By Dennis Thompson
Analysis of death records found that kids with an autism spectrum disorder are 160 times more likely to die from drowning compared with the general pediatric population, the researchers reported.
Children diagnosed with autism -- usually between 2 and 3 years of age -- need swimming lessons as soon as possible, even before they start other therapies that will improve the long-term quality of their lives, said senior author Dr. Guohua Li.
"Pediatricians and parents should immediately help enroll the child in swimming classes, before any behavioral therapy, speech therapy or occupational therapy," said Li. He is a professor of epidemiology at Columbia University's Mailman School of Public Health in New York City.
"Swimming ability for kids with autism is an imperative survival skill," he added.
Li and his team made their discovery while reviewing over 32 million death certificates in the U.S. National Vital Statistics System. The investigators identified nearly 1,370 people diagnosed with autism who died between 1999 and 2014.
Overall, someone with autism is three times more likely to suffer an unintentional injury-related death, the study found.
People diagnosed with autism also die at an average age of 36, compared with age 72 for the general population, Li and his colleagues noted.
More than one-quarter of deaths among people with autism occur due to injury, most often by suffocation, asphyxiation or drowning, the findings showed.
Kids bear the brunt of this risk. Together, those three types of injury accounted for nearly 80 percent of total injury deaths in children with autism, Li said.
Children with autism are apt to wander near bodies of water, especially when they are feeling anxious, Li pointed out.
"They tend to have an affinity to water bodies -- like pools or ponds or rivers," he said. "They need to touch or feel the water to get that kind of calming effect, so they wade into the water and they drown."
Autism is a serious neurodevelopmental disorder that affects one in 68 U.S. children, according to the U.S. Centers for Disease Control and Prevention. Symptoms vary, but autism generally causes difficulties with communication and relationships.
The researchers also found that the annual number of deaths for individuals diagnosed with autism has risen nearly seven times from 1999 to 2014.
However, Li attributes that to increased detection and diagnosis of autism rather than anything related to autism itself.
"The diagnosis rate has increased in the past two decades, and you would expect a similar increase in mortality among individuals with autism," Li said.
Suffocation and asphyxiation are more common among adults with autism, Li said, adding that further research is needed to figure out why this occurs.
Michael Rosanoff, director of public health research at Autism Speaks, agreed that the steep increase in deaths for people with autism is "most likely due to the increase in the number of autism diagnoses during that same time period."
The finding that people with autism have an average age at death that is half that of people in the general population also supports previous research, which has shown they're two to 10 times more likely to die prematurely, Rosanoff said.
"Autism alone is not a cause of death," Rosanoff said. "Rather, it is the common co-occurring medical and psychiatric conditions that play a role in increasing risk. These include schizophrenia, attention-deficit/hyperactivity disorder, epilepsy and depression."
Finally, Rosanoff noted that nearly half of kids with autism tend to wander, and drowning is the leading cause of death among people with autism who have wandered.
"Research like this is helping us better understand the specific causes -- in this case common injury-related causes -- of death that may be avoidable and preventable with appropriate interventions," he said. "For example, teaching water safety to children with autism is important."
The study findings were published online March 21 in the American Journal of Public Health.