The sharp rise in heroin use and prescription opioid abuse in recent years underscores the need for effective treatment for opioid addiction. Yet previous studies have shown that most methadone maintenance treatment (MMT) programs—the primary treatment for opioid use disorders—haven’t provided doses that meet evidence-based standards, 80 mg/day and above. Evidence-based standards are interventions backed by scientific clinical evidence showing that they improve patient outcomes.
With this in mind, the authors of a new study sought the answers to two questions:
- How well are today’s MMTs meeting evidence-based standards of care for methadone doses?
- What characteristics of today’s programs are associated with how well they meet dosing standards?
The article was published online June 10, 2014 in the Journal of Substance Abuse Treatment.
Six waves of a survey conducted in previous years provided data on 718 MMT patients. The University of Michigan’s Institute for Social Research gathered information by telephone contact with directors and supervisors of clinical services during the following years: 1988 (n=172 patients), 1990 (n=140), 1995 (n=116), 2000 (n=150), and 2005 (n=146). Cornell University’s Survey Research Institute obtained additional data, for 140 patients, in 2011. Investigators calculated the percentage of stabilized patients in each program who received doses less than 40, 60, or 80 mg/day, and the percentage receiving doses of 80 mg/day or higher.
In 1988, almost 80 percent of patients received methadone doses too low to be effective, below 60 mg/day. By 2011 that proportion had dropped to 23 percent—a statistically significant improvement, but not good enough.
Looking at the evidence-based standard reveals a more telling story: only 59 percent of patients were receiving at least 80 mg/day. Given that 1,223 methadone programs treated 306,440 patients in 2011, this left more than 125,500 patients denied doses considered necessary to reduce opioid use and increase retention in treatment.
Several factors appear to be involved in underdosing.
For one, the authors see “a potential confusion” in methadone treatment, stemming from two needs: the need to ensure therapeutic dose levels, and the need to individualize dose levels (because of differences in how patients metabolize methadone). As the authors point out, however, “no studies have found that the relationships among methadone dose levels, retention in treatment, and treatment outcomes are mitigated by the need to individualize dose levels.” The fact that optimal doses may vary among individuals shouldn’t prevent programs from giving average doses of 80-100 mg/day. In fact, studies show that patients whose daily doses exceed 80 mg/day “engage in relatively little illicit drug use and have better treatment outcomes,” as long as they maintain average plasma concentrations of about 400 ng/mL.
(As for other factors involved in underdosing, AT Forum notes that for many years some clinicians have disregarded earlier research-based recommendations that MMT patients receive daily doses over 60 mg, claiming favorable clinical experience with lower doses. Some believe that abstinence is an achievable goal, with lower doses making future withdrawal easier. Others have linked lower doses with fewer adverse effects. Still others have cited concerns that larger methadone doses would result in more diversion to the street.)
From prior research, the study’s authors identified factors that reside in the programs themselves, influencing dosing practices (decreases or increases). These include patient characteristics, program characteristics, and “managerial attitudes and beliefs that may run counter to the use of evidence-based practices.” The table below lists them.
|Program Characteristic||Likely Dosing|
|Higher percentages of unemployed patients||Above 80 mg/day|
|Higher percentage of African American and Hispanic patients, compared to non-Hispanic whites||Below 40, 60, or 80 mg/day|
|Patients aged 40 and above||Above 60 or 80 mg/day|
|JCAHO accreditation (not mandated until 2001)||Higher doses|
|Midwest and South location, compared to Northeast||Below 40 mg/day|
|Personnel hold beliefs and values counter to best practices (favor abstinence approaches, oppose syringe exchange, offer limited or no support for HIV prevention measures, etc.)||Below 80 mg/day|
Programs that provide low doses may have another factor in common, the authors note: they may lack important human and financial resources. These resources could include stable work forces that are well trained, well paid, and well educated, and appropriate management systems, such as quality of care indicators and information systems. The authors suggest that examining factors that could be related to low dosing, such as educational backgrounds of personnel, should be a priority for future studies.
Finally, the authors applaud reports, studies, panels, and organizations that may have played a role in significantly improving methadone dose levels. But they return to the fact that too many patients receive doses too low to be effective, and they stress that “policy-makers and managers should emphasize the need for programs with low dose levels to carefully evaluate patient outcomes and take appropriate action.”
This well-designed study was supported by a grant from the National Institute on Drug Abuse.
D’Aunno T, Pollack HA, Frimpong JA, Wuchiett D. Evidence-based treatment for opioid disorders: A 23-year national study of methadone dose levels [Epub ahead of print June 10, 2014]. J Subs. Abuse Treat. doi: org/10.1016/j.jsat.2014.06.001.