Preliminary Observations In Substitution Treatment of Opioid Dependence

The International Center 
for Advancement of Addiction Treatment

Considerable evidence indicates a gratifying reduction in the use of heroin in France, and major associated benefits to the general community. This improvement clearly seems related to the massive expansion of opiate-agonist based treatment; the fact that such expansion was possible (development within 4-5 years of the ability to accommodate some 80,000 users!) is itself an encouraging message to other countries (including the United States) seeking to control opiate addiction and its medical and social consequences. The overwhelming reliance on prescribing by generalist, community-based physicians (rather than specialized « programs ») seems to have been a sine qua non of the favorable French experience in recent years. And finally, disparate rules and regulations governing the use of the specific medications to treat heroin addiction preclude reliance on evidence-based medicine to guide the medical profession in its treatment of this illness.



Heroin Use Indicators

Since 1994 there has been a dramatic improvement in the health of heroin users in France. The most striking, quantifiable, success is evidenced by the drop in fatal overdose cases, from 566 in 1994 to 118 in 1999 — a decline of 80% during this five- year period! While the absolute numbers of overdose deaths are probably understated, since they are based on police records of individuals dying on the streets (as opposed to deaths in hospitals, for example), the relationship of the data from the two time periods, during which the method of counting did not change, supports strongly the conclusion that there has been a major drop in mortality due to overdose.

Along with the marked decline in fatal overdoses, there has been a substantial decrease in HIV-related mortality among intravenous drug users — from 1,040 cases in 1994 to 163 in 1999; this is considerably greater than the decrease in mortality in other major risk groups. Moreover, whereas drug injectors accounted for 26% of new HIV cases in 1992, the proportion had dropped to 14% in 1999. With respect to arrests of heroin users, they continued to rise through 1994, but in the ensuing 4 years – from1995 through 1999 — they dropped by 56%, from 17,149 to 7,469.

The Role Of « Substitution Treatment »

Inevitably, a variety of factors played a role in the dramatic improvement suggested by the data reported above. For example, there was introduction of needle/syringe exchange in 1994 (today there are 115 such programs), as well as outreach efforts to facilitate referral to hospitals, physicians and other service providers. It seems highly likely, however, that the major cause was the massive expansion of « substitution » treatment of heroin addiction by Buprenorphine and methadone. Prior to 1994 there was very little experience with such treatment in France; a few physicians prescribed Buprenorphine even though it was illegal, and methadone patients in the entire country numbered only a few dozen. In 1996, however. Buprenorphine prescribing was legalized, with no restrictions or limitations other than those applicable to any narcotic, prescribed for any purpose. Methadone, on the other hand, while permitted to expand considerably, was constrained by a variety of regulations unique to this medication. Thus, patients had to be « stabilized » on methadone in a specialized treatment center before being permitted to receive their on-going care by generalist practitioners. Also, while pharmacies could dispense 28 days of Buprenorphine, methadone patients were limited to a maximum of seven days at a time. Small wonder that Buprenorphine has become the overwhelming choice of physicians and patients alike.

No special training is required of physicians to permit their prescribing either of the two medications. Many practitioners join « town-hospital networks, » to provide mutual support and guidance. Others choose to practice independently. Overall, it is estimated that about 10% of generalist physicians prescribe substitution treatment.

By 1999, opiate agonist treatment was being provided to an estimated 80,000 people. Of these, some 70,000 received Buprenorphine, almost all in a private practice, generalist medical care setting. Approximately 10,500 were being prescribed methadone, roughly half by generalist doctors and half by special addiction treatment centers. (Note: these figures are not based on patient census data, but rather on the annual sales of both medications in France, and an estimated average daily dose of 8mg Buprenorphine and 60mg methadone).

The striking reliance on Buprenorphine as opposed to methadone does not reflect evidence-based medicine or pharmacological properties of the two medications, but rather the disparate governmental restrictions referred to above. Certainly, the potential for misuse of Buprenorphine is very real. Thus, surveys conducted among patients indicate that as many as 49% of patients inject the medication initially, although this figure drops to about 20% with increasing duration of treatment. In Marseille a survey of risk-taking among 110 opiate injectors found 70% to be using Buprenorphine – a rate identical to that found among needle exchange program clients. In fact, many of the patients who today receive methadone treatment cite as the reason for their preference to desire to stop injecting.

With regard to treatment duration, no limitations exist, and the experience is very good – approximately 85% remaining on methadone after one year, and 75% on Buprenorphine. A persistent problem among a significant proportion of patients receiving either of the two medications is the use of illicit cocaine — conservatively estimated at 8%, but generally considered to be much higher.

Posté dans English.