Research has shown that opioid-addicted patients have a very high rate of relapse if they are not given long-term opioid maintenance therapy, but how long that therapy should last and when it can be safely discontinued remain unanswered questions.
Clinicians have little more than anecdotes to go on, the speakers agreed at a workshop at APA's 2010 annual meeting in New Orleans in May. Before research is conducted, addiction psychiatrists should be mindful of the proven effectiveness of long-term maintenance therapies with methadone and buprenorphine and the risk of premature treatment discontinuation, they recommended.
The workshop, titled "Maintenance Treatment for Opiate Dependence: Terminable or Interminable?," was part of a track sponsored by the National Institute on Drug Abuse (NIDA).
Detoxification followed by abstinence "carries the risk of a very high relapse rate and treatment failure," Steven Batki, M.D., a professor of psychiatry and behavioral sciences at Upstate Medical University in Syracuse, told attendees. He cited studies and reviews consistently showing that about two-thirds of opioid-dependent patients would relapse without maintenance therapy. For example, in a study published in the March 8, 2000, Journal of the American Medical Association, Karen Sees, D.O., and coauthors found that methadone maintenance therapy was more effective than abstinence-based psychosocial treatment for reducing heroin use and retaining patients in treatment.
The "right" duration of methadone or buprenorphine treatment is clinically driven by the objectives of treatment, such as increasing life expectancy, reducing morbidity, improving health and quality of life, decreasing heroin and other substance use, decreasing crime, and minimizing costs to family and society, Batki noted.
"At present, [opioid receptor] agonist and partial-agonist maintenance treatment of open-ended and uncertain duration appears to be closest to a ‘cure’," Batki said.
Because of its short time on the market, there is less long-term evidence on buprenorphine, according to Herbert Kleber, M.D., a professor of psychiatry and director of the Division on Substance Abuse at the New York State Psychiatric Institute. No clinical trial data are currently available. His recommendation is to taper patients off buprenorphine very slowly and carefully; his experience has shown that many patients have difficulty reducing their dosages below 1 mg or 2 mg.
Clinicians should test patients' urine samples throughout the treatment course, Kleber emphasized, because buprenorphine does not appear on a regular urine toxicology screen. Without the test, the clinician would not be able to detect diversion if it occurs.
Both Kleber and Batki noted that research has been unable to offer much useful guidance on predicting prognosis and identifying risk factors for relapse.
The key to the effectiveness of maintenance therapy is treatment retention, which has been shown to significantly reduce mortality and other negative outcomes; however, "in methadone clinics, patients are often discharged from the clinic against their will," said Robert Schwartz, M.D., the medical director and a senior research scientist at the Friends Research Institute in Baltimore.
The patient's autonomy and the methadone clinic's perspective are sometimes in conflict and become a source of tension, according to Schwartz. The methadone clinic staff may be discouraged by a patient's lack of progress or incomplete abstinence despite some degree of improvement. "They may hope to replace that patient with a ‘good’ patient," he said.
On the question of how long the patient will stay in a methadone maintenance program, Schwartz said that about half of patients entering these programs drop out in the first year.
He and his colleagues conducted a study at six methadone clinics in the Baltimore area and found that nearly 80 percent of patients left the programs for program-related reasons. For example, clinics dropped patients who had treatment interrupted because of brief incarceration, drug use, missed medications, failure to adhere to clinic rules, failure to pay nominal fees, or interpersonal conflicts with staff or counselors. Staff frustration often leads to discharge against a patient's wishes, particularly since physicians are typically not closely involved in the program operation on a daily basis.
Since approximately 60 percent of methadone clinics in the United States are run by for-profit entities, there have been concerns about the quality of treatment provided and a lack of sufficient physician oversight at many clinics, Kleber noted.
To increase patient retention and improve outcomes at methadone clinics, Schwartz suggested several approaches: include the patient's need for autonomy and perspective in the treatment plan rather than have the clinic dictate it; review program rules and make them simple, sensible, and patient friendly; change counselors or transfer patient to another program if conflicts arise; and be more cautious in making the decision to discharge a patient.
Furthermore, clinicians should address psychiatric comorbidities while treating addiction, Schwartz recommended. "We also need to make decisions based on the patient's functioning rather than exclusively on urine test results."
The effectiveness of contingency management, which uses a system of incentives and disincentives designed to make abstinence attractive and drug use unattractive, was supported by research on various substance use disorders, Kenzie Preston, Ph.D., a senior investigator and chief of the Clinical Pharmacology and Therapeutics Research Branch within the Intramural Research Program at NIDA, said at the workshop.
There are a variety of flexible contingency-management strategies that can be used effectively along with other treatments, she explained. For example, if a patient meets all the scheduled specimen collections and produces consecutive negative drug-screen results, he or she is given a voucher with monetary value to exchange for various prizes or merchandises. The value of the vouchers can remain the same or increase over time with more clean results. Other forms of reinforcement are assistance with child care, access to housing, vocational training, and greater flexibility with treatment (for example, take-home doses of methadone).
Targeted behaviors are not limited to abstinence from opioid use, she added, but may also include abstinence from other substance use, adherence to naltrexone treatment, and therapy retention.
"As for the question of whether [contingency management] is terminable or interminable, at this point there is no yes or no answer, and [we need to] look at it long term," she said.