A new study from the Karolinksa Institute in Sweden reports some troubling news for people with autism spectrum disorder (ASD). The researchers discovered that people with ASD are more likely to die young, with certain subgroups of people with ASD dying up to 30 years earlier than expected. The news is stark, especially considering that the CDC estimates that 1 in 68 people in the United States have ASD.
The researchers drew data from Sweden’s national health registries. They evaluated 27,000 people with ASD and about 2.5 million without ASD. The researchers considered individuals’ cause of death, age at death, and other factors, like whether they had other disabilities in addition to ASD.
For adults with ASD, the risk of premature death is due to suicide. This is in contrast to the general population, in which heart disease and cancer are among the top killers. Overall, adults with ASD and no additional learning disability were nine times more likely to commit suicide than adults in the general population.
The age at which people with ASD died was related to their cognitive abilities. Individuals with both ASD and a learning disability died, on average, 30 years earlier than those without ASD and learning disabilities. Individuals with just ASD died an average of 12 years earlier than those without ASD.
Even people diagnosed with “high-functioning” autism (formerly diagnosed as Asperger’s syndrome, before the diagnostic criteria changed) were not free from the risk of early mortality. Individuals with high-functioning autism were twice as likely to die young than individuals without ASD.
This pattern held for both males and females on the spectrum; however, women with learning disabilities had the highest risk of death compared to any group in the study.
The study does not address why people with ASD are more likely to commit suicide than their peers. Although some suggest that social and biological factors may contribute to the risk.
This research is published in the British Journal of Psychiatry.