Prevalence of Autism and its Comorbidities and the Relationship with Maternal Psychopathology: A National Population-Based Study.

Background: There is no clear picture regarding the prevalence rates of autism and its comorbidities among Iranian children and adolescents. The present study aimed to estimate these rates as part of a large national population-based study on epidemiology of psychiatric disorders in Iranian children and adolescents.

Methods: The total sample consisted of 31000 children and adolescents between 6 to 18 years of age. The Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Present and Life time version (K-SADS-PL) was used as the diagnostic tool.

Results: The prevalence of autism in the total sample is equal to 0.1% (10 per 10000), with a 2:1 male-to-female ratio. In total, 86% of people with autism had at least one comorbid condition. Intellectual disability, epilepsy, enuresis and attention deficit and hyperactivity disorder (ADHD) with prevalence rates of 70.3%, 29.7%, 27% and 21.62%, respectively, were the most prevalent comorbid conditions in people with autism. Maternal personality disorders were also shown to be associated with increasing risk of autism.

Conclusion: The present study shows high prevalence rates for autism and its comorbid conditions among Iranian children and adolescents. It also reveals that there is a relationship between some maternal psychiatric disorders and the risk of autism.