A Canadian study shows that heroin maintenance keeps some patients in drug
treatment longer than methadone therapy and reduces illegal behaviors in
certain difficult-to-treat patients with chronic relapsing opioid addiction.
Meanwhile, clinicians and other addiction experts continue to debate the
efficacy of various addiction treatment approaches.
The new study, known as the North American Opiate Medication Initiative
(NAOMI), was conducted by Eugenia Oviedo-Joekes, Ph.D., and colleagues at the
University of British Columbia and the Université de Montréal
and published in the August 20 New England Journal of Medicine. It
was funded by the Canadian Institutes of Health Research, Canada Foundation
for Innovation, Canada Research Chairs Program, the universities of British
Columbia and Montreal, and provincial government agencies.
From 2005 to 2008 in Montreal and Vancouver, patients who had
DSM-IV-diagnosed opioid dependence, injected heroin daily, and had
failed at least two previous treatments including at least one methadone
treatment were recruited for the study. Participants were randomized to
receive either oral methadone (n=111) or diacetylmorphine injection (n=115)
treatment for 12 months in an open-label design. Diacetylmorphine is the
active ingredient in heroin and was self-administered by participants under
medical supervision at the study clinics.
Nearly 88 percent of heroin-treated patients remained in the treatment at
the end of one year, statistically significantly higher than the 54 percent
retention rate for the methadone-treated patients.
In addition, 67 percent of heroin-treated patients met the criteria for
responders in terms of reduced illicit-drug use or illegal activities,
compared with 48 percent of methadone-treated patients, also a statistically
significant difference. Patients were considered responders if they had at
least a 20 percent reduction from baseline in either the illicit-drug use or
the illegal-activity subscales of the European Addiction Severity Index.
The study protocol allowed participants to self-administer diacetylmorphine
at a maximum of three times a day, with a dose of no more than 1,000 mg/day.
The actual dose used by participants averaged 392 mg/day. The mean dose of
methadone given in the study was 96 mg/day.
Diacetylmorphine use was associated with more serious adverse events,
including overdose in 10 patients, which required immediate treatment with
naloxone, and seizure in six patients.
The findings from this study were not unexpected and were similar to those
from several studies conducted in Germany, Switzerland, the Netherlands, and
Spain since the 1990s on heroin-maintenance treatment in chronically addicted
patients. The most recent was a German study by Christian Haasen, M.D., and
colleagues at the University Medical Center Eppendorf in Hamburg and published
in the July 2007 British Journal of Psychiatry.
In these studies patients who received heroin-maintenance treatment in a
supervised environment were found to do better than patients who received
methadone on a number of outcome indicators such as improvement in physical
health and decreased criminal behaviors. The Canadian study, however, is the
first heroin study published in a major U.S. medical journal.
These studies do not demonstrate that heroin-maintenance treatment is more
efficacious than methadone, Charles O'Brien, M.D., Ph.D., told Psychiatric
News. Rather, the findings are limited to a small segment of
opioid-addicted patients. "The [heroin-maintenance] approach represents
a second-class therapy for people who refuse to get methadone
treatment," he said.
O'Brien is the Kenneth Appel Professor of Psychiatry at the University of
Pennsylvania and chair of the DSM-V work group on areas related to
addiction psychiatry. He also served as a consultant for the
heroin-maintenance study in the Netherlands.
Commenting on the NAOMI study, O'Brien noted that the research protocol
gave participants the option of a maximum of three injections of heroin a day.
Maintaining opioid addicts on heroin as the Canadian researchers did "is
a way of harm reduction, but [patients] were not motivated to change their
lives," he said. "They get high three times a day, which
interferes with normal life.... Methadone or buprenorphine treatment can
Heroin maintenance is also prohibitively expensive, O'Brien emphasized. It
would be unwise to adopt it widely in the U.S. health care context, where
treatments for addiction, such as methadone and buprenorphine, are poorly
funded in the first place. "We don't even have enough money for
methadone therapy. We should put the funds into making methadone and
buprenorphine treatment and proper counseling available to more people with
opioid dependence, which will make a far bigger difference."
Trends in opioid addiction treatment "often owe more to the politics
of the situation" and to "professional factors" than to
research evidence, Virginia Berridge, Ph.D., a professor in history and public
health policy analysis at the London School of Hygiene and Tropical Medicine,
University of London, wrote in an accompanying editorial. She pointed out that
in countries where the opioid-addiction studies were conducted, Switzerland
and the Netherlands have chosen to adopt heroin maintenance as a treatment
option, but Germany and Spain have not.
An abstract of "Diacetylmorphine Versus Methadone for the
Treatment of Opioid Addiction" is posted at<content.nejm.org/cgi/content/abstract/361/8/777>.
An abstract of "Heroin-Assisted Treatment for Opioid Dependence:
Randomised Controlled Trial" is posted at<bjp.rcpsych.org/cgi/content/abstract/191/1/55>.▪