AUTISM SPECTRUM DISORDER AND POSTNATAL FACTORS: A CASE-CONTROL STUDY IN BRAZIL

ABSTRACT Objective: To estimate the magnitude of the association between Autism Spectrum Disorder (ASD) and postnatal factors in a Brazilian population. Methods: A case-control study was performed with 253 individuals diagnosed with ASD and 886 individuals without signs of the disorder. A semi-structured questionnaire and the multiple logistic regression model were adopted in the data analysis. To estimate the magnitude of associations, the crude and adjusted Odds Ratio (OR) was used. Results: An association with the following factors was found: having been born with congenital malformation (OR 4.24; confidence interval of 95% - 95%CI 1.92-9.34), neonatal jaundice (OR 1.43; 95%CI 1.01-2.02), absence of crying at birth and seizure episode in childhood (OR 5.75; 95%CI 3.37-9.81). The magnitude of the association was higher in the children/adolescents who had two or more postnatal complications (OR 6.39; 95%CI 4.10-10.00). Conclusions: The findings of the present study suggest that malformation, neonatal jaundice, absence of crying at birth and seizure episodes in childhood are important factors to be considered when studying the etiology of ASD.