Mental Health Gaps in Intellectual Disability: What a National Study Found
Quantifying a Gap the Field Long Suspected
Mental health disparities in adults with intellectual and developmental disabilities have been described qualitatively in clinical literature for years. What has been missing is rigorous, nationally representative quantification -- the kind of data needed to drive policy responses, funding allocations, and public health monitoring. A study published in JAMA Network Open provides that foundation for the United States.
The research used data from the 2021-2023 National Health Interview Survey, a continuous survey conducted by the U.S. National Center for Health Statistics and one of the most methodologically rigorous sources of population health data in the country. From 44,000 adult respondents, the authors identified 796 adults likely to have intellectual and developmental disabilities -- representing roughly 2.9 million Americans after statistical weighting. These individuals were compared against 43,682 adults without functional impairments across a broad range of mental health measures.
Key Findings
Adults with intellectual and developmental disabilities reported diagnosed anxiety at a rate of 56.8%, compared to 10.6% in the general adult population -- a roughly ninefold difference. Diagnosed depression showed a near-identical disparity: 56.9% versus 9.9%. Daily anxiety symptoms were reported by 48.9% of the study population versus 7.7% of controls; daily depression by 24.2% versus 1.3%.
These numbers reflect a population living with conditions that, in many cases, are diagnosable and treatable -- but are not being adequately treated. Treatment data showed that 40% of study-population adults reported using psychiatric medication for anxiety and 37% for depression, while only 40% accessed counseling or psychotherapy in the prior year. The authors characterize the balance as overreliance on pharmacological management at the expense of behavioral intervention, for which evidence is strong.
Access Barriers Despite Insurance Coverage
Cost-driven barriers to care were five times more prevalent in the study population than in the general population. Adults with intellectual and developmental disabilities were 5.1 times more likely to delay therapy because of expense (17.4% versus 3.4%) and 5.8 times more likely to forgo care entirely due to cost (18.6% versus 3.2%). Many individuals in this population are Medicaid beneficiaries -- suggesting that the barriers are not primarily insurance-related but reflect low provider availability, inadequate reimbursement for disability-specialized services, and the absence of providers trained to deliver care adapted for this population.
Adults with intellectual and developmental disabilities already live 10 to 20 years fewer than the general population average. The mental health burden documented here adds another dimension to that shortened life expectancy.
Policy Implications and Study Limitations
The authors call for policy action on three fronts: higher Medicaid reimbursement rates for practitioners serving this population, integration of disability status into standard public health surveillance, and expanded training in disability-informed mental health care. Limitations include the cross-sectional design, which prevents causal inference, and the use of a survey-based disability identification method, which may misclassify some individuals. The 796 study-population adults limit the power of subgroup analyses. The study was funded by Special Olympics through grants from the CDC and other organizations. Corresponding author: Dimitri Christakis, MD, MPH, dchristakis@specialolympics.org.