Autism in India: a case–control study to understand the association between socio-economic and environmental risk factors

  • Bharathi GeethaEmail author
  • Chinnaraju Sukumar
  • Eswaran Dhivyadeepa
  • Janardhana Kumar Reddy
  • Vellingiri BalachandarEmail author
Original article


Autism spectrum disorder is a neurodevelopmental disorder and the cause of autism is still unclear. The aim of this study was to investigate the association of socioeconomic, environmental, pregnancy and newborn-related risk factors among children with autism spectrum disorders. This was a population-based case–control study. The study included 55 children with autism spectrum disorder and 55 age and sex matched typically developing normal children (TD) between 3 and 12 years. Several socio-economic factors, environmental factors, pregnancy related, natal, post-natal factors and the first noticed signs by the parents were analyzed. Chi-square test was used to compare nominal variables. For multivariate analysis, forward stepwise logistic regression model was employed to examine the association between autism and the chances that the child develops ASD to assess the odds ratios. Male predominance was observed in the study. Logistic regression model showed statistical significance of the following factors: paternal age greater than 40 years, family history of autism, nutrition during pregnancy, mode of labor, fetal hypoxia, NICU stay and history of breast feeding. In this epidemiological study of autism in Coimbatore city, we found correlation between several environmental factors during fetal development and can be transmitted to succeeding generations, causing atypical behavior phenotypes. The exact exposure magnitude, exposure time in relation to vital developmental periods need to be studied to understand the influence of socioeconomic and environmental factors, which can be improved to prevent ASD-related challenges.


Autism Socio-economic Environment Risk factors Parental age 



We would like to thank the school authorities and the state government officials for giving the necessary permission to carry out the present study.


This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Compliance with ethical standards

Conflict of interest

No authors declare any conflict of interest.

Ethics approval

All procedures performed in this study were in accordance with the ethical standards of the Institutional research committee and with the 1964 Helsinki declaration and its comparable ethical standards.

Informed consent

Informed consent was obtained from all participants.


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Copyright information

© Belgian Neurological Society 2018

Authors and Affiliations

  1. 1.Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular BiologyBharathiar UniversityCoimbatoreIndia
  2. 2.Department of EducationBharathiar UniversityCoimbatoreIndia

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