Experts urge doctors to monitor these patients, particularly children, for signs of cardiometabolic disease.
People with autism spectrum disorder are at a greater risk of both type 1 and type 2 diabetes than nonautistic people, and children appear to be at the highest risk.
“This new publication adds to a growing body of literature suggesting that autistic people have a much broader range of physical health problems than previously thought,” UK autism expert Dr Elizabeth Weir wrote in an accompanying editorial.
The systematic review and meta-analysis of 34 studies found that, across all age groups, autism was associated with a 57% greater risk of developing diabetes overall. This included a 64% higher risk of type 1 diabetes and 247% higher risk of type 2 diabetes.
Autism was also associated with a 69% higher risk of dyslipidaemia and 46% higher risk of atherosclerotic heart disease, but there appeared to be no significant increased risk of hypertension, macrovascular disease or stroke, the study in JAMA Pediatrics found.
Children appeared to be even more affected by diabetes and hypertension than adults, the study of eight million people found.
Those with autism had 2.8 times the rate of diabetes and 2.5 times the rate of hypertension than children without autism.
The study authors urged clinicians to monitor patients with autism for early signs of cardiometabolic disease and their complications.
“Physicians should evaluate children with autism more vigilantly and maybe start screening them earlier than the usual,” they said.
The association between autism and cardiometabolic disease has long been suspected, but this paper provided the first empirical evidence to validate clinical observations over many years, said Professor Andrew Whitehouse, autism researcher from Western Australia, who was not involved in the research.
“Without a doubt one of the greatest contributing factors to these findings would be the rise of overweight and obesity in the autistic population,” said Professor Whitehouse, CliniKids director at Telethon Kids and the University of Western Australia.
“This study provides concrete evidence that the health troubles we’re seeing in terms of weight of autistic kids and adults is also playing out more broadly in terms of physical health.
“None of these are startling figures, but they are a call to action.”
Professor Whitehouse said it was unclear why there was an increased rate of type 1 diabetes among people with autism.
“It could be that there is a common genetic and/or environmental factor that is shared between both autism and Type 1 diabetes. However, at this time the reason for the link remains unclear.”
Professor Whitehouse said the findings emphasised the importance of preventative health programs and cardiometabolic monitoring for children with autism.
“We really need to start targeting preventative programs to autistic kids very early in life so we can get those healthy patterns of diet and physical activity.”
Nevertheless, he said there was no evidence that the genetic factors that led to autism were the same genetic factors that may cause metabolic conditions.
The study authors also suggested physicians think twice before prescribing medications such as olanzapine that were known to have metabolic adverse effects.
“Our findings should also be an eye opener for patients with autism and parents of kids with autism to simply be mindful about the higher risk of developing obesity and metabolic complications,” they said.
“Then they can talk with their physicians about strategies to prevent obesity and metabolic disease.”
