Risk Factors for Autism Spectrum Disorders in the State of Qatar

Background

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder generally manifesting in the first years of life and tending to persist into adolescence and adulthood. It is characterized by deficits in communication and social interaction, and in restricted, repetitive patterns of behavior, interests, and activities. It is a disorder with multifactorial etiology. The majority of ASD cases (85%) is idiopathic and have no known genetic causes. In these cases, it is likely that a combination of multiple genetic and non-genetic factors interacts and resulting in ASDs. This study aims to identify the common risk factors associated with ASD among Qatari and non-Qatari children.

Methods

A retrospective, cross-sectional review of 114 ASD medical was conducted. Detailed clinical and genetic data were collected retrospectively. Results: The total sample consisted of 114 patients with ASD. There were 25 (21.9%) females and 89 (78%) males, aged 1– 14 years (mean: 8.65 years, standard deviation (SD): 2.14) from 90 families. Of those studied, 37 (32.5%) were Qatari, and 77 (67.5%) were non-Qatari. ASD diagnosis was confirmed using the Autism Diagnostic Observation Schedule (ADOS), the Autism Diagnostic Interview- Revised (ADI-R), and the Statistical Manual of Mental Disorders (DSM). Age at diagnosis was 1– 11 years (mean: 3.66 years, SD: 1.49). Consanguinity was found in 49 (43%) of the 114 patients, of which 22 (19.2%) were Qatari and 27 (23.6%) non-Qatari. Twenty-nine (59%) of the 49 were first cousins, and the remaining were either second cousins or from the same tribe. Of the 114 patients, 11 (9.6%) had a family history of ASD. Eight (7%) were Qatari, and three (2.6%) were non-Qatari. Twenty-nine (25.4%) ASD patients presented with a speech delay and poor communication, which was observed more in non-Qatari compared to Qatari patients. A total of 10/114 (8.7%) were Qatari compared to 19/114 (16.6%) who were non-Qatari. Comorbid conditions were identified in 109 (95.6%) of the 114 ASD patients. Thirty-five patients (32.1%) had a learning disability, of which 25 (22.9%) were Qatari and 10 (9.1%) non-Qatari. Thirty-two (29.4%) patients had gastroenteritis. Of the babies in the study, 17 (80.9%) had hypoxia, four of which (19%) were Qatari and 13 (61.9%) non-Qatari. Forty-six (50.5%) of the babies had upper respiratory tract infections during the first two years of life (18 [39%] were Qatari, and 28 [30%] were non-Qatari). During pregnancy, the mothers of 64 (56.1%) of the 114 patients had maternal gestational diabetes, 27 (23.6%) of which were Qatari and 37 (32.4%) non-Qatari. Of 101 patients, 55 (54.5%) of the mothers had vitamin D deficiency, 37 (36.6%) of which were Qatari and 18 (17.8%) non-Qatari.

Discussion

The average age of incidence of ASD in the Qatar population was 3.6. ASD is more common in males than females (4:1) as girls have a protective effect from developing autism. The most common clinical features at diagnosis of ASD were speech delay, infection, learning disability, and/or gastroenteritis. In addition, the common maternal health problem during pregnancy was gestational diabetes and vitamin D deficiency.

Conclusions

The most common risk factors of ASD in Qatar are maternal gestational diabetes and vitamin D deficiency during pregnancy and hypoxia as a birth complication. Thus, there is a need to increase awareness of ASD in children and adults and to establish comprehensive services, including training doctors, nurses, and dietitians, to meet the demands for the growing number of ASD patients in the Qatar population.