Risk factors of autism spectrum disorders in preschool children: a case–control study

Background Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by abnormalities in social relationships and restricted or repetitive behavioral patterns. Aim To evaluate the prevalence among children and the risk factors of ASD to improve subsequent early diagnosis and intervention. Patients and methods This case–control study involved 125 children with ASD according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, who were selected from the outpatient clinic of Neuropsychiatry Department, and The Center of Psychiatry, Neurology and Neurosurgery, Tanta University Hospital. The childhood autism rating scale questionnaire and the risk factor assessment questionnaire were used for assessment of the studied children. Results The feeding type was significantly different between both groups ( P =0.003). The ASD group had significantly lower folic acid supplementation compared with controls ( P =0.013), and a significantly higher prevalence of family history of psychiatric diseases than controls ( P =0.040). Moreover, the ASD group had significantly lower intelligence quotient according to Stanford Binet test 5th edition than controls ( P <0.001), while had a significantly higher childhood autism rating scale score than controls ( P <0.001). Conclusion Multiple risk factors contribute to the high ASD prevalence among preschool children. The feeding type of neonates is considered a major neonatal risk factor. In addition, lack of maternal folic acid supplementations and a family history of psychiatric diseases increase the risk for ASD.