Cluster Analysis of the Highest Users of Medical, Behavioral Health, and Social Services in San Francisco.

BACKGROUND: In the City and County of San Francisco, frequent users of emergent and urgent services across different settings (i.e., medical, mental health (MH), substance use disorder (SUD) services) are referred to as high users of multiple systems (HUMS). While often grouped together, frequent users of the health care system are likely a heterogenous population composed of subgroups with differential management needs. OBJECTIVE: To identify subgroups within this HUMS population using a cluster analysis. DESIGN: Cross-sectional study of HUMS patients for the 2019-2020 fiscal year using the Coordinated Care Management System (CCMS), San Francisco Department of Public Health's integrated data system. PARTICIPANTS: We calculated use scores based on nine types of urgent and emergent medical, MH, and SUD services and identified the top 5% of HUMS patients. Through k-medoids cluster analysis, we identified subgroups of HUMS patients. MAIN MEASURES: Subgroup-specific demographic, comorbidity, and service use profiles. KEY RESULTS: The top 5% of HUMS patients in the study period included 2657 individuals; 69.7% identified as men and 66.5% identified as non-White. We detected 5 subgroups: subgroup 1 (N = 298, 11.2%) who were relatively younger with prevalent MH and SUD comorbidities, and MH services use; subgroup 2 (N = 478, 18.0%), who were experiencing homelessness, with multiple comorbidities, and frequent use of medical services; subgroup 3 (N = 449, 16.9%), who disproportionately self-identified as Black, with prolonged homelessness, multiple comorbidities, and persistent HUMS status; subgroup 4 (N = 690, 26.0%), who were relatively older, disproportionately self-identified as Black, with prior homelessness, multiple comorbidities, and frequent use of medical services; and subgroup 5 (N=742, 27.9%), who disproportionately self-identified as Latinx, were housed, with medical comorbidities and frequent medical service use. CONCLUSIONS: Our study highlights the heterogeneity of HUMS patients. Interventions must be tailored to meet the needs of these diverse patient subgroups.

Extended-Release Naltrexone and Case Management for Treatment of Alcohol Use Disorder in the Emergency Department.

STUDY OBJECTIVE: To assess the feasibility of initiating treatment for alcohol use disorder with extended-release naltrexone and case management services in the emergency department (ED) and measure the intervention's impact on daily alcohol consumption and quality of life. METHODS: This is a 12-week prospective open-label single-arm study of a multimodal treatment for alcohol use disorder consisting of monthly extended-release naltrexone injections and case management services initiated at an urban academic ED. Participants were actively drinking adult patients in ED with known or suspected alcohol use disorder and an AUDIT-C score more than 4. The main feasibility outcomes included the rates of participant enrollment, retention in the study, and continuing treatment after study completion. Efficacy outcomes were the change in daily alcohol consumption (drinks per day; 14 g ethanol per drink), measured by a 14-day timeline followback, and the change in quality of life measured with a single-item Kemp quality of life scale. RESULTS: One hundred seventy-nine patients were approached, and 32 were enrolled (18%). Of the 32 enrolled patients, 25 (78%) completed all visits, and 22 (69%) continued naltrexone after the trial. The mean baseline daily alcohol consumption was 7.6 drinks per day (interquartile range, 4.5, 13.4), and the mean quality of life was 3.6 (SD 1.7) on a 7-point scale. The median daily alcohol consumption change was -7.5 drinks per day (Hodges-Lehmann 95% confidence interval -8.6, -5.9). The mean quality of life change was 1.2 points (95% confidence interval 0.5, 1.9; P<.01). CONCLUSION: We found that initiation of treatment of alcohol use disorder with extended-release naltrexone and case management is feasible in an ED setting and observed significant reductions in drinking with improved quality of life in the short term. Multicenter randomized controlled trials are needed to further validate these findings.

Advance Care Planning Among Patients With Advanced Illness Presenting to the Emergency Department.

BACKGROUND: Advance care planning (ACP) benefits emergency department (ED) patients with advanced illness. Although Medicare implemented physician reimbursement for ACP discussions in 2016, early studies found limited uptake. OBJECTIVE: We conducted a pilot study to assess ACP documentation and billing to inform the development of ED-based interventions to increase ACP. METHODS: We conducted a retrospective chart review to quantify the proportion of ED patients with advanced illness with Physician Orders for Life-Sustaining Treatment (POLST) or coding of ACP discussion in the medical record. We surveyed a subset of patients via phone to evaluate ACP participation. RESULTS: Of 186 patients included in the chart review, 68 (37%) had a POLST and none had ACP discussions billed. Of 50 patients surveyed, 18 (36%) recalled prior ACP discussions. CONCLUSIONS: Given the low uptake of ACP discussions in ED patients with advanced illness, the ED may be an underused setting for interventions to increase ACP discussions and documentation.

Violence and Emergency Department Use among Community-Recruited Women Who Experience Homelessness and Housing Instability.

Women who experience housing instability are at high risk for violence and have disproportionately high rates of emergency department (ED) use. However, little has been done to characterize the violence they experience, or to understand how it may be related to ED use. We recruited homeless and unstably housed women from San Francisco shelters, free meal programs, and single room occupancy (SRO) hotels. We used generalized estimating equations to examine associations between violence and any ED use (i.e., an ED visit for any stated reason) every 6 months for 3 years. Among 300 participants, 44% were African-American, and the mean age was 48 years. The prevalence of violence experienced in the prior 6 months included psychological violence (87%), physical violence without a weapon (48%), physical violence with a weapon (18%), and sexual violence (18%). While most participants (85%) who experienced physical violence with a weapon or sexual violence in the prior 6 months had not visited an ED, these were the only two violence types significantly associated with ED use when all violence types were included in the same model (ORphysical/weapon = 1.83, 95% CI 1.02-3.28; ORsexual = 2.15, 95% CI 1.30-3.53). Only violence perpetrated by someone who was not a primary intimate partner was significantly associated with ED use when violence was categorized by perpetrator. The need to reduce violence in this population is urgent. In the context of health care delivery, policies to facilitate trauma-informed ED care and strategies that increase access to non-ED care, such as street-based medicine, could have substantial impact on the health of women who experience homelessness and housing instability.

A National Study of Outpatient Health Care Providers' Effect on Emergency Department Visit Acuity and Likelihood of Hospitalization.

STUDY OBJECTIVE: Many policymakers believe that expanding access to outpatient care will reduce emergency department (ED) use. However, outpatient health care providers often refer their patients to EDs for evaluation and management. We examine the factors underlying outpatient provider referral, its effect on ED visit volume, and whether referred ED visits are more likely to result in hospitalization than self-referred visits. METHODS: We conducted a cross-sectional study of 19,342 adult (>18 years) respondents to the 2012 to 2014 National Health Interview Survey who reported they had visited an ED at least once in the past 12 months, representing an estimated 44,152,870 US adults. We categorized individuals as having been referred to the ED by an outside health care provider if they responded affirmatively to "your health care provider advised you to go" as a reason for their most recent ED visit. We performed descriptive analyses and logistic regressions to examine factors associated with outpatient health care provider referral to the ED. Respondents could choose multiple other reasons for their most recent ED visit, and we used existing Centers for Disease Control and Prevention guidelines to group these reasons into 2 categories: seriousness of the medical condition and lack of access to other providers. Our 2 main outcomes were whether an outpatient health care provider referred an individual to the ED and whether that ED visit resulted in hospitalization. RESULTS: Of the 44,152,870 US adults (18.58%; 95% confidence interval [CI] 18.21% to 18.95%) with one or more ED visits in the previous 12 months, 10,913,271 (24.72%; 95% CI 23.80% to 25.64%) were referred to the ED by an outpatient provider. Respondents who reported their ED visit was due to the seriousness of their medical condition were more likely to be referred to the ED (odds ratio [OR] 2.18; 95% CI 1.91 to 2.49), whereas those reporting a lack of access to other providers were less likely to be referred (OR 0.58; 95% CI 0.52 to 0.64). Visits referred to the ED were more likely to result in hospitalization than self-referrals (OR 2.07; 95% CI 1.87 to 2.31). CONCLUSION: Almost one quarter of individuals' most recent ED visits were driven by referrals from outpatient health care providers. Being referred to the ED by an outpatient provider is strongly associated with the seriousness of one's medical condition, which also increases the odds of hospitalization compared with ED discharge. After controlling for seriousness of medical condition, ED referral by an outpatient provider continues to have an independent association with hospitalization.

The Effectiveness of Emergency Department Visit Reduction Programs: A Systematic Review.

STUDY OBJECTIVE: Previous reviews of emergency department (ED) visit reduction programs have not required that studies meet a minimum quality level and have therefore included low-quality studies in forming conclusions about the benefits of these programs. We conduct a systematic review of ED visit reduction programs after judging the quality of the research. We aim to determine whether these programs are effective in reducing ED visits and whether they result in adverse events. METHODS: We identified studies of ED visit reduction programs conducted in the United States and targeted toward adult patients from January 1, 2003, to December 31, 2014. We evaluated study quality according to the Grading of Recommendations Assessment, Development, and Evaluation criteria and included moderate- to high-quality studies in our review. We categorized interventions according to whether they targeted high-risk or low-acuity populations. RESULTS: We evaluated the quality of 38 studies and found 13 to be of moderate or high quality. Within these 13 studies, only case management consistently reduced ED use. Studies of ED copayments had mixed results. We did not find evidence for any increase in adverse events (hospitalization rates or mortality) from the interventions in either high-risk or low-acuity populations. CONCLUSION: High-quality, peer-reviewed evidence about ED visit reduction programs is limited. For most program types, we were unable to draw definitive conclusions about effectiveness. Future ED visit reduction programs should be regarded as demonstrations in need of rigorous evaluation.

EMS-STARS: Emergency Medical Services "Superuser" Transport Associations: An Adult Retrospective Study.

Abstract Objective. Emergency medical services (EMS) "superusers" -those who use EMS services at extremely high rates -have not been well characterized. Recent interest in the small group of individuals who account for a disproportionate share of health-care expenditures has led to research on frequent users of emergency departments and other health services, but little research has been done regarding those who use EMS services. To inform policy and intervention implementation, we undertook a descriptive analysis of EMS superusers in a large urban community. In this paper we compare EMS superusers to low, moderate, and high users to characterize factors contributing to EMS use. We also estimate the financial impact of EMS superusers. Methods. We conducted a retrospective cross-sectional study based on 1 year of data from an urban EMS system. Data for all EMS encounters with patients age ≥18 years were extracted from electronic records generated on scene by paramedics. We identified demographic and clinical variables associated with levels of EMS use. EMS users were characterized by the annual number of EMS encounters: low (1), moderate (2-4), high (5-14), and superusers (≥15). In addition, we performed a financial analysis using San Francisco Fire Department (SFFD) 2009 charge and reimbursement data. Results. A total of 31,462 adults generated 43,559 EMS ambulance encounters, which resulted in 39,107 transports (a 90% transport rate). Encounters for general medical reasons were common among moderate and high users and less frequent among superusers and low users, while alcohol use was exponentially correlated with encounter frequency. Superusers were significantly younger than moderate EMS users, and more likely to be male. The superuser group created a significantly higher financial burden/person than any other group, comprising 0.3% of the study population, but over 6% of annual EMS charges and reimbursements. Conclusions. In this retrospective study, adult EMS "superusers" emerged as a distinct, predominantly male population and their EMS encounters were associated with alcohol use. Continued analysis of this unique, high-cost, and frequently transported population will likely illuminate specific intervention strategies.

Predicting cost of care using self-reported health status data.

BACKGROUND: We examined whether self-reported employee health status data can improve the performance of administrative data-based models for predicting future high health costs, and develop a predictive model for predicting new high cost individuals. METHODS: This retrospective cohort study used data from 8,917 Safeway employees self-insured by Safeway during 2008 and 2009. We created models using step-wise multivariable logistic regression starting with health services use data, then socio-demographic data, and finally adding the self-reported health status data to the model. RESULTS: Adding self-reported health data to the baseline model that included only administrative data (health services use and demographic variables; c-statistic = 0.63) increased the model" predictive power (c-statistic = 0.70). Risk factors associated with being a new high cost individual in 2009 were: 1) had one or more ED visits in 2008 (adjusted OR: 1.87, 95 % CI: 1.52, 2.30), 2) had one or more hospitalizations in 2008 (adjusted OR: 1.95, 95 % CI: 1.38, 2.77), 3) being female (adjusted OR: 1.34, 95 % CI: 1.16, 1.55), 4) increasing age (compared with age 18-35, adjusted OR for 36-49 years: 1.28; 95 % CI: 1.03, 1.60; adjusted OR for 50-64 years: 1.92, 95 % CI: 1.55, 2.39; adjusted OR for 65+ years: 3.75, 95 % CI: 2.67, 2.23), 5) the presence of self-reported depression (adjusted OR: 1.53, 95 % CI: 1.29, 1.81), 6) chronic pain (adjusted OR: 2.22, 95 % CI: 1.81, 2.72), 7) diabetes (adjusted OR: 1.73, 95 % CI: 1.35, 2.23), 8) high blood pressure (adjusted OR: 1.42, 95 % CI: 1.21, 1.67), and 9) above average BMI (adjusted OR: 1.20, 95 % CI: 1.04, 1.38). DISCUSSION: The comparison of the models between the full sample and the sample without theprevious high cost members indicated significant differences in the predictors. This has importantimplications for models using only the health service use (administrative data) given that the past high costis significantly correlated with future high cost and often drive the predictive models. CONCLUSIONS: Self-reported health data improved the ability of our model to identify individuals at risk for being high cost beyond what was possible with administrative data alone.

Incidence of Fit Test Failure During N95 Respirator Reuse and Extended Use.

Importance: The COVID-19 pandemic resulted in a widespread acute shortage of N95 respirators, prompting the Centers for Disease Control and Prevention to develop guidelines for extended use and limited reuse of N95s for health care workers (HCWs). While HCWs followed these guidelines to conserve N95s, evidence from clinical settings regarding the safety of reuse and extended use is limited. Objective: To measure the incidence of fit test failure during N95 reuse and compare the incidence between N95 types. Design, Setting, and Participants: This prospective cohort study, conducted from April 2, 2021, to July 15, 2022, at 6 US emergency departments (EDs), included HCWs who practiced N95 reuse for more than half of their clinical shift. Those who were unwilling to wear an N95 for most of their shift, repeatedly failed baseline fit testing, were pregnant, or had facial hair or jewelry that interfered with the N95 face seal were excluded. Exposures: Wearing the same N95 for more than half of each clinical shift and for up to 5 consecutive shifts. Participants chose an N95 model available at their institution; models were categorized into 3 types: dome (3M 1860R, 1860S, and 8210), trifold (3M 1870+ and 9205+), and duckbill (Halyard 46727, 46767, and 46827). Participants underwent 2 rounds of testing using a different mask of the same type for each round. Main Outcomes and Measures: The primary outcome was Occupational Safety and Health Administration-approved qualitative fit test failure. Trained coordinators conducted fit tests after clinical shifts and recorded pass or fail based on participants tasting a bitter solution. Results: A total of 412 HCWs and 824 N95s were fit tested at baseline; 21 N95s (2.5%) were withdrawn. Participants' median age was 34.5 years (IQR, 29.5-41.8 years); 252 (61.2%) were female, and 205 (49.8%) were physicians. The overall cumulative incidence of fit failure after 1 shift was 38.7% (95% CI, 35.4%-42.1%), which differed by N95 type: dome, 25.8% (95% CI, 21.2%-30.6%); duckbill, 28.3% (95% CI, 22.2%-34.7%); and trifold, 61.3% (95% CI, 55.3%-67.3%). The risk of fit failure was significantly higher for trifold than dome N95s (adjusted hazard ratio, 1.75; 95% CI, 1.46-2.10). Conclusions and Relevance: In this cohort study of ED HCWs practicing N95 reuse, fit failure occurred in 38.7% of masks after 1 shift. Trifold N95s had higher incidence of fit failure compared with dome N95s. These results may inform pandemic preparedness, specifically policies related to N95 selection and reuse practices.

2023 Society for Academic Emergency Medicine Consensus Conference on Precision Emergency Medicine: Development of a policy-relevant, patient-centered research agenda.

OBJECTIVES: Precision medicine is data-driven health care tailored to individual patients based on their unique attributes, including biologic profiles, disease expressions, local environments, and socioeconomic conditions. Emergency medicine (EM) has been peripheral to the precision medicine discourse, lacking both a unified definition of precision medicine and a clear research agenda. We convened a national consensus conference to build a shared mental model and develop a research agenda for precision EM. METHODS: We held a conference to (1) define precision EM, (2) develop an evidence-based research agenda, and (3) identify educational gaps for current and future EM clinicians. Nine preconference workgroups (biomedical ethics, data science, health professions education, health care delivery and access, informatics, omics, population health, sex and gender, and technology and digital tools), comprising 84 individuals, garnered expert opinion, reviewed relevant literature, engaged with patients, and developed key research questions. During the conference, each workgroup shared how they defined precision EM within their domain, presented relevant conceptual frameworks, and engaged a broad set of stakeholders to refine precision EM research questions using a multistage consensus-building process. RESULTS: A total of 217 individuals participated in this initiative, of whom 115 were conference-day attendees. Consensus-building activities yielded a definition of precision EM and key research questions that comprised a new 10-year precision EM research agenda. The consensus process revealed three themes: (1) preeminence of data, (2) interconnectedness of research questions across domains, and (3) promises and pitfalls of advances in health technology and data science/artificial intelligence. The Health Professions Education Workgroup identified educational gaps in precision EM and discussed a training roadmap for the specialty. CONCLUSIONS: A research agenda for precision EM, developed with extensive stakeholder input, recognizes the potential and challenges of precision EM. Comprehensive clinician training in this field is essential to advance EM in this domain.

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.

Comparison of presenting complaint vs discharge diagnosis for identifying " nonemergency" emergency department visits.

IMPORTANCE: Reduction in emergency department (ED) use is frequently viewed as a potential source for cost savings. One consideration has been to deny payment if the patient's diagnosis upon ED discharge appears to reflect a "nonemergency" condition. This approach does not incorporate other clinical factors such as chief complaint that may inform necessity for ED care. OBJECTIVE: To determine whether ED presenting complaint and ED discharge diagnosis correspond sufficiently to support use of discharge diagnosis as the basis for policies discouraging ED use. DESIGN, SETTING, AND PARTICIPANTS: The New York University emergency department algorithm has been commonly used to identify nonemergency ED visits. We applied the algorithm to publicly available ED visit data from the 2009 National Hospital Ambulatory Medical Care Survey (NHAMCS) for the purpose of identifying all "primary care-treatable" visits. The 2009 NHAMCS data set contains 34,942 records, each representing a unique ED visit. For each visit with a discharge diagnosis classified as primary care treatable, we identified the chief complaint. To determine whether these chief complaints correspond to nonemergency ED visits, we then examined all ED visits with this same group of chief complaints to ascertain the ED course, final disposition, and discharge diagnoses. MAIN OUTCOMES AND MEASURES: Patient demographics, clinical characteristics, and disposition associated with chief complaints related to nonemergency ED visits. RESULTS: Although only 6.3% (95% CI, 5.8%-6.7%) of visits were determined to have primary care-treatable diagnoses based on discharge diagnosis and our modification of the algorithm, the chief complaints reported for these ED visits with primary care-treatable ED discharge diagnoses were the same chief complaints reported for 88.7% (95% CI, 88.1%-89.4%) of all ED visits. Of these visits, 11.1% (95% CI, 9.3%-13.0%) were identified at ED triage as needing immediate or emergency care; 12.5% (95% CI, 11.8%-14.3%) required hospital admission; and 3.4% (95% CI, 2.5%-4.3%) of admitted patients went directly from the ED to the operating room. CONCLUSIONS AND RELEVANCE: Among ED visits with the same presenting complaint as those ultimately given a primary care-treatable diagnosis based on ED discharge diagnosis, a substantial proportion required immediate emergency care or hospital admission. The limited concordance between presenting complaints and ED discharge diagnoses suggests that these discharge diagnoses are unable to accurately identify nonemergency ED visits.

Hospital variability in adoption of alcohol and drug screening in adult trauma patients.

BACKGROUND: Despite recommendations to screen all injured patients for substance use, single-center studies have reported underscreening. This study sought to determine if there was significant practice variability in adoption of alcohol and drug screening of injured patients among hospitals participating in the Trauma Quality Improvement Program. METHODS: This was a retrospective observational cross-sectional study of trauma patients 18 years or older in Trauma Quality Improvement Program 2017-2018. Hierarchical multivariable logistic regression modeled the odds of screening for alcohol and drugs via blood/urine test while controlling for patient and hospital variables. We identified statistically significant high and low-screening hospitals based on hospitals' estimated random intercepts and associated confidence intervals (CIs). RESULTS: Of 1,282,111 patients at 744 hospitals, 619,423 (48.3%) were screened for alcohol, and 388,732 (30.3%) were screened for drugs. Hospital-level alcohol screening rates ranged from 0.8% to 99.7%, with a mean rate of 42.4% (SD, 25.1%). Hospital-level drug screening rates ranged from 0.2% to 99.9% (mean, 27.1%; SD, 20.2%). A total of 37.1% (95% CI, 34.7-39.6%) of variance in alcohol screening and 31.5% (95% CI, 29.2-33.9%) of variance in drug screening were at the hospital level. Level I/II trauma centers had higher adjusted odds of alcohol screening (adjusted odds ratio [aOR], 1.31; 95% CI, 1.22-1.41) and drug screening (aOR, 1.16; 95% CI, 1.08-1.25) than Level III and nontrauma centers. We found 297 low-screening and 307 high-screening hospitals in alcohol after adjusting for patient and hospital variables. There were 298 low-screening and 298 high-screening hospitals for drugs. CONCLUSION: Overall rates of recommended alcohol and drug screening of injured patients were low and varied significantly between hospitals. These results underscore an important opportunity to improve the care of injured patients and reduce rates of substance use and trauma recidivism. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.

Understanding the association between frequent emergency department use and jail incarceration: A cross-sectional analysis.

BACKGROUND: Frequent emergency department (ED) use and incarceration can be driven by underlying structural factors and social needs. If frequent ED users are at increased risk for incarceration, ED-based interventions could be developed to mitigate this risk. The objective of this study was to determine whether frequent ED use is associated with incarceration. METHODS: We conducted a retrospective cross-sectional study of 46,752 individuals in San Francisco Department of Public Health's interagency, integrated Coordinated Care Management System (CCMS) during fiscal year 2018-2019. The primary exposure was frequency of ED visits, and the primary outcome was presence of any county jail incarceration during the study period. We performed descriptive and multivariable analysis to determine the association between the frequency of ED use and jail encounters. RESULTS: The percentage of those with at least one episode of incarceration during the study period increased with increasing ED visit frequency. Unadjusted odds of incarceration increased with ED use frequency: odds ratio (OR) = 2.14 (95% confidence interval [CI] = 1.94-2.35) for infrequent use, OR = 4.98 (95% CI = 4.43-5.60) for those with frequent ED use, and OR = 12.33 (95% CI = 9.59-15.86) for those with super-frequent ED use. After adjustment for observable confounders, the odds of incarceration for those with super-frequent ED use remained elevated at 2.57 (95% CI = 1.94-3.41). Of those with super-frequent ED use and at least one jail encounter, 18% were seen in an ED within 30 days after release from jail and 25% were seen in an ED within 30 days prior to arrest. CONCLUSIONS: Frequent ED use is independently associated with incarceration. The ED may be a site for intervention to prevent incarceration among frequent ED users by addressing unmet social needs.