28 Long-term Studies on Outcomes for Opioid Use Disorder Patients

Many regions of the U.S. & other countries are in the midst of an opioid epidemic with sharply increasing rates of use, need for treatment, & related mortality.

WHAT PROBLEM DOES THIS STUDY ADDRESS?

While clinical studies have been conducted with regard to short term outcomes across several months, few studies have been completed looking at the course of opioid use disorders across years and decades. Given that we know that opioid addiction tends to have a chronic course lasting many years, studies that highlight long-term treatment outcomes and rates of recovery are needed to inform how providers, systems, and policy makers might address this major public health problem more effectively to enhance remission and recovery rates.

HOW WAS THIS STUDY CONDUCTED?

In the current study, Hser and colleagues reviewed 28 longitudinal studies that followed cohorts of individuals with opioid use disorders for at least 3 years, the substantial majority of whom were recruited from treatment programs.

They reviewed outcomes across several domains including:

mortality
abstinence
further treatment
other health outcomes
incarceration and other criminal justice-related events

WHAT DID THIS STUDY FIND?

Risk of mortality is at least 6 times greater among individuals with opioid use disorder than the general population. However, studies that began to recruit individuals in the year 2000 or later (i.e., after treatment for HIV and AIDS improved dramatically) showed substantially lower mortality rates than earlier cohort studies.
Regarding abstinence, among studies that followed individuals for 10 or more years, only about 30% were abstinent from opioids at the most recent follow-up. Use of other drugs including alcohol was common among these individuals with opioid use disorder, even if demonstrating ongoing opioid abstinence. Regarding formal treatment, multiple treatment episodes are often needed before long-term abstinence is initiated. However, these episodes appear important, with more cumulative time in treatment predicting greater subsequent periods of abstinence.
Regarding other health outcomes, opioid users—including those that initiate abstinence—generally have poorer physical health than the general population. Also, while many studies show that the presence of mental health symptomatology is likely, many experience mental health improvements over time. However, co-occurring depressive disorders may pose added risk to poorer functioning over time.
With respect to crime, authors note that rates of incarceration are conditional on study location; the United States has traditionally approached opioid use from a criminal justice perspective while European countries implemented more of a public health approach. Although incarceration and criminal justice supervision itself may not lead to improved abstinence and recovery, they can be conduits to the treatment system. Indeed, abstinence initiated after a treatment episode is likely to be sustained for more time than when following incarceration. Not surprisingly, longer periods of abstinence are associated with greater reductions in crime.

The current review emphasized the chronic nature of opioid use disorders. In addition, results from several of the reviewed studies suggest a public health—rather than criminal justice-based—approach to opioid use may ultimately enhance outcomes.

Ongoing recovery management strategies including professional (e.g., continuing care relapse prevention groups and medication-assisted treatment) and non-professional (e.g., 12-step mutual-help participation) approaches may be needed to enhances overall rates of remission and recovery. Because opioid addiction can have a lasting negative impact on one’s physical and emotional well-being, a comprehensive biopsychosocial approach may be needed to support services aimed at helping maintain abstinence.

WHY IS THIS STUDY IMPORTANT?

A substantial majority of studies have necessarily focused on developing, evaluating, and disseminating approaches to help individuals stabilize opioid use disorders in the short-term (e.g., up to 1 year after the index help-seeking episode, via medication-assisted and/or psychosocial treatment). The current study is important in that it provides a macro, longitudinal context to inform treatment and policy decisions.

LIMITATIONS

The opioid misuse and related treatment/recovery landscape has changed considerably during the past 5 to 10 years. This may limit the applicability and generalizability of their findings to those currently in or seeking treatment.
Many of the study samples reviewed included heroin users only. Misuse of pharmaceutical opioids, such as oxycodone and its various formulations (e.g., Percocet), however, has increased dramatically in more recent years. In 2013, for example, there were approximately 8,000 overdose deaths related primarily to heroin and 16,000 related to pharmaceutical opioids in the U.S.
Many of the studies included patients from specialized methadone maintenance programs while newer medication-assisted treatments such as buprenorphine/naloxone (Suboxone) have become more popular and accessible (i.e., through primary care clinics). A recent study by Weiss et al., for example, found that, 42 months after initially receiving Suboxone (i.e., agonist medication) as part of a randomized controlled trial targeting prescription opioid use disorder, about one-third of were abstinent from illicit opioids and not on agonist medication, and another one-third was abstinent from opioid use disorder while still on agonist medication. This means that about two-thirds of patients treated for prescription opioid addiction were in remission roughly four years following treatment.
Existing medications have been enhanced through medical technology. For example, naltrexone, formerly only available as a daily pill, is also now available as a monthly injectable formulation (Vivitrol). Many questions regarding long-term recovery from opioid addiction remain unanswered in the face of this changing landscape.

NEXT STEPS

Ongoing follow-up studies of individuals seeking treatment in this newer age of opioid addiction and treatment are needed, such as the Weiss et al. study mentioned above.

BOTTOM LINE

For individuals & families seeking recovery: Opioid use disorder can take several treatments and relapses before sustained abstinence is achieved. This is a statistical average, so one may achieve abstinence quickly, especially if they remain committed to engaging with ongoing recovery support services. The risk of relapse drops substantially after 5 years of continuous remission, but there is always at least some degree of relapse risk.
For scientists: At present, there is a sufficient body of literature to support development, evaluation, and dissemination of methods to engage individuals with opioid use disorders with continuing care after an initial index episode. Longitudinal cohort studies of addicted individuals who have sought treatment more recently are needed to inform clinical and recovery support service provision given the changing landscape of opioids in the U.S. and globally.
For policy makers: Strongly consider funding initiatives consistent with a chronic illness model for opioid addiction such as strategies to engage addicted individuals with continuing care and recovery support services following initial stabilization.
For treatment professionals and treatment systems: Strongly consider including continuing care approaches in your treatment program, or partner with providers and/or systems that can help provide ongoing recovery management. Ongoing engagement with formal and informal recovery specific supports is recommended for a minimum of five years.

CITATIONS

Hser, Y. I., Evans, E., Grella, C., Ling, W., & Anglin, D. (2015). Long-term course of opioid addiction. Harv Rev Psychiatry, 23(2), 76-89. doi: 10.1097/hrp.0000000000000052

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