Adults with intellectual and developmental disabilities, such as autism and Down syndrome, experience substantially higher rates of anxiety and depression than the general population of adults, researchers reported today in JAMA Network Open.  

The study, based on data from 44,000 adults, provides the first national estimates of mental health symptom prevalence, healthcare treatment and access barriers facing this population. 

“Our findings paint a distressing picture of the mental health and healthcare for people with these disabilities in the United States,” said senior author Dr. Dimitri Christakis, a professor of pediatrics at the University of Washington School of Medicine. “Historically, society has not taken the needs of this population as seriously as it should, so in that respect, our findings aren’t surprising. But the scale of burden is shocking.” 

The study used 2021-2023 data from the National Health Interview Survey, an annual, nationally representative survey conducted by the U.S. National Center for Health Statistics. From this data, 796 adults with likely intellectual and developmental disabilities were identified. They represent about 2.9 million Americans. 

The researchers examined their rates of diagnosed anxiety and depression, symptom frequency and severity, medication use, therapy engagement and cost-related barriers to care, adjusting for demographic and socioeconomic factors. Those data were contrasted with responses from 43,682 general-population adults. 

Among the key findings: 

Study-population adults were nine times more likely to report diagnosed anxiety (56.8% versus 10.6% %) and depression (56.9% versus 9.9%) than general-population adults. 
Daily symptom frequency was also markedly higher: 48.9% of study-population adults experienced daily anxiety (versus 7.7% among general-population peers), and 24.2% experienced daily depression (versus 1.3%). 
Only 40% of study-population adults reported receiving counseling or psychotherapy in the previous year, while 40% and 37% reported using psychiatric medication for anxiety and depression, respectively, in that span. These treatment patterns indicate an overreliance on medication instead of counseling, the authors said. 
Study-population adults were five times more likely than general-population peers to delay therapy due to cost (17.4% vs. 3.4%) and to forgo mental health care entirely because of expense (18.6% vs. 3.2%). This finding is notable, Christakis said, “given that many individuals with intellectual and developmental disabilities are covered by Medicaid.”  

“Having insurance doesn’t automatically translate to having access,” he noted. ”Our data suggest that, even with coverage, people with intellectual disabilities face significant out-of-pocket costs and difficulty finding providers who accept their insurance and have appropriate expertise in treating their symptoms.” 

 Collectively, the findings reveal national gaps in the ability of healthcare systems to effectively serve adults with intellectual and developmental disabilities, whose lifespans already are 10 to 20 years shorter, on average, than their general-population peers, Christakis noted. 

The study authors called for several actions, among them: 

Increased Medicaid reimbursement rates for mental health practitioners who serve individuals with intellectual and developmental disabilities. 
Integration of disability status into routine public health surveillance. 
Expansion of training programs in disability-informed mental health care. 
“Most of us are keenly aware of the mental health crisis confronting U.S. teenagers today. There is also one affecting people with intellectual and developmental disabilities,” Christakis said. 

The paper’s lead author is Anthony Osuna, a clinical psychologist and acting assistant professor of pediatrics at the UW School of Medicine.