LAUSR

Frequent emergency department (ED) users often have complex behavioral health and social needs. However, policy makers often focus on this population's medical system use without examining its use of behavioral health and social services systems. To illuminate the wide-ranging needs of frequent ED users, we compared medical, mental health, substance use, and social services use among nonelderly nonfrequent, frequent, and superfrequent ED users in San Francisco County, California. We linked administrative data for fiscal years 2013-15 for beneficiaries of the county's Medicaid managed care plan to a county-level integrated data system. Compared to nonfrequent users, frequent users were disproportionately female, white or African American/black, and homeless. They had more comorbidities and annual outpatient mental health visits (11.93 versus 4.16), psychiatric admissions (0.73 versus 0.07), and sobering center visits (0.17 versus <0.01), as well as disproportionate use of housing and jail health services. Our findings point to the need for shared knowledge across domains, at the patient and population levels. Integrated data can serve as a systems improvement tool and help identify patients who might benefit from coordinated care management. To deliver whole-person care, policy makers should prioritize improvements in data sharing and the development of integrated medical, behavioral, and social care systems.