Hefty Toll for Autistic Children
Childhood obesity continues to be a concern for parents and healthcare providers alike. Nearly 19% of children in the U.S. aged 2 to 18 years old are overweight or obese, according to the latest statistics from the National Health and Nutrition Examination Survey. Overweight and obesity at younger ages place children at risk for serious physical and mental health concerns, such as Type 2 Diabetes or heart disease, as well as bullying.
In the recent years, overweight and obesity have emerged as important issues among autism researchers. In an effort to gain a deeper understanding of this issue, scientists from the Center for Autism Research (CAR) and the University of Pennsylvania (Penn) have evaluated data from the on-going, Study to Explore Early Development (SEED), a multi-site study of children 2-5 years old including 668 children with a diagnosis of autism spectrum disorder (ASD), 914 children with developmental delays, and 884 children with neither ASD nor developmental delays as a control group.
Their search to grasp a better understanding of overweight/ obesity in autistic** children has led to concerning findings. In the first of two separate studies, CHOP’s Susan Levy, MD, MPH, examined the rates of overweight/obesity, finding that for children with ASD, the risk of being overweight or obese was 1.57 times higher than controls in the general population, and 1.38 times higher than children with developmental delays. This research, published in the Journal of Pediatrics, also found children with more severe symptoms of ASD were 1.7 times more likely to be overweight/obese than children with milder symptoms. However, Dr. Levy and her team noted that common co-occurring conditions in ASD, such as endocrine or genetic disorders, asthma, or gastrointestinal conditions, may affect a child’s weight and increase the likelihood for weight gain.
“Our study encourages parents and clinicians to keep a watchful eye on a child’s weight, even from a young age,” says Dr. Levy, CAR’s medical director. “We still need additional research to uncover the specific factors contributing to the risk of overweight/obesity in autistic children and to determine what interventions strategies would be most beneficial for children.”
In the second of two studies, Tanja Kral, PhD, Associate Professor of Nutrition Science at Penn Nursing, looked at early life risk factors for childhood obesity, including maternal pre-pregnancy weight status, weight gain during pregnancy, and rapid weight gain during infancy. Dr. Kral’s team found that across all groups, mothers with pre-pregnancy overweight or obesity were almost 2.5 times more likely to have a child with overweight or obesity at ages 2-5 years than other mothers. Similarly, the risk for childhood obesity was 1.5 times greater for mothers who gained more than the recommended amount of weight during pregnancy. The findings further revealed that autistic children showed the highest frequency of rapid weight gain in the first 6 month of life. Autistic children with rapid weight gain during infancy had 3.5 times greater chances of developing overweight or obesity during childhood.
“We still need to determine what causes some children to be at greater risk of rapid weight gain,” says Dr. Kral. “It’s really important to foster healthy growth patterns during infancy, as we do not know which children will go on to have an ASD diagnosis. For children in high risk populations, such as premature infants, younger siblings of children with ASD, children with a genetic predisposition to ASD, we should monitor growth patterns at an early age.”
Previous research has suggested lower levels of physical activity and restricted food choices could be likely contributing factors. “Like ASD itself, it’s likely a complex matrix of genetic and environmental factors are contributing to the risk of obesity in autistic children and we need to continue to research this issue to determine what those factors are and which children are at highest risk”, explains Dr. Levy.
** Please note, CAR uses both person-first and identity- first language. Recent research has demonstrated that “autistic” is the preferred term in the autism community, with many others preferring “on the autism spectrum” or “person with autism”(Kenny et al., 2016, "Which terms should be used to describe autism? Perspectives from the UK autism community" Autism).