Changes in Proportions of Emergency Department Patients With Mental Illness Noted in the National Hospital Ambulatory Medical Care Survey, 2012–2015

La Vonne A. Downey, PhD; Amanda Hong, MBA; Karina Herrera, BA


South Med J. 2020;113(2):51-54. 

In This Article

Abstract and Introduction


Objectives: The primary objective of this study was to determine whether there was a change in the rate and types of patients with psychiatric illnesses being seen in the emergency department (ED) from 2012 to 2015 using the National Ambulatory Care Survey. A secondary objective was to determine what if any changes occurred in the resources available to care for these patients.

Methods: Our study used 2012–2015 data from the National Hospital Ambulatory Medical Care Survey and the State Mental Health Agency Per Capita Mental Health Services Expenditures, and expenditures data from 2012–2015 to examine whether there was a significant change in the rate and type of mental illness ED visits. Additional data on the number of beds per region from the National Mental Health Services Survey, 2012–2015 were used. A t test was used to look for significant (P = 0.05) changes in the rate and types of patients, ED dispositions, ED reimbursement types, region and community level income, sex, age, state mental health funding, and psychiatric beds from 2012 to 2015.

Results: There was an 8% increase in the rate of patients who presented with a diagnosed mental health disorder (P = 0.03, 95% confidence interval [CI] 5.32–5.96) and substance use disorders (P = 0.03, 95% CI 0.564–0.122). The reimbursement for these visits did change (P = 0.01, 95% CI 0.245–0.685); however, there was no significant increase (P = 0.07, 95% CI−214 to 101) in state mental health budgets and the number of psychiatric and detox hospital beds from 2012 to 2015.

Conclusions: The rate and types of mental health patients coming to the ED are still on the rise. This is coupled with a lack of mental health infrastructure to address the needs and diagnoses that continue to be seen in the ED. States may need increased, targeted funding for mental health outside the increase in coverage via the Patient Protection and Affordable Care Act to slow the rate of mental health patients seen in the ED.


It is estimated that 1 in 5 adults in the United States—43.8 million, or 18.5%—experiences a mental disorder in a given year.[1–4] Of the 20.2 million adults in the United States who experienced a substance use disorder—10.2 million adults, or 50.5%—had a co-occurring mental illness.[5–8] The number of visits to emergency departments (EDs) has constantly grown, resulting in a 47% overall increase in the last 2 decades.[9,10] An increase in total numbers is not the only change EDs have undergone because there also have been changes in the type and complexity of illnesses and patients seen in the ED.[11,12]

One of the anticipated outcomes from the Patient Protection and Affordable Care Act (PPACA) was a possible reduction in the rate of patients with mental health–related (MH) ED visits. By expanding the numbers of those covered by health insurance, more people would be able to access less costly and more appropriate health care. The PPACA allowed millions to enroll in Medicaid, the single largest payer for MH care in the United States.[13–19] The PPACA also included provisions to promote the care coordination and integration of MH. One provision was the medical home, which specifically targets individuals with chronic physical and mental illness.[13,14] Providers who used this model of a patient-designated medical home were, under the PPACA, to be reimbursed by the state. It was thought that this new approach would affect those using the ED for their MH care. As such, the ED would experience a reduction in those who present with mental illnesses.

Patients with mental illnesses would have access and coverage for alternative community-based health care through the PPACA expansion; however, this is not what several researchers have found. Weiss et al note an increase of 55% for people with MH disorders and a 37% increase for people with substance abuse disorders presenting to the ED from 2006 to 2012.[20] These increases were seen in both males and females and occurred most often in EDs serving low-income communities. The Weiss et al findings were similar to an earlier study by Tang et al, who noted an increase for all of the patients in their study when examining trends in ED census from 1997 to 2007.[21] The increase also was seen in females in a range of ages from 18 to 64 years and in Hispanic or African American patients. Their study did not denote changes in diagnosis rates.[21]

Cummings et al showed that even with an expansion in Medicaid coverage under PPACA, the MH infrastructure to address the increased access to outpatient MH services is not in place.[22] They found that 34% of all counties in the United States do not have outpatient facilities that accept Medicaid to treat mental illnesses. In addition, in communities in which the larger share has Medicaid coverage, there was less access to outpatient MH facilities. They also found, with a few notable exceptions, that states have not significantly increased their state funding for mental health since 2011. This indicates one reason why Capp et al and Raven et al noted increases in patients with an MH diagnosis presenting to the ED since the implementation of the PPACA.[9–11] The ability to admit and treat patients in the ED is severely affected by the availability of psychiatric beds. According to reports by the National Alliance on Mental Illness and the Pew Charitable Trust, the United States has fewer than 37,679 psychiatric beds, which is a 13% reduction since 2010.[23,24]

The purpose of this study was to examine whether there has been a reduction or an increase in the rate and types of patients with psychiatric illnesses being seen in the ED from 2012 to 2015. It also examined what, if any, changes had occurred in the types of reimbursement for MH care in the ED and in the state-level MH infrastructure from 2012 to 2015.