Prevalence and correlates of autism spectrum disorder in Qatar: a national study

Background: Few 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. Methods: This 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. Results: One 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. Conclusions: ASD 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.