Research suggests that individuals with ASD are at higher risk of early death than the general population. Previous studies have suggested that this increased risk may be associated with intentional and unintentional injuries, however these studies have been limited by population size and location. The goal of this study was to examine the causes of death in a large population of individuals with ASD in the U.S. who died between 1999 and 2014.

The researchers reviewed death records in the National Vital Statistics System, a database that contains information about causes of death and demographics. In the time frame of the study, there were 1,367 recorded deaths of individuals with diagnosed ASD (1,043 males and 324 females). The average age at death of these individuals was 36.2 years, as compared to an average age at death of 72 years across the general population.

Although previous studies have examined the relationship between premature mortality and ASD, few have focused on injury as a contributor to the high mortality rate among those with ASD. In this study, the researchers discovered that individuals with ASD were three times more likely than the general population to have died due to an unintentional injury. Overall, unintentional injury accounted for 27% of recorded deaths. Suffocation, asphyxiation, and drowning accounted for 79.4% of all injury-related death in children with ASD, and children younger than 15 years old were at elevated risk.

There may still be a significant underreporting of ASD-related deaths, especially deaths from unintentional injury. Therefore, these results present a public health concern and the researchers propose the development and implementation of prevention approaches, such as swimming lessons, to decrease these risks in individuals with ASD, particularly those who are younger than 15 years old.