Mortality of Children with Autism Spectrum Disorder Using Data from a Large-Scale Korean National Cohort.

Purpose This study aimed to investigate the association between autism spectrum disorder (ASD) diagnosis and mortality among children using the data from a large-scale national cohort of Korean infants and children. We also explored the association between hearing impairment detected during early infancy and mortality. Materials and methods We performed a retrospective cohort study using the nationwide claims data of the Republic of Korea. Children born between 2007 and 2014 (n=3598904) were followed up until 2020. Cox proportional hazard models were used to examine the association between ASD diagnosis and mortality among children. Then, in order to evaluate the association between hearing impairment and mortality, Cox proportional hazard models were built using the responses related to hearing impairment asked during the first health screening (at age 4-6 months). Results Of the 3598904 children born between 2007 and 2014, 32878 children (0.9%) were diagnosed with ASD until the end of 2020. We identified that ASD diagnosis was associated with higher mortality among children [hazard ratio (HR)=2.5, 95% confidence interval (CI): 2.2-2.9]. This association was stronger among girls (HR=4.8, 95% CI: 3.9-5.8) compared to boys (HR=1.9, 95% CI: 1.6-2.2). We found that hearing impairment detected during infancy was associated with higher mortality among children with ASD diagnosis. Conclusion ASD diagnosis was associated with higher mortality among Korean children. This association was stronger in girls than in boys. Hearing impairment detected during infancy was also associated with higher mortality among children diagnosed with ASD.