What drives frequent emergency department use in an integrated health system? National data from the Veterans Health Administration.

STUDY OBJECTIVE: There is widespread concern about patients with frequent emergency department (ED) use. We identify sociodemographic and clinical factors most strongly associated with frequent ED use within the Veterans Health Administration (VHA) nationally. METHODS: We conducted a cross-sectional analysis of national VHA databases (N=5,531,379) in 2010. The primary outcome measure was the number of VHA ED visits categorized into 6 frequency levels. RESULTS: In 2010, 4,600,667 (83.2%) VHA patients had no ED visit, whereas 493,391 (8.9%) had 1 visit, 356,258 (6.4%) had 2 to 4 visits, 70,741 (1.3%) had 5 to 10 visits, 9,705 (0.2%) had 11 to 25 visits, and 617 (0.01%) had greater than 25 visits. Increasing ED use frequency was associated with homelessness, medical diagnoses, substance abuse and psychiatric diagnoses, receipt of psychotropic and opioid prescriptions, and more frequent use of outpatient medical and mental health services. In multivariable analyses, factors most strongly associated with all levels of ED use were schizophrenia (odds ratio [OR] range 1.44 [95% confidence interval {CI} 1.41 to 1.47] to 6.86 [95% CI 5.55 to 8.48] across categories of increasing ED use), homelessness (OR range 1.41 [95% CI 1.38 to 1.43] to 6.60 [95% CI 5.36 to 8.12]), opioid prescriptions filled (OR range 2.09 [95% CI 2.07 to 2.10] to 5.08 [95% CI 4.16 to 6.19]), and heart failure (OR range 1.64 [95% CI 1.63 to 1.66] to 3.53 [95% CI 2.64 to 4.72]). CONCLUSION: Frequent ED use occurs even in a coordinated health care system that provides ready access to outpatient care. Frequent ED users are characterized by traits that represent high levels of psychosocial and medical needs. The correlates we identified for frequent ED use were consistent across multiple distinct levels of ED use.