Analysis of Drugs in Saliva of US Military Veterans Treated for Substance Use Disorders Using Supported Liquid Extraction and Surface-Enhanced Raman Spectral Analysis.

According to the Center for Disease Control, there were more than 107,000 US drug overdose deaths in 2021, over 80,000 of which due to opioids. One of the more vulnerable populations is US military veterans. Nearly 250,000 military veterans suffer from substance-related disorders (SRD). For those seeking treatment, buprenorphine is prescribed to help treat opioid use disorder (OUD). Urinalysis is currently used to monitor buprenorphine adherence as well as to detect illicit drug use during treatment. Sometimes sample tampering occurs if patients seek to generate a false positive buprenorphine urine test or mask illicit drugs, both of which can compromise treatment. To address this problem, we have been developing a point-of-care (POC) analyzer that can rapidly measure both medications used for treatment and illicit drugs in patient saliva, ideally in the physi-cian's office. The two-step analyzer employs (1) supported liquid extraction (SLE) to isolate the drugs from the saliva and (2) surface-enhanced Raman spectroscopy (SERS) to detect the drugs. A prototype SLE-SERS-POC analyzer was used to quantify buprenorphine at ng/mL concentrations and identify illicit drugs in less than 1 mL of saliva collected from 20 SRD veterans in less than 20 min. It correctly detected buprenorphine in 19 of 20 samples (18 true positives, 1 true negative and 1 false negative). It also identified 10 other drugs in patient samples: acetaminophen, amphetamine, cannabidiol, cocaethylene, codeine, ibuprofen, methamphetamine, methadone, nicotine, and norbuprenorphine. The prototype analyzer shows evidence of accuracy in measuring treatment medications and relapse to drug use. Further study and development of the system is warranted.

Social ecological factors and medication treatment for opioid use disorder among justice-involved rural and urban persons: the Geographic variation in Addiction Treatment Experiences (GATE) longitudinal cohort study protocol.

INTRODUCTION: Three medications are Food and Drug Administration approved for the treatment of opioid use disorder (OUD); however, these medications are underused within prisons, which elevates the risk of relapse and overdose when persons with opioid use disorder (POUD) are released. Research is scant regarding the multilevel factors associated with POUDs' willingness to initiate medication treatment for opioid use disorder (MOUD) while in prison and their continued engagement in treatment after release. Furthermore, rural and urban populations have not been compared. The Geographic variation in Addiction Treatment Experiences (GATE) study seeks to identify multilevel factors (ie, individual, personal network, and structural factors) influencing prison-based extended-release injectable naltrexone (XR-NTX) and buprenorphine initiation and will examine predictors of postrelease MOUD use and adverse outcomes (ie, relapse, overdose, recidivism) among both rural and urban POUDs. METHODS AND ANALYSIS: This mixed methods study employs a social ecological framework. A prospective observational longitudinal cohort study is being conducted with 450 POUDs using survey and social network data collected in prison, immediately postrelease, 6 months postrelease and 12 months postrelease to identify multilevel rural-urban variation in key outcomes. In-depth qualitative interviews are being conducted with POUDs, prison-based treatment staff and social service clinicians. To maximise rigour and reproducibility, we employ a concurrent triangulation strategy, whereby qualitative and quantitative data contribute equally to the analysis and are used for cross-validation when examining scientific aims. ETHICS AND DISSEMINATION: The GATE study was reviewed and approved by the University of Kentucky's Institutional Review Board prior to implementation. Findings will be disseminated through presentations at scientific and professional association conferences, peer-reviewed journal publications and a summary aggregate report submitted to the Kentucky Department of Corrections.

Patients' perceptions of self-administered dosing to opioid agonist treatment and other changes during the COVID-19 pandemic: a qualitative study.

OBJECTIVES: During the COVID-19 pandemic, addiction treatment services received official guidance asking them to limit face-to-face contact with patients and to prescribe opioid agonist treatment (OAT) medication flexibly. With the aim for most patients to receive take-home supplies for self-administration rather than attendance for observed daily dosing. DESIGN: This was a theory-driven, clinically applied qualitative study, with data for thematic analysis collected by semi-structured, audio-recorded, telephone interviews. PARTICIPANTS: Twenty-seven adults (aged ≥18 years) enrolled in sublingual (tablet) buprenorphine and oral (liquid) methadone OAT. SETTING: Community addictions centre in the London Borough of Lambeth operated by South London and Maudsley NHS Trust. RESULTS: Three major themes were identified: (1) dissatisfaction and perceived stigma with OAT medication dispensing arrangements before the pandemic; (2) positive adaptations in response to COVID-19 by services; (3) participants recommended that, according to preference and evidence of adherence, OAT should be personalised to offer increasing medication supplies for self-administration from as early as 7 days after commencement of maintenance prescribing. CONCLUSIONS: In an applied qualitative study of patients enrolled in OAT during the COVID-19 pandemic, participants endorsed their opportunity to take medication themselves at home and with virtual addiction support. Most patients described a preference for self-administration with increased dispensing supplies, from as early as 7 days into maintenance treatment, if they could demonstrate adherence to their prescription.

Efficacy and Safety of Buprenorphine in a Single-Shot Peripheral Nerve Block: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

The purpose of this study was to evaluate the safety and efficacy of buprenorphine compared with placebo in prolonging the duration of analgesia in single-injection peripheral nerve block. The systematic review and meta-analysis were conducted following the PRISMA statement and Review Manager was used for meta-analysis. Outcomes were calculated using the mean difference (MD) with 95% confidence interval (CI) for continuous data. For dichotomous outcomes, effect sizes were estimated by calculating pooled risk ratio (RR) with 95% CI. Statistical heterogeneity was estimated by the I2 statistic. Compared with placebo, buprenorphine prolonged the duration of analgesia by an average of 8 hours (MD, 8.01; 95% CI, 6.79 to 9.24; P < .00001). The cumulative pain scores within 24 hours (MD, -0.8; 95% CI, -1.21 to -0.40; P < .0001) and the 24-hour opioid consumption (MD, -5.56; 95% CI, -10.60 to -0.52; P = .03) after surgery was lower with buprenorphine group. Conversely, buprenorphine increased the incidence of postoperative nausea and vomiting (PONV) (RR, 1.67; 95% CI, 1.16 to 2.39; P = .006). Buprenorphine is effective in prolonging analgesia, decreasing pain scores and opioid consumption, however, it increases the risk of PONV.

Building a statewide network of MOUD expertise using tiered ECHO® mentoring opportunities.

BACKGROUND: Expanding access to workforce training for opioid use disorder (OUD) treatment continues to be a priority. This study explored the use of tiered mentoring opportunities within an ECHO® model to expand treatment capacity and develop a statewide network of medications for OUD (MOUD) expertise. ECHO® engages participants in a virtual community to learn best practices through case-based learning and interactions with experts. METHODS: We studied two incentivized Illinois MOUD ECHO® training programs by examining aggregate demographic and prescribing data across eight training cohorts (n = 199 participants). Participants (n = 51) in the last two cohorts were evaluated with expanded pre- and post-training surveys. Qualitative interviews were completed with a subset (n = 13) to examine effects observed in the survey data. RESULTS: For the whole group, we found a geographic expansion of the participants' prescribing capacity that reached into rural and other underserved areas in Illinois. Participants in the last two cohorts reported both increased self-efficacy for OUD treatment and increased connectedness to the addiction treatment community in Illinois. Participants who progressed through the tiered mentorship roles were found to exhibit stepwise increases in reported self-efficacy and connectedness measures. CONCLUSION: An incentivized ECHO® program yielded substantive outcomes in terms of increased prescribing capacity across the state. The use of tiered mentoring opportunities enabled participants to develop MOUD expertise and support novice providers in a growing statewide network. There is potential to train professionals to a high level of expertise when the ECHO® model is combined with a mentorship pathway.

Evaluation and guide for embedding opioid use disorder education in health professions' curricula.

BACKGROUND: Morbidity and mortality from Opioid Use Disorder is a health crisis in the United States. During the COVID-19 pandemic, there was a devastating increase of 38.4% in overdose deaths from the 12-month period leading up to June 2019 compared with the 12-month period leading up to May 2020, primarily driven by synthetic opioids. Buprenorphine is an effective medication for opioid use disorder but uptake is slow due in part to lack of provider knowledge, confidence, and negative attitudes/stigma toward patients with OUD. Addressing these barriers in academic training is a promising approach to building workforce able to effectively treat opioid use disorder. METHODS: Our university developed a training for pre-licensure physicians, physician assistants and psychiatric nurse practitioners that included the DATA Waiver training and a shadowing experience. Expected outcomes included improved knowledge, skills and attitudes about persons with OUD and buprenorphine treatment, plans to provide this treatment post-graduation, for pre-licensure learners to have completed all requirements to prescribe buprenorphine post-graduation, and for the training to be embedded into school's curricula. RESULTS: Results were positive overall including improved knowledge and attitudes toward persons with OUD, better understanding of the benefits of this treatment for patients, increased confidence and motivation to provide this treatment post-graduation. The training is now embedded in each program's graduation requirements. CONCLUSION: Developing a didactic and experiential training on buprenorphine treatment for opioid use disorder and embedding it into medical, physician assistant, and psychiatric nurse practitioner licensure programs can help prepare future providers to treat opioid use disorder in a range of settings. Key to replicating this program in other university settings is to engage faculty members who actively provide treatment to persons with OUD to ensure shadowing opportunities and serve as role models for learners.

Buprenorphine Program Evaluation in a Private Psychiatric Office-Based Practice.

PURPOSE: The opioid crisis has contributed to the mortality, morbidity, and rising healthcare costs in the United States. Buprenorphine (BUP) is an effective medication for opioid use disorder. The aims of this quality assurance evaluation of a BUP program were to (a) evaluate the clinic's performance in illicit opioid abstinence and (b) identify patient risk and resilience characteristics to improve patient success in recovery with BUP. METHODS: A retrospective chart review of open (n = 35) and closed (n = 21) cases and a cross-sectional survey in open cases were completed. Adults (aged ≥18 years) who completed 6 months of BUP treatment at a psychiatric clinic were included. Clinical performance was measured with percentages of opioid-negative urine and completed monthly urine drug tests (UDTs) for the first 6 months. Open cases were surveyed regarding risk and resilience characteristics (frequency of opioid cravings and triggers, therapy participation, and coping skills). Descriptive statistics, t test, and chi-square test were used to analyze data. RESULTS: Average opioid-negative urine was significantly higher in open cases than closed cases (88.57% vs. 74.82%; t = 2.885, p = .004). There was no significant association between open cases (61.4%) and closed cases (73.8%) in completed monthly UDT. Opening and closing of cases stabilized with mandatory monthly UDT. Most individuals reported therapy participation, minimal opioid cravings, and use of distraction to cope with chronic-pain-induced cravings. CONCLUSIONS/IMPLICATIONS: This clinic met benchmarks leading to improved substance recovery. Recommendations include regular evaluations of UDT, cravings, and chronic pain; therapy participation; and continuous quality assurance activities.

A buprenorphine depot formulation provides effective sustained post-surgical analgesia for 72 h in mouse femoral fracture models.

Adequate pain management is essential for ethical and scientific reasons in animal experiments and should completely cover the period of expected pain without the need for frequent re-application. However, current depot formulations of Buprenorphine are only available in the USA and have limited duration of action. Recently, a new microparticulate Buprenorphine formulation (BUP-Depot) for sustained release has been developed as a potential future alternative to standard formulations available in Europe. Pharmacokinetics indicate a possible effectiveness for about 72 h. Here, we investigated whether the administration of the BUP-Depot ensures continuous and sufficient analgesia in two mouse fracture models (femoral osteotomy) and could, therefore, serve as a potent alternative to the application of Tramadol via the drinking water. Both protocols were examined for analgesic effectiveness, side effects on experimental readout, and effects on fracture healing outcomes in male and female C57BL/6N mice. The BUP-Depot provided effective analgesia for 72 h, comparable to the effectiveness of Tramadol in the drinking water. Fracture healing outcome was not different between analgesic regimes. The availability of a Buprenorphine depot formulation for rodents in Europe would be a beneficial addition for extended pain relief in mice, thereby increasing animal welfare.

Adaptation of the Tele-Harm Reduction intervention to promote initiation and retention in buprenorphine treatment among people who inject drugs: a retrospective cohort study.

Background: At the start of the pandemic, relaxation of buprenorphine prescribing regulations created an opportunity to create new models of medications for opioid use disorder (MOUD) delivery and care. To expand and improve access to MOUD, we adapted and implemented the Tele-Harm Reduction (THR) intervention; a multicomponent, telehealth-based and peer-driven intervention to promote HIV viral suppression among people who inject drugs (PWID) accessing a syringe services program (SSP). This study examined buprenorphine initiation and retention among PWID with opioid use disorder who received the adapted THR intervention at the IDEA Miami SSP.Methods: A retrospective chart review of participants who received the THR intervention for MOUD was performed to examine the impact of telehealth on buprenorphine retention. Our primary outcome was three-month retention, defined as three consecutive months of buprenorphine dispensed from the pharmacy.Results: A total of 109 participants received the adapted THR intervention. Three-month retention rate on buprenorphine was 58.7%. Seeing a provider via telehealth at baseline or any follow up visit (aOR = 7.53, 95% CI: [2.36, 23.98]) and participants who had received an escalating dose of buprenorphine after baseline visit (aOR = 8.09, 95% CI: [1.83, 35.87]) had a higher adjusted odds of retention at three months. Participants who self-reported or tested positive for a stimulant (methamphetamine, amphetamine, or cocaine) at baseline had a lower adjusted odds of retention on buprenorphine at three months (aOR = 0.29, 95% CI: [0.09, 0.93]).Conclusions: Harm reduction settings can adapt dynamically to the needs of PWID in provision of critical lifesaving buprenorphine in a truly destigmatising approach. Our pilot suggests that an SSP may be an acceptable and feasible venue for delivery of THR to increase uptake of buprenorphine by PWID and promote retention in care.KEY MESSAGESThe Tele-Harm Reduction intervention can be adapted for initiating and retaining people who inject drugs with opioid use disorder on buprenorphine within a syringe services program settingUsing telehealth was associated with increased three-month buprenorphine retentionBaseline stimulant use was negatively associated with three-month buprenorphine retention.

Expanding buprenorphine in U.S. jails: One county's response to addressing the fears of diversion.

INTRODUCTION: The overdose crisis continues to be a major public health emergency in the United States. While effective medications for opioid use disorder (MOUD), such as buprenorphine, have ample scientific evidence to their effectiveness, they are underutilized in the United States and particularly in criminal justice settings. One rationale against the expansion of MOUD in carceral settings cited by jail, prison, and even Drug Enforcement Administration leaders is the potential for diversion of these medications. However, currently little data exist to support this claim. Instead, successful examples from early expansion states could help to change attitudes and calm misconceptions around diversion fears. RESULTS: In this commentary, we discuss the experience of one county jail that successfully expanded buprenorphine treatment and did not suffer significant impacts related to diversion. Instead, the jail found that their holistic and compassionate approach to buprenorphine treatment improved conditions both for incarcerated individuals and jail staff. CONCLUSION: Amid a changing policy landscape and a federal commitment to increase access to effective treatments in criminal justice settings, lessons can be learned from jails and prisons that have already or are working toward expansion of MOUD in their facilities. Ideally, these anecdotal examples, in addition to data, will help to encourage more facilities to incorporate buprenorphine into their opioid use disorder treatment strategies.

High-Dose Buprenorphine Initiation in the Emergency Department Among Patients Using Fentanyl and Other Opioids.

This cohort study examines buprenorphine treatment initiation, response, and follow-up among patients presenting to California emergency departments (EDs) who reported fentanyl or other opioid use.

Community-, network-, and individual-level predictors of uptake of medication for opioid use disorder among young people who inject drugs and their networks: A multilevel analysis.

BACKGROUND: Opioid use has been increasing at alarming rates over the past 15 years, yet uptake of medication for opioid use disorder (MOUD) remains low. Much of the research on individual characteristics predicting MOUD uptake is equivocal, and there is a dearth of research on setting-level and network-level characteristics that predict MOUD uptake. Towards a more holistic, multilevel understanding, we explore individual-level, network-level, and community-level characteristics associated with MOUD uptake. METHODS: Baseline data from a longitudinal study of young people who inject drugs and their injection and support network members living in Chicago (N = 165) was used to conduct cross-sectional multilevel logistic regression analyses to examine associations between MOUD uptake and a set of potential predictors at the individual-, network-, and community-levels that were chosen based on theoretical relevance or support from previous empirical studies. RESULTS: Stigma at both the individual and community levels was significantly associated with MOUD uptake (though in different directions). Greater individual-level stigma was associated with a higher likelihood of MOUD uptake, while having a more normatively stigmatizing community environment was associated with a lower likelihood of MOUD uptake. Using heroin and cocaine simultaneously and having a larger support network were associated with a greater likelihood of MOUD uptake. CONCLUSIONS: The present study's holistic, multilevel approach identified three individual-level characteristics, one network-level characteristic, and one community-level characteristic associated with MOUD uptake. However, more research is needed examining multilevel predictors, to help with developing interventions addressing barriers to MOUD use at multiple levels of influence.

Treatment Experiences for Patients Receiving Buprenorphine/Naloxone for Opioid Use Disorder: A Qualitative Study of Patients' Perceptions and Attitudes.

Background: Although buprenorphine/naloxone has been demonstrated to be an effective treatment for patients with opioid use disorder (OUD), treatment retention has been a challenge. This study extends what is presently a limited literature regarding patients' experiences with this medication and the implications for treatment retention. Methods: The study was conducted as a qualitative investigation of patients in treatment for OUD at the time of the study. Forty-three patients (27 men, 15 women, mean age 34.7) were recruited from three clinical settings, a community health center, an academically-based treatment site, and an independent substance abuse treatment facility. Most patients had returned to use in the past after attempts to become abstinent. Results: Patients generally reported positive experiences with this medication noting it helped to reduce opioid cravings quickly. As important considerations for treatment retention, patients emphasized a firm commitment to achieving abstinence when beginning treatment and a prescriber who is informed about and attentive to their emotional state. Diverging attitudes did exist regarding treatment duration as some patients were accepting of long-term treatment while others desired a relatively brief option. Among patients who had returned to use, potentially important issues emerged pertaining to the absence of patient outreach for missed medication appointments and inadequate discharge planning following stays at rehabilitation facilities. Conclusions: While results regarding the importance of patient motivation and strong patient-prescriber relationships have been noted in previous studies, other findings regarding opportunities to improve patient outreach and coordination of care have received relatively less attention and warrant further consideration.

Scope of, Motivations for, and Outcomes Associated with Buprenorphine Diversion in the United States: A Scoping Review.

BACKGROUND: Expanding access to medications to treat opioid use disorder (OUD), such as buprenorphine, is an evidence-based response to the mounting drug overdose crisis. However, concerns about buprenorphine diversion persist and contribute to limited access. METHODS: To inform decisions about expanding access, a scoping review was conducted on publications describing the scope of, motivations for, and outcomes associated with diverted buprenorphine in the U.S. RESULTS: In the 57 included studies, definitions for diversion were inconsistent. Most studied use of illicitly-obtained buprenorphine. Across studies, the scope of buprenorphine diversion ranged from 0% to 100%, varying by sample type and recall period. Among samples of people receiving buprenorphine for OUD treatment, diversion peaked at 4.8%. Motivations for using diverted buprenorphine were self-treatment, management of drug use, to get high, and when drug of choice was unavailable. Associated outcomes examined trended toward positive or neutral, including improved attitudes toward and retention in MOUD. CONCLUSIONS: Despite inconsistent definitions of diversion, studies reported a low scope of diversion among people receiving MOUD, with inability to access treatment as a motivating factor for using diverted buprenorphine, and increased retention in MOUD as an outcome associated with use of diverted buprenorphine. Future research should explore reasons for diverted buprenorphine use in the context of expanded treatment availability to address persistent barriers to evidence-based treatment for OUD.

Post-acute Withdrawal Syndrome.

Post-acute withdrawal syndrome is an underresearched topic that affects many patients with substance use disorders after the cessation of substance use. Post-acute withdrawal syndrome is exemplified by the occurrence of substance-specific withdrawal signs and symptoms lasting well past the known timeframe for acute withdrawal of a used substance. Post-acute withdrawal syndrome may also include signs and symptoms that are not substance specific that persist, evolve, or appear well past the expected acute withdrawal timeframe. Unfortunately, there is very little scientific literature on post-acute withdrawal syndrome. As a result of this, there are no diagnostic criteria for post-acute withdrawal syndrome, and there is no consensus on the proper name for the condition. We present a case of a 38-year-old man who developed post-acute withdrawal syndrome after treatment with buprenorphine for opioid use disorder and review the limited existing literature on post-acute withdrawal syndrome.

Trajectories of non-prescribed buprenorphine and other opioid use: A multi-trajectory latent class growth analysis.

INTRODUCTION: With the increasing use of non-prescribed buprenorphine (NPB), we need more data to identify the longitudinal patterns of NPB use. The goal of this natural history study is to characterize heterogeneity in trajectories of NPB, other opioid use, and participation in medication for opioid disorder (MOUD) treatment among a community-recruited sample of individuals with current opioid use disorder (OUD). METHODS: The study recruited a community-based sample of 357 individuals with OUD who used NPB in the past 6 months in Ohio, United States, for baseline and follow-up assessments (every 6 months for 2 years) of drug use, treatment participation, and other health and psychosocial characteristics. The study used multiple imputation to handle missing data. We used a multi-trajectory latent class growth analysis (MT-LCGA) to find salient groupings of participants based on the trajectories of NPB, other opioid use, and treatment participation. RESULTS: Over time, NPB use frequency declined from a mean of 14.6 % of days at baseline to 3.6 % of days at 24-month follow-up along with declines in heroin/fentanyl (56.4 % to 23.6 % of days) and non-prescribed pharmaceutical opioid (NPPO) use (11.6 % to 1.5 % of days). Participation in MOUD treatment increased from a mean of 17.0 % of days at baseline to 52.4 % of days at 24 months. MT-LCGA identified a 6-class model. All six classes showed declines in NPB use. Class 1 (28 %) was characterized by high and increasing MOUD treatment utilization. Class 2 (21 %) showed sustained high levels of heroin/fentanyl use and had the lowest levels of NPB use (2.2 % of days) at baseline. Class 3 (3 %) was characterized as the primary NPPO use group. Class 4 (5 %) transitioned from high levels of NPB use to increased MOUD treatment utilization. It had the highest levels of NPB use at baseline (average of 80.7 % of days) that decreased to an average of 12.9 % of days at 24 months. Class 5 (16 %) showed transition from high levels of heroin/fentanyl use to increased MOUD treatment utilization. Class 6 (27 %) showed decreased heroin/fentanyl use over time and low MOUD treatment utilization. Classes showed varying levels of improvement in psychosocial functioning, polydrug use, and overdose risks. CONCLUSION: Overall, our findings suggest that NPB use was generally self-limiting with individuals reducing their use over time as some engage in greater utilization of MOUD treatment. A need exists for continuing improvements in MOUD treatment access and retention.

Higher buprenorphine dose associated with increased treatment retention at low threshold buprenorphine clinic: A retrospective cohort study.

INTRODUCTION: Controversy exists regarding effective sublingual buprenorphine dosing for treatment of opioid use disorder (OUD), leading to dose caps of 16 mg per day. The Project Connections at Re-Entry (PCARE) program is a low-threshold buprenorphine clinic that provides medication for OUD to vulnerable populations in Baltimore City. OBJECTIVES: To compare retention in care based on treatment dose of buprenorphine, and to examine associated population characteristics. METHODS: This analysis includes clinical patients who received buprenorphine treatment at PCARE between January and July 2021. The study categorized patients into two dosing groups (16 mg or >16 mg). We conducted chi-square tests of independence for categorical variables and independent sample t-tests for continuous variables to evaluate any significant differences in demographic and clinical characteristics by dosing category. To examine differences in 30- and 90-day retention, we conducted multivariable logistic regression analyses with the outcome variable defined as successful retention (at 30 and 90 days, respectively) controlling for demographic and clinical characteristics. RESULTS: In the study period, 566 patients received buprenorphine treatment at the PCARE van. Patients were primarily male (70.9 %), Black (89.4 %), had a mean age of 46.3 years (SD = 11.5), and a mean opioid use of 22.1 years (SD = 13.5). The majority had previous criminal justice involvement (73.9 %), Medicaid insurance coverage (75.4 %), and were unemployed (69.6 %). Nearly half of the sample had reported a previous overdose event (48.4 %). The study found no significant demographic differences between patients receiving 16 mg of buprenorphine per day compared to patients receiving >16 mg. Patients receiving >16 mg had significantly higher rates of treatment retention at 30 and 90 days: 95.4 % vs 86.7 % (p = 0.001), and 82.7 % vs. 67.6 % (p < 0.001) than those receiving 16 mg, respectively. In a multivariable logistic regression controlling for demographic and drug use characteristics, odds of 30-day (Adjusted Odds Ratio [AOR] = 3.98, 95 % Confidence Interval [CI] = 1.92, 8.74, p < 0.001) and 90-day retention (AOR = 2.56, 95 % CI = 1.55, 4.22, p < 0.001) were greater among patients receiving >16 mg daily compared to 16 mg. CONCLUSIONS: In this study examining patients with OUD in a low-threshold buprenorphine clinic, we observed higher rates of treatment retention with buprenorphine doses >16 mg.