National and Regional Trends in Mental Health Disorders Among U.S. Adults Treated in the State Mental Health System

Abstract This study examined the national and regional temporal trends of major mental health disorders, including attention-deficit/hyperactivity disorder (ADHD), anxiety, bipolar, depressive, and trauma- and stressor-related disorders, among U.S. adults treated in the State Mental Health System from 2013 to 2022. All ten rounds of Mental Health Client-Level Data (MH-CLD), covering 37,944,795 adults aged 18 and older, were analyzed. Unadjusted and adjusted logistic regression models, controlling for age, sex, and race/ethnicity, were used to assess trends over time. The analyses revealed a significant increasing national trend in service-seeking patients with anxiety disorders (AOR = 2.38, 95% CI 1.76–3.23), trauma- and stressor-related disorders (AOR = 1.56, 95% CI 1.21–1.95), and ADHD (AOR = 1.54, 95% CI 1.36–1.76) between 2013 and 2022. In contrast, bipolar disorders showed a significant decline, from 25.99% to 15.19% (AOR = 0.56, 95% CI 0.48–0.66). Depressive disorder remained the most common diagnosis, but did not exhibit a significant national trend. Regional trends were generally consistent with national patterns, with some exceptions, such as a significant decrease in depressive disorders in the West and more rapid increases in anxiety disorders in the Midwest and West compared with national trends. Evidence from a large, ten-year cohort of patients reveals national and regional shifts, as well as persistent patterns, in the prevalence of adults seeking services for major mental health disorders in the U.S. State Mental Health System. These findings highlight the importance of national policies and the need for targeted, region-specific mental health strategies.