Autism spectrum disorders are characterized by abnormal neural development that cause impaired social interaction, impaired communication, and restricted and repetitive behavior. These symptoms are usually identified before the child is three years old, and become more manifest as development continues. The three disorders that are included in this group are autism, Asperger syndrome, and pervasive developmental disorder. There is a strong genetic component that contributes to the risk for the development of these disorders, but environmental factors have also been thought to contribute to the etiology of these disorders. Researchers from the University of Pennsylvania, lead by Dr. Jennifer A. Pinto-Martin, have provided evidence that prematurity and low birth weight is associated with increased risk of developing autism spectrum disorder. The results of their research were published online in the journal Pediatrics. The researchers sought to estimate the diagnostic prevalence of autism spectrum disorder in a cohort of low birth weight individuals. The researchers used a population based study involving 1,105 individuals born weighting less than 2,000 grams between 1984 and 1989 in central New Jersey. The study participants were followed up periodically to the age of 21 years, and screened for autism spectrum disorders. The screening involved previous professional diagnosis or a score above a liberal cutoff on the Social Communication Questionnaire or the Autism Spectrum Symptoms Questionnaire. The researchers found that the estimated prevalence rate of autism spectrum disorder in the low birth weight cohort was 5%. This was markedly greater than the prevalence among the general population of 0.9%, as reported by the Centers for Disease Control and Prevention. The authors wrote, “This is the first study to have estimated the prevalence of [autism spectrum disorder] in a prospectively followed [low birth weight] population using research validated diagnostic instruments. [Autism spectrum disorder] prevalence in this US population representative cohort of [low birth weight] (<2000 g) adolescents was estimated to be 5%, a fivefold increase over that reported by the Centers for Disease Control and Prevention for 8-year-olds in the US general population in 2006 (0.9%)”. This study is important because it will help identify those individuals that may be at increased risk of developing autism spectrum disorder. Early identification and diagnosis may aide in providing treatment sooner which may result in better outcomes for these individuals.
Jennifer A. Pinto-Martin et al. “Prevalence of Autism Spectrum Disorder in Adolescents Born Weighing <2000 Grams” Pediatrics originally published online October 17, 2011 DOI: 10.1542/peds.2010-2846