Outpatient opioid use disorder treatment for the ID physician

Benefits of opioid use disorder treatment

OUD is a chronic, relapsing condition that, when not managed, contributes to poor outcomes for OUD itself, and for the management of other medical and psychiatric conditions [ ]. Long-term pharmacotherapy (also known as medication-assisted therapies) is the cornerstone of effective treatment for OUD and is superior to behavioral treatment alone [ ]. These evidence-based medications act on mu and kappa opioid receptors to block the euphoric effects of other opioids, while reducing cravings and symptoms of opioid withdrawal [ ]. Evidence-based medications include maintenance with methadone (pure opioid agonist), buprenorphine (partial opioid agonist/partial antagonist), and naltrexone (pure opioid antagonist). Opioid receptor agonists, like methadone and buprenorphine, consistently reduce overdose and related mortality [ ], prevent relapse, improve social functioning, and improve mental and physical health. Initiation of pharmacotherapy by itself after nonfatal overdose is associated with a profound decrease in all-cause and opioid-related mortality [ ]. This includes improved mortality from infective endocarditis [ ], as well as improvements along the entire HIV treatment cascade and in Hepatitis C treatment [ ]. Opioid agonist treatment increases HIV treatment engagement, including engagement in HIV care, initiation onto and adherence with ART retention, and viral suppression, as well as decreases ART drop-out relative to matched patients with HIV not on opioid agonist therapy [ ]. Opioid antagonist treatment with extended-release naltrexone has been shown to reduce relapse [ , ] overdose [ ] and improve HIV viral suppression [ ]. OUD treatment is also a primary prevention of HIV [ , ] and HCV by reducing or eliminating the frequency of injection[ ]. Thus, ID specialists can be more effective when they are able to engage their patients in treatment for OUD.

To treat opioid use disorder successfully, recognize that it is a chronic, relapsing and remitting disease of the brain

OUD is a chronic, relapsing condition that can be successfully managed over a lifetime. Despite effective treatments, however, relapse is common and expected, similar to patients with diabetes with poorly controlled glucose after eating a high caloric meal. Relapse rates for OUD are similar to those of other chronic diseases such as diabetes, hypertension, and asthma, which also require both pharmacologic and behavioral treatment modalities [ ]. Practitioners may perceive that relapse during treatment is a failure, but this is not accurate. Successful treatment requires ongoing evaluation and treatment modification. Similar to diabetes and HIV, relapse indicates the need to adjust, restart, or change treatment. Treatment must keep patients engaged, as multiple episodes of treatment may be needed, and adequate treatment length is critical for good outcomes. A central predictor of retention in treatment using opioid agonist treatment is adequate dosage—most patients are prescribed suboptimal dosages [ , ]. Duration of treatment for this chronic condition can vary; 1 year is considered an absolute minimum for maintenance, but typical duration of treatment is several years, and can even be a lifetime [ ] .

Barriers to opioid use disorder treatment

The current opioid crisis in the United States has unveiled shortcomings in our ability to provide treatment. Despite documented efficacy of pharmacotherapy, only 10% of people with OUD in the United States who are eligible for treatment receive it [ ]. Barriers to treatment are multilevel and include those at the patient, clinician, and structural levels. Patients are often not ready to stop using [ ], have inaccurate beliefs about the availability and effectiveness of pharmacotherapies [ ], have preference for counseling and abstinence-based programs despite evidence favoring medication [ ], experience stigma against both OUD itself and its treatment [ ], and are overly optimistic about their risk of avoiding relapse [ ]. Clinician-level barriers to treatment expansion include perceived time constraints, concerns about diversion, unwillingness to prescribe, not perceiving patient need, and low confidence in their ability to prescribe pharmacotherapy. This may rise from inadequate training and stigma against patients with OUD (see Table 9.1 ) [ , ]. Structural barriers limiting treatment access include shortage of trained providers, reimbursement models that do not adequately compensate for care coordination and psychosocial services, stigma, geographical barriers (extensive travel to treatment in rural areas) [ ], long waitlists for treatment entry [ ], restrictions on the number of patients that can be treated, and lack of Medicaid expansion in some states [ ].

Scale-up of opioid use disorder treatment is a critical public health priority: an overview of expansion strategies

OUD can be treated in a number of nonaddiction clinical settings. One of the key challenges in addressing the opioid crisis is ensuring that OUD treatment scale-up in these settings is prioritized and supported. An expansion strategy focusing only on specialty addiction treatment settings will be inadequate to overcome existing barriers to treatment. Instead, increasing treatment access requires a multipronged strategy that includes treatment of OUD in multiple settings, like primary and IDs clinical care, the justice system, emergency departments, during hospitalization, and, eventually, in pharmacies. Expanding access and uptake in treatment is a national public health priority for addressing the opioid crisis [ , ].

Strategies for expanding access can begin with existing opioid treatment centers. Conventionally, specialty treatment centers utilize a high-threshold approach that limits patient access [ ], such as highly selective intake criteria, long waiting lists, no primary care access, high cost of treatment, and exclusion of patients with comorbid conditions. Once in treatment, patients may face punitive discharge policies, lack of treatment individualization, no shared patient decision-making, and other barriers to retention. In contrast, innovative, low-threshold models that have decreased barriers and increase service capacity, as with an open-access system, have been shown to deliver care while preserving patient outcomes without increase in cost [ ].

Access and capacity can be further expanded with nonspecialty sites that conduct intake and monitoring (i.e., clinics, emergency departments, hospitalization, pharmacies, and the justice system). This is exemplified in the Hub and Spoke model [ ]. The hub is the existing opioid treatment specialty center with a board-certified addiction specialist, able to dispense methadone, buprenorphine, and other related treatments. Community and healthcare sites serve as spokes into the hub. Transfers between hubs and spokes are bidirectional. Hubs can do initial intake and evaluate appropriate treatment placement for more stabilized patients. Patients can thus be initiated on buprenorphine within the hub then transferred to primary care provider. Alternatively, patients may be initiated on buprenorphine at clinics, or during the crucial windows of acute crisis (nonfatal overdose, infections in hospitals, or transition from justice system to community). Patients can then be referred to the hub for further evaluation, or reevaluation if they are having inadequate response to treatment. This model is akin to the provision of medical care where a specialty hospital or academic medical center serves as a hub and smaller nearby hospitals and clinics serve as the spokes. This can be further expanded with telemedicine, which uses videoconferencing to conduct remote diagnosis and treatment. Evidence for telemedicine's effectiveness in mental health is well-established, though it is currently nascent in addiction treatment. Despite advocacy from the President's Commission on Combating Drug Addiction and Opioid Crisis [ ] and the American Society of Addiction Medicine, several barriers exist to telemedicine expansion [ ]. Even so, its use has increased and may be a promising means by which to overcome barriers to care in areas with low access to providers, such as in rural areas [ ]. Additionally, telemedicine can be used for distance-based learning by providing tele-education to connect primary care providers with specialty care for facilitating case-based learning, as in Project ECHO (Extension for Community Healthcare Outcomes). This can expand access to specialized treatments in underserved areas, including in primary care, justice, and IDs clinical care settings [ ]. Outside the United States, OUD treatment can additionally be provided in pharmacies and overseen by pharmacists, a strategy that has been used successfully in the United Kingdom [ , ] .

Expansion of opioid use disorder pharmacologic treatment in nonaddiction specialty clinics is a promising public health strategy

Primary care and other specialty ambulatory clinics (e.g., HIV clinical care settings, hepatology practices treating HCV) are a high priority and promising opportunity for treatment expansion [ ] but have been underutilized [ ]. Primary care is deeply essential, as treating OUD without comprehensive medical care is associated with an increased hazard of death [ ]. In addition to being at the frontlines of care (especially for underserved and vulnerable populations), primary and ID physicians are especially expert at managing complex patients with multiple comorbidities requiring coordination of care with specialists [ , ]. The ambulatory clinic is therefore especially well-suited for serving as a medical home for OUD [ ]. International guidelines [ ], including those from the International Association of Physicians in AIDS Care (IAPAC), recommend integration of treatment for OUD as a key priority for optimizing HIV treatment outcomes [ ].

Indeed, HIV providers have long called for integration of services to improve care for their patients [ , ], including for mental health, gynecological, hepatitis C, and other services, in addition to treating addiction. One of the earliest models for integrating OUD into multidisciplinary care was the BHIVES collaborative, which called for introducing buprenorphine into the HIV care setting. This 10-site demonstration project showed not only feasibility but that HIV patients initiated on buprenorphine were significantly more likely to initiate ART and to achieve viral suppression [ ]. Additional models have emerged from the initiative, confirming that buprenorphine treatment could easily be delivered by both HIV and addiction medicine specialists. Such models do require a “glue” person—nurse, counselor, social workers, or other individual who was able to coordinate the activities—for successful implementation [ ]. Several representative models of integrating OUD treatment into HIV clinical care settings have since been identified [ ]. The primary care model posits that the primary clinician be responsible for managing OUD, only referring when patients become too complicated. The onsite addiction specialist places an expert within the clinic (colocation), providing addiction treatment onsite. A hybrid model allows for the addiction expert to induct patients and refer stable patients to all providers. An emerging model showing promise is group visit models, in which providers see many patients at once, which improves symptoms, retention, and provides a unique peer support [ , ]. All models include four central components: pharmacologic therapy, complementary psychosocial services, integration of care, and education and outreach [ ].

Legislative history for expanding access to pharmacotherapy in the ambulatory setting

The Drug Abuse Treatment Act (DATA) of 2000 allowed FDA-approved schedule III-V opioid agonists for OUD treatment to be provided outside of specific federally approved treatment programs. The only opioid agonist meeting these criteria is buprenorphine, which was FDA-approved in 2002. Per DATA 2000, physicians can prescribe buprenorphine in settings other than licensed treatment centers if they complete an 8-hour training and apply to receive a waiver. Any physician is eligible to become a buprenorphine prescriber if they have an active state medical license, is registered with the Drug Enforcement Agency (DEA) to prescribe controlled substances, and is able to provide or refer patients to counseling and support services. The 8-hour training courses are available online, in person, or in combination formats. Popular courses are offered by the American Academy of Addiction Psychiatry, American Society of Addiction Medicine (ASAM), and Substance Abuse and Mental Health Services Administration (SAMHSA). The SAMHSA website also has a short online application for the waiver itself [ ].

In 2016, with the Comprehensive Addiction and Recovery Act (CARA), the patient limit was expanded from 30 patients per practitioner and 100 patients after 1 year to additionally allow qualified waivered physicians to expand to 275 patients. CARA also broadened prescribing privileges to nurse practitioners and physician assistants [ ]. Methadone, in contrast, is schedule II and available in the United States in licensed and accredited specialty treatment programs [ , ]. No waiver is required to administer extended-release naltrexone (XR-NTX), which is not a controlled substance.