 10% in forest, grassland, average tree canopy and near-road tree canopy are associated with a decrease in autism prevalence of 10%, 10% 11% and 19%, respectively. In contrast, urban land and road density were positively associated with autism prevalence. The results of spatial regression models were consistent with those obtained by negative binomial models, except for grassland. Our study suggests that green space, specifically tree cover in areas with high road density, may influence autism prevalence in elementary school children beneficially. Further studies are needed to investigate a potential causal relationship, and the major mechanisms that may underlie the beneficial associations with green space, such as buffering traffic-related air pollution and noise.