BackgroundFew epidemiological data on autism spectrum disorders (ASD) exist for Arabic countries. We conducted the first survey of ASD in Qatar, a population with high consanguinity level.MethodsThis cross‐sectional survey was conducted from 2015 to 2018 in Qatar school‐age children (N = 176,960) from national and immigrant families. Children diagnosed with ASD were identified through medical centers and special needs schools. Records were abstracted and supplemented by parental interviews. Additionally, children attending 93 schools were screened; ASD case status was confirmed in random samples of screen‐positive and screen‐negative children. Prevalence was estimated after taking into account different sampling fractions and participation rates at each survey phase.ResultsOne thousand three hundred and ninety‐three children already diagnosed with ASD were identified. Among 9,074 school survey participants, 760 screen‐negative children and 163 screen‐positive children were evaluated; 17 were confirmed to have ASD including five children newly diagnosed. Prevalence was 1.14% (95% CI: 0.89–1.46) among 6‐ to 11‐year‐olds. ASD was reported in full siblings/extended relatives in 5.9% (95% CI: 0.042–0.080)/11.8% (95% CI: 0.095–0.146) families. First‐degree consanguinity in Qatari cases (45%) was comparable to known population levels. Among 844 ASD cases (mean age: 7.2 years; 81% male), most children experienced language delay (words: 75.1%; phrase speech: 91.4%), and 19.4% reported developmental regression. At the time of the survey, persisting deficits in expressive language (19.4%) and peer interactions (14.0%) were reported in conjunction with behavioral problems (ADHD: 30.2%; anxiety: 11.0%). In multivariate logistic regression, ASD severity was associated with parental consanguinity, gestational diabetes, delay in walking, and developmental regression.ConclusionsASD prevalence in Qatar is consistent with recent international studies. The methods employed in this study should help designing comparable surveys in the region. We estimated that 187,000 youths under age 20 have ASD in Gulf countries. This figure should assist in planning health and educational services for a young, fast‐growing population.

Validated screening and diagnostic tools for autism spectrum disorder for use in Arabic-speaking individuals are scarce. This study validated the Arabic version of the Social Communication Questionnaire. The total study sample included 206 children with autism spectrum disorder and 206 typically developing children (73.8% male; mean age: 8.5 (standard deviation = 2.6) years). The mean Social Communication Questionnaire total score was significantly higher in autism spectrum disorder children than in typically developing children ( p < 0.0001). Scores on the three Social Communication Questionnaire subscales also differed significantly between the groups ( p < 0.001). Of the 39 items, 37 were endorsed significantly more often in the autism spectrum disorder group. The total Social Communication Questionnaire score did not vary by age or gender. Internal consistency was excellent (alpha = 0.92). In the receiver operating characteristic analysis, the area under the curve for the total score showed excellent discrimination between autism spectrum disorder and typically developing children (area under the curve = 0.95; 95% confidence interval: 0.93–0.97). The areas under the curve for the scale subscores were 0.923 (95% confidence interval: 0.898–0.949) for the social interaction score, 0.872 (95% confidence interval: 0.838–0.905) for the communication score, and 0.856 (95% confidence interval: 0.819–0.893) for the repetitive behaviors score. The findings support the use of the Arabic Social Communication Questionnaire to successfully differentiate children with clinically diagnosed autism spectrum disorder using the established cutoff value for the English version.

The primary objectives of this study were to evaluate the structure and age‐related stability of social attention in English and Arabic‐speaking youth and to compare social attention between children with autism spectrum disorder (ASD), other developmental disabilities (DD), and typically‐developing controls. Eye‐tracking data were collected from US (N = 270) and Qatari (N = 242) youth ages 1–17, including children evaluated for possible ASD. Participants viewed 44 stimuli from seven social paradigms. Fixation was computed for areas of interest within each stimulus. Latent variable models examined the structure of social attention. Generalized estimating equation models examined the effect of age, sex, culture, and diagnostic group on social attention. The best‐fitting model included a general social attention factor and six specific factors. Cultural differences in social attention were minimal and social attention was stable across age (r = 0.03), but females showed significantly greater social attention than males (d = 0.28). Social attention was weaker in DD (d = −0.17) and lowest in ASD (d = −0.38) relative to controls. Differences were of sufficient magnitude across areas‐of‐interest to reliably differentiate DD from controls (AUC = 0.80) and ASD‐only from all other cases (AUC = 0.76). A social attention dimension that represents an early‐life preference for socially salient information was identified. This preference was cross‐culturally consistent and stable across development but stronger in females and weaker in DD, especially ASD. Given rapid and easy‐to‐collect remote eye tracking administration, social attention measurement may be useful for developmental monitoring. Acquisition of population norms, analogous to height/weight/head circumference, might enhance early screening and tracking of neurodevelopment. Lay Summary This research found that social attention is a single dimension of behavior that represents a strong preference for social stimuli, is consistent across cultures, stable across age, and stronger in females. Children with developmental disabilities had lower levels of social attention than neurotypical children and children with autism spectrum disorder had the lowest levels of social attention.

Extracellular vesicles (EVs) are membrane vesicles released from cells to the extracellular space, involved in cell-to-cell communication by the horizontal transfer of biomolecules such as proteins and RNA. Because EVs can cross the blood-brain barrier (BBB), circulating through the bloodstream and reflecting the cell of origin in terms of disease prognosis and severity, the contents of plasma EVs provide non-invasive biomarkers for neurological disorders. However, neuronal EV markers in blood plasma remain unclear. EVs are very heterogeneous in size and contents, thus bulk analyses of heterogeneous plasma EVs using Western blot and ELISA have limited utility. In this study, using flow cytometry to analyze individual neuronal EVs, we show that our plasma EVs isolated by size exclusion chromatography are mainly CD63-positive exosomes of endosomal origin. As a neuronal EV marker, neural cell adhesion molecule (NCAM) is highly enriched in EVs released from induced pluripotent stem cells (iPSCs)-derived cortical neurons and brain organoids. We identified the subpopulations of plasma EVs that contain NCAM using flow cytometry-based individual EV analysis. Our results suggest that plasma NCAM-positive neuronal EVs can be used to discover biomarkers for neurological disorders.