Mortality in Autism

The long-term objective of the proposed project is to reduce excess mortality and improve life expectancy for people with autism spectrum disorder (ASD). The specific aims are to: 1) determine age- and sex-specific mortality risk in Medicaid beneficiaries with and without ASD; 2) examine cause-specific mortality risk in Medicaid beneficiaries with and without ASD; 3) identify effect modifiers (e.g., gender and intellectual disability) of mortality risk associated with ASD; and 4) assess racial and ethnic disparities in mortality risk in Medicaid beneficiaries with and without ASD. In the United States, the reported prevalence of ASD among children aged 8 years has more than tripled over the past two decades, increasing from 6.7 per 1,000 in 2000 to 23.0 per 1000 in 2018. There were an estimated 6.9 million persons with ASD in the United States, including over 1.5 million children aged 3-17 years and 5.4 million adults aged 18-84 years. As a complex neurodevelopmental disability, ASD often requires extensive lifetime health care and social services. Research on ASD has been largely concentrated in understanding its biology, identifying risk factors, monitoring prevalence in children, and evaluating treatments and interventions. Although substantially reduced life expectancy for individuals with ASD has been speculated since the early 1990s, research on mortality and lifespan issues in autism remains scant. Medicaid, including the Children’s Health Insurance Program, is the primary public insurance program for individuals with ASD. The proposed project involves constructing a dynamic cohort of about 1 million Medicaid beneficiaries with ASD and about 4 million Medicaid beneficiaries without ASD (two million matched with the exposed cohort on state, year of enrollment, age at enrollment, and sex; and two million matched additionally on type of eligibility) and analyzing longitudinal data over a 24-year study period (1999–2022). Results from the proposed project will provide much-needed epidemiologic evidence for understanding the life- course mortality risk, causes of death, effect modifiers of mortality risk, and racial and ethnic disparities in mortality risk associated with ASD, and for developing effective interventions to reduce excess mortality and informing health policy and service planning for people with ASD.