An intubated premature female infant born at roughly 27 weeks gestation, weighing 990 grams. New research suggests premature babies are five times more likely to develop an autism spectrum disorder than babies who reach full gestation.
Credit: wikimedia commons
WASHINGTON: Undersized babies born earlier than expected are five times more likely than normal infants to develop autism, according to a two-decade-long U.S. study.
Premature babies have long been known to risk a host of health problems and cognitive delays, but the study in the journal Pediatrics is the first to establish a link between low birth weight and autism.
"As survival of the smallest and most immature babies improves, impaired survivors represent an increasing public health challenge," said lead author and epidemiologist Jennifer Pinto-Martin. "Cognitive problems in these children may mask underlying autism."
Pinto-Martin is director of the Center for Autism and Developmental Disabilities Research and Epidemiology at the University of Pennsylvania School of Nursing.
Underlying autism
U.S. researchers tracked 862 children from birth to young adulthood - a period of more then 20 years. Those in the study were born between 1984 and 1987 in three counties in New Jersey. The children weighed between 500 and 2,000 grams at birth.
Screening of these children at age 16 as part of a larger psychiatric follow up revealed that 117 of 623 patients showed positive results for autism spectrum disorders - roughly 18%.
Diagnostic testing was also done on a proportion of the patients who screened positives (about 60%) and those that screen negatives (24%) at age 21. Of 70 who screened positive as adolescents, 11 (14.3%) were confirmed as having autism spectrum disorders.
Using these screening and diagnostic follow-ups, the researchers estimated a 5% prevalence of autism for premature babies - compared to just 1% prevalence in the general population.
Early intervention important for development
Pinto-Martin said parents who suspect autism should get their children screened. "Early intervention improves long-term outcome and can help these children both at school and at home," she noted.
Autism is the term for an array of conditions ranging from poor social interaction to repetitive behaviors and entrenched silence.
The condition is rare, predominantly affecting boys, and its causes are fiercely debated. The study was funded with $3 million from the U.S. National Institute for Mental Health.
