Substance Use, Homelessness, Mental Illness and Medicaid Coverage: A Set-up for High Emergency Department Utilization

Area of Science:

• Public Health
• Psychiatry
• Health Services Research

Background:

• Frequent users account for a significant portion of emergency department (ED) visits nationwide.
• Identifying characteristics of frequent ED users with psychiatric illness is crucial for targeted interventions.
• Understanding these patient profiles can optimize care delivery and reduce healthcare expenditures.

Purpose of the Study:

• To identify unique characteristics of frequent ED users seeking mental health care.
• To analyze demographic and clinical factors associated with frequent ED utilization for psychiatric conditions.
• To inform strategies for improving mental healthcare access and efficiency.

Main Methods:

• Retrospective analysis of adult ED visits for mental healthcare in California (2009-2014).
• Utilized patient-level data from the Office of Statewide Health Planning and Development.
• Defined frequent ED users as those with >4 visits in 12 months; analyzed associations with demographics, homelessness, and substance use disorders.

Main Results:

• Frequent users comprised 28.2% of mental healthcare ED visits.
• Co-occurring substance use disorders (77% vs. 37%) and homelessness (2.9% vs. 1.1%) were significantly associated with frequent ED use.
• Patients with Medicare or Medi-Cal (California's Medicaid) were more likely to be frequent users compared to those with private insurance.

Conclusions:

• Substance use disorders, homelessness, and public healthcare coverage are key factors linked to frequent ED use for mental illness.
• Addressing substance use and housing instability is vital for this patient population.
• These findings highlight the need for integrated care models to manage complex needs of frequent mental health ED users.