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Long-term treatment retention of an emergency department initiated medication for opioid use disorder program

a b s t r a c t

Introduction: Medication for Opioid use disorder (MOUD) has been shown to decrease mortality, reduce over- doses, and increase treatment retention for patients with Opioid use disorder and has become the state- of-the-art treatment strategy in the emergency department (ED). There is little evidence on long-term (6 and 12 month) treatment retention outcomes for patients enrolled in MOUD from the ED.

Methods: A prospective observational study used a convenience sample of patients seen at one community hos- pital ED over 12 months. Patients >18 years with OUD were eligible for MOUD enrollment. After medical screen- ing, patients were evaluated by the addiction care coordinator (ACC) who evaluated and counselled the patient and if eligible, directly connected them with an addiction medicine appointment. Once enrolled, the patient re- ceived treatment with buprenorphine in the ED. A chart review was completed for all enrollments during the first year of the program. Treatment retention was determined by review of the prescription drug monitoring pro- gram and defined as patients receiving regular suboxone prescriptions at 6 and 12 months after index ED visit date.

Results: From June 2018 – May 2019 the ACCs evaluated patients during 691 visits, screening 571 unique patients. Of the 571 unique patients screened, 279 (48.9%) were enrolled into the MOUD program. 210 (75.3%) attended their first addiction medicine appointment, 151 (54.1%) were engaged in treatment at 1 month, 120 (43.0%) at 3 months, 105 (37.6%) at 6 months, and 97 (34.8%) at 12 months post index ED visit. Self-pay insurance status was associated with a significantly decrease in the odds of Long-term treatment retention.

Conclusion: Our ED-initiated MOUD program, in partnership with local addiction medicine services, produced high rates of long-term treatment retention.

(C) 2022

  1. Introduction

The opioid epidemic continues to inflict significant morbidity and mortality as it currently claims more than 180 lives per day in the United States, with deaths topping over 46,000 in 2018 [1-6]. The opioid epidemic was declared a national public health emergency in 2017, but a majority of patients with opioid use disorder (OUD) don’t have access to addiction medicine services [8].

For patients with OUD, the Emergency Department (ED) represents a critical access point for receiving medical care and thus, an important opportunity to reach OUD patients. Medication for Opioid Use Disorder (MOUD) has become the state-of-the-art Treatment modality for ED

* Corresponding author at: Summa Health, Department of Emergency Medicine, 525 E. Market Street, Akron, OH 44304, United States of America.

E-mail address: [email protected] (Q.R. Reuter).

management of OUD. MOUD has been shown to decrease mortality, re- duce overdoses, increase treatment retention, and decrease the costs as- sociated with addressing the opioid epidemic [9-15]. Led by an RCT published by D’Onofrio’s in 2015, further research has demonstrated EDs can be effectively utilized to provide initial buprenorphine induc- tions, resulting in short term treatment retention rates that are compa- rable to non-ED care settings [16-20].

D’Onofrio et al. followed-up their landmark trial with a report on the long-term treatment retention rates from their original trial, reporting roughly 50% long-term (6 and 12 months) treatment adherence, al- though this was no different than adherence rates within the control group [21]. Since this publication, there has been no further data pub- lished on long-term ED MOUD Treatment outcomes, and none from community hospital programs. Outside of emergency medicine, there a substantial body of evidence within the addiction medicine literature showing methadone, buprenorphine, and naloxone all produce better long-term treatment engagement that placebo. There is wide variation

https://doi.org/10.1016/j.ajem.2022.02.041

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of retention rates within the literature but a systemic review published by O’Connor et al. revealed rates of 56% and 45% at 6 and 12 months re- spectively [22,23]. This report aims to describe treatment retention rates for a community hospital ED MOUD program at 6 and 12 months.

  1. Methods
    1. Study design

This was a prospective observational study of ED patients enrolled in a MOUD program. As MOUD was viewed as standard of care, this study was reviewed and received an exemption from the Institutional Review Board (IRB).

    1. Study setting and population

Participants were enrolled over a twelve month period (June 2018 – May 2019) at one community hospital with over 33,000 annual ED visits. Patients >18 years old were eligible for enrollment if they had OUD and a clinical Opioid withdrawal score (COWS) of >=8 as measured by an ED nurse and verified by an emergency physician or advanced practice provider (APP). Patients were identified either by the treating clinician or via self-referral.

Patients were excluded if they were already established in a sub- stance use disorder (SUD) treatment program. Patients with low COWS scores were excluded to avoid inducing withdrawal but were en- couraged to return to ED in the next 12-24 h or when their symptoms worsened. Patients actively taking methadone based on their clinical presentation, COWS score, and Ohio Prescription Drug Monitoring Pro- gram (PDMP) report were also excluded and referred back to their treatment program. Pregnant patients were excluded and transferred to high-risk maternal fetal medicine for further management. Patients who presented with a significant medical issue requiring admission to the hospital were excluded. All patients that did not qualify for MOUD were still evaluated by the Addiction Care Coordinator (ACC) and pro- vided a referral to a clinically appropriate SUD treatment option. Data including patient demographics and COWS score were collected and documented in the medical record by the ACC during the ED visit.

    1. Study protocol

After the patient completed the medical screening exam, they were seen by the ACC, a nurse with specialized expertise in addiction medi- cine. The ACC nurses completed significant training via the American Society of Addition Medicine (ASAM) and had a strong working knowl- edge of local addiction medicine resources. The ACC completed a thor- ough interview with eligible patients and evaluated each criterion of the ASAM 6 dimension assessment [24]. The ASAM 6 dimension assess- ment evaluates a patient’s acute intoxication and/or withdrawal poten- tial, biomedical conditions, emotion/behavioral/cognitive conditions, readiness to change, relapse potential, and living environment to help identify the greatest barriers to recovery and formulate a treatment plan. Utilizing data collected via the ASAM 6 assessment, the ACC intro- duced the idea of the addiction recovery, then provided the patients with personalized feedback, attempted to enhance patient motivation, and finally negotiated and advised on a specific treatment plan. The ACC used motivational interviewing to help patients explore their un- derstanding, desire, and barriers to positive behavior change. If the pa- tient was eligible and desired MOUD treatment, the ACC directly linked the patient to an emergent outpatient addiction medicine ap- pointment. This follow-up included Office Based Opioid Treatment for buprenorphine management and an Intensive Outpatient Program for counseling. The ACC also ensured patient eligibility for addiction ser- vices, helped enroll patients on Medicaid when appropriate, arranged transportation if needed, and linked the patient to a peer recovery coach who contacted the patient that same day.

If a patient was enrolled in the MOUD program, treatment with bu- prenorphine was initiated during the index ED visit. Treatment consisted of buprenorphine/naloxone 8 mg/2 mg for one dose followed by two hours of observation. If their repeat COWS score at two hours was still >=8, the patient received a second dose of buprenorphine/nalox- one of either 4 mg/1 mg or 8 mg/2 mg depending on their repeat COWS score. If the patient’s Withdrawal symptoms were still not controlled, a third dose of 4 mg/1 mg or 8 mg/2 mg could be given at the discretion of the treating clinician. Once the patient’s withdrawal symptoms were controlled they were observed for approximately 1.5 h and discharged.

    1. Measures

Baseline patient demographics including age, gender, ethnicity, and medical and/or Psychiatric comorbidities at the time of MOUD induc- tion were collected via chart review. The ACC assessed and recorded the patient’s COWS, highest level of education, insurance status, em- ployment type, SUD type, Tobacco use, pregnancy status, marital status, financial and legal concerns, residence type, and spirituality at the index ED visit. These data elements were also extracted via chart review. Treatment retention was defined as patients receiving regular bupre- norphine prescriptions at 6 and 12 months from index ED visit date as assessed via the Ohio PDMP.

    1. Data analysis

The primary outcome of interest was treatment engagement at 6 and 12 months post index ED visit. Secondary outcomes included a de- scription of patient demographics, evaluation of factors associated with long-term treatment retention, and treatment retention at 1 and 3 months post index ED visit. Study data were imported into SPSSv25.0 software (IBM Corp., Armonk, NY) and summarized using frequencies and percentages. Generalized estimating equations, GEE, were con- structed to account for the covariance of repeated nominal measure- ments across the study time points with pairwise LSD testing performed to determine significantly distinct time milestones. Finally participants were stratified by those reaching the 12 month participa- tion milestone and summarized. A comparison between those reaching the 12 month milestone and those who did not was performed using a Student’s t-test for mean age comparison and Pearson chi-square tests for categorical comparisons. Bonferroni adjusted z tests were used to compare subcategories in the presence of overall significance. Addition- ally odds ratios with 95% confidence intervals were determined for sig- nificant (p < 0.05 via two-sided testing) categorical differences.

    1. Funding sources/disclosures

This project received funds from two grants, one from Ohio Depart- ment of Mental Health and Addiction services (OhioMHAS) and one from the United Way of Summit County (UWSC). Summa Health Sys- tem was the awardee of these funds, with our CEO, Dr. T. Clifford Deveny listed as the executive director and Jaimie McKinnon listed as the Prin- cipal Investigator. The Addiction Care Coordinator position was funded by the OhioMHAS and the UWSC funds. The UWSC also helped fund the peer recovery service coaches. These funding sources were also used to provide assistance with Patient transportation, sober housing, childcare during appointments, and a cellphone for patients to help manage appointments and transportation.

  1. Results

From June 2018 to May 2019 the ACCs evaluated patients during 691 visits, screening 571 unique patients. Of these patients, 279 were en- rolled in the MOUD program, 105 (37.6%, 95%CI, 31.8 to 43.4%; p <

0.001) were still enrolled at 6 months, and 97 (34.8%, 95%CI, 29.0 to

800

700

600

500

400

300

200

100

0

Total visits Unique Index Attended first Treatment Treatment Treatment Treatment 691 patients enrollments appointment engagement engagement engagement engagement

571 279 (48.9%) 210 (75.3%) 30 days 3 months 6 months 12 months

151 (54.1%) 120 (43.0%) 105 (37.6%) 97 (34.8%)

Engaged in treatment Not engaged in treatment

Fig. 1. Proportion of enrolled subjects from GEE Binary Response Model with 95% Confidence Intervals (Repeated Time Factor p < 0.001).

40.6%; p < 0.001) at 12 months post index ED visit (Fig. 1) Patients with self-pay insurance status were half as likely to be engaged in long-term OUD treatment as compared to those with Public insurance coverage (OR, 0.47; 95%CI, 0.23 to 0.94; p = 0.036). Patients with depression were more likely to be enrolled in treatment at 12 months than those without depression (OR, 1.70; 95%CI, 1.05 to 3.09; p = 0.032) (See

Tables 1 and 2).

  1. Discussion

Our work describes the long-term treatment retention of an ED- based MOUD program at a community hospital. Our intervention had several critical and unique components that produced the encouraging outcomes obtained. First, our Multidisciplinary team consisting of nurs- ing, social work, and physicians from addiction and emergency medi- cine specialties was vital to program inception and Ultimate success, especially with regards to the funding acquisition efforts that launched our initiative. We then worked to create strong relationships with com- munity addition medicine resources to help supplement our in-house addiction medicine resources. Continuous quality improvement efforts have also helped to identify areas for improvement such as utilizing travel resources for patients to help remove barriers to follow-up.

The ACC position was essential to the success of our program. They played a pivotal role in initiating patients on MOUD and navigated indi- viduals through the fragmented network of community addiction re- sources to ensure reliable follow-up. Their involvement negated any additional workload on physicians and APPs while simultaneously allowing for a thorough initial evaluation, building rapport with our pa- tients and gaining their trust. Finally, our program also benefited from strong local and regional grant support to fund the ACC position and we believe the expansion of support for similar positions will be vital to the growth and sustainability of other ED MOUD programs.

Despite the evidence base supporting buprenorphine, availability of MOUD treatment remains relatively limited [8]. The importance of low- barrier access to medical services is well documented. Insurance cover- age expansion increases access to preventative and primary care, chronic illness treatment, medications, and surgery. This expanded ac- cess and utilization in turn produces significant benefits to the health of patients [25]. Specific to OUD treatment, retention rates in countries with low barrier initiation and universal healthcare have shown above average levels of MOUD treatment retention [26]. Our finding that self-pay patients were less likely to remain in treatment, reiterates

this point and highlights the importance of insurance coverage in the success of OUD treatment. While seemingly intuitive, O’Connell et al. did not report on the role insurance status plays in OUD Treatment outcomes in their systematic review, making our findings particularly important to report [22].

Furthermore, the all-hours, low-barrier access of the ED is a unique and important factor contributing to the success of our program. The availability of ED resources as compared to traditional addiction medi- cine or Primary care settings, allows patients to enter treatment at a time when they are ready to begin recovery, rather than waiting for a distant appointment they may be unable to attend. Some may question whether the ED is an appropriate care setting for starting long term ag- onist therapy. Our data provides further supporting evidence that a community ED can not only can expand access, but also achieve mean- ingful long-term results.

Somewhat surprisingly, patients with a previous diagnosis of de- pression were more likely to remain in treatment than those without depression. No other psychiatric comorbidity, including anxiety, bipolar disorder, schizophrenia, and a history of previous suicide attempts, were associated either positively or negatively with treatment reten- tion. Previous literature has reported mixed results regarding the asso- ciation between psychiatric comorbidities and long-term treatment retention in OUD [22]. As such, it is difficult to draw definitive conclu- sions regarding the interplay between OUD treatment and psychiatric illness, but given the high level of Patient engagement needed for suc- cessful OUD treatment, addressing a patient’s depression, as well as other psychiatric comorbidities, is likely important in the overall health of this population.

This work is the second in the literature to report on long-term treat- ment retention of an ED-initiated MOUD program, and the first at a community hospital. Our retention rates are somewhat lower than those reported by O’Connor et al., but more data will be needed to defin- itively discern the comparative long-term treatment effectiveness of ED-initiated MOUD versus traditional addiction medicine care delivery models [22].

The ED is quickly developing into a ‘one stop shop’ for patients with SUD. Facilitated by the all-hour availability, and motivated by dedicated clinicians witnessing the devastating consequences of OUD, emergency medicine now is a leading force in combating the opioid epidemic. harm reduction through needle exchanges and safe injecting education are becoming more common in EDs. Emergency clinicians have led much of the research on safe opioid prescribing and minimalistic pain

Table 1 Patient demographics including gender, age, ethnicity, education, employment, insurance status and substance use disorder. N = 279.

Variable/statistic Enrolled Cohort

Table 2

Patient factors associated with 12 month treatment retention.

Variable/statistic Enrollment Status at 12 Months

P-value

Gender

(n = 279)

Not enrolled

Enrolled

Male 196 (70.3)

Female 83 (29.7)

Age (years)

Mean (SEM) 36.7 (0.66)

Range 18-67

<40 years 193 (69.2)

>=40 years 86 (30.8)

Race

Caucasian 253 (90.7)

Other 26 (9.3)

Education

Lower (High School/GED or less) 182 (65.2)

>Post high school education 97 (34.8) Employment

Not employed 191 (68.5)

Employed 88 (31.5)

Insurance status

Public 177 (63.4)

Private 48 (17.2)

Self-pay 54 (19.4)

Psychiatric comorbidities

Depression 76 (27.2)

Anxiety/PTSD 74 (26.5)

Bipolar 31 (11.1)

Schizophrenia 10 (3.6)

History of Suicide Attempt 5 (1.8)

Any Psych Comorbidity 116 (40.9)

No Psych Comorbidity 163 (59.1)

Social demographics

Married 42 (15.1)

Children 171 (61.3)

Legal Concerns 78 (28.0)

Financial Concerns 180 (64.5)

Undomiciled 46 (16.5)

Confidence in ability to quit

Less Confident 132 (47.3)

Extremely Confident (10/10) 147 (52.7)

Stage of change

Precontemplation/Contemplation/Unknown

74 (26.5)

Preparation/Action/Maintenance

205 (73.5)

Precontemplation

2 (0.7)

Contemplation

47 (16.8)

Preparation

99 (35.5)

Action

96 (34.4)

Maintenance

10 (3.6)

Unknown

25 (9.0)

management. To help prevent overdoses, EDs are more frequently pro- viding take-home naloxone. Finally, ED-initiated MOUD, through col- laboration with addiction medicine professionals, provides a unique pathway to recovery. All of these efforts work to reestablish trust be- tween OUD patients and the health care system and improve future chances of sobriety.

To better meet our patients, we have developed telemedicine ser- vices to maximize the expertise of our ACCs. Early results from this ef- fort are generally positive, and while our ACCs have only inducted a small number of patients via telemedicine, the extra support and treatment options have been well received by staff and patients alike. We also have conducted FoCUS groups with patients to identify barriers to care and best practices to cultivate. Initial results suggest that OUD patients are very willing to engage with telemedicine ser- vices to receive treatment and lower the barriers of traditional care delivery such as time and travel expenses. Furthermore we have de- veloped low cost advertising, i.e. waiting room signage and buttons for providers, encouraging patients to ask about MOUD services. A relatively large percentage (roughly 25%) of clinically appropriate pa- tients screened by the ACC continue to decline induction. Findings

(n = 182) (n = 97)

Gender 0.556

Male

130 (71.4)

66 (68.0)

Female Age (years)

Mean (SEM)

52 (28.6)

35.9 (0.79)

31 (32.0)

38.1 (1.19)

0.114

Race

0.087

Caucasian

169 (92.9)

84 (86.6)

Other

13 (7.1)

13 (13.4)

Education

Lower (High School/GED or less)

125 (68.7)

0.098

57 (58.8)

>Post high school education

57 (31.3)

40 (41.2)

Employment Not employed

125 (68.7)

0.913

66 (68.0)

Employed

57 (31.3)

31 (32.0)

Insurance status Public

106 (58.2)

0.036

71 (73.2)

Private

34 (18.7)

14 (14.4)

Self-pay

42 (23.1)

12 (12.4)

Psychiatric comorbidities

Depression

42 (23.1)

34 (35.1)

0.032

Anxiety/PTSD

50 (27.5)

24 (24.7)

0.623

Bipolar

22 (12.1)

9 (9.3)

0.477

Schizophrenia

9 (4.9)

1 (1.0)

0.173

History of Suicide Attempt

5 (2.7)

0

0.167

Social demographics

Married

26 (14.3)

16 (16.5)

0.623

Children

107 (58.8)

64 (66.0)

0.240

Legal Concerns

47 (25.8)

31 (32.0)

0.277

Financial Concerns

117 (64.3)

63 (64.9)

0.912

Homeless

34 (18.7)

12 (12.4)

0.175

onfidence in ability to quit

Extremely Confident (10/10) 90 (49.5) 57 (58.8) 0.138

C

Stage of change

0.178

Precontemplation/Contemplation/Unknown

53 (29.1)

21 (21.6)

Preparation/Action/Maintenance

129 (70.9)

76 (78.4)

ways to better engage and support this patient population is an ongo- ing effort.

Without question, our ACC team is the key element to the success of our program. While their extensive nursing experience and ASAM train- ing make them effective and valuable members of our team, other pro- grams can consider lower cost options such as substance use navigators to facilitate a MOUD program. The most basic yet critical element of the program is the ability to partner with and navigate our patients through emergent outpatient addiction medicine resources. Partnering with these outpatient clinics should be the first step of any new MOUD pro- gram.

There are various limitations to this observational study. Utilizing the PDMP is a limited means for assessing treatment adherence and simply signified a prescription has been filled, but offers no indication as to whether patients are actively taking the medication. Conversely, using the PDMP may have undercounted the number of patients still en- gaged in treatment as it may not reveal individuals receiving treatment from in-patient programs and day-programs. Finally, the ACCs were uniquely trained nursing staff and it may not be feasible for all hospitals to create ACC positions.

  1. Conclusion

Expanding MOUD availability via ED practices is a vital strategy to battling the opioid epidemic. Treatment retention rates at 6 and 12 months post index ED visit were encouraging and offer evidence that this strategy can have a lasting positive effect in the lives of OUD patients.

Prior presentations

None.

Author contributions

QR: study concept and design, acquisition of the data, analysis and interpretation of the data, drafting of the manuscript. ADS: drafting of the manuscript, critical revision of the manuscript for important intel- lectual content. JM: acquisition of the data, critical revision of the man- uscript for important intellectual content, acquisition of funding. DG: analysis and interpretation of the data, statistical expertise. NJ: study concept and design, critical revision of the manuscript for important in- tellectual content. DS: study concept and design, critical revision of the manuscript for important intellectual content, statistical expertise, and acquisition of funding.

Declaration of Competing Interest

QR, ADS, JM, DG, NJ, DS report no conflict of interest.

Acknowledgements

Jason Kolb, MD, Lindsay McKinnon, RN, Joseph Varley, MD, Suman Vellanki, MD, Ohio Department of Mental Health and Addiction Services (OhioMHAS) and United Way of Summit County (UWSC).

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