A new study published in JAMA Network Open finds that autistic individuals enrolled in Medicaid have a life expectancy of 64.9 years at birth, about 5.6 years shorter than the overall Medicaid population and roughly 13.8 years shorter than the general United States population.
Researchers analysed nationwide Medicaid data and linked it with the National Death Index to form a dataset covering all beneficiaries across the 50 states and the District of Columbia between 2000 and 2020. The study focused on 2,048,046 Medicaid beneficiaries diagnosed with autism, a group that was predominantly male (around 76 per cent) with females accounting for about 24 per cent.
Lead researcher Guohua Li, a professor of epidemiology and anaesthesiology at the Columbia University Irving Medical Center, emphasised the novelty of the finding. “It has been speculated since the late 1980s that autism might shorten life expectancy,” he said. “Due to inadequate sample sizes and age-specific mortality data, life expectancy for the autistic population remained unknown.”
“Life expectancy is the most important indicator of the overall health status for a defined population,” Li added. “Our study is the first in time to determine the life expectancy for the autistic population.”
When broken down by gender, the study found that autistic men lived an average of 64.6 years and autistic women 65.0 years. However, because women generally outlive men in the wider population, the relative life expectancy deficit was larger for autistic women: 16 years versus the general United States female population, compared with 11.6 years for autistic men against the general United States male population.
Over the two decades covered by the study, life expectancy for autistic Medicaid beneficiaries rose slightly—from 63.9 years in the early 2000s to 65.6 years by the late 2010s. The first year of the COVID-19 pandemic, 2020, saw a broad drop in life expectancy across the United States; autistic individuals on Medicaid experienced the largest decline, losing 4.1 years of life expectancy relative to the previous five-year period.
“The impact of the COVID-19 pandemic on life expectancy for the autistic population was twice as much as for the general population, which underscores the exceptional vulnerability of this growing population group with special needs,” Li noted.
Key causes and risks
Beyond overall mortality, the researchers identified specific health problems contributing to early deaths. They found that autistic individuals on Medicaid had a 44 per cent higher overall risk of death compared with the general Medicaid population, with deaths arising from a range of illnesses and accidents rather than a single cause.
Li highlighted several preventable factors: “Autistic people are at heightened risk of premature death due in large part to preventable causes such as influenza, malnutrition, pneumonia, and drowning.”
In particular, deaths from influenza were more than ten times higher than expected for the Medicaid population, malnutrition deaths were seven and a half times higher, pneumonitis linked to inhaling food or liquid into the lungs occurred nearly seven times more often, and fatalities from accidental drowning occurred more than three times as often as expected.
Li described the finding on malnutrition as “sadly surprising,” suggesting that neglect, maltreatment, poverty and impaired self-care could underlie this trend.
As with many studies, certain limitations apply. Medicaid serves primarily low-income individuals or those with disabilities, so autistic people on Medicaid may have fewer financial resources or more severe symptoms than those with private insurance. The researchers note that the life expectancy calculated in this study might underestimate the true average for the broader autistic population in the United States.
Another factor is demographics: autistic beneficiaries in the dataset were disproportionately children, young adults and males. While the models were adjusted for age and sex, there may be other unmeasured factors related to these demographics that influenced mortality.
Despite these caveats, the findings point to a clear need for improved long-term medical support for autistic individuals across their lifespans. Better preventative care for infectious diseases such as influenza, nutritional screenings and safety measures to prevent accidents could help narrow the life expectancy gap, the researchers argue.
Li concluded with a broad aim for the future: “Our long-term goal is to close the life expectancy gap facing autistic people by improving social support, home- and community-based services, and healthcare.”
The study, titled “Autism Spectrum Disorder and Life Expectancy Among Medicaid Beneficiaries,” was authored by Guohua Li, Carolyn G. DiGuiseppi, Ashley Blanchard, Matthew T. Russell, and Caleb Ing.
